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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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Analisis Kadar Kadmium (Cd) dalam Bawang Merah Lokal Palu (Allium cepa L. var. aggregatum) pada Berbagai Lokasi dan Umur Tanam: Analysis of Cadmium (Cd) in Palu Local Shallots (Allium cepa L. var. aggregatum) at Various Locations and Planting Ages Eka Lindawati; Khairuddin Khairuddin; Nurhaeni; Ruslan; Ahmad Ridhay; Husain Sosidi; Erwin Abdul Rahim; Syamsuddin
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): 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.2023.v9.i1.16287

Abstract

The local Palu shallot (Allium cepa L. var. aggregatum) plant is one of the leading products in the Central Sulawesi region. Shallots can experience a decrease in quality if they are contaminated with heavy metals, such as cadmium (Cd) in amounts that exceed the threshold. This study aims to determine the effect of planting age on cadmium levels in local Palu shallots cultivated in Oloboju Village and Solove Village, Biromaru District, Sigi Regency. The research variables used were the planting age which consisted of 4 levels (age 40, 50, 60, and 70 days), and the planting location which consisted of 2 levels (Solove Village and Oloboju Village). Cd levels were analyzed using an Atomic Absorption Spectrophotometer (AAS). Cadmium levels in shallot roots at two planting locations decreased with increasing planting age, from 101.34 - 107.18 mg/kg at 40 days of age to 1.68-3.78 mg/kg at 70 days of age. Shallot bulbs at two locations had lower cadmium levels than roots, namely 0.01-0.04 mg/kg. The results of the study found that planting time had a significant effect on cadmium levels in the roots of shallots, but planting age and planting location had no significant effect on cadmium levels in local Palu shallot bulbs with levels that met the SNI (Indonesian national standard) quality requirements
Produksi Konsentrat Protein dari Ampas Kelapa (Cocos nucifera L.) Menggunakan NaOH dan (NH4)2SO4 : Production of Protein Concentrate from Coconut Pulp (Cocos nucifera L.) using NaOH and (NH4)2SO4 Hasdinda Hasdinda; Pasjan Satrimafitrah; Syaiful Bahri; Abd. Rahman Razak; Dwi Juli Puspitasari; Indriani; Aini Auliana Amar
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): 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.2023.v9.i1.16290

Abstract

Coconut pulp wasted from processed coconut oil has a protein content of up to 18.20%. The potential coconut pulp protein can be processed in protein concentrate which has many benefits. This research was conducted to determine the effect of NaOH and (NH4)2SO4 concentrations in isolating protein and producing protein concentrates that have the highest yield and protein content. Isolation of coconut pulp protein was carried out using NaOH at several concentrations, namely 0, 0.2, 0.4, 0.6, 0.8, and 1 M, while the protein concentrate was prepared using the salting out method with a saturation level of the ammonium sulfate salt of 55%, 60%, and 65%. Analysis of protein content was carried out using the Kjeldahl method. The use of NaOH 0.2 M and (NH4)2SO4 with a saturation level of 60% was the chosen treatment with crude protein content and yield of 75.63% and 33.83%, respectively.
Isotermal Adsorpsi Ion Tembaga (II) Menggunakan Arang Tongkol Jagung (Zea mays L.) Teraktivasi Kalium Permanganat: Isothermal Adsorption of Copper (II) Ions Using Charcoal from Corn Cobs (Zea mays L.) Activated by Potassium Permanganate Lisma Habiba; Nov Irmawati Inda; Prismawiryanti; Husain Sosidi; Ni Ketut Sumarni; Dwi Juli Puