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KOVALEN: Jurnal Riset Kimia

kovalen
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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 325 Documents

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SINTESIS DAN KARAKTERISTIK POLIEUGENOL DARI EUGENOL MENGGUNAKAN KATALIS H2SO4 – CH3COOH Sitti Ainun Hikmah; Erwin Abdul Rahim; Musafira Musafira
KOVALEN: Jurnal Riset Kimia Vol. 4 No. 3 (2018): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Telah dilakukan sintesis polieugenol dan karakteristiknya dari eugenol menggunakan katalis H2SO4 – CH3COOH. Sintesis dilakukan dengan cara polimerisasi kationik dengan perbandingan eugenol dengan katalis H2SO4 – CH3COOH adalah 4:1. Dalam penelitian ini polieugenol diperoleh dari proses sintesis dan ditentukan berat molekulnya dengan metode viskometri serta karakteristiknya. Hasil penelitian menunjukkan berat molekul 776.247,12 g/mol. Karakteristik polieugenol berbentuk padat, berwarna coklat dengan titik leleh 84oC – 90 oC. Tidak larut dalam air, n-heksan, benzena tetapi larut dalam etanol, etil asetat dan kloroform. Produk sintesis memiliki konduktivitas 176,4 volt dengan kekuatan arus listrik 0,05 A dan 16,80 ohm.Kata Kunci : Eugenol, polimerisasi kationik, polieugenol

PEMANFAATAN KARBON AKTIF BIJI KELOR (Moringa oleifera) SEBAGAI PENYERAP LOGAM TIMBAL DALAM OLI BEKAS Hajrah Hajrah; Ruslan Ruslan; Prismawiryanti Prismawiryanti
KOVALEN: Jurnal Riset Kimia Vol. 4 No. 3 (2018): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Telah dilakukan penelitian tentang pemanfaatan karbon aktif biji kelor sebagai penyerap logam timbal dalam oli bekas.Penelitian ini bertujuan untuk menentukan kondisi terbaik dalam penurunan konsentrasi timbal (Pb) tertinggi yang terkandung dalam oli bekas. Adsorben yang digunakan adalah karbon biji kelor yang telah diaktivasi dengan asam klorida (HCl) 1 N. Pada penelitian ini menggunakan 2 variasi yaitu variasi berat adsorben dan variasi waktu kontak adsorben terhadap oli bekas. Hasil penelitian menunjukkan bahwa penurunan konsentrasi timbal tertinggi pada 5 ml oli bekas terdapat pada berat adsorben 15 gram, dan waktu kontak 3 jam. Konsentrasi timbal sebelum perlakuan adalah 2,5345 ppm dan konsentrasi sisa timbal yang didapatkan yaitu sebesar 0,3469 ppm dengan persentase penurunan konsentrasi timbal sebesar 86,31 % . Kata kunci: Adsorpsi, karbon aktif biji kelor, timbal

EKSTRAKSI DAN KARAKTERISASI PEKTIN DARI KULIT DAN DAMI BUAH CEMPEDAK (Artocarpus chempeden) Nurhaeni Nurhaeni; Nur A Atjiang; Jaya Hardi; Diharnaini Diharnaini; Khairunnisa Khairunnisa
KOVALEN: Jurnal Riset Kimia Vol. 4 No. 3 (2018): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Telah dilakukan ekstraksi dan karakterisasi pektin dari kulit dan dami buah Cempedak (Artocarpus chempedan) dengan tujuan untuk mengetahui jenis pelarut dan waktu ekstraksi terbaik yang diperlukan untuk menghasilkan rendemen pektin tertinggi. Penelitian dilakukan menggunakan rancangan acak lengkap (RAL) yang terdiri atas 2 faktor, yaitu jenis pelarut yang terdiri idar 3 taraf (asam sitrat, asam klorida, dan asam asetat) dan waktu eksraksi terdiri dari 5 taraf (30, 60, 90, 120, dan 150 menit) yang masing-masing dilakukan sebanyak dua kali pengulangan. Hasil penelitian menunjukan jenis pelarut terbaik adalah asam sitrat dengan rendemen 38,85% dan waktu terbaik diperoleh pada waktu 90 menit dengan rendemen 34,65%. Pektin yang diperoleh mengandung kadar air 5,5 %; kadar metoksil 12,4%; kadar galakturonat 71,6%; dan kadar abu 6 %.Kata Kunci : Pektin, kulit dan dami Cempedak, pelarut, waktu ekstraksi

STUDI PERBANDINGAN RENDEMEN PRODUKSI XANTOFIL DAN KAROTEN KAPANG ONCOM MERAH PADA BERBAGAI WAKTU INKUBASI Asniawati Asniawati; Ahmad Ridhay; Prismawiryanti Prismawiryanti
KOVALEN: Jurnal Riset Kimia Vol. 4 No. 3 (2018): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Telah dilakukan penelitian tentang studi perbandingan rendemen produksi xantofil dengan karoten kapang oncom merah pada berbagai waktu inkubasi. Penelitian ini bertujuan untuk mengetahui jumlah rendemen fraksi kelompok xantofil dan karoten dari berbagai waktu inkubasi kapang oncom merah pada medium tongkol jagung. Pengujian dilakukan dengan mengukur absorbansi ekstrak xantofil dan karoten pada instrumen spektrofotometer uv vis, parameter yang diamati adalah waktu inkubasi spora kapang oncom merah. Waktu inkubasi yang digunakan adalah dimulai dari hari ke 2, 3, 4, 5, 6, dan ke 7. Hasil penelitian menujukkan bahwa waktu inkubasi yang menghasilkan jumlah rendemen xantofil efektif pada hari ke 3 dengan rerata rendemen sebesar 4,435%. Sedangkan jumlah rendemen karoten efektif pada hari ke 5 dengan rerata rendemen 4,532%.Kata kunci: Xantofil, karoten, kapang oncom merah, waktu inkubasi, rendemen

AKTIVITAS ANTIBAKTERI FRAKSI n-HEKSAN, KLOROFORM, ETIL ASETAT BUNGA KAMBOJA (Plumeria alba) TERHADAP BAKTERI Staphylococcus aureus DAN Salmonella typhi ni nyoman rupiniasih; Indriani; Syamsuddin; Abdul Rahman Razak
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 2 (2019): Edisi Agustus
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Tests on the inhibition extract of n-hexane fraction, extract of chloroform fraction and extract of ethyl acetate fraction of frangipani flower (Plumeria alba) on Staphylococcus aureus and Salmonella typhi has been done. This study aims to determine the activity of frangipani flower extract on the growth of S. aureus and S. typhi bacteria. Frangipani flowers was macerated using methanol solvents. The obtained methanol extract was partitioned with n-hexane, chloroform and ethyl acetate solvents, respectively. The three extracts were tested for antibacterial activity at a concentration of 10% using the diffusion well method. The test results showed that the n-hexane, chloroform and ethyl acetate fractions showed an inhibition zone of 9.77 mm, 20.89 mm and 19.44 against S. aureus whereas S. typhi showed an inhibition zone of 15.86 mm, 27.69 mm and 21.74 mm. Keywords: Antibacterial, extract of frangipani flower, Staphylococcus aureus, Salmonella typhi.

ANALISIS KANDUNGAN NUTRISI MIE KERING YANG DISUBTITUSIKAN AMPAS KELAPA Sylvia Florensy Bawias; Syamsuddin; Prismawiryanti; Ni Ketut Sumarni
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 3 (2019): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Research has been carried out on the nutritional content of dried noodles substituted with coconut pulp. This study aims to determine the highest total protein content, highest crude fiber content and the highest water content and organoleptic quality of dried noodles substituted with coconut pulp. Dry noodles are made from wheat flour and coconut pulp as the main ingredients. The material ratio is varied to 90:10; 80:20; 70:30 and without the addition of coconut pulp flour. Dry noodles without the addition of coconut pulp flour produced the highest total protein content of 18.57%(b/b) and at the ratio of 70:30 the highest crude fiber was 17.55% (w/w) and the highest water content was 2.63% (w/w). Based on the quality of organoleptic dry noodles the most preferred is at the ratio of 90:10. Keywords: Dry noodles, coconut pulp flour, total protein content, crude fiber content, water content, organoleptic quality

STUDI ADSORPSI LOGAM Pb PADA TANAH TERCEMAR ABU TERBANG (Fly Ash) DENGAN MENGUNAKAN TANAMAN KANGKUNG DARAT (Ipomoea reptans Poir) Yul Uca Sali Putri; Khairuddin; Husain Sosidi; Dwi Juli Pusptasari
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 2 (2019): Edisi Agustus
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Pb metal adsorption studies on land water spinach (Ipomoem reptans poir) have been carried out. The method of analysis was carried out using a completely randomized design with two independent variables, i.e amount of Pb metal concentration adsorb on the roots of land spinach and the lifetime of the land spinach roots. The results show that the amount of Pb metal adsorp on the land spinach roots with variations in the age of 2-5 consecutive weeks was 0,023 µg/g; 0,03 µg/g; 0,084 µg/g; 0,099 µg/g, respectively. The results of both statistical tests, F test and LSD test, show that there was a significant difference in the concentration of Pb in each age of harvest, which in the fifth week showed the highest Pb level. BCF test results show that Pb metal adsorption takes piace with a phytoextraction mechanism. Keywords: Absorption, Lead Metal, Land Weter Spinach, Pb Levels, Length Of Planting Time

