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Jaya Hardi
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Program Studi Kimia Fakultas MIPA, Uniiversitas Tadulako Jl. Soekarno-Hatta Km. 9, Tondo Palu, 94117
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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 320 Documents
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EKSTRAKSI DAN KARAKTERISASI GLUKOMANAN DARI TEPUNG BIJI SALAK (Salacca edulis Reinw.) Faradisa Anindita; Syaiful Bahri; Jaya Hardi
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

This research aims to determine the shaking time and ratio of salak seed flour : anti-solvent isopropyl alcohol to produce glucomannan extract with high yield and high quality. Glucomannan extraction process from salak seed flour is done by aquadest solvent at temperature of 95 °C with shaking speed of 700 rpm for 30, 60, 90, 120, 150, and 180 minutes. Glucomannan precipitate was gained with anti-solvent isopropyl alcohol 95% with salak seed flour : anti-solvent ratio is 1:9, 1:11, 1:13, 1:15, and 1:17 (w/v). Then research using Completely Randomized Design (CRD) at the level of 95%. The results showed the best extraction time was obtained at shaking time of 120 minutes with yield of  21.47% and the best ratio of salak seed flour : isopropyl alcohol is 1: 17 (w/v) with yield of 40.19%. Characteristics of glucomannan is a water content of 11.18%, ash content of 1.2%, and the molecular weight 2.057 x 104 g/mol.Keywords : salak seed flour, shaking time, glucomannan.
RETENSI ASAM EIKOSAPENTAENOAT (EPA) TORTILLA TEPUNG IKAN LELE SELAMA PENGOLAHAN DAN PENYIMPANAN PADA SUHU RUANG Lutvina Vitasari; Mappiratu Mappiratu; Ni Ketut Sumarni
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

A research on the retention of eicosapentaenoic acid (EPA) on theprocessing and storage of functional tortillas.This study aims to determine the retention of eicosapentaenoic acid (EPA)flour tortillas catfish during processing and storage at room temperature.The research method includes the step of making flour catfish, processing tortillas and tortilla storage at room temperature.Analysis eicosapentaenoic acid in the tortilla is done every 7 days for 56 days using Gas Chromatography.The Results obtained indicated eikosa penta enoic acid were demaged during processing tortillas with the level of demage 9,17%. Tortillas storage at room temperature for 56 days lead to demage 31,97% EPA.Keywords: Eicosapentaenoic Acid, Retention, Tortilla
KAJIAN RETENSI KAROTEN KAPANG ONCOM MERAH DARI TONGKOL JAGUNG SELAMA PENGOLAHAN DAN PENYIMPANAN MIE INSTAN FUNGSIONAL Nurakhirawati Nurakhirawati; Harianthy Aneke; Syaiful Bahri
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Has done research on carotenoids retention oncom red on the processing and storage of instant noodles functional.This study aims was to determine the level of damage carotene in the instant noodle processing and to determine the carotene retention during storage of instant noodles as well as to determine the shelf life of instant noodles at a temperature 50ºC  and 60ºC. Estimation of shelf life or expiration period using the model of reaction kinetics the treatment phase of the study include red oncom mold production, processing instant noodles and storage of instant noodles on the temperature. Analysis carotene on instant noodlesdone every 0 days to 6 days using UV-Vis spectrophotometry method in wavelength. The data obtained is used to determine the shelf life of instant noodles. The results obtained showed live carotene demage during  the processing of instant noodles is to 20g = 1,867%. For temperature 60oC for 20g = 10,208%, and determining Q10 is 2,90 and the expiration of a functional instant noodles is 122 days.Keywords : Carotene, Mie Functional, Retention carotene, Shelf life, Reaction Kinetics Model
KARAKTERISASI EKSTRAK ETANOL BUNGA TANAMAN TEMBELEKAN (Lantana camara L.) Asmi Randa Sosang; Mappiratu Mappiratu; Ruslan Ruslan
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Research on the characterization of the ethanol extract of the flowers of tembelekan (Lantana camara L) has done. This study aims are to determine: (1) the functional group and the absorption spectrum of ethanol extract of flowers tembelekan, (2) the type of eluent used for separating the colored substance ethanol extracts of flowers tembelekan by TLC, (3) absorption spectrum and FTIR extracts and results of separation preparative TLC. Achievement of the objectives is done through the ethanol extract of flowers tembelekan by maceration, followed by taking the spectrum of UV-Vis and FTIR as well as analysis by TLC. The results showed extract ethanol absorbs light at a wavelength of 330 nm which gives an indication that there is a possibility flavonoids, flavonols and flavones. Good eluent use in the separation of components using preparative TLC were eluent a mixture of butanol / acetic acid / water = 4: 1: 5 (v / v / v), which gives an indication of at least one type of compounds in the extract, such as yellow, which has a functional group the free hydroxy group, bonded hydrogen bonding and group C=O.Keywords : flower extract tembelekan , TLC , FTIR spectra
SINTESIS ETIL LAURAT DARI ASAM LAURAT MENGGUNAKAN KATALIS ASAM SULFAT PEKAT Andi Nursyafinah; Nurhaeni Nurhaeni; Erwin Abdul Rahim
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

The aims of these research are to find out the comparison of the ratio of lauric acid molar and ethanol  (m/v), the time of mixing and the best catalyst volume to produce lauric ethyl with the highest degree of esterification by using volumetric method. Synthesize of ethyl lauric from lauric acid with ethanol did by using thick sulphate acid p.a as the catalyst with comparison of lauric acid with ratio 1:3, 1:4, 1:5, 1:6, 1:7. The variation of mixing time are 1, 2, 3, 4, 5 hour. The catalyst variation are 1, 2, 3, 4, and 5 mL. This research used random variable in the confidence interval 95%. The result of this research showed that the best molar lauric acid ratio and ethanol is 1: 7 (m/v) and esterification degree is 59,701 %. The best mixing time is 5 hour, and esterification is 53,283%, While catalyst volume variation is 1 mL with esterification degree 87,611 % Keywords : Lauric Acid, Ethyl Lauric, Esterification Degree, Volumetric Method
PENGARUH VARIASI JENIS ASAM TERHADAP RENDEMEN GELATIN DARI TULANG IKAN CAKALANG (Katsuwonus pelamis) Ahmad Ridhay; Musafira Musafira; Nurhaeni Nurhaeni; Nurakhirawati Nurakhirawati; Nurul Bima Khasanah
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

The research about “The Effect of Variation of the Type of Acid on Gelatine Yield from Cakalang Fish Bone (Katsuwonus pelamis)”. The aim of this research was to determine the higher gelatine rendament using various of type of acid. This research used Completely Randomized Design (CRD), each treatment was done in duplo.The acid variation in this research were Chloride, Sulphate, Phosphoric, Acetic, Oxalate and Citrate acid respectively. The result showed that the highest rendament was 14,658% at 5% of phosphoric acid. The analysis of the treatment has fulfilled the standard. Keywords : Gelatine, Cakalang fish bone, Isolate, Yield
SINTESIS SURFAKTAN METIL ESTER SULFONAT (MES) DARI METIL LAURAT Nur Iman; Abdul Rahman Razak; Nurhaeni Nurhaeni
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Synthesis of surfactant methyl ester sulfonate (MES) of methyl laurate has been done. This study aims to determine the best mole ratio between the methyl esters of lauric acid with sulfonated agent NaHSO3 in sulfonated methyl laurate. Mole variation used in this study are 1:1; 1:1,2; 1:1,4 and 1;1,6 (v/w). Best value MES emulsion stability, acid value and the surface tension is 94,5 minutes,1.3 ml KOH/ g sample, 39.3 dyne/cm in 1:4 ratio produces. MES synthesis produced by sulfonate group shown in the FTIR spectra in the wave number around 1366.52 to 1015.30 cm. Keywords : Surfactant Methyl Ester Sulfonate, Methyl Laurate.
PRODUKSI GLUKOSA DARI JERAMI PADI (Oryza sativa) MENGGUNAKAN JAMUR Trichoderma sp. Yuli Rismawati; Syaiful Bahri; Prismawiryanti Prismawiryanti
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Research glucose production from rice straw (Oryza sativa) using Trichoderma sp. has conducted. This study aime is to determine the effect konsentrasi Trichoderma sp. And a straw fermentation of rice (Oryza sativa) against production. Research glucose levels was done using a completely randomized design (CRD) with factorial pattern 4 variation of the concentration of Trichoderma sp. (0%, 24%, 36% and 48%) and fermentation time (3, 4, 5and6 weeks), glucose levels were analyzed using DNS with UV-Visible spectrophotometry. The measurement results showed that the highest glucose levels obtained at various concentration Trichoderma sp. 36% fermentation time during the five week sthat is equal to 14.525%. There is a positive interaction between the concentration of Trichoderma sp. and the fermentation time, the best combination of time and fungal concentration of 5 weeks and 36%, respectively.Keywords : Rice straw, Trichoderma sp., Fermentation, DNS, Spectrophotometer Uv-Visibel, Glucose.
RETENSI FENOLAT BUBUR INSTAN FUNGSIONAL SELAMA PENYIMPANAN PADA SUHU RUANG Nurakhirawati Nurakhirawati; Nurhaeni Nurhaeni; Irpan Irpan
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Fenolat retention of porridge instant functional for storage at room temperature. Has been done this study aims to determine the retention of instant porridge phenolics during storage as well as to determine the shelf life of instant porridge at room temperature. Estimation of shelf life or expiration period using the model of reaction kinetics. The treatment phase of the study include purple sweet potato flour manufacture, processing, instant porridge, instant porridge and storage at room temperature. Analysis of phenolics in instant porridge be done every 7 days for 56 days using UV-Vis spectrophotometry at a wavelength of 765 nm. The data obtained is used to determine the shelf life of instant porridge. The results obtained show the retention levels of phenolics on day 0 was 100% and at day 56 was 27.911% and the expiration of a functional instant porridge is 55 daysKeywords: Phenols, functional porridge, Fenolat Retention, Shelf Life, reaction kinetics model
ANALISIS KUALITATIF KANDUNGAN FORMALIN PADA TAHU YANG DIJUAL DIBEBERAPA PASAR DI KOTA PALU Rismawaty Sikanna
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 2 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

It had been an investigation on qualitative analysis of formalin in tofu that sold in Palu markets, purpose of this study was to identifity content of formalin in samples of tofu.This identification can know with changes of the colour of the filtrate in  samples of tofu  from  pink to be brown until the colour fed off in 30 minutes.  Samples of tofu were taken from some traditional and modern markets in Palu city. The results obtained 66.7% of all of tofu samples identified content of formalin there were 6 samples with sign of M-3, T-2, T-6, T-5, M-2, and T-4, but 3 samples with sign of T-3, M-1 and T-1 not found. It was supported of texture of tofu samples. There showed that producen of tofu in Palu city is still using formalin as preservative substance in process of tofu production.Keywords: Qualitative analysis of formalin, tofu.

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