Jurnal Crystal : Publikasi Penelitian Kimia dan Terapannya
type: channel
description: Jurnal ini memuat dan menerbitkan artikel sesuai dengan bidang ilmu kimia murni dan terapan yaitu kimia analitik, kimia organik, kimia anorganik, biokimia, kimia material, teknik kimia, kimia kosmetik, kimia bahan pangan, kimia lingkungan dan kimia edukasi. Terbit dua kali dalam setahun yaitu bulan maret dan september oleh Program Studi Kimia, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas PGRI Banyuwangi. Informasi terbaru Jurnal Crystal 2024
publisher: Program Studi Kimia, Fakultas MIPA, Universitas PGRI Banyuwangi
language: en-US
publication name: Jurnal Crystal : Publikasi Penelitian Kimia dan Terapannya
issn: 2685-7065
copyright: Creative Commons Attribution-4.0 International License
items: MASS BALANCE ANALYSIS OF GLUCOSE FROM SUGARCANE BAGASSE THROUGH ULTRASONIC ENZYMATIC HYDROLYSIS
items: ANALISIS KUALITAS AIR MINUM DAN KANDUNGAN LOGAM BERAT TIMBAL (Pb) PADA DEPOT AIR MINUM ISI ULANG (DAMIU) DI KOTA PALANGKA RAYA-KALIMATAN TENGAH
items: ANALYSIS OF MnO2 RECOVERY STUDY FROM DRYCELL BATTERY WASTE: A REVIEW
items: ISOLATION AND STRUCTURAL ELUCIDATION OF FLAVONOID FROM BOESENBERGIA PANDURATA RHIZOME
items: KAJIAN SIFAT FISIKA DAN KIMIA BIOPLASTIK DARI PATI BIJI NANGKA (Artocarpus heterophyllus)
items: OPTIMASI FORMULA KRIM EKSTRAK DAUN AFRIKA (Vernonia Amygdalina Del.) SEBAGAI ANTIJAMUR CANDIDA ALBICANS ATCC 10231
items: EKSPLORASI ZAT WARNA ALAMI DARI KULIT KAYU TINGI (Ceriops Tagal) DENGAN VARIASI TEKNIK PEMORDANAN
items: POTENSI TEMPURUNG KELAPA DAN KULIT JENGKOL SEBAGAI BAHAN ALTERNATIF BRIKET BIOPELLET DENGAN PEREKAT TEPUNG TAPIOKA UNTUK ENERGI TERBARUKAN
items: DETERMINATION OF LEAD (PB) CONTAMINATION IN LETTUCE (Lactuca sativa L.) FROM VARIOUS COLLECTION SOURCES IN BANDA ACEH, INDONESIA
items: PENGARUH KONSENTRASI AKTIVATOR KOH PADA KUALITAS KARBON AKTIF DARI KULIT SINGKONG
items: PENGARUH DOPING CUO DAN ZAT ADITIF MONOETHANOLAMINE (MEA) PADA SINTESIS TIO2 MENGGUNAKAN METODE SOL-GEL TERHADAP BAND GAP ENERGY
items: EKSTRAKSI DAN KARAKTERISASI PEKTIN DARI LIMBAH KULIT JERUK (CITRUS SINENSIS (L.)) SEBAGAI MATERIAL POTENSIAL ADSORBEN
items: GC–MS CHARACTERIZATION OF FATTY ACID ALKYL ESTERS IN BIODIESEL PRODUCED FROM WASTE COOKING OIL
items: SUSTAINABLE LIGNIN EXTRACTED FROM BANANA STEM BIOMASS AS A FUNCTIONAL UV-BLOCKING INGREDIENT IN SUNSCREEN
items: KARAKTERISASI KIMIA DAN MORFOLOGI BIOKOKAS DARI BAGLOG JAMUR DENGAN PEREKAT LIMBAH LILIN MALAM BATIK MENGGUNAKAN FTIR DAN SEM
items: EMULGEL EKSTRAK ETANOL DAUN SUMAMBU (HYPTIS CAPITATA JACQ.) SEBAGAI KANDIDAT ANTIBAKTERI TERHADAP STAPHYLOCOCCUS AUREUS ATCC 25923
items: CEMARAN MIKROBA DAN KADAR AIR PADA PENYEDAP RASA ALAMI BERBAHAN DASAR TEMPE DAN UDANG EBI
items: XYLOKETAL DERIVATIVES FROM XYLARIA SP. AS STRUCTURAL LEADS FOR DUAL MYC/BCL2 AXIS MODULATION FOR DOUBLE-HIT HIGH-GRADE B-CELL LYMPHOMA: A DOCKING-BASED INVESTIGATION
items: ANALISIS BIBLIOMETRIK PENELITIAN HIDROGEL KONDUKTIF SODIUM ALGINAT DENGAN VOSVIEWER
items: UJI AKTIVITAS BROMELIN DARI ANANAS COMOSUS DAN PAPAIN DARI CARICA PAPAYA TERHADAP PH MENGGUNAKAN METODE SPEKTROFOTOMETRI UV-VIS
items: PENGARUH VARIASI POTENSIAL ANODISASI TERHADAP SIFAT OPTIK TIO2 NANOTUBE ARRAYS (TNAS) MENGGUNAKAN METODE ANODISASI DUA TAHAP
items: A LOW-COST COLORIMETRIC DETECTION OF HG2+ USING PAPER-BASED SENSOR WITH EUCLIDEAN DISTANCE APPROACH
items: ANALISIS KANDUNGAN TIMBAL PADA MINUMAN SUSU CAIR KEMASAN KALENG DI TONDANO MENGGUNAKAN SPEKTROFOTOMETRI SERAPAN ATOM
items: PENENTUAN INHIBITOR SELEKTIF DALAM MENGHAMBAT KERJA ENZIM SIKLOOKSIGENASE-2 dan EFEK MUTASI RESIDU ASAM AMINO SECARA IN SILICO
items: ANALISIS KUALITAS AIR TANAH SUMUR BOR BERDASARKAN PARAMETER FISIKA, KIMIA DAN MIKROBIOLOGI DI LINGKUNGAN KAMPUS UNIVERSITAS BANGKA BELITUNG
items: SURFACE AREA DRIVEN CRYSTALLINITY CHANGES OF HYDROXYAPATITE DURING SIMULATED BODY FLUID IMMERSION
items: PERBANDINGAN AKTIVITAS ANTIOKSIDAN EKSTRAK ETANOL DAUN COCOK BEBEK (Kalanchoe pinnata) DENGAN METODE DPPH DAN ABTS
items: PENGARUH PENGGUNAAN KALIUM HIDROKSIDA DAN ASAM FOSFAT TERHADAP AKTIVITAS AMPAS KOPI DALAM PENGOLAHAN MINYAK JELANTAH
items: PENGARUH VARIASI KOMPOSISI TERHADAP KARAKTERISTIK BIOBRIKET BERBAHAN BAKU BIOMASSA MELALUI METODE KARBONISASI

MASS BALANCE ANALYSIS OF GLUCOSE FROM SUGARCANE BAGASSE THROUGH ULTRASONIC ENZYMATIC HYDROLYSIS
type: item
description: This study explores the conversion of sugarcane bagasse into glucose through an enzymatic ultrasonic hydrolysis process. Initially, the bagasse undergoes delignification using 6% sodium hydroxide to remove lignin and free cellulose for further processing. The delignified bagasse is then hydrolyzed using cellulase enzyme under ultrasonic conditions. The results indicate that glucose production is influenced by factors such as raw material preparation, enzyme activity, temperature, and pH. Mass balance calculations were applied to assess the input and output of materials throughout the delignification and hydrolysis processes. The findings show that 10 grams of delignified sugarcane bagasse yielded 5.955 grams of glucose, demonstrating the potential of sugarcane bagasse as a source of bioenergy through glucose production. These results support the utilization of agricultural waste in bioethanol production and contribute to sustainable energy development.
creator: Erwan Adi Saputro
creator: Adithya Daffa Rabbani
creator: Miranda Annisa Anwar
creator: Wiliandi Saputro
creator: Intan Suhada Azmi
creator: Ardika Nurmawati
rights: Copyright (c) 2026 Erwan Adi Saputro, Adithya Daffa Rabbani, Miranda Annisa Anwar, Wiliandi Saputro, Intan Suhada Azmi, Ardika Nurmawati https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 1
ending page: 6
doi: 10.36526/jc.v8i1.6135

ANALISIS KUALITAS AIR MINUM DAN KANDUNGAN LOGAM BERAT TIMBAL (Pb) PADA DEPOT AIR MINUM ISI ULANG (DAMIU) DI KOTA PALANGKA RAYA-KALIMATAN TENGAH
type: item
description: An analysis of drinking water quality, including physical parameters such as TDS (Total Dissolved Solids), color, odor, and taste, as well as chemical parameters such as pH and lead ion content in refillable drinking water depots in Palangka Raya City, has been conducted. Drinking water requirements must comply with the Regulation of the Minister of Health of the Republic of Indonesia Number 2 of 2023 concerning the Implementation of Government Regulation Number 66 of 2014 regarding Environmental Health. The method throughout this investigation is laboratory experiment. Samples of refillable drinking water were obtained using a random sampling method at 9 different locations in Jekan Raya District. Based on the analysis of physical parameters including TDS, color, odor, and taste, the drinking water sample still meets drinking water quality standards. The results of pH measurements at 7 out of 9 sampling points showed that the pH values of 6.5-8.5 did not meet the quality standards. Analysis of lead (Pb) levels based on AAS showed that the Pb content in 9 samples was below the maximum permissible standard of 0.01 mg/L.
creator: Dwi Hermayantiningsih
creator: Muh. Supwatul Hakim
creator: Tety Wahyuningsih Manurung
rights: Copyright (c) 2026 Dwi Hermayantiningsih, Muh. Supwatul Hakim, Tety Wahyuningsih Manurung https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 7
ending page: 14
doi: 10.36526/jc.v8i1.5945

ANALYSIS OF MnO2 RECOVERY STUDY FROM DRYCELL BATTERY WASTE: A REVIEW
type: item
description: Global demand for manganese dioxide (MnO₂) materials is increasing rapidly as the battery and catalyst industry develops, while the availability of primary ores continues to decline. Waste dry cell batteries contain high amounts of MnO₂, making them potentially a secondary source of economically valuable manganese metals. This study systematically discusses various microwave-assisted hydrometallurgy-based hydrometallurgy approaches for the recovery of MnO₂ from waste batteries. The literature study was conducted by examining 50 current scientific references covering three main aspects: extraction methods, the influence of heating methods, and purification strategies. The core conclusion of this review is that microwave-assisted leaching represents the most efficient extraction approach, delivering recovery rates up to 95.1% that significantly surpassing conventional methods (82–85%) while reducing reaction times and energy consumption by up to 40%. Furthermore, this study concludes that chemical oxidation using KMnO4​ is the superior purification strategy, capable of producing MnO2​ with purity exceeding 98%. Consequently, this review establishes that the integrated system of microwave-assisted leaching and selective KMnO4​ oxidation offers the most robust, economical, and environmentally friendly blueprint for implementing a circular economy in the metals industry
creator: Erwan Adi Saputro
creator: Muhandis Akbar Winaji
creator: Muchammad Fahrizal Hanif
creator: Ardika Nurmawati
creator: Ely Kurniati
creator: Caecilia Pujiastuti
rights: Copyright (c) 2026 Erwan Adi Saputro, Muhandis Akbar Winaji, Muchammad Fahrizal Hanif, Ardika Nurmawati, Ely Kurniati, Caecilia Pujiastuti https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 15
ending page: 25
doi: 10.36526/jc.v8i1.6498

ISOLATION AND STRUCTURAL ELUCIDATION OF FLAVONOID FROM BOESENBERGIA PANDURATA RHIZOME
type: item
description: Temu Kunci (Boesenbergia pandurata) rhizome constitutes a botanical resource long harnessed for ethnomedicinal applications among localized populations. To validate its long-standing traditional application, this investigation aimed to characterize the bioactive chemical profile of the Boesenbergia pandurata rhizome. The dried, pulverized rhizome was initially subjected to maceration for crude extraction of secondary metabolites, followed by a meticulous purification sequence. Vacuum Liquid Chromatography (VLC) was first employed for bulk separation, and subsequent Radial Chromatography refined the flavonoid-rich fractions to yield a pure isolate. The structure of this isolate was then conclusively resolved using advanced 1H-NMR and 13C-NMR spectroscopy, which unambiguously identified the primary compound as pinostrobin.
creator: Moch Abdussalam
creator: Juniarti
creator: Indah Permata Yuda
rights: Copyright (c) 2026 Moch Abdussalam, Juniarti, Indah Permata Yuda https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 26
ending page: 32
doi: 10.36526/jc.v8i1.6518

KAJIAN SIFAT FISIKA DAN KIMIA BIOPLASTIK DARI PATI BIJI NANGKA (Artocarpus heterophyllus)
type: item
description: This study explores the physical and degradability characteristics of bioplastics formulated from jackfruit seed waste starch (Artocarpus heterophyllus), combined with polyvinyl alcohol (PVA) as a plasticizer. The jackfruit seeds were processed into a paste, and the starch was extracted and dried in an oven at 50°C to obtain dry starch. This starch was then tested using an iodine solution, resulting in a purple coloration indicating the presence of starch. Bioplastics were synthesized using different proportions of starch and PVA (0:4, 1:3, 2:2, 3:1, 4:0). The mechanical and biodegradable properties evaluated included tensile strength, elongation, Young’s modulus, water absorption, and degradation rate. The tensile strength ranged between 19.16 MPa and 23.68 MPa, elongation varied from 7.10% to 139.00%, and Young’s modulus values ranged from 0.13 MPa to 3.33 MPa. Optimal mechanical performance was found in the 0:4 and 2:2 formulations. The bioplastic exhibited 116% water absorption and achieved full (100%) degradation within a 7-day period.
creator: Nurakirawati
creator: Radiatul Jannah
creator: Ni Ketut Sumarni
creator: Jusman
rights: Copyright (c) 2026 Nurakirawati, Radiatul Jannah, Ni Ketut Sumarni, Jusman https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 33
ending page: 42
doi: 10.36526/jc.v8i1.6171

OPTIMASI FORMULA KRIM EKSTRAK DAUN AFRIKA (Vernonia Amygdalina Del.) SEBAGAI ANTIJAMUR CANDIDA ALBICANS ATCC 10231
type: item
description: The utilization of natural materials as active pharmaceutical ingredients continues to develop, one of which is the use of Vernonia amygdalina Del. (African leaf) extract as an antimicrobial agent against Candida albicans, a fungus causing skin infections. This study aimed to determine the highest antimicrobial activity between the extract and its active fractions and to optimize a cream formulation using variations of stearic acid, triethanolamine (TEA), and adeps lanae through a factorial design method. Evaluation parameters included pH, viscosity, spreadability, Franz diffusion, and Minimum Bactericidal Concentration (MBC) values. The research was conducted experimentally using the disk diffusion method to determine the highest antimicrobial activity from extracts and fractions obtained using solvents of varying polarity. The extract or fraction with the highest activity was formulated into a cream, which was then tested for physical properties, penetration, and antimicrobial activity using the macrodilution method. The results showed that the African leaf extract exhibited the strongest antimicrobial activity, with an inhibition zone of 17.9 ± 2.33 mm against Candida albicans ATCC 10231. Variations in composition significantly affected pH, viscosity, spreadability, and Franz diffusion parameters. Based on the superimposed contour plot analysis, the optimal cream formulation consisted of 10 g stearic acid, 4 g TEA, and 4 g adeps lanae, achieving a cumulative Franz diffusion penetration of 12.53% and an MBC value of 25%.
creator: Iklila Zahra
rights: Copyright (c) 2026 Iklila Zahra https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 43
ending page: 53
doi: 10.36526/jc.v8i1.6373

EKSPLORASI ZAT WARNA ALAMI DARI KULIT KAYU TINGI (Ceriops Tagal) DENGAN VARIASI TEKNIK PEMORDANAN
type: item
description: Natural dyes derived from plant materials have attracted increasing attention as environmentally friendly alternatives to synthetic dyes in the textile industry. One potential natural dye source is the bark of the tingi tree (Ceriops tagal), which is known to contain tannin compounds capable of producing brownish color on textiles. This study aimed to determine the optimal mordanting technique in the dyeing process of cotton fabric using tingi bark extract. The research employed an experimental laboratory approach by applying three mordanting techniques, namely pre-mordanting, meta-mordanting, and post-mordanting, using alum as a mordant. The extract was obtained through a decoction method and applied to cotton fabric through repeated immersion. Color quality was evaluated through visual assessment by 15 panelists and color fastness testing against washing using staining scale and grey scale according to SNI ISO 105-C06-2010. The results showed that the meta-mordanting technique produced the most intense and uniform color with an average panelist score of 4, higher than pre-mordanting and post-mordanting techniques. Color fastness to washing also indicated better performance with values ranging from 3 to 4. Statistical analysis using the Friedman K-Related Samples test showed a significance value of 0.000 (p < 0.05), indicating a significant difference among the mordanting techniques. These findings suggest that the meta-mordanting technique is the most effective method for improving dye absorption and color stability in cotton fabrics dyed with tingi bark extract, supporting its potential application in sustainable textile dyeing processes.
creator: Atina Khoiron Nisa
creator: Aminatur Rosyidah
rights: Copyright (c) 2026 Atina Khoiron Nisa, Aminatur Rosyidah https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 54
ending page: 61
doi: 10.36526/jc.v8i1.6848

POTENSI TEMPURUNG KELAPA DAN KULIT JENGKOL SEBAGAI BAHAN ALTERNATIF BRIKET BIOPELLET DENGAN PEREKAT TEPUNG TAPIOKA UNTUK ENERGI TERBARUKAN
type: item
description: The global energy demand continues to rise, while dependence on fossil fuels such as LPG remains high, leading to resource depletion and increased greenhouse gas emissions. This study aims to explore the potential of coconut shell and jengkol peel as alternative raw materials for biopellet briquettes using tapioca flour as a binder, in support of renewable energy development. The methods included carbonization of raw materials, formulation of briquettes with varying ratios of coconut shell to jengkol peel (TK1 : KJ3, TK2 : KJ2, TK3 : KJ1) and binder concentrations (20%, 30%, 40%), followed by characterization based on moisture content, ash content, density, calorific value, compressive strength, and Energy Performance Index (EPI). Results showed that briquettes with a 2:2 ratio and 20% binder exhibited the best overall performance, with a calorific value of 11,794 cal/g, density of 0.987 g/cm³, moisture content of 7.258%, ash content 5,602 %, and an EPI of 1.604. These values meet or approach the Indonesian National Standard (SNI 01-6235-2000) for charcoal briquettes. The study concludes that coconut shell and jengkol peel are viable materials for biopellet production, offering a sustainable and environmentally friendly energy alternative.
creator: Dini Aulia Sari Ermal
creator: Cici Maarasyid
creator: Viona Aulia Rahmi
creator: Lisa Legawati
creator: Muhammad Yusri
creator: Vriska Febiandini
rights: Copyright (c) 2026 Dini Aulia Sari Ermal, Cici Maarasyid, Viona Aulia Rahmi, Lisa Legawati, Muhammad Yusri, Vriska Febiandini https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 62
ending page: 72
doi: 10.36526/jc.v8i1.6906

DETERMINATION OF LEAD (PB) CONTAMINATION IN LETTUCE (Lactuca sativa L.) FROM VARIOUS COLLECTION SOURCES IN BANDA ACEH, INDONESIA
type: item
description: Lettuce (Lactuca sativa L.) is a vegetable that is often consumed fresh, therefore the safety of its contents needs attention, especially regarding contamination with the heavy metal lead (Pb). This study aims to analyze Pb levels in lettuce obtained from the supermarket, traditional market, and local garden in Banda Aceh City using the Atomic Absorption Spectrophotometry method (AAS) and to evaluate differences in Pb content based on the source of acquisition. The analytical method was validated through linearity, sensitivity, and precision. The Pb calibration curve shows a good linear relationship with a coefficient of determination (R²) value of 0.9931. The limit of detection (LOD) and limit of quantification (LOQ) values were 0.162 mg/L and 0.492 mg/L, respectively. The precision test at low concentrations yielded a %RSD value of 4.91%, which met the method validation criteria. The results of the analysis showed that the Pb content in lettuce from the supermarket, traditional market, and local garden was 2.54 ± 0.12 mg/kg, 2.60 ± 0.07 mg/kg, and 2.38 ± 0.08 mg/kg, respectively, all of which exceeded the maximum Pb contamination limit according to BPOM (0.2 mg/kg). The one-way ANOVA test showed that there was no statistically significant difference (p > 0.05) between Pb levels among the different sources.
creator: Muhammad Afifi
creator: Suprida Suprida
creator: Agnia Purnama
creator: Ruhul Maghfirah
creator: Mutia Farida
rights: Copyright (c) 2026 Muhammad Afifi, Suprida Suprida, Agnia Purnama, Ruhul Maghfirah, Mutia Farida https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 73
ending page: 80
doi: 10.36526/jc.v8i1.7164

