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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 11 Documents
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Search results for , issue "Vol. 3 No. 1 (2017): Edisi April" : 11 Documents clear
ADSORBSI ION Pb2+ MENGGUNAKAN ARANG AKTIF KULIT DURIAN DENGAN METODE KOLOM ADSORBSI Nurhaeni Nurhaeni; Musafira Musafira; Agus Rahmatullah
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Research has conducted using of activated charcoal from durian skin as an adsorbent of ion Pb2+ on water. This study aims to determine the effect of high adsorbent activated charcoal of durian skin and influence of adsorbent elution time. The method used in this study is SSA. The research design is applied is an RAL, with an independent variable are high adsorbent and adsorbent elution time. In this research, the variation applied adsorbent is 13.5 cm high, 18 cm, 22.5 cm, and 27 cm and variations adsorbent of the elution time are first, second, third, fourth, fifth, and sixth hour. The results showed that activated charcoal of durian’s skin 27 cm has a higher adsorption with the variation of high adsorbent with high levels of ion Pb is 80.019% and for variations in elution time adsorbent obtained the use of the first hour is more effective , Activated charcoal durian skin can be used as an adsorbent decreased levels of Pb ion in the water until the sixth hour.Keywords:  activated charcoal, adsorbent, durian skin, Pb2+.
EKSTRAKSI DAN KARAKTERISASI EKSTRAK ZAT WARNA RUMPUT LAUT (Eucheuma cottonii) Henny H. Veronika; Mappiratu Mappiratu; Ni Ketut Sumarni
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

This study was done for the following purposes: to found solution pH as an extract to result from an extract color substance with high concentration to found time of extraction which result extract with high concentration. Determination of the best eluent which can be used in the separation of pigmented compound from the extract, by using Thin Layer Chromatography (TLC) and determination of spectrum for each functional molecule. This study was done by a maceration-extraction method, determination of pH using phosphate buffer pH 5-6 and time of extraction during 1-4 hour, separation based on TLC and analysis FTIR spectrums. The result showed that ethanol extract of Eucheuma cottonii was contained the ficoeritrine compound. This extract has appeared brown yellow in acid solution and base solution with high absorbance at pH 9 and time extraction at 1 hour. Maximum absorbance from the extract was 330 nm and the best eluent in separation of this chemical by TLC preparation, it was mixture of Chloroform-Acetic Acid-Ethanol in composition of 30 : 15 : 2 (v/v/v), which indicating there were at least four compounds within the extract, two of these were coloring brown yellow and other two were colorless and it was free hydroxyl function and bind in hydrogen bound, also C=O function.Key words: Extraction, Eucheuma cottonii, buffer phospat, TLC.
PEMANFAATAN KULIT JAGUNG (Zea mays) UNTUK PRODUKSI GLUKOSA MENGGUNAKAN KAPANG Trichoderma sp. Saiful Safari; Syaiful Bahri; Nurhaeni Nurhaeni
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

This study uses corn husk for the production of glucose by fermentation with the fungus Trichoderma sp. The aim is to determine the amount of Trichoderma sp. which is the best to produce the highest glucose with a variety of heavy fungus are 6, 9, and 12 grams in 25 grams of flour corn husk. Fermentation time variation  3, 4, and 5 weeks. Determination of the glucose level with DNS method using UV-Vis spectrophotometry. The study design using RAL factorial consisting of two factors, namely the weight of the fungus and fermentation time, each factor consists of 3 levels and is done in duplicate.The results showed that high glucose levels obtained in the addition of 12 grams of fungus and fermentation time 4 weeks with a glucose level of 21.72%.Keywords: Corn husk, Trichoderma weight, Time of fermentation, Glucose
UJI AKTIVITAS ANTIOKSIDAN EKSTRAK BUAH PURNAJIWA (Kopsia arborea Blume.) DENGAN BERBAGAI PELARUT Didit Purwanto; Syaiful Bahri; Ahmad Ridhay
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Antioxidant activity of Purnajiwa (Kopsia arborea Blume.) fruit has been investigated.The fruit was extracted by various solvents such as n-hexane, ethyl acetate, and ethanol. The aim of the research is to define a class of compounds and antioxidant activity. The compounds test was conducted by the phytochemical method. The results showed that the purnajiwa fruit extract is classified as secondary metabolites of flavonoids, saponins, tannins, alkaloids, and steroids. The antioxidant activity was tested by DPPH method and the amount of antioxidant activity was characterized by IC50 values. The result indicated that the antioxidant activity (IC50) for n-hexane, ethyl acetate, and ethanol solvents is 3524.05 ppm, 316.09 ppm, and 154.89 ppm respectively.Keywords: Purnajiwa Fruit, Antioxidant, DPPH, Phytochemicals
SINTESIS O-KARBOKSIMETIL KITOSAN PADA BERBAGAI KONSENTRASI NaOH DAN SUHU REAKSI SERTA APLIKASINYA SEBAGAI ANTIBAKTERI Jaya Hardi; Nurakhirawati Nurakhirawati; Ahmad Ridhay; Musdalifah Musdalifah
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

The research about the influence of NaOH concentrations and reaction temperature to O-Carboxymethyl Chitosan (O-CMC) synthesis and it is antibacterial application was done. This research intent on detect NaOH concentration and reaction temperature that resulting of O-CMC with highest of yield, solubility, and substitution degrees, and also to find out FTIR spectrum and antibacterial activity of O-CMC. The produce of O-CMC was done by using a Completely Randomized Design (CRD) with the variation of NaOH concentration of 20%, 30%, 40%, 50%, and 60%, and also reaction temperature of 20, 30, and 40oC. The result was showed that on the NaOH concentration of 60% (w/v) and temperature of 30oC was resulted highest of yield, solubility, and substitution degrees of 41.5%, 31 g/L, and 0.67, respectively. FTIR spectrum was showed that bending vibration of primary amine (-NH2) give two bands for O-CMC. The broadest inhibition area of O-CMC (1.43 cm) was showed on Salmonella sp.Keywords: chitosan, O-CMC, substitution degree, antibacterial
KAJIAN PENGGUNAAN SERASAH DAUN KAKAO UNTUK SUBTITUSI SERBUK GERGAJI DAN DEDAK PADI SEBAGAI MEDIA TANAM JAMUR TIRAM PUTIH (Pleurotus ostreatus) Abd. Rahman Razak; Susanti Susanti; Nurhaeni Nurhaeni; Muh. Alwi
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Has done research on the study of the use of cocoa leaf litter for substitution sawdust and rice bran as a growing medium white oyster mushroom (Pleurotus ostreatus). This study aims to determine the ability of the cocoa leaf litter in substitute sawdust and rice bran as oyster mushroom media and to determine the nutrient value of the conversion of media into fruiting bodies of oyster mushrooms. Treatment comparison of leaf litter cocoa (SDK), sawdust (SG) and rice bran (DP) there are seven various ie first treatment / standard (SDK: 0 kg, SG: 5 kg, DP: 3 kg), second (SDK: 1 , 5 kg, SG: 5 kg, DP: 1.5 kg), third (SDK: 3 kg, SG: 5 kg, DP: 0 kg), fourth (SDK: 2.5 kg, SG: 2.5 kg DP: 3 kg), fifth (SDK: 5 kg, SG: 3 kg, DP: 0 kg), sixth (SDK: 5 kg, SG: 1.5 kg, DP: 1.5 kg), and seventh (SDK: 5 kg, SG: 0 kg, DP: 3 kg). The results showed that both treatments are best treated with a total weight of 181.122 g fruit.Keywords: cocoa leaf litter, white oyster mushroom
STUDI PERBANDINGAN ANALISIS VITAMIN E MINYAK SAWIT MERAH TERSAPONIFIKASI ANTARA METODE SPEKTROFOTOMETRI UV-VIS DAN KCKT Arlina Mayharty Andulaai; Ruslan Ruslan; Hardi Ys.; Dwi Juli Puspitasari
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

A research about a comparative study of spectrophotometry UV-Vis and HPLC method for the analysis of vitamin E in saponified red palm oil has been done. This research aims to compare the results of analysis using Spectrophotometer UV - Vis and HPLC to determine the concentration of vitamin E in red palm oil previously saponified and extracted. HPLC analysis was carried out using an RP-18 column and mobile phase composed a methanol and water ( 86:14 ), with a flow rate of 1 ml/min and UV detection at 290 nm. For the Spectrophotometric UV-Vis analysis, hexane was used as a solvent and the wavelength at 298,5 nm was selected for the detection. The results are the concentration of vitamin E using spectrophotometric and HPLC method was respectively 104.5 ppm and 127 ppm.Keyword: Vitamin E, Red Palm Oil, saponification, extraction, spectrophotometry Ultra Violet -Visible, High Performance Liquid Chromatography
SINTESIS KARBOKSIMETIL SELULOSA (CMC) DARI SELULOSA KULIT DURIAN (Durio zibethinus) Dini Safitri; Erwin Abdul Rahim; Prismawiryanti Prismawiryanti; Rismawati Sikanna
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

The investigation about of carboxymethyl cellulose (CMC) of Durian peel  (Durio zibethinus) cellulose has been done. The research aim is to determine the best ratio of sodium mono-chloroacetate toward cellulose and is to determine the reaction time in the synthesis of carboxymethyl cellulose of durian peel in order to obtain the highest substitution degree. The applied of ratio variations and reaction time were 5:5, 6:5, 7:5, 8:5, 9:5 grams and 1, 2, 3, 4, 5, respectively. The result showed that the best ratio of sodium mono-chloroacetate toward cellulose was 7:5 gram with yields and the substitution degree of 39.39% and 1.17, respectively. The best time reaction was found at 4 hours with yields and the substitution degree of 39.77 % and 1.2, respectively. Keywords: Durian peel, carboxymethyl cellulose, substitution degree.
APLIKASI SELULOSA BAKTERIAL-DIETILENTRIAMINA SEBAGAI LAPISAN PENGIKAT LOGAM Pb DAN Cd PADA METODE DIFFUSIVE GRADIENT IN THIN FILMS (DGT) Khairuddin Khairuddin; Prismawiryanti Prismawiryanti; Indriani Indriani
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

This research aimed to synthesis and apply of bacterial cellulose-diethylenetriamine as a binding layer on the diffusive gradients in thin films method for preconcentration of labile metal Pb and Cd in aquatic systems and sediment of Palu Bay. The results are expected to be used for the analysis of environmental contaminants aquatic pollutant/sediment replace conventional methods. DGT method easily carried into the field and sensitive to identify certain metal ions. The results showed concentration of heavy metals dissolved in seawater for Pb between 0.024 to 0.048 mg / L, while for Cd between 0.006 to 0.015 mg / L. The concentration of Pb in sediments from 7.426 to 16.043 mg / L and Cd 0.387 to 0.950 mg / L. Partial regression analysis between Pb and Cd concentrations in water with a concentration of cadmium metals Pb and Cd in the sediments showed that the concentration of heavy metals in water has a positive correlation with the concentration of Pb and Cd in the sediment.Keyword: Pb, Cd, DGT, bacterial cellulose-diethylenetriamine, Palu Bay
ANALISIS KADAR α-TOKOFEROL (VITAMIN E) DALAM DAUN KELOR (Moringa oleifera Lam) DARI DAERAH PESISIR DAN PEGUNUNGAN SERTA POTENSINYA SEBAGAI ANTIOKSIDAN Khalil Mubarak; Hasnah Natsir; Abd. Wahid Wahab; Pasjan Satrimafitrah
KOVALEN: Jurnal Riset Kimia Vol. 3 No. 1 (2017): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Alpha-tocopherol, a major vitamin E component, functions as an antioxidant that neutralizes free radicals in a living organism. Moringa oleifera Lam. leaves are rich source of carotenoids and -tocopherol. This research was aimed to determine the concentration of α-tocopherol and examine the activity of moringa leaves (Moringa  oleifera L.) crude extracts as an antioxidant. Sample used in this research were juvenile and adult moringa leaves (Moringa oleifera L), which were taken from seashore of Barru regency and highland of Soppeng regency. Extraction of the leaves was carried out by reflux method using ethanol as a solvent, and then evaporated to produce concentrated ethanol extract. Analyzes were detected at wavelenght of 510.20 nm using UV-Vis Spectroscopy, the results indicated that concentration of α-tocopherol extracted from juvenile and adult moringa leaves from seashore area were 104.52 mg/100g and 11.419 mg/100g respectively, whilst the leaves from highland area gave a concentration of 134.4 mg/100g and 114.918 mg/100g. Next, we examined the antioxidant activity of each type of leaf using DPPH (1,1-diphenyl-2-picrylhydrazyl) methods at the wavelength of 515 nm. The IC50 results data showed that ethanol extract of juvenile and adult leaves from seashore area were 172.71 μg/mL and 258.92 μg/mL respectively, and categorized as weak antioxidant. Adversely, juvenile leaves from highland area gave a result of 97.79 μg/mL and categorized as strong antioxidant; while adult leaves from the same area gave a values of 143.14 μL/mL and categorized as medium antioxidant. Vitamin E and BHT were used as control and had higher values compared to all samples.Keywords: α-tocopherol, antioxidant, Moringa oleifera leaves, DPPH, UV-Vis Spectrophotometer.

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