TRANSESTERIFIKASI IN SITU BIJI KELOR (Moringa oleifera Lam) MENGGUNAKAN POLIMER BERBAHAN DASAR EUGENOL SEBAGAI PENYANGGA KATALIS H2SO4 achmad rihday; Erwin Abdul Rahim; Syaiful Bahri; Dwi Juli Pusptasari
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 3 (2019): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

A study of in situ transesterification of Moringa (Moringa oleifera) seeds with polymer based on eugenol catalyst support have been carried out. The aim of the study is to determine the concentration of eugenol-based polymer support catalyst which was used to produce fatty acid methyl esters with the highest yield, and best time and to determine the composition of fatty acid methyl esters found in transesterification in situ. The results showed that the catalyst concentration of 1% with a reflux time of 150 minutes resulted in a yield of 12.04% methyl ester. The results of analysis of methyl esters using GC-MS contain methyl stearate and methyl-9,12-octadecanoate compounds. The characteristics of methyl ester are water content of 1.23%, acid number of 11.60 mgKOH/gram, saponification number of 0 mg NaOH/gram, and pour point of 16˚C. Keywords: Moringa seed, eugenol as a catalyst support H2SO4, transesterification

ANALISIS KLT BIOAUTOGRAFI EKSTRAK KULIT BATANG TANAMAN KAYU JAWA (Lannea coromandelica) TERHADAP BAKTERI Staphylococcus aureus DAN Shigella dysentriae yumita yumita; Abdul Rahman Razak; Indriani; Syaiful Bahri
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 2 (2019): Edisi Agustus
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Java wood plants (Lannea coromandelica) is a traditional medicinal plant which is still often used by people to treat internal and external wounds. The study aims to determine the effect of solvent polarity in Javanese stem bark extract on Staphylococcus aureus and Shigella dysenteriae, and to identify the compound groups which had an antibacterial activity against Staphylococcus aureus and Shigella dysenteriae with KLT-Bioautography analysis. The results show that the n-hexane extract of Javanese bark is not showing an antibacterial activity against Staphylococcus aureus and Shigella dysenteriae, whereas the ethyl acetate extract and methanol of Javanese bark show an antibacterial activity against Staphylococcus aureus and Shigella dysenteriae. The results of the TLC-Bioautography test show negative results for Staphylococcus aureus and Shigella dysenteriae. Keywords: Lannea coromandelica, antibacterial, Staphylococcus aureus, Shigella dysentriae, KLT-Bioautografi

STABILITAS EKSTRAK WARNA BUNGA ASOKA (Ixora javanica) BERDASARKAN VARIASI pH SELAMA MASA PENYIMPANAN ellditna jenianti; Nurhaeni; Pasjan Satrimafitrah; Dwi Juli Pusptasari
KOVALEN: Jurnal Riset Kimia Vol. 5 No. 2 (2019): Edisi Agustus
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Research on the potential of Ashoka (Ixora javanica) flower as a natural food and beverage coloring agent in terms of pH stability during the storage period. This study aims to determine the stability of Asoka flower extract on the effect of pH during the storage period. The time used was 10 days and the variation of pH of 2,3,4,5 and 6, respectively. The results show that Asoka flower extract was stable at pH 2 after a 10-day storage period with degradation presentation of 36.21%, while Ashoka flower extract dyes were unstable at pH 6 after a 10-day storage period with degradation percentage is 78.02%. This proves that the different acidic atmosphere influences the stability of Ashoka flower extract. Keywords : Dyes, stability of Ashoka flowers, degradation

Page 12 of 33 | Total Record : 325

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Jaya Hardi

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jr.hardi0803@gmail.com

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+6281341314717

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kovalen.journal@gmail.com

Editorial Address
Program Studi Kimia Fakultas MIPA, Uniiversitas Tadulako Jl. Soekarno-Hatta Km. 9, Tondo Palu, 94117

Location
Kota palu,

Sulawesi tengah

INDONESIA

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Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name Jaya Hardi

Contact Email jr.hardi0803@gmail.com

Phone +6281341314717

Journal Mail Official kovalen.journal@gmail.com

Editorial Address Program Studi Kimia Fakultas MIPA, Uniiversitas Tadulako Jl. Soekarno-Hatta Km. 9, Tondo Palu, 94117

Location Kota palu, Sulawesi tengah INDONESIA

Abstract

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Abstract

Contact Name
Jaya Hardi

Contact Email
jr.hardi0803@gmail.com

Phone
+6281341314717

Journal Mail Official
kovalen.journal@gmail.com

Editorial Address
Program Studi Kimia Fakultas MIPA, Uniiversitas Tadulako Jl. Soekarno-Hatta Km. 9, Tondo Palu, 94117

Location
Kota palu,

Sulawesi tengah

INDONESIA