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All Journal KOVALEN: Jurnal Riset Kimia
Hardi Ys.
Jurusan Kimia FMIPA Universitas Tadulako
Chemical Engineering, Chemistry & Bioengineering Chemistry

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Sintesis Metil Ester Asam Lemak dari Biji Alpukat (Parsea americana Mill) Menggunakan Polimer Penyangga Katalis Berbahan Dasar Eugenol: Synthesis of Fatty Acid Methyl Ester from Avocado Seeds (Parsea americana Mill) using Polymer Support Catalyst Based on Eugenol Sumarni; Erwin Abdul Rahim; Ni Ketut Sumarni; Ruslan; Hardi Ys.; Moh. Mirzan
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.i3.13053

Abstract

Research on the manufacture of methyl esters from avocado seeds (Parsea americana Mill) with eugenol-based catalysts has been conducted. The aim is to determine the catalyst concentration used to produce methyl esters with the highest rendement and determine the composition of fatty acid methyl ester in avocado seeds. This study was used variations in concentrations of 0.25%, 1%, 1.75%, 2.25%, and 3%. The results of this study showed that the best concentration is 2.25% with the calculation of the results of 24.8% methyl esters in avocado seeds, namely lignoceric and octadecenoic acid methyl ester. Keywords: Avocado seeds, fatty acid methyl esters
Pengaruh Konsentrasi Asap Cair Terhadap Mutu, Total Bakteri, dan Waktu Simpan Ikan Cakalang (Katsuwonus pelamis) Asap: Effect of Liquid Smoke Concentration on Quality, Total Bacteria, and Shelf Life of Smoked Skipjack Fish (Katsuwonus pelamis) Angria Deswika Malambu; Syaiful Bahri; Hardi Ys.; Prismawiryanti; Abd. Rahman Razak
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): 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.2021.v7.i1.14238

Abstract

Liquid smoke contains acid, carbonyl, and phenolic compounds, so it is very appropriate to be used as a preservative. Traditional smoking can be replaced with liquid smoke because it is safer and more practical. The study of the use of coconut shell liquid smoke has been used in skipjack fish to determine the effect of liquid smoke concentration and storage time on dissolved protein content and total bacteria in smoked fish. The quality of smoked fish was determined by two treatments, namely the variation in the concentration of liquid smoke (2, 3, 4, and 5%) and storage time (2, 4, 6, 8, and 10 days). The results showed that the best concentration of liquid smoke to produce smoked skipjack fish is 3% with a water content of 62.41% and dissolved protein content of 17.58%. The maximum storage time of smoked skipjack tuna is 6 days with a total plate count (TPC) value or total bacteria 1.8 x 105.
Hidrolisis Protein Teripang Hitam (Holothuria edulis) Menggunakan Bromelin Kasar dari Batang Nanas (Ananas comocus L): Protein Hydrolysis of Black Sea Cucumber (Holothuria edulis) Using Crude Bromelain from Pineapple Stem (Ananas comocus L) Fakhrija Sahraini; Abd. Rahman Razak; Syaiful Bahri; Hardi Ys.
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 3 (2021): 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.2021.v7.i3.15689

Abstract

Black sea cucumber is one type of sea cucumber whose protein content is quite high at 74-82%, not yet widely used by the community as a source of protein. One way to use it is to process the protein into a protein hydrolyzate using the bromelain enzyme which was isolated from pineapple stems. This study aims to determine the concentration of the bromelain enzyme extract and the optimum hydrolysis time to the value of the hydrolysis degree of the hydrolyzate of black sea cucumber protein. Protein hydrolysates are produced by variations of the crude bromelain concentration of 9%, 10%, 11%, and 12% (v/v) and hydrolysis time of 120, 180, 240, and 300 minutes. The results showed that the optimum degree of hydrolysis was obtained with the use of bromelain extract with a concentration of 12% with a value of 11.43% and a hydrolysis time of 240 minutes with a value of 19.17%.
Penggunaan Karbon Aktif dari Tandan Kosong Kelapa Sawit Teraktivasi NaOH pada Penyerapan Ion Pb(II): Utilization of NaOH-Activated Carbon from Oil Palm Empty Fruit Bunches on Pb(II) Ion Absorption Minda M; Husain Sosidi; Ni Ketut Sumarni; Hardi Ys.; Ruslan; Nov Irmawati Inda; Moh. Mirzan
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.i1.15847

Abstract

Oil palm empty fruit bunches (OPEFB) are plantation waste that has the potential to be used as activated carbon. The main component of OPEFB is lignocellulosic which can be a source of activated carbon and utilized for Pb2+ ion adsorption. The use of activated carbon activated by NaOH still requires optimization, especially in determining the contact time and optimum adsorption pH. This study aims to determine the effect of pH and contact time on the adsorption of Pb2+ and to determine the efficiency of the adsorbent on the adsorption of Pb2+. In this study, activated carbon from OPEFB was carbonized at 300oC for 1 hour, followed by activation using NaOH 0.5%. The results showed that the use of pH 5 and a contact time of 90 minutes had a relatively higher Pb2+ adsorption than other conditions. However, the use of variations in pH and contact time had no significant effect on the adsorption of Pb2+ ions. Adsorbents with variations in pH 4, 5, 6, 7, and 8 were able to absorb Pb2+ of 99.73%, 99.86%, 99.74%, 99.79%, and 99.80%, respectively. Adsorbents with variations in contact time of 30, 60, 90, 120, and 150 minutes were able to absorb Pb2+ of 99.28%, 99.40%, 99.48%, 99.44%, and 99.48%, respectively.
Co-Authors Abd. Rahman Razak Angria Deswika Malambu Erwin Abdul Rahim Fakhrija Sahraini Husain Sosidi Minda M Moh. Mirzan Ni Ketut Sumarni Nov Irmawati Inda Prismawiryanti Prismawiryanti Ruslan Ruslan Sumarni Syaiful Bahri