PENGARUH KONSENTRASI AKTIVATOR KOH PADA KUALITAS KARBON AKTIF DARI KULIT SINGKONG
type: item
description: The aim of the research was to examine the effect of varying KOH concentrations on the properties of activated carbon produced from cassava peel waste. Cassava peel can produce activated carbon or charcoal as a result of the activation process using a physicochemical method utilizing chemical activators and chemical activation to obtain a high level of biomaterial composition and carbon content. Cassava peel charcoal will be soaked with a chemical activator (KOH) for 24 hours using different KOH concentrations, namely 1%, 2.5%, 5% and 10%. The properties of the activated carbon produced are determined by SNI No. 06-3730-1995. Tests will be carried out on iodine absorption capacity, water content and ash content as part of this characterization test. The results of this study indicate that the activated carbon produced from all treatments of KOH concentrations of 1%, 2.5%, 5% and 10% do not meet the SNI No. 16-3730-1995 standards for fixed carbon content (> 25%), volatile matter (< 65%) or iodine absorption capacity (< 750 mg / g). Activated carbon produced using 5% KOH had the best absorption capacity of 354.43 mg/g compared to the other three concentrations.
creator: Mahirullah
creator: Afrianti S. Lamuru
creator: Rosalin
creator: Suriadi
creator: Nurfiansyah
creator: Nangsih Sulastri Slamet
creator: Hasni
rights: Copyright (c) 2026 Mahirullah, Afrianti S. Lamuru, Rosalin, Suriadi, Nurfiansyah, Nangsih Sulastri Slamet, Hasni https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 81
ending page: 88
doi: 10.36526/jc.v8i1.6780

PENGARUH DOPING CUO DAN ZAT ADITIF MONOETHANOLAMINE (MEA) PADA SINTESIS TIO2 MENGGUNAKAN METODE SOL-GEL TERHADAP BAND GAP ENERGY
type: item
description: Titanium dioxide (TiO₂) is a semiconductor material that is widely used for photocatalytic applications, but it has a relatively large band gap value so that its activity in the visible light region is limited. This study aims to analyze the effect of CuO doping and the addition of monoethanolamine (MEA) additives on the band gap value of TiO₂ synthesized by the sol-gel method. CuO doping was carried out using CuCl₂·2H₂O precursor with concentration variations of 5%, 10%, 15%, 20%, and 25%. The optimum concentration was then combined with variations in MEA volume of 1 mL, 2 mL, and 3 mL. The synthesized material was characterized using UV-DRS and the band gap value was calculated using the Kubelka-Munk approach. The results of the study showed that the addition of CuO doping caused a decrease in the band gap value of TiO₂ from 3.33 eV to 3.29 eV at an optimum concentration of 15%. The addition of MEA further reduced the band gap, with the lowest value being 3.27 eV at 3 mL MEA volume. This decrease indicates that CuO doping and MEA additives play a role in modifying the electronic structure of TiO₂, thereby narrowing the energy band gap. Thus, the combination of CuO and MEA doping has the potential to enhance the optical response of TiO₂ in the visible light region, namely the range 400 – 800 nm
creator: atifaturahmah
creator: Hary Sanjaya
creator: Trisna Kumala Sari
creator: Fajriah Azra
rights: Copyright (c) 2026 atifaturahmah, Hary Sanjaya, Trisna Kumala Sari, Fajriah Azra https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 89
ending page: 95
doi: 10.36526/jc.v8i1.7415

EKSTRAKSI DAN KARAKTERISASI PEKTIN DARI LIMBAH KULIT JERUK (CITRUS SINENSIS (L.)) SEBAGAI MATERIAL POTENSIAL ADSORBEN
type: item
description: Orange peel waste (Citrus sinensis (L.)) is a promising biomass source of pectin for functional materials. The purpose of the research is to extract and analyze pectin from orange peel waste as a potential adsorbent. This work uses an environmentally friendly acid hydrolysis extraction process to prepare adsorbent materials. The extraction was carried out for 45 minutes at 95 °C in a 10% citric acid solvent (pH 1.5). Organic acid was chosen to reduce the breakdown of pectin into pectic acid while simultaneously acting as a cross-linker. The results indicated a yield of 2.545% ± 0.035%. FTIR analysis verified the existence of particular pectin functional groups, including hydroxyl (O-H) vibrations at 3359.78 cm⁻¹, carbonyl (C=O) at 1713.11 cm⁻¹, and C-O ether at 1096.70 cm⁻¹, which is similar to commercial pectin. The abundance of active groups in pectin suggests that the extracted pectin has a great potential for synthesis into porous materials like hydrogels. These materials are designed to act as adsorbents for contaminants in water via physisorption and chemisorption mechanisms, providing green chemistry-based environmental management solutions.
creator: Rifa Fazira Rizki
creator: Muhammad Reza
rights: Copyright (c) 2026 Rifa Fazira Rizki, Muhammad Reza https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 96
ending page: 106
doi: 10.36526/jc.v8i1.7323

GC–MS CHARACTERIZATION OF FATTY ACID ALKYL ESTERS IN BIODIESEL PRODUCED FROM WASTE COOKING OIL
type: item
description: This study aims to identify and characterize the major compounds in biodiesel produced through the transesterification of vegetable oils using Gas Chromatography–Mass Spectrometry (GC–MS). The analysis was conducted to evaluate the composition of fatty acid esters—specifically Fatty Acid Methyl Esters (FAME) and Fatty Acid Ethyl Esters (FAEE)—which play a crucial role in determining biodiesel quality. Three biodiesel samples were analyzed, revealing dominant peaks at retention times between 15 and 17 minutes, identified as methyl palmitate (C₁₇H₃₄O₂), methyl oleate (C₁₉H₃₆O₂), and methyl stearate (C₁₉H₃₈O₂). The total content of these major esters ranged from 85% to 92%, indicating an efficient conversion of triglycerides into esters. The resulting chemical profile exhibited a balanced proportion of saturated and unsaturated compounds, providing high oxidative stability and favorable cold flow properties. These findings demonstrate that the produced biodiesel meets the requirements of international standards ASTM D6751 and EN 14214, confirming its potential as an environmentally friendly alternative fuel.
creator: Gading Bagus Mahardika
creator: Agung Prabowo
creator: Syarifuddin Oko
creator: Muh Irwan
creator: Alvyano
rights: Copyright (c) 2026 Gading Bagus Mahardika, Agung Prabowo, Syarifuddin Oko, Muh Irwan, Alvyano https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 107
ending page: 114
doi: 10.36526/jc.v8i1.6976

SUSTAINABLE LIGNIN EXTRACTED FROM BANANA STEM BIOMASS AS A FUNCTIONAL UV-BLOCKING INGREDIENT IN SUNSCREEN
type: item
description: Banana stem biomass, an abundant agricultural by-product, contains significant lignin content and offers strong potential for valorization through green extraction technologies. In this study, lignin was extracted using an environmentally friendly Deep Eutectic Solvent (DES) composed of choline chloride and citric acid and subsequently incorporated into sunscreen cream formulations at concentrations of 2%, 3%, and 4%. The photoprotective performance of the formulations was evaluated through UV–Vis spectrophotometry, while pH measurements ensured compliance with SNI 16-4399-1996. FTIR analysis was conducted to compare the structural characteristics of DES-extracted lignin with those obtained using conventional NaOH extraction. The results revealed that all lignin-based formulations effectively absorbed UVA (320–400 nm) and UVB (280–320 nm) radiation, with UV absorbance increasing alongside lignin concentration; the 4% formulation showed the strongest UV-blocking capability. All samples maintained a skin-compatible pH of approximately 6. FTIR spectra further indicated that DES-extracted lignin preserved aromatic structures more effectively than NaOH-extracted lignin. Overall, the findings highlight the potential of banana stem-derived lignin as a natural UV-blocking and antioxidant ingredient for eco-friendly sunscreen products, supporting the advancement of sustainable cosmetic innovation.
creator: Sheryl Ayesha
creator: Nanda Aurelia Salsabila S
creator: Teguh Pambudi
creator: Hasti Asfarina
creator: Hilman Imadul Umam
creator: Fajar Amelia Rachmawati Putri
rights: Copyright (c) 2026 Sheryl Ayesha, Nanda Aurelia Salsabila S, Teguh Pambudi, Hasti Asfarina, Hilman Imadul Umam, Fajar Amelia Rachmawati Putri https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 115
ending page: 125
doi: 10.36526/jc.v8i1.7005

KARAKTERISASI KIMIA DAN MORFOLOGI BIOKOKAS DARI BAGLOG JAMUR DENGAN PEREKAT LIMBAH LILIN MALAM BATIK MENGGUNAKAN FTIR DAN SEM
type: item
description: The global energy crisis caused by the depletion of fossil fuels and increasing greenhouse gas emissions has accelerated the development of biomass-based renewable energy such as biocoke. This study aims to analyze the chemical and morphological characteristics of biocoke derived from mushroom baglog with batik wax waste binder using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). Samples were used are raw mushroom baglog (M50%) and pyrolyzed baglog biochar (P50%), each mixed with 50% batik wax waste. The pyrolysis process was carried out at 350-400 °C for 3 hours in an oxygen-limited reactor. FTIR analysis revealed that M50% biocoke contained strong aliphatic C–H and O–H hydroxyl groups, indicating high moisture (7.55%) and volatile matter (41.75%). In contrast, P50% biocoke exhibited intensified aromatic C=C peaks (1588 cm⁻¹) and reduced O–H bands (3616 cm⁻¹), reflecting higher carbonization with 46.76% fixed carbon and a heating value of 27.31 MJ/kg. SEM micrographs showed a distinct morphological difference: M50% had a fibrous and highly porous structure, while P50% displayed a compact, homogeneous surface with micro-pores (1–10 µm). The combination of pyrolysis and batik wax waste addition produced biocoke with improved combustion stability, higher thermal efficiency, and lower exhaust emissions. In conclusion, pyrolysis significantly enhances the energy quality and structural stability of biocoke, while batik wax waste acts as an effective thermoplastic binder, improving particle homogeneity and calorific performance.
creator: Hamim Mahfudhillah
creator: Siti Azzahra Santika
creator: Adeecha Cinta Islamiah
rights: Copyright (c) 2026 Hamim Mahfudhillah, Siti Azzahra Santika, Adeecha Cinta Islamiah https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 126
ending page: 134
doi: 10.36526/jc.v8i1.6468

EMULGEL EKSTRAK ETANOL DAUN SUMAMBU (HYPTIS CAPITATA JACQ.) SEBAGAI KANDIDAT ANTIBAKTERI TERHADAP STAPHYLOCOCCUS AUREUS ATCC 25923
type: item
description: Hyptis capitata (sumambu) leaves are a traditional medicinal plant from the Lamiaceae family, commonly used to treat inflammation, swelling, pain, digestive disorders, fever, and wounds. The plant contains bioactive compounds such as oleanolic acid, alkaloids, terpenoids, and flavonoids, which may have antibacterial properties. To improve topical use, the leaf extract was formulated into an emulgel. This study aimed to evaluate the antibacterial activity of the emulgel containing ethanolic extract of H. capitata leaves against Staphylococcus aureus. The experimental study employed H. capitata leaves extracted by maceration using 96% ethanol. Phytochemical screening was conducted to identify active compounds, while the physical characteristics of the emulgel were assessed through organoleptic evaluation, spreadability, adhesiveness, and pH testing. Antibacterial activity was determined using the well diffusion method at extract concentrations of 5%, 10%, and 15%, and the results were analyzed descriptively. The findings indicated that the ethanolic extract contained flavonoids. Emulgels at all concentrations exhibited acceptable physical appearance and a pH suitable for topical use (pH 5–6). However, adhesiveness remained suboptimal (<4 s), and only the 15% formulation met the spreadability criterion, with a value of 5.56 cm. All emulgel concentrations demonstrated antibacterial activity against S. aureus, producing inhibition zones of 10 mm (5%), 12 mm (10%), and 14.6 mm (15%), whereas clindamycin cream (positive control) yielded a 40 mm inhibition zone.
creator: Arviani
creator: Nurul Izza Fersilia
creator: M. Fariez Kurniawan
creator: Rahma Artemisia
rights: Copyright (c) 2026 Arviani, Nurul Izza Fersilia, M. Fariez Kurniawan, Rahma Artemisia https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 135
ending page: 143
doi: 10.36526/jc.v8i1.7504

CEMARAN MIKROBA DAN KADAR AIR PADA PENYEDAP RASA ALAMI BERBAHAN DASAR TEMPE DAN UDANG EBI
type: item
description: The use of MSG in society is usually in the form of cooking spices or broth powder. In the market there are many types and brands. But now many people are starting to reduce the use of MSG, this is because they are starting to realize the dangers and side effects of excessive use of food additives. So many people are starting to shift to using natural flavorings, either derived from pure kitchen spices or natural flavorings. This research is descriptive experimental. This research began with the manufacture of natural flavorings based on tempeh and dried shrimp. Formulations were made for 2 types with different composition ratios of tempeh and shrimp. Both formulations resulting from the manufacture of natural flavorings were then tested hedonic, to obtain market preference results. Furthermore, both formulations were tested for organoleptic, water content and microbial contamination numbers in the form of total plate counts and yeast mold numbers. The purpose of this study was to create the right formulation and test the quality of water content and microbial contamination of the formulations obtained. It is hoped that this research can produce an appropriate formulation with good quality so that it can be used by the community. The conclusion of this study is that the Natural Flavoring Formula is acceptable to the public and meets the water content requirements of 3.94% and 3.96%. Meanwhile, ALT microbial contamination was 17.5 colonies/gram and 30 colonies/gram, respectively. The yeast count was 330 colonies/gram and 4050 colonies/gram
creator: Devita Yudhayanti
creator: Erna Agung Rahmawati
creator: Nurul Nafsika
rights: Copyright (c) 2026 Devita Yudhayanti, Erna Agung Rahmawati, Nurul Nafsika https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 144
ending page: 151
doi: 10.36526/jc.v8i1.7348

