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Journal : KOVALEN: Jurnal Riset Kimia

PRODUKSI DAN UJI AKTIVITAS ENZIM KITINASE DARI ISOLAT BAKTERI TERMOFILIK B1211 ASAL AIR PANAS BORA Jaya Hardi; Jusman Jusman; Abdul Rahman Razak; Silva Silva
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 3 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (254.41 KB)

Abstract

This research aims to production of chitinase from thermophylic bacteria that living in Bora hot spring  and to determine of chitinase extracts activity. The research was began with rejuvenated of B1211 bacteria isolates on MSM agar media.  The B1211 isolates was used to production of chitinase extracts on MSM broth media with chitin colloidal concentration of 0.25%, 0.5%, 1%, 2%, 4% and incubation temperature of 30oC (rt), 37oC, 50oC, and 60oC for 3 days. The chitinase activity were analyzed based on N-acetyl-D-glucosamine standard. The results was showed that B1211 bacteria isolates is potential isolate for production chitinase. The highest activity of chitinase from B1211 bacteria isolates of 0.75 U/mL for chitin colloidals concentration of 1% and temperature of 60oC.Keywords : Bora, hot spring, bacteria, thermophylic, B1211 isolates, chitinase.
PENGARUH VARIASI WAKTU DAN KECEPATAN PENGADUKAN DALAM PEMBUATAN ETIL ESTER DARI MINYAK KELAPA Jusman Jusman; Bambang Setiaji; Triyono Triyono; Akhmad Syoufian
KOVALEN: Jurnal Riset Kimia Vol. 4 No. 1 (2018): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (786.017 KB) | DOI: 10.22487/kovalen.2018.v4.i1.10188

Abstract

Penelitian ini bertujuan memperoleh etil ester yang optimum. Penelitian ini diawali dengan reaksi transesterifikasi antara minyak kelapa dan etanol dengan variasi waktu dan kecepatan pengadukan. Etil ester dianalisis dengan GC dan GC-MS. Hasil transesterifikasi optimum sebesar 76,48 % diperoleh pada rasio minyak kelapa/etanol/NaOH 1:2:0,02 (100 mL : 50 mL : 2 g) dengan kecepatan pengadukan 300 rpm. Kecepatan pengadukan dan waktu reaksi berturut-turut di atas 400 rpm dan 30 menit menghasilkan rendamen etil ester di atas 80 %. Kata Kunci : minyak kelapa, transesterifikasi, variasi waktu, dan kecepatan pengadukan
KADAR PROTEIN TERLARUT DAN GULA TOTAL BISKUIT FUNGSIONAL BERAS JAGUNG (Zea mays l) FERMENTASI Stevi Evalin Mandjoro; Nurhaeni Nurhaeni; Indriani Indriani; Jusman Jusman
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 1 (2019): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (509.303 KB) | DOI: 10.22487/kovalen.2019.v5.i1.11411

Abstract

Telah dilakukan penelitian tentang kadar protein terlarut dan gula total biskuit fugsional beras jagung fermentasi. Penelitian ini bertujuan untuk mengetahui waktu fermentasi yang memiliki kadar protein terlarut dan gula total tertinggi terhadap biskuit fungsional. Variasi waktu fermentasi untuk        menentukan kadar protein terlarut dan gula total biskuit fungsional yaitu (12, 24, 36, 48 dan 60 jam). Diperoleh hasil analisis perlakuan yang terbaik terhadap biskuit fungsional adalah pada waktu      fermentasi selama 60 jam dengan kadar protein terlarut 2,274% dan kadar gula total 15,114%.      Sedangkan hasil analisis untuk uji organoleptik biskuit fungsional yaitu nilai kesukaan rasa tertinggi diperoleh pada waktu fermentasi selama 60 jam yaitu 5,4 (suka).Kata Kunci: beras jagung, fermentasi, biskuit, protein terlarut, gula total
PENENTUAN SUHU DAN pH HIDROLISIS KITOSAN DARI CANGKANG KEONG SAWAH (Pila ampullacea) TERHADAP BERAT MOLEKUL HIDROLISATNYA Nurhaeni Nurhaeni; Angriani Sambali; Pasjan Satrimafitrah; Jusman Jusman
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 1 (2019): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (815.085 KB) | DOI: 10.22487/kovalen.2019.v5.i1.11454

