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All Journal CHEMPUBLISH JOURNAL UNEJ e-Proceeding JC-T (Journal Cis-Trans): Jurnal Kimia dan Terapannya ALCHEMY Jurnal Penelitian Kimia JMM (Jurnal Masyarakat Mandiri) Warta Pengabdian CHEESA: Chemical Engineering Research Articles Jurnal Teknologi Jurnal Pengabdian Kepada Masyarakat MEMBANGUN NEGERI Journal of Biobased Chemicals (JOBC) Sewagati Bulletin of Chemical Reaction Engineering & Catalysis Indonesian Journal of Science and Education
Helda Wika Amini
Prodi Teknik Kimia, Universitas Jember
Arts Humanities Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Education Electrical & Electronics Engineering Energy Engineering Environmental Science Languange, Linguistic, Communication & Media Materials Science & Nanotechnology Physics Public Health Social Sciences Other

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Optimization of Microwave-Assisted Alkali Pretreatment for Enhancement of Delignification Process of Cocoa Pod Husk Maktum Muharja; Rizki Fitria Darmayanti; Bekti Palupi; Istiqomah Rahmawati; Boy Arief Fachri; Felix Arie Setiawan; Helda Wika Amini; Meta Fitri Rizkiana; Atiqa Rahmawati; Ari Susanti; Ditta Kharisma Yolanda Putri
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 1 Year 2021 (March 2021)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.1.8872.31-43

Abstract

In this study, the optimization of microwave-assisted alkaline (MAA) pretreatment is performed to attain the optimal operating parameters for the delignification of cocoa pod husk (CPH). The MAA performance was examined by heating the CPH solid with different particle sizes (60–120 mesh) and NaOH solution with a different sample to a solvent (SS) ratio (0.02–0.05 g/L), for short irradiation time (1–4 min). Box-Behnken Design (BBD) was utilized to optimize the percentage of lignocellulose composition changes. The results show that by enlarging particle size, the content of lignin and cellulose decreased while hemicellulose increased. By prolong irradiation time, the content of lignin and hemicellulose decreased while cellulose elevated. On the other hand, increasing the SS ratio was not significant for hemicellulose content changes. From FTIR and SEM characterization, the MAA drove the removal of lignin and hemicellulose of CPH and increased cellulose slightly. Supported by kinetic study which conducted in this work, it was exhibited that MAA pretreatment technology is an effective delignification method of CPH which can tackle the bottleneck of its commercial biofuel production. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Quantitative Structure-Activity Relationship Study of Ester-Based Ferulic Acid Derivatives Against Cervical Cancer Cell (HELA) Helda Wika Amini; Istiqomah Rahmawati; Rizki Fitria Darmayanti; Boy Arief Fachri
Journal of Biobased Chemicals Vol. 1 No. 1 (2020): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (641.554 KB) | DOI: 10.19184/jobc.v1i1.109

Abstract

Quantitative structure-activity relationship (QSAR) has been studied for ferulic acid derivatives to determine the QSAR model able to predict anticancer. As the subject of this research was a set of experimentally calculated IC50 value data of 6 ferulic acid derivatives against cervical cancer cells (HELA). QSAR analysis was based on multilinear regression calculation on fitting subset using log (1/IC50) as the dependent variable, and dipole moment, partition coefficient in the n-octanol/water, and atomic net charges of the aromatic carbons as independent variables. The values of the descriptors were obtained from semiempirical PM3 quantum mechanic calculation. The relationship between log (1/IC50) and the descriptors was described by the result in the QSAR model. The QSAR model for ferulic acid derivatives against HELA cell lineswas developed with the statistical parameters of R=0.998; R2=0.999; SE=0.00857; and F=394. The calculated log (1/IC50) using QSAR Hansch Model for ferulic acid derivatives have excellent agreement with experimental data of Log (1/IC50).
Extraction Method of Ultrasound-Assisted Extraction (UAE) of Robusta Coffee Skin Waste using 96% Ethanol Solution in Tanah Wulan Village, Maesan District, Bondowoso Regency Miftakhul Ulum; Fitriah Novita Sari; Helda Wika Amini; Hanggara Sudrajat
Journal of Biobased Chemicals Vol. 2 No. 2 (2022): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/jobc.v2i2.270