XYLOKETAL DERIVATIVES FROM XYLARIA SP. AS STRUCTURAL LEADS FOR DUAL MYC/BCL2 AXIS MODULATION FOR DOUBLE-HIT HIGH-GRADE B-CELL LYMPHOMA: A DOCKING-BASED INVESTIGATION
type: item
description: High-grade B-cell lymphoma with concurrent MYC and BCL2 rearrangements, known as double-hit lymphoma, shows rapid tumor growth, strong resistance to apoptosis, and poor response to current therapies, largely because available treatments fail to target both oncogenic drivers at once. This study aimed to identify potential dual modulators of the MYC/BCL2 axis by evaluating xyloketal derivatives using a structure-based pharmacoinformatic approach. A total of twenty-one natural and semi-synthetic xyloketal compounds were prepared and analyzed through molecular docking against BCL2 at the BH3-binding groove (PDB: 4MAN) and the MYC/MAX heterodimer at the leucine zipper interface (PDB: 1NKP). Binding affinity, interaction profiles, and structure–activity relationships were examined using AutoDock Vina and Discovery Studio. The results showed that Xyloketal A achieved the strongest BCL2 binding affinity (−9.1 kcal/mol) while maintaining stable interactions with the MYC/MAX interface (−7.0 kcal/mol), supported by hydrogen bonding with Arg143 and Asp108 and hydrophobic contacts within the BH3 groove. Xyloketal J displayed the highest MYC/MAX affinity (−7.4 kcal/mol) with consistent BCL2 engagement, indicating a MYC-biased but still dual-target profile. Several derivatives, including Xyloketal A, Xyloketal J, and Xyloketal B cinnamyl ether, demonstrated balanced activity across both targets. These findings confirm that xyloketal scaffolds can engage both the BCL2 hydrophobic pocket and the MYC/MAX protein–protein interface, suggesting their potential as dual-target inhibitors. This study provides a clear computational foundation for the design and optimization of multi-target therapeutics aimed at overcoming the aggressive biology of double-hit high-grade B-cell lymphoma.
creator: Rizki Rachmad Saputra
creator: Retno Agnestisia
creator: Reny Rosalina
creator: Siti Sunariyati
creator: Yohanes Edy Gunawan
rights: Copyright (c) 2026 Rizki Rachmad Saputra, Retno Agnestisia, Reny Rosalina, Siti Sunariyati, Yohanes Edy Gunawan https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 152
ending page: 160
doi: 10.36526/jc.v8i1.7402

ANALISIS BIBLIOMETRIK PENELITIAN HIDROGEL KONDUKTIF SODIUM ALGINAT DENGAN VOSVIEWER
type: item
description: This study aims to analyze research trends and scientific developments in alginate-based conductive hydrogels and their applications in sensor technology using a bibliometric approach. Data were retrieved from the Scopus database for the period 2014–2026 using the keywords “alginate,” “sodium alginate,” “alginic acid,” “hydrogel,” and “sensor.” A total of 281 publications were analyzed using VOSviewer to evaluate keyword co-occurrence, research clusters, and thematic evolution. The results show that “sodium alginate” and “hydrogel” are the main nodes in the research network, with strong linkages to topics such as biosensors, drug delivery, and wound healing. Cluster analysis identifies major research focuses, including conductive and flexible sensors, biomedical applications of alginate, and biopolymer-based sensing materials. In addition, publication trends indicate a significant increase in research output during the 2022–2024 period, reflecting growing scientific interest in this field. Overall, this study provides a comprehensive overview of the research landscape, highlighting key themes, collaboration patterns, and emerging trends in alginate-based conductive hydrogel research. These findings offer valuable insights for guiding future research directions based on observed publication trends.
creator: Tsalsa Romadona
creator: Siti Aisyah
rights: Copyright (c) 2026 Tsalsa Romadona, Siti Aisyah https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 161
ending page: 169
doi: 10.36526/jc.v8i1.7531

UJI AKTIVITAS BROMELIN DARI ANANAS COMOSUS DAN PAPAIN DARI CARICA PAPAYA TERHADAP PH MENGGUNAKAN METODE SPEKTROFOTOMETRI UV-VIS
type: item
description: Protease enzymes such as bromelain from Ananas comosus and papain from Carica papaya are cysteine ​​protease enzymes that have great potential in various applications in the food, pharmaceutical, and biotechnology industries. This study aims to characterize the activity of bromelain and papain enzymes against pH variations using a casein-based spectrophotometric method and a tyrosine standard curve. Enzyme activity is determined based on the amount of tyrosine produced from casein hydrolysis and measured at a wavelength of 280 nm. One unit of enzyme activity is defined as the amount of enzyme that produces 1 µmol of tyrosine per mL per unit reaction time. The yields of bromelain and papain enzyme extraction in this study reached 38% and 32% with protein levels of 10.04 and 21.89 mg/mL, respectively. The activity values ​​of bromelain and papain are significantly affected by changes in pH. Bromelain showed optimum activity at pH 6, amounting to 25.4 U/mL, while the activity decreased drastically at acidic pH. The papain enzyme also has an optimum activity of 17.1 U/mL at pH 6, which decreases drastically at alkaline pH. This activity pattern is consistent with the general characteristics of cysteine ​​protease enzymes, which are sensitive to changes in the ionization of their active groups. The differences in response to pH variations indicate the specific characteristics of each enzyme, influenced by the structure and conformational stability of its protein. The results of this study provide important information regarding the optimum working conditions of both enzymes as a basis for developing industrial applications based on local biological resources.
creator: Zahrotun Nafisah
creator: Dermawan Saro Halawa
creator: Eka Miranda Silaban
creator: Sonia Tri Mart Hutapea
creator: Nasa Natalia
creator: Nia Hana Pratiwi
creator: Kamelia Fahmiati
rights: Copyright (c) 2026 Zahrotun Nafisah, Dermawan Saro Halawa, Eka Miranda Silaban, Sonia Tri Mart Hutapea, Nasa Natalia, Nia Hana Pratiwi, Kamelia Fahmiati https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 170
ending page: 178
doi: 10.36526/jc.v8i1.7624

