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Jaya Hardi
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kovalen.journal@gmail.com
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Program Studi Kimia Fakultas MIPA, Uniiversitas Tadulako Jl. Soekarno-Hatta Km. 9, Tondo Palu, 94117
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INDONESIA
KOVALEN: Jurnal Riset Kimia
Published by Universitas Tadulako
ISSN : -     EISSN : 24775398     DOI : https://doi.org/10.22487/kovalen
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry
KOVALEN: Jurnal Riset Kimia is a peer-reviewed journal of chemistry published by the Tadulako University, Indonesia. This journal concern with publishing the original research articles, review articles, and the current issues related to chemistry. Publishing frequency 3 issues per year, in April, August, and December.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 13 Documents
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Search results for , issue "Vol. 8 No. 2 (2022): August Edition" : 13 Documents clear
Potensi Ekstrak Batang Kayu Gempol (Nauclea orientalis L.) dalam Menghambat Pertumbuhan Bakteri: Potency of Gempol (Nauclea orientalis L.) Stem Extracts to Inhibiting Bacterial Growth Ni Kadek Atmiyanti; Pasjan Satrimafitrah; Abd. Rahman Razak; Nov Irmawati Inda; Indriani; Dwi Juli Puspitasari
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.i2.15962

Abstract

The study of the potential of Gempol wood stem extract (Nauclea orientalis L.) with three solvent polarities has been exercised to determine the extract with a certain polarity and the smallest concentration that can inhibit the growth of bacteria Staphylococcus aureus and Escherichia coil. Extraction is performed using the maceration method with n-hexane, ethyl acetate, and ethanol as solvents. Furthermore, the potency in inhibiting the growth of bacteria was observed by the diffusion method with a range of extract concentrations from the largest to the smallest. The extract's ability to inhibit bacterial growth in the time range of up to 24 hours was measured using the turbidimetric method. The results showed that ethyl acetate and ethanol extracts were able to inhibit the growth of both bacteria in a wide concentration range (100 %– 5%), although n-hexane extracts showed the highest percentage in inhibiting both bacteria (15.27 mm and 16.89 mm, respectively). Turbidimetric assays showed the extract was stronger in inhibiting S. aureus compared to E. coli in the logarithmic phase range of 12 hours. This study showed that semipolar and polar extracts can inhibit the growth of bacteria with a wider concentration range compared to non-polar extracts despite having a higher inhibition capability.
Penurunan Kadar Chemical Oxygen Demand (COD) pada Limbah Cair Industri Tahu Menggunakan Arang Aktif dari Pelepah Kelapa Sawit (Elaeis guenensis Jacq.) : Reducing Chemical Oxygen Demand (COD) Levels in Tofu Industrial Liquid Waste Using Activated Charcoal from Palm Oil (Elaeis guenensis Jacq.) Mid-ribs Khairuddin; Ruslan Ruslan; Muh.Ricky Arisandi M. Tahili; Dwi Juli Puspitasari; Indriani; Husain Sosidi; Prismawiryanti; Moh. Mirzan
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.i2.15966

Abstract

Oil palm midribs (Elaeis guenensis Jacq.) are one of the wastes from oil palm plantations. The high carbon element composition in the palm midribs has the potential to be used as charcoal or activated carbon. Activated carbon can reduce COD levels in tofu industrial wastewater. This study aims to determine the effect of activated carbon mass and contact time on decreasing COD levels in tofu industrial wastewater. Palm midrib charcoal was activated using HCl 1N with the independent variable of activated charcoal mass (1, 3, 5, 7, and 9 grams) and contact times (30, 60, 90, 120, and 150 minutes), while the dependent variable was the percentage decrease COD levels. Activated charcoal from the palm midribs was in accordance with SNI 06-3730-1995 concerning the Quality Standard of Activated Charcoal. The effect of the adsorbent mass showed that the mass increase in activated charcoal was directly proportional to the percentage decrease in COD levels in the tofu industrial wastewater, while the optimum contact time of activated charcoal was obtained at 60 minutes with a decrease in COD levels of 82.13%.
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.

Page 2 of 2 | Total Record : 13

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