Abstract

Argopuro Mountains, Tanah Wulan Village, Maesan District, Bondowoso Regency, East Java, Indonesia is one of the Robusta coffee-producing areas. Robusta coffee beans that are processed can produce quite a lot of by-products in the form of underutilized waste. It is known that coffee skin waste still has a lot of remaining content and it is possible to take these bioactive compounds using extraction methods. Bioactive compounds in natural materials can be done by extraction. Extraction is the process of separating substances in a sample based on different solubilities. The extraction method used is the ultrasonication method (nonconventional). Extraction of the ultrasonication method only requires a relatively shorter time with the help of an ultrasonicator. There is a lot of content in the coffee skin waste powder that needs further testing. The results of this study are expected to provide economic value to robusta coffee husk waste.
Extraction of Phenolic Active Compounds from Coffee Leaves (Coffea sp.) Using the Ultrasound Assisted Extraction Method and Total Phenol Analysis Alfinaini, Nur Aini Dwi Alfinaini; Boy Arief Fachri; Pratamai Shelli; Helda Wika Amini; Istiqomah Rahmawati
Journal of Biobased Chemicals Vol. 3 No. 1 (2023): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/jobc.v3i1.278

Abstract

Coffea sp. is one of the largest plantation commodities in Indonesia, especially coffee leaves containing phenolic compounds. This research was conducted to extract phenolic compounds using the Ultrasound-Assisted Extraction method with ethanol solvent which aims to determine the optimum operating conditions of extraction as well as the influence of variations in amplitude, time, and ratio of solvents produced. The experimental design was carried out using Design Expert 13 software with the response surface method box-Behnken design. The research variables used were amplitude variations (50%, 60%, and 70%), time (10, 20, and 30 minutes), and solvent ratios (0.1; 0.15; and 0.2 g/mL).Based on our study, these parameters affect the total phenolic content. The model equation for the total phenolic content of coffee leaves obtained is Y = 0.1349 – 0.0016 A – 0.0505 B + 0.0010 C + 0.0018 AB + 0.0043 AC – 0.0018 BC – 0.0004 A2 + 0.0178 B2 – 0.0014 C2 (R2 = 0.9758) with the optimum total phenolic content located in the 17th running of 0.209 mg GAE/g under conditions of 20 minutes, the ratio of material to solvent is 0.2 g/mL, and an amplitude of 50%.
A Evaluation of the Effect of Microalgae Chlorella vulgaris on the Performance of Membrane Bioreactor for Industrial Wastewater Treatment Faqih, Hana; Raygita May Hastuti; Zuhriah Mumtazah; Helda Wika Amini; Meta Fitri Rizkiana
Journal of Biobased Chemicals Vol. 3 No. 2 (2023): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/jobc.v3i2.428

Abstract

Water pollution, especially from industry, is a problem that continues to emerge and even get worse. Rising sludge events often occur in industrial wastewater treatment processes. Process engineering with the addition of microalgae is proposed in this study to overcome the occurrence of rising sludge and improve wastewater quality based on dissolved oxygen levels. The control variables used were MLSS 1000 mg/L, microalgae Chlorella vulgaris 106 L, and urea and TSP 1,75 kg each. The dependent variable is rising sludge and DO levels while the independent variable is time. This research went through several stages, namely seeding microalgae, seeding microalgae into activated sludge in MBBR, experimenting with combining microalgae and activated sludge in MBBR, and installing ultrafiltration membranes with a WWTP capacity of 150 m3/day. The addition of microalgae in the MBBR process has a positive impact in improving the quality of industrial wastewater, which is characterized by the absence of rising sludge and DO levels exceeding the minimum threshold.
Kinetika Ekstraksi Biji Kopi Arabika (Coffea Arabika) Lailatul Fatma; Nabilah Lu’aili Fauziah; Zuhriah Mumtazah; Helda Wika Amini; Boy Arief Fachri
Journal of Biobased Chemicals Vol. 4 No. 2 (2024): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/jobc.v4i2.1325

Abstract

Biji kopi merupakan bibit tanaman kopi dan sumber minuman kopi. Biji kopi arabika mengandung minyak yang memiliki banyak manfaat. Proses ekstraksi minyak (zat terlarut) pada kopi dapat dilakukan melalui ekstraksi pelarut (leaching). Proses ekstraksi minyak biji kopi menggunakan n-heksana sebagai pelarut karena dapat melarutkan senyawa-senyawa yang mempunyai sifat yang sama. Tujuan dari penelitian ini adalah untuk mempelajari ekstraksi minyak atsiri dari biji kopi arabika dan mengetahui model kinetika ekstraksi minyak atsiri dari biji kopi arabika dengan cara leaching. Proses pemisahan minyak kopi dan pelarut menggunakan analisis termogravimetri dengan suhu 80℃ hingga massa sampel konstan. Variabel yang digunakan adalah suhu dan waktu. Waktu ekstraksi adalah 2 jam dengan waktu pengambilan setiap 10 menit. Suhu yang digunakan adalah 30°, 40°, dan 50℃ dengan perbandingan bahan dan pelarut 1:10. Hasil penelitian menunjukkan bahwa kinetika ekstraksi kopi arabika mengikuti model kinetika ekstraksi orde dua. Nilai parameter kinetika orde kedua ekstraksi minyak atsiri kopi arabika yaitu kapasitas ekstraksi (Cs) pada suhu 30°, 40°, dan 50℃ masing-masing sebesar 5,45836, 5,46, dan 5,46001 g L-1, laju reaksi awal. ekstraksi (h) sebesar 0,00762718, 0,00756716, dan 0,0104452 gL-1menit-1, konstanta laju ekstraksi (k) sebesar 0,000256, 0,000254, dan 0,00035 g-1L-1menit-1 , dan nilai determinasi sebesar 0,9965, 0,9967 dan 0,9983.
Ekstraksi Senyawa Bioaktif Kulit Kopi dengan Pelarut Aseton Menggunakan Metode Microwave Assisted Extraction dan Analisis Senyawa Fenoliknya Julieta, Theressa; Helda Wika Amini; Ansori Ansori; Yukti Nurani; Ratri Sekaringgalih; Sonya Hakim Raharjo; Merymistika Yufrani Afred
Journal of Biobased Chemicals Vol. 4 No. 2 (2024): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/jobc.v4i2.1357

Abstract

Dewasa ini, pemanfaatan kulit buah kopi hanya terbatas sebagai pakan ternak dan pupuk. Maka dari itu, dilakukan penelitian dengan memanfaatkan limbah kulit kopi robusta sebagai bahan baku penelitian. Tujuan dilakukannya penelitian ini antara lain untuk mengetahui pengaruh dari beberapa variabel dan mengetahui kondisi optimum dalam proses ekstraksi senyawa bioaktif limbah kulit kopi. Limbah kulit kopi akan diekstrak menggunakan metode Microwave-Assisted Extraction (MAE) dengan pelarut aseton, dengan beberapa variabel yaitu rasio bahan terhadap pelarut, daya microwave, dan waktu ekstraksi. Analisis identifikasi adanya kandungan senyawa fenolik kemudian juga dilakukan menggunakan spektrofotometri UV-Vis. Variabel rasio bahan, waktu ekstraksi, dan daya microwave terbukti saling berkaitan, sehingga dapat menghasilkan total fenol pada kondisi optimum. Kondisi optimum dalam proses ekstraksi senyawa bioaktif limbah kulit kopi diperoleh pada variabel rasio bahan 0,04 g/ml ; waktu 9 menit ; dan daya 300 watt, dengan hasil total fenol sebesar 8,65 GAE/g sampel.
Kinetic Extraction of Moringa Oleifera Leaves using the Microwave Assisted Extraction (MAE) Method Rizky Pratama, Reinaldi; Ghina Shofiah Adibah Khoirunnisa; Ditta Kharisma Yolanda Putri; Helda Wika Amini; Boy Arief Fachri
Journal of Biobased Chemicals Vol. 4 No. 2 (2024): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.19184/jobc.v4i2.1379

Abstract

Daun kelor (Moringa oleifera) adalah bagian dari tumbuhan yang memiliki bentuk seperti daun dengan berbagai manfaat kesehatan dan gizi yang tinggi, serta terdapat kandungan vitamin, mineral, protein, dan senyawa bioaktif, serta memiliki sifat antioksidan dan antiinflamasi. Penelitian ini bertujuan untuk mempelajari ekstrasi, mengetahui keberadaan kandungan tannin pada daun kelor dan mengetahui model kinetika ekstraksi pada ekstrak yield daun kelor meggunakan metode Microwave Assisted Extraction (MAE). Proses ekstraksi daun kelor dilakukan dengan menggunakan pelarut etanol 96% dan menggunakan metode Microwave Assisted Extraction (MAE) dapat membantu memaksimalkan rendemen ekstraksi. Proses ekstraksi dilakukan dengan variasi daya 150 watt, rasio bahan terhadap pelarut 1:15 b/v dan waktu ekstraksi 2, 4, 6, 8, dan 10 menit. Hasil penelitian menunjukkan nilai rendemen tertinggi didapatkan pada waktu ekstraksi di menit ke 10 yaitu 10,25%. Model kinetika ekstraksi yang sesuai untuk mengekstraksi senyawa tanin dari daun kelor adalah orde 2, dimana nilai R2 lebih tinggi dibandingkan orde 1 dan nilainya hampir mendekati 1.
The Optimization of Chlorophyll Extraction from Ulva Sp. with Ultrasound-Assisted Liquid Biphasic Systems Method Susilowati; Fakhri Arkaan Humaidi; Boy Fachri; Bekti Palupi; Meta Fitri Rizkiana; Istiqomah Rahmawati; Helda Wika Amini
Indonesian Journal of Science and Education Vol. 8 No. 1 (2024): Indonesian Journal of Science and Education
Publisher : Universitas Tidar

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31002/ijose.v8i1.1085

Abstract

Ulva sp. is a type of green algae that is easily found in the shallow seas of Indonesia and contains various bioactive compounds. Chlorophyll is a bioactive compound that functions as a natural dye, free radical scavenger, and antioxidant in the body. Chlorophyll extraction with conventional methods requires a relatively long time and large amount of solvent. In this research, chlorophyll extraction from Ulva sp. with the Ultrasound-Assisted Liquid Biphasic System (UALBS) method. Ulva sp. as much as 2.5 grams mixed in acetone solvent, added K2HPO4 solution, and carried out the sonification process in a dark room. The extraction process performs at a parameter range of 5-15 minutes, ratio 0.05-0.1 g/mL, and 60-100 mesh particle size. The extracted filtrate was added with petroleum ether and distilled water to form a biphasic condition. The extracted chlorophyll was analyzed with chromatography and spectrophotometry method. Antioxidant activity was analyzed using the DPPH method. The optimum result of Ulva sp. chlorophyll extraction at an extraction time of 10 minutes, the ratio of solids to solvent was 0.1, the particle size of 60 mesh produced a yield of 1.88% with chlorophyll a 20.13664%, chlorophyll b 21.58672% and total chlorophyll 41.71012%, and the percentage inhibition 45.32%.
Isotherm and Kinetics Adsorption of Ammonium using Cocopeat Biochar Activated Meta Fitri Rizkiana; Lilis Nurhasanah; Nanda Ayudiyah Andriani; Bekti Palupi; Boy Arief Fachri; Istiqomah Rahmawati; Helda Wika Amini; Endar Hidayat
CHEESA: Chemical Engineering Research Articles Vol. 8 No. 1 (2025)
Publisher : Universitas PGRI Madiun

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25273/cheesa.v8i1.22466.43-54

Abstract

Nitrogen recovery from wastewater is capable of preventing eutrophication, offering economic benefits, and reducing carbon footprint from synthetic fertilizer production. Biochar has been explored as adsorbent for ammonium (NH??) removal. Therefore, this study aimed to investigate the potential of biochar derived from cocopeat as adsorbent for NH?? removal. Cocopeat was modified by potassium hydroxide (KOH) and pyrolyzed at 500°C for 2 h to produce activated biochar. Kinetics and isotherm studies were conducted to examine adsorption mechanisms. Fourier Transform Infrared (FTIR) data showed that the resulting biochar after activation and adsorption contained hydroxyl O–H and C–O groups, while a new N–H band confirmed the interaction with NH?? ions. Biochar adsorbed NH?? ions with a maximum capacity of 0.3078?mg/g. FTIR spectra showed shifts and changes in the intensity of functional group bands, confirming the interaction between NH?? ion and the active sites on biochar surface. Adsorption followed Langmuir isotherm and pseudo-first-order kinetics model, with an optimal contact time of 5 h. These results suggested that cocopeat-based biochar had potential as an effective NH?? adsorbent.
Co-Authors Afidatul Muadifah Afred, Merymistika Yufrani Alfinaini, Nur Aini Dwi Alfinaini Ansori Ansori Ari Susanti Atiqa Rahmawati Bekti Palupi Bimo Bayu Aji Boy Arief Fachri Boy Fachri Chintha Ananda Fidia Ningrum Dini Rahmawaty Ditta Kharisma Yolanda Putri Dyah Ayu Savitri Endar Hidayat Fakhri Arkaan Humaidi Faqih, Hana Felix Arie Setiawan Fitriah Novita Sari Ghina Shofiah Adibah Khoirunnisa Gregah Pangayoman Hartanto P Hanggara Sudrajat Hanggara Sudrajat Indra Lasmana Tarigan Istiqomah Rahmawati Istiqomah Rahmawati Julieta, Theressa Kholifatur Risma Lailatul Fatma Lilis Nurhasanah Melati Dwi Pramudita Meta Fitri Rizkiana MIFTAKHUL ULUM Mizanurafi’ Ghifarhadi Prasiefa Muhammad Reza Muhammad Rizky Kurniawan Muharja, Maktum Nabilah Lu’aili Fauziah Nanda Ayudiyah Andriani Nida Ayu Salsabila Nihayah, Husnatun Nikita Meidi Nurtsulutsiyah Nurtsulutsiyah Nurul Ulya Luthfiyana Pratamai Shelli Puji Newi Diati Ratri Sekaringgalih Raygita May Hastuti Rekfa Wika Amini Rizki Fitria Darmayanti Rizki Fitria Darmayanti Rizky Pratama, Reinaldi Safira Dian Permata Sonya Hakim Raharjo Susilowati Syarifah, Ratna Dewi Tri Kurnia Astutik Wiwik Pratiwi Yakub Hendrikson Manurung Yukti Nurani Zuhriah Mumtazah