PENGARUH VARIASI POTENSIAL ANODISASI TERHADAP SIFAT OPTIK TIO2 NANOTUBE ARRAYS (TNAS) MENGGUNAKAN METODE ANODISASI DUA TAHAP
type: item
description: Advances in science and technology have increased interest in semiconductor materials at the nanoscale, especially titanium dioxide (TiO2) with its characteristic optical properties such as band gap energy and light absorption. The growth of nanotube structures using an anodization method with parameters, namely pH, temperature, electrolyte composition, anodization potential, and time. The anodization potential has a significant influence on nanotube growth, including thickness and pore diameter. However, the higher the potential, the risk of charge recombination can occur. TNAs were prepared using a two-stage anodization method using potential variations of 40 V, 45 V, and 50 V for 1 hour in the first stage and 30 minutes in the second stage. UV-Vis DRS characterization showed that the potential of 40 V (3.22 eV), potential of 45 V (3.32 eV), and potential of 50 V (3.37 eV). The optimum potential is 40 V responsive to UV light.
creator: Zahara
creator: Sherly Kasuma Warda Ningsih
rights: Copyright (c) 2026 zahara, sherly kasuma warda ningsih https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 179
ending page: 183
doi: 10.36526/jc.v8i1.7322

A LOW-COST COLORIMETRIC DETECTION OF HG2+ USING PAPER-BASED SENSOR WITH EUCLIDEAN DISTANCE APPROACH
type: item
description: Mercury (Hg) is a highly toxic heavy metal that poses significant risks to human health and aquatic ecosystems. The development of rapid and low-cost detection methods is urgently needed. In this work, the paper-based colorimetric sensor was developed by immobilizing dithizone onto Whatman No. 41 filter paper for the detection of Hg2+. The sensor utilized the color change of the sensor from green to orange with the color formation of Hg–dithizone complex. FTIR analysis confirmed the successful immobilization of dithizone with characteristic absorption of C=N and C=S vibrations. For quantification, digital images captured by a smartphone were analyzed using the Euclidean Distance (ED) approach. The sensor demonstrated a linear response in the concentration range of 1–5 mg/L (R2 = 0.991), with a limit of detection (LOD) and limit of quantification (LOQ) of 0.50 mg/L and 1.67 mg/L, respectively. Furthermore, the sensor exhibited high precision with a %RSD of 4.39%. Selectivity tests under acidic conditions confirmed that Hg2+ yielded the highest ED value compared to other metal ions such as Cu2+, Pb2+, Co2+, Ni2+, and Zn2+. This paper-based sensor provides a simple, portable, and cost-effective tool for the on-site monitoring of mercury in environmental samples
creator: Muh. Supwatul Hakim
creator: Tety Wahyuningsih Manurung
creator: Mokhamat Ariefin
creator: Dwi Hermayantiningsih
rights: Copyright (c) 2026 Muh. Supwatul Hakim, Tety Wahyuningsih Manurung, Mokhamat Ariefin, Dwi Hermayantiningsih https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 184
ending page: 190
doi: 10.36526/jc.v8i1.7434

ANALISIS KANDUNGAN TIMBAL PADA MINUMAN SUSU CAIR KEMASAN KALENG DI TONDANO MENGGUNAKAN SPEKTROFOTOMETRI SERAPAN ATOM
type: item
description: Canned liquid milk is a popular product because it is convenient, readily available, and has a long shelf life. Cans have the potential to cause lead contamination, which poses a risk to consumer health. This study aims to determine the lead Pb content in canned liquid milk. The qualitative analysis method in this study used HCl reagent, while quantitative analysis employed Atomic Absorption Spectrophotometry on the three canned liquid milk samples labeled A, B, and C. Qualitative test results indicated that all three milk samples tested positive for Pb, as evidenced by the formation of a white precipitate. Quantitative analysis results showed Pb levels of 0.014 mg/kg in sample A, 0.008 mg/kg in sample B, and 0.007 mg/kg in sample C. All samples remained below the limit specified by SNI 8984 of 2021, which is 0.02 mg/kg.
creator: Elsa Sangian
creator: Abdon Saiya
creator: Stefan Marco Rumengan
rights: Copyright (c) 2026 Elsa Sangian, Abdon Saiya, Stefan Marco Rumengan https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 191
ending page: 196
doi: 10.36526/jc.v8i1.7474

PENENTUAN INHIBITOR SELEKTIF DALAM MENGHAMBAT KERJA ENZIM SIKLOOKSIGENASE-2 dan EFEK MUTASI RESIDU ASAM AMINO SECARA IN SILICO
type: item
description: The development of selective inhibitors for Cyclooxygenase-2 (COX-2) enzymes is a strategic priority in molecular pharmacology to address the pathophysiology of inflammation without triggering gastrointestinal side effects. This report synthesizes research findings on the binding efficacy of four specific inhibitors—Celecoxib, Rofecoxib, Valdecoxib, and Etoricoxib—using an in-silico methodology based on AutoDock 4.0 docking algorithm. The primary finding reveals that Etoricoxib exhibits the highest selectivity with a ratio of 133, supported by molecular interactions at the methyl sulfone and pyridine groups. Residue mutation analysis identifies Tyrosine 385 (Y385) on COX-2 and Phenylalanine 518 (F518) on COX-1 as critical residues determining the dynamics of active site accessibility through catalytic volume change mechanisms. This report makes a significant contribution by validating computational methods as an accurate predictive tool for mapping ligand-receptor interactions on the COX-2 enzyme
creator: Aga Adi Masyhuri
rights: Copyright (c) 2026 Aga Adi Masyhuri https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 197
ending page: 203
doi: 10.36526/jc.v8i1.7471

ANALISIS KUALITAS AIR TANAH SUMUR BOR BERDASARKAN PARAMETER FISIKA, KIMIA DAN MIKROBIOLOGI DI LINGKUNGAN KAMPUS UNIVERSITAS BANGKA BELITUNG
type: item
description: Groundwater from drilled wells at Universitas Bangka Belitung serves as the primary source for hygiene and sanitation. Groundwater quality is affected by geological conditions and anthropogenic activities, which may lead to contamination. This study aims to assess the quality of water from drilled wells in the UBB campus environment based on physical, chemical, and microbiological parameters. The sampling process was carried out at three drilled well points representing the Faculty of Science and Engineering, the Canteen, and the Rectorate using the grab sampling method. Physical parameters include odor, temperature, pH, total dissolved solids (TDS), color, and turbidity, whereas chemical parameters include nitrate, nitrite, and dissolved iron (Fe). Microbiological parameters were analyzed as total coliform using the Most Probable Number (MPN) method. The results showed that most physical and chemical parameters meet water quality standards required for hygiene and sanitation purposes, although the pH values ranged from 4,89 to 5,98, indicating slightly acidic conditions. The content of nitrate, nitrite, and dissolved Fe was relatively low and did not show any indication of chemical pollution. Microbiological parameters showed total coliform values ​​<1.8 MPN/100 mL at all sampling points, practically indicating no pathogenic bacteria were detected. The quality of the drilled well water at Universitas Bangka Belitung is classified as good and suitable for hygiene and sanitation purposes, however, regular water quality monitoring still required.
creator: Devita Harijayanti
creator: Rinny Saputri
creator: Srigustina
creator: Ultami Faziati
creator: Desma Arifa
rights: Copyright (c) 2026 Devita Harijayanti, Rinny Saputri, Srigustina, Ultami Faziati, Desma Arifa https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 204
ending page: 212
doi: 10.36526/jc.v8i1.7369