Abstract

Telah dilakukan penelitian tentang penentuan suhu dan pH hidrolisis kitosan dari cangkang keong sawah (Pila ampullacea) terhadap berat molekul hidrolisatnya dengan menggunakan enzim α-amilase. Penelitian ini bertujuan untuk menentukan suhu dan pH hidrolisis terbaik yang dapat menghasilkan hidrolisat kitosan dengan berat molekul yang rendah. Variasi suhu yang digunakan untuk menghidroisis kitosan dari keong sawah antara lain 300C, 400C, 500C, 600C dan 700C. Sedangkan pH hidrolisis yang diterapkan  untuk menghidrolisis kitosan dari cangkang keong sawah antara lain 4,5; 5,0; 5,5; 6,0 dan 6,5. Pengujian berat molekul hidrolisat kitosan dilakukan dengan menerapkan metode Mark-Houwink dan parameter yang diamati adalah berat molekul hidrolisat kitosan. Hasil penelitian menunjukan bahwa suhu optimum hidrolisis kitosan yaitu suhu 500C dan menurunkan berat molekul menjadi 14.488 g/mol. Sedangkan untuk pH optimum hidrolisis adalah pH 5,5 dan menurunkan berat molekul 12.850 g/mol.Kata Kunci : hidrolisat kitosan, cangkang keong sawah, enzim α-amilase
Aktivitas Antioksidan Akar Bawang Merah Lokal Palu (Allium cepa Var Aggergatum L.) dengan Berbagai Kepolaran Pelarut: Antioxidant Activity of Local Shallot Roots (Allium cepa Var Aggregatum L.) in Palu City with Various Solvent Nur Faidah; Nurhaeni; Ahmad Ridhay; Jusman; Abd. Rahman Razak; Syaiful Bahri
KOVALEN: Jurnal Riset Kimia Vol. 6 No. 3 (2020): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2020.v6.i3.13662

Abstract

Research on the antioxidant activity of the local onion roots of Palu (Allium cepa Var Aggregatum L.) with various polarity solvents has been carried out. This study aims to determine the potential of Palu local shallot root extract as an antioxidant and determine the IC50 value of the Palu local shallot root antioxidant activity. The method applied in this research is maceration using n-hexane, ethyl acetate, and ethanol. The extracts from each solvent were tested for their antioxidant activity by the DPPH method. The results of the study showed that the IC50 value in n-hexane extract, ethyl acetate extract, and ethanol extract were 579.98 ppm, 518.28 ppm 315.83 ppm and as a comparison used ascorbic acid obtained IC50 of 53.69 ppm. Based on the results obtained, the best antioxidant activity is in polar solvents (ethanol extract) compared to other solvents. Keywords: Antioxidants, roots, Palu local shallots, Allium cepa Var Aggregatum L.
Pemanfaatan Selulosa dari Rumput Gajah (Pennisetum purpureum) pada Sintesis Karboksimetil Selulosa (CMC) : [Utilization of Cellulose from Pennisetum purpureum at The Synthesis of Carboxy Methyl Cellulose (CMC) Erwin Abdul Rahim; Grace Sita Turumi; Syaiful Bahri; Jusman; Syamsuddin
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 2 (2021): Edisi Agustus
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i2.14227

