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Jaya Hardi
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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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PENGARUH JENIS ASAM ALAMI TERHADAP PENURUNAN KADAR LOGAM BERAT TIMBAL DALAM DAGING IKAN TERI (Stelophorus indicus Sp) ASAL TELUK PALU Yulita Nelin Sipa; Jamaluddin Jamaluddin; Ihwan Ihwan
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 3 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

Research on the effect of type natural acid against decline of content heavy metals plumbum in meat anchovy (Stelophorus indicus Sp) origin bay Palu. The purpose of this study was to determine the best type of acid used in dissolving levels of plumbum as heavy metals for 1 hour immersion and to determine the number of levels of heavy metals of lead that can be dissolved during immersion 1 hour. This study begins with a sample digestion using nitric acid, further qualitative test reagents dithizon 0.005% (positive), potassium iodide (positive) and sodium carbonate (postitif). Qualitative results test that showed a positive result then measured in metal content of plumbum  using atomic absorption spectrophotometer (AAS) at λ 283.3 nm. Then soaking using tamarind are 5%, acetic acid 10%, the filtrate pineapple 100%, starfruit 100% and lime 25% for 1 hour at room temperature, after measuring the metal content of plumbum with atomic absorption spectrophotometer (AAS) in λ 283.3. The results show levels of heavy metals plumbum before immersion average of 0.8 mg/kg, the average concentration of heavy metals plumbum after soaking tamarind 5% amounting to 0.787 mg/kg (1.64%), 10% acetic acid at 0.789 mg/kg (1.39%), pineapple filtrate 100% of 0.7882 mg/kg (1.49%), starfruit 100% 0.789 mg/kg (1.39%) and lime 25% of 0.7916 mg/kg (1.06%). Thus tamarind 5% is the best type of acid to reduce levels of plumbum metal in Palu bay anchovy origin.Keywords: Acid, Anchovy (Stelophorus indicus Sp), Content, Plumbum
PENGGUNAAN SELULOSA-DIETILENTRIAMINA SEBAGAI LAPISAN PENGIKAT LOGAM Cu(II) DENGAN METODE GRADIEN DIFUSI DALAM FILM TIPIS Khairuddin Khairuddin; Dwi Juli Puspitasari
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 3 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

This researh aims to application of cellulose-diethylenetriamine as a binding layer on the diffusive gradients in thin films method with modification of cellulose with diethylenetriamine. The method of diffusive gradients in thin films in principle uses  a simple instrument such as round plastic with a diameter of 2.5 cm, which is filled with metal binding gel, diffusive gel, and membrane filter of       0.45 µm. The metal ions were diffuse through the membrane filter and diffusive gel according to the Fick's Law I, and then is accumulated in the binding layer gel. Based on the results of FTIR analysis, the formation of the binders of the copper ions at the binding layer of cellulose-dietilentriamina involves amine and hydroxyl functional groups.The results of the application of cellulose- diethylenetriamine using as binding layer with polyacrylamide diffusive gel showed a liniar concentration up to 12 hours of contact time and initial copper ion concentration up to 1000 mg/L. The maximum concentration of copper was obtained at pH 4.Keywords: copper,  cellulose- diethylenetriamine, polyacrylamide gel.
KAJIAN BIOREMEDIASI PADA TANAH TERCEMAR PESTISIDA Dwi Juli Puspitasari; Kahiruddin Khairuddin
KOVALEN: Jurnal Riset Kimia Vol. 2 No. 3 (2016)
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

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Abstract

The use of pesticides to eradicate pests are an integral part in farming system. Pesticides use  to increase production and protect the production of physical defects can also cause pollution on agricultural land. The presence of pesticide residues in soil and agricultural production can cause health problems for human and animals  and even death. To overcome this problem there needs a way to degrade hazardous waste in the  environment by performing the remediation. Remediation is carried out by microorganisms fungi, bacteria and algae known as bioremediation. Bioremediation aims to transform compounds into harmless compounds with the end result are  carbon dioxide, water and biomass cells. The advantages of bioremediation are  environmentally friendly, highly efficient, low cost, can be implemented directly in the field, laboratory and combined with chemical and physical methods.Keywords: bioremediation, soil degradation, pesticides, microorganisms
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

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