SURFACE AREA DRIVEN CRYSTALLINITY CHANGES OF HYDROXYAPATITE DURING SIMULATED BODY FLUID IMMERSION
type: item
description: The bioactivity of hydroxyapatite (HA) powders is strongly influenced by surface area and crystallinity. This study evaluates the effect of surface area and Ca/P ratio on the bioactivity of HA through immersion in simulated body fluid (SBF) for 3–21 days. Structural and chemical changes were analyzed using XRD, BET, SEM–EDX, and XRF, with bioactivity assessed from XRD peak intensity at 2θ ≈ 30°, degree of crystallinity, Ca/P ratio, calcium ion concentration, and pH variation. The results show that HA maintained its crystal phase during immersion, with the degree of crystallinity varying between 82% and 96%. An initial decrease in crystallinity and peak intensity indicated early HA dissolution, followed by an increase due to apatite layer formation at intermediate immersion times. Prolonged immersion resulted in reduced crystallinity, attributed to calcium depletion and partial re-dissolution. Higher surface area accelerated calcium ion consumption and enhanced apatite formation, confirming improved bioactivity of HA in SBF
creator: Agung Prabowo
creator: Ahmad Fadli
creator: Heni Sugesti
creator: Muh Irwan
rights: Copyright (c) 2026 Agung Prabowo, Ahmad Fadli, Heni Sugesti, Muh Irwan https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 213
ending page: 220
doi: 10.36526/jc.v8i1.7420

PERBANDINGAN AKTIVITAS ANTIOKSIDAN EKSTRAK ETANOL DAUN COCOK BEBEK (Kalanchoe pinnata) DENGAN METODE DPPH DAN ABTS
type: item
description: Kalanchoe pinnata leaves are known as a medicinal plant containing secondary metabolites with potential antioxidant activity. This study aimed to compare the antioxidant activity of the ethanol extract of Kalanchoe pinnata leaves using DPPH and ABTS methods. Extraction was carried out by maceration using ethanol as a solvent from 50 g of dried leaf simplicia, yielding 7.2 g of thick extract with a yield of 14.4%. Antioxidant activity was evaluated at concentrations of 20, 40, 60, 80, and 100 ppm. The results showed that the percentage of inhibition increased with increasing extract concentration in both methods. In the DPPH method, the highest inhibition value was 51.1605% at 100 ppm, while in the ABTS method it was 47.7203%. The IC₅₀ values obtained were 93.54 ppm for the DPPH method and 103.01 ppm for the ABTS method. Based on these values, the antioxidant activity of the ethanol extract of Kalanchoe pinnata leaves was categorized as strong in the DPPH method and moderate in the ABTS method. In conclusion, the DPPH method showed higher antioxidant activity compared to the ABTS method. The ethanol extract of Kalanchoe pinnata leaves has the potential to be developed as a natural antioxidant source in pharmaceutical and functional food applications.
creator: Boima Situmeang
creator: Weny JA Musa
creator: Nurhayati Bialangi
creator: Nani Yulianti
rights: Copyright (c) 2026 Boima Situmeang, Weny JA Musa, Nurhayati Bialangi, Nani Yulianti https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 221
ending page: 228
doi: 10.36526/jc.v8i1.7746

PENGARUH PENGGUNAAN KALIUM HIDROKSIDA DAN ASAM FOSFAT TERHADAP AKTIVITAS AMPAS KOPI DALAM PENGOLAHAN MINYAK JELANTAH
type: item
description: Coffee grounds contain various components, namely total carbon with a content of 47.8-58.9%, total nitrogen 1.9-2.3%, ash 0.43-1.6%, and cellulose as much as 8.6%. The high carbon content in coffee grounds makes it suitable for use in the manufacture of activated carbon. In this study, the utilization of coffee grounds is increased as an adsorbent by processing it into activated carbon material. Chemical carbon activation can use acidic, basic, or salt chemicals such as hydrogen chloride (HCl), phosphoric acid (H3PO4), potassium hydroxide (KOH), potassium carbonate (K2CO3), and zinc chloride (ZnCl2). In this study, KOH and H3PO4 were used as activated carbon activator compounds in coffee grounds. To determine the level of ability of potassium hydroxide and phosphoric acid as coffee grounds activators, used cooking oil was used as one of the application media. In this study, it can be concluded that the use of phosphoric acid in the coffee grounds activation process can increase the absorption capacity compared to the use of potassium hydroxide.
creator: Rika Endara Safitri
rights: Copyright (c) 2026 Rika Endara Safitri https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 229
ending page: 234
doi: 10.36526/jc.v8i1.7760

PENGARUH VARIASI KOMPOSISI TERHADAP KARAKTERISTIK BIOBRIKET BERBAHAN BAKU BIOMASSA MELALUI METODE KARBONISASI
type: item
description: Energy is classified into two groups: the first is non-renewable energy, such as coal, petroleum, and natural gas. While the second is renewable energy, for example, solar, geothermal, water, wind, and biomass. Biomass is organic material derived from plants or animals that includes wood waste such as sawdust, bark, forest residues and agricultural waste such as rice husks, straw, animal manure and others. Briquettes are categorised as solid fuels from alternative energy sources to replace fuel oil through a carbonisation process and forged through pressure with or without adhesives. This study aims to determine how the effect of composition variations on the characteristics of biobriquettes made from biomass through the carbonisation method affects calorific value, volatile matter, ash content, and water content. The experimental method is the method used in this study, with stages of material preparation, material combustion, briquette making, and briquette testing with variations of coffee grounds and rice husks, 25:75, 50:50, and 75:25. The tests carried out were proximate tests, including calorific value, water content, ash content, and volatile matter. Based on the results of research and testing of coffee grounds and rice husk briquettes, the calorific value of sample A was 2,692.66 cal/g, sample B was 3,402.81 cal/g, and sample C was 4,089.19 cal/g. The volatile matter content in sample A was 50.2921%, sample B was 64.9598%, and sample C was 83.1159%. The ash content of sample A was 43.4975%. Sample B was 29.0613%, and sample C was 14.711%. The water content in sample A was 4.3336%, sample B was 5.2663%, and sample C was 1.3438%.
creator: Meita Rezki Vegatama
creator: Eka Megawati
creator: Junety Monde
rights: Copyright (c) 2026 Meita Rezki Vegatama, Eka Megawati, Junety Monde https://creativecommons.org/licenses/by/4.0
license: https://creativecommons.org/licenses/by/4.0
date: 2026-03-31
publication date: 2026-03-31
volume: 8
number: 1
starting page: 235
ending page: 243
doi: 10.36526/jc.v8i1.7698