Abstract

Cellulose from Pennisetum purpureum has been used as the main ingredient in the synthesis of carboxymethyl cellulose (CMC). The purpose of CMC synthesis from the cellulose of Pennisetum purpureum is to obtain CMC compounds with the best degree of substitution (DS) value and the highest yield. The study was conducted using a completely randomized design with a factorial pattern consisting of two independent variables, namely the concentration of trichloroacetic acid (10%, 20%, and 30%) and reaction time (3 and 4 hours). The results showed that the CMC with the highest DS value (0.839) was obtained using 20% trichloroacetic acid with a reaction time of 3 hours. The highest CMC yield was 30.15% which was obtained using 30% trichloroacetic acid with a reaction time of 4 hours. Keywords: Pennisetum purpureum, carboxymethyl cellulose, substitution degree.
Retensi Antosianin dari Ekstrak Daun Bayam Merah (Alternanthera amoena Voss) pada Pengolahan Mie Basah: Retention of Anthocyanin from Red Spinach Leaves Extract (Alternanthera amoena Voss) in Processing Wet Noodles Betzy Eppang; Nurhaeni; Khairuddin; Ahmad Ridhay; Jusman
KOVALEN: Jurnal Riset Kimia Vol. 6 No. 1 (2020): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2020.v6.i1.14795

Abstract

Research about the retention of red spinach leaves extract (Alternanthera amoena Voss) as a natural coloring and preservative in wet noodles has been done. The study aim is to determine the anthocyanin retention of red spinach leaves extract in the processing of wet noodles and determine the organoleptic quality of wet noodles by adding pigment red spinach leaves extract. The extraction method used the maceration method by ethanol solvent. Anthocyanin levels on an extract that obtained by using a UV-Vis spectrophotometer were 33.34%. Anthocyanin retention of red spinach leaves extract on wet noodle processing at storage times of 0, 6, 12, 18, 24, 30, 36, 42, and 48 hours was 100%, 75.87%, 75.37%, 74.95%, 74.62%, 74.12%, 73.28%, 71.70%, and 70.61%. Organoleptic quality of wet noodles that was added with extract has “like” to “really like” grade with score detail of the best color of 4.37 at 18 hours storage, whereas the odor, texture, and taste for 0 hours storage have the highest score of 4.63, 4.63, and 4.57, respectively. The wet noodles with red spinach leaves extract more preferred than the noodles without extracts. Keywords: Retention, anthocyanin, Alternanthera amoena Voss., wet noodles
Viskositas dan Aktivitas Antibakteri Sabun Cair Berbasis VCO dengan Penambahan Ekstrak Etanol Daun Kelor (Moringa oleifera) Terhadap Bakteri Patogen: Viscosity and Antibacterial Activity of VCO-Based Liquid Soap with Addition of Ethanol Extract of Moringa Leaf (Moringa oleifera) Against Pathogenic Bacteria Pasjan Satrimafitrah; Mohamad Afdal; Jusman; Abd. Rahman Razak; Ahmad Ridhay; Nov Irmawati Inda
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 1 (2022): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2022.v8.i1.15846

Abstract

This research was conducted by making VCO-based liquid soap with the addition of ethanol extract from Moringa leaves (Moringa oleifera). The purpose of this research was to determine the mass ratio of ethanol extracts of Moringa leaves and Virgin Coconut Oil (VCO) which produces soap with the highest antibacterial activity against tested bacteria. The other purpose is to determine the effect of the mass ratio against the viscosity of liquid soap. The research design used was a Completely Randomized Design (CRD) with the independent variables being the mass ratio of Moringa leaf ethanol extract and VCO which consists of five levels of 0:75 (F1), 1.5:73.5 (F2), 3:72(F3), and 4.5:70.5(F4) (w/w). The soap produced was tested for antibacterial activity againts Staphylococcus aureus, Escherichia coli, and Staphylococcus epidermidis using agar diffusion method as well as viscosity tests. The results showed that the antibacterial activity of liquid soap tends to be higher with increasing levels of ethanol extract of Moringa leaves. The liquid soap formula with the ratio of Moringa leaf ethanol extract: VCO of 3:72 (w/w) (Formula F3) had relatively higher antibacterial activity against the three tested bacteria. The inhibition zones against Staphylococcus aureus, Escherichia coli, and Staphylococcus epidermidis were 22.302 mm, 33.230 mm, and 36.490 mm, respectively, while the viscosity value of liquid soap was 47.433 cP.
Aktivitas Antibakteri Ekstrak Kulit Batang Tumbuhan Johar (Senna siamea Lam) pada Berbagai Polaritas Pelarut : Antibacterial Activity of Johar (Senna siamea Lam) Stem Bark Extract on Various Solvent Polarities Djumidar; Abd. Rahman Razak; Ahmad Ridhay; Ni Ketut Sumarni; Syamsuddin; Jusman; Nurhaeni; Erwin Abdul Rahim
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 2 (2022): August Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2022.v8.i2.15970

