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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 325 Documents
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Pengaruh Metode Hidrolisis Terhadap Karakteristik Kimia Senyawa Kalsium Hasil Ekstraksi dari Cangkang Telur Ayam: The Effect of Hydrolysis Methods on Chemical Characteristics of Extracted Calcium Compounds from Chicken Eggshells Yurikke Julieta Permata Putri Sunarya; Yuni Kustiar; Nancy Siti Djenar; Ayu Ratna Permanasari
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.i1.15803

Abstract

Preparation of calcium compounds such as calcium hydroxide, calcium carbonate, and calcium oxide from chicken eggshells can be done through conventional methods that are cheaper and more practical, such as the sol-gel hydrolysis method and the coprecipitation method. In this study, the synthesis of calcium compounds from domestic chicken eggshells was carried out using two methods: the coprecipitation method and sol-gel method. Coprecipitation method consists of acid hydrolysis and alkaline hydrolysis. Sol-gel method consists of modification I and modification II. The AAS results showed that the calcium content from the hydrolysis of acids, alkaline, sol-gel modification I, and sol-gel modification II: 14.50%, 6.64%, 6.68%, and 9.93%, respectively. The FTIR showed that calcium compounds have four characteristic absorption bands, including O–H (3641.60 and 3448.72 cm-1) derived from Ca(OH)2 and H2O products, C=O (2981.95 - 1799 cm-1), and C–O (1448.54 – 874.68 cm-1) both of which from carbonate ions (CO3-) in CaCO3 both from eggshell and from the resulting calcium compounds, and Ca-O (711.73 cm-1) derived from CaO products. The results showed that the modification ll sol-gel method was the best because calcium compounds consisting of CaCO3, Ca(OH)2, and CaO were produced in a smooth texture, white color, and with the highest calcium content compared to other methods.
Analisis Kandungan Merkuri (Hg) pada Badan Air, Sedimen dan Biota yang Terdampak Aktivitas Pertambangan Emas di Kabupaten Parigi Moutong: Analysis of Mercury (Hg) Content in Water Bodies, Sediments, and Biota Affected by Gold Mining Activities in Parigi Moutong District Ernawaty Rasul; Musafira Musafira
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.i1.15835

Abstract

Parigi Moutong District is one of the regencies in Central Sulawesi province with the highest number of illegal mining activities. Unlicensed mining activities generally use mercury as an extracting agent and gold processing waste is generally disposed of in rivers or other water bodies. The purpose of this study was to analyze the levels of heavy metal mercury (Hg) in water bodies, sediments, and marine biota in gold mining areas in Parigi Moutong District. The sampling method was carried out by random sampling method, while the analysis of mercury content in samples of river water, sediment, and biota was carried out using atomic absorption spectroscopy (AAS). From the results of the study, it was found that mercury levels in water and sediment samples were still below the quality standard value which were 0.001 mg/Kg and 0.13 mg/Kg, respectively, while the mercury levels in all biota samples had exceeded the quality standard values ​(0.03 mg/Kg). This indicates that mercury has accumulated in the food chain in the water near the mine site.
Pembuatan Konsentrat Protein Ampas Tahu Menggunakan Garam Ammonium Sulfat: Manufacturing of Tofu Pulp Protein Concentrate Using Ammonium Sulphate Nurhaeni; Frischa Sari Kencana; Andi Tenri Ajeng; Khairuddin; Prismawiryanti; Syamsuddin; Dwi Juli Puspitasari; Indriani; Erwin Abdul Rahim
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.i1.15844

Abstract

Tofu pulp which generally becomes waste can be used as a source of protein concentrate. Protein concentrates from tofu pulp have been obtained at various ratios of tofu pulp: ammonium sulfate and ammonium sulfate salt concentration. The research was conducted to obtain the highest protein yield and content of tofu pulp protein concentrate. This study used a completely randomized design (CRD) with the independent variable being the ratio of tofu pulp filtrate: ammonium sulfate (1:2, 1:3, 1:4, 1:5, 1:6, and 1:7 (v/v)) and concentrations of ammonium sulfate (30, 40, 50, 60, 70, and 80%), while the dependent variables were the yield of protein concentrate and protein content. Production of protein concentrate used the salting-out method with ammonium sulfate salt. The ratio of tofu pulp: ammonium sulfate 70% obtained the best ratio of 1:5 with a yield of 41.6% and protein content of 84.58%. Tofu pulp as industrial waste can be a potential source of protein concentrate because it has a high protein content.
Viskositas dan Aktivitas Antibakteri Sabun Cair Berbasis VCO dengan Penambahan Ekstrak Etanol Daun Kelor (Moringa oleifera) Terhadap Bakteri Patogen: Viscosity and Antibacterial Activity of VCO-Based Liquid Soap with Addition of Ethanol Extract of Moringa Leaf (Moringa oleifera) Against Pathogenic Bacteria Pasjan Satrimafitrah; Mohamad Afdal; Jusman; Abd. Rahman Razak; Ahmad Ridhay; Nov Irmawati Inda
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.i1.15846

Abstract

This research was conducted by making VCO-based liquid soap with the addition of ethanol extract from Moringa leaves (Moringa oleifera). The purpose of this research was to determine the mass ratio of ethanol extracts of Moringa leaves and Virgin Coconut Oil (VCO) which produces soap with the highest antibacterial activity against tested bacteria. The other purpose is to determine the effect of the mass ratio against the viscosity of liquid soap. The research design used was a Completely Randomized Design (CRD) with the independent variables being the mass ratio of Moringa leaf ethanol extract and VCO which consists of five levels of 0:75 (F1), 1.5:73.5 (F2), 3:72(F3), and 4.5:70.5(F4) (w/w). The soap produced was tested for antibacterial activity againts Staphylococcus aureus, Escherichia coli, and Staphylococcus epidermidis using agar diffusion method as well as viscosity tests. The results showed that the antibacterial activity of liquid soap tends to be higher with increasing levels of ethanol extract of Moringa leaves. The liquid soap formula with the ratio of Moringa leaf ethanol extract: VCO of 3:72 (w/w) (Formula F3) had relatively higher antibacterial activity against the three tested bacteria. The inhibition zones against Staphylococcus aureus, Escherichia coli, and Staphylococcus epidermidis were 22.302 mm, 33.230 mm, and 36.490 mm, respectively, while the viscosity value of liquid soap was 47.433 cP.
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.
Determination of Mercury (Hg) and Lead (Pb) in Sedimen of Batanghari River in Dharmasraya Regency Mawardi Mawardi; Rahma Juita; Fadhlurrahman Mawardi; Kori Ariani; Nindia Novari; Irfan Ananda Ismail
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.i1.15864

Abstract

Batanghari River is a river that crosses the Province of West Sumatra and Jambi Province, which flows through the Dharmasraya Regency area. Along this river, many illegal gold mines are found, which use mercury (Hg) as a gold-binding medium, and fuel oil containing lead (Pb) as fuel for machinery used in mining operations. This mining activity is the cause of the presence of Hg and Pb in the mining environment which is passed by the Batanghari river. The source of Pb is also from tailings, which is the remaining metal ore processing that does not meet the requirements to be taken at the time of mining. the presence of Hg and Pb metals in the aquatic environment will have an impact on the environment and interfere with the health of miners and the surrounding community, because Hg and Pb are heavy metals that are toxic. Research has been carried out on the Batanghari river sediments in January and April 2019 using the Atomic Absorption Spectrophotometer (FAAS) method to measure Pb and the Cold Vapor Atomic Absorption Spectrophotometer (CV AAS) method for Hg metal. The results showed that each metal Hg and Pb, in mg metal per Kg sediment, in the range of 0.08 mg/kg – 10.21 mg/kg, and 1.81 mg/kg – 23.10 mg/kg. Based on these data, it can be said that in January and April 2019 the metal content of Hg and Pb in the Batanghari river air was above the river water quality standard according to the Government Regulation of the Republic of Indonesia, namely 0.001-0.002 mg/L for Hg and 0.03 mg/L for Pb
Potensi Minyak Herbal STIFA Pelita Mas Terhadap Kadar Ureum dan Kreatinin Tikus Kondisi Hiperglikemik: Potency of STIFA Pelita Mas Herbal Oil on Ureum and Creatinine Levels of Rats Hyperglycemic Conditions Joni Tandi; Dewi Astuti; Magfirah Magfirah; Tien Wahyu Handayani
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 2 (2022): August 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.i2.15820

Abstract

Utilization of natural preparations is a treatment carried out by the community with the aim of improving health status naturally. Traditional medicine has become an alternative for the community due to the relatively high cost of modern medicine. One of the diseases with a high financing burden is kidney disease, which is after heart and blood vessel disease. This study aims to determine the potential of traditional medicinal preparations of Herbal Oil STIFA Pelita Mas on the state of urea and creatinine concentrations in experimental animals, this research used white male rats divided into six treatments. Determination of urea and creatinine levels was carried out starting from days 1, 7, 14, 21 to 28, then normality and homogeneity tests were carried out, and parametric statistics were analyzed using the one-way ANOVA test. The results showed that the administration of STIFA Pelita Mas Herbal Oil in Formula 1, 2, and 3 had urea levels of 42.60 mg/dL, 28.64 mg/dL, and 51.46 mg/dL, respectively. The average values ​​of creatinine in Formula 1, 2, and 3 were 0.73 mg/dL, 0.63 mg/dL, and 0.92 mg/dL, respectively. The administration of Formula 2 was effective in reducing the concentration of urea and creatinine. Pelita Mas herbal oil preparation can be used as a medicine to improve kidney structure.
Identifikasi Senyawa Fraksi Larut n-Heksana Rimpang Temu Mangga (Curcuma mangga Val) Menggunakan LC-MS/MS dan Review Potensinya sebagai Antibakteri: Identification of Compounds Soluble n-Hexane Fraction of Rhizome of Temu Mangga (Curcuma mango Val) Using LC-MS/MS and Review of its Potential as Antibacterial Purwantinigsih Sugita; Risda Fardilya Nihayah; Moch Ikkbal Aditya Kasmaran; Gustini Syahbirin; Auliya Ilmiawati; Budi Arifin; Luthfan Irfana
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 2 (2022): August 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.i2.15897

Abstract

Plants are like the pharmaceutical industry that provides products that have the potential as active medicinal ingredients. In order to search for compounds useful for health, the purpose of this study was to identify secondary metabolites of Curcuma mango (temu mango) growing in the experimental garden of Biopharmaca LPPM IPB and review its activity as antibacterial. Identification begins with phytochemical screening, then separation and purification by chromatographic techniques. Intersection mango simplicia was extracted with methanol, and the crude extract of methanol was partitioned with n-hexane, ethyl acetate, and methanol, respectively. The n-hexane soluble fraction was carried out by phytochemical tests, fractionation by vacuum liquid chromatography (KCV) and radial (KR), and the selected fractions was analyzed by LC-MS/MS. The results of the phytochemical test of the soluble n-hexane fraction showed a positive presence of alkaloids and terpenoids through successive tests with Mayer, Wagner, Dragendorff (alkaloid), and Lieberman-Burchard reagents. Fractionation of the n-hexane soluble fraction with KCV resulted in 9 fractions (H1-H9) and the H5 fraction showed good separation between spots in the n-hexane: ethyl acetate eluent mixture (97:3). Purification of H5 with KR obtained 7 fractions (H5.1-H5.7). Based on LC-MS/MS, the H5.2 fraction was dominated by the terpenoid group, and the results of the literature review showed the contribution of terpenoids as antibacterial compounds
Delaminasi Perekat Polivinil Asetat Berbasis Air Satu Komponen untuk Aplikasi Kayu Keras Ulin dan Merbau: Delamination on Polyvinyl Acetate Water Based Adhesive One Component for Ulin and Merbau Hard Wood Working Application Retno Indarti; Agustinus Ngatin; Robby Sudarman; Tifa Paramitha; Rony Pasonang Sihombing
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 2 (2022): August 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.i2.15900

Abstract

Water-based adhesive was one of the most important media for bonding substrates to one another because of their environmental friendly character. Previously, in the application of hardwood adhesives such as Ulin and Merbau, the type of adhesive used was a two-component system. For this reason, a one-component water-based adhesive was introduced in this study. The advantage of these was environmental friendly and high durability. In this application, delamination was one of the important parameters to determine whether the adhesive used was well penetrated or not. For this reason, delamination will be the main parameter in this study. This research includes the preparation of tools and materials, manufacture of PVA (polyvinyl alcohol) solution, polymerization of polyvinyl acetate by mixing the main raw material of vinyl acetate monomer and PVOH solution using APS (ammonium persulfate) initiator. The polymerization process was carried out at 1 atm pressure and 75oC – 80oC temperature accompanied by stirring with ±500 rpm rotation rate. Final product is a homopolymer PVAc (polyvinyl acetate) with PVOH Z-210 with AAEM (acetoacetoxy ethyl methacrylate) content having an acetoxy functional group. A delamination test was carried out on the final product with a modified test based on Japanese Agricultural Standard 1152 where the product was immersed in water for 360 minutes, then placed in an oven at 40oC for 18 hours. Samples using PVOH with AAEM content have an average delamination rate of 0.67-1.67% while existing products on the market have an average delamination rate of 45.83-52.08%.
Sintesis dan Karakterisasi Carbon Nanodots dengan Metode Microwave Assisted Extraction: Synthesis and Characterization of Carbon Nanodots with Microwave Assisted Extraction Mentik Hulupi; Haryadi; Nabila Sofiyani; Rizka Amalia Nuriana; Retno Indarti; Fauzi Abdilah
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 2 (2022): August 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.i2.15910

Abstract

Carbon nanodots (CNDs) is one of the carbon nanoparticles that are environmentally friendly, non-toxic, and have optical properties. The aim of this study was to synthesize CNDs from ascorbic acid as a precursor using the Microwave Assisted Extraction method. method. Best results are obtained at 4 minutes of heating and 500W of power. The synthesized CNDs solution showed a blue color under 365 nm UV light. The measurement results with UV Vis spectrophotometer showed the maximum wavelength at 341.5 nm with an energy gap of 5.57 eV. The results of the Fourier transform infrared spectroscopy (FTIR) analysis show that CNDs have the -OH (hydroxyl) functional group at a wave number of 3354.61 cm-1 and C=O functional group at a wave number of 1633.09 cm-1. Characterization results using High resolution transmission electron microscopy (HRTEM) showed that CNDs were spherical in shape with a particle size range of 2.54-9.48 nm.

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