Abstract

Johar plant is a type of plant from the Fabaceae family which is widely used in traditional medicine such as malaria, itching and diabetes medicine. This study aims to determine the antibacterial activity of Johar stem bark extract with different levels of solvent polarity on the growth of Staphylococcus aureus and Escherichia coli bacteria and to determine the active compound class by TLC-Bioautography. The extraction of active compounds used a multilevel maceration method starting with n-hexane (non polar), followed by ethyl acetate (semi-polar) and ethanol (polar) solvents. Antibacterial activity testing was carried out by diffusion well method with a concentration variant of 25% and 50%. The results showed that n-hexane, ethyl acetate, and ethanol extract had antibacterial activity against the two test bacteria. Ethyl acetate and ethanol extract from Johar stem bark at a concentration of 50% were classified as very strong antibacterials with inhibition zone diameters against S. aureus, which were 22.02±0.84 mm and 20.16±0.23 mm, respectively. The results of the TLC-Bioautography test showed that the three test extracts had strong antibacterial activity against S. aureus and E. coli. In the n-hexane extract with n-hexane: ethyl acetate (9:1) eluent using Lieberman-Burchard spray reagent, it was suspected that triterpenoid compounds were present. In ethyl acetate extract with n-hexane: ethyl acetate (6:4) eluent and ethanol extract with chloroform: methanol (8:2) eluent using FeCl3 1% spray reagent, it was suspected that the tannin compound was present in both extracts.
Isotermal Adsorpsi Ion Tembaga (II) Menggunakan Arang Tongkol Jagung (Zea mays L.) Teraktivasi Kalium Permanganat: Isothermal Adsorption of Copper (II) Ions Using Charcoal from Corn Cobs (Zea mays L.) Activated by Potassium Permanganate Lisma Habiba; Nov Irmawati Inda; Prismawiryanti; Husain Sosidi; Ni Ketut Sumarni; Dwi Juli Puspitasari; Moh. Mirzan; Jusman
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16292

Abstract

Corn cobs which generally only become waste can be processed into activated carbon and used for the absorption of heavy metals, such as copper(II) ions. This study aims to determine the morphology of corn cobs charcoal after activation, determine the isothermal adsorption model of copper (II) metal ions on corncob-activated carbon, and then determine the adsorption capacity of copper (II) metal ions on corncob-activated carbon. The morphology of the corncob-activated charcoal obtained was analyzed using Scanning Electron Microscopy (SEM). Isothermal adsorption of copper (II) ions was carried out with various concentrations of copper (II) ions of 5, 10, 20, 50, and 100 ppm. The results of the analysis using SEM showed that the surface shape of the corncob-activated charcoal is regular and has pores with a pore diameter obtained in the range between 1.08-1.26 m and 1.38-1.59 m. The mechanism of adsorption of copper (II) ions by corncob-activated charcoal using KMnO4, following the Freundlich isothermal model with a value of R2 0.9993 with an adsorption capacity of 51 x 10-4 mmol/L. The utilization of activated carbon from corn cobs that are activated by potassium permanganate is very effective for adsorbing copper metal ion pollutants through an adsorption mechanism on the surface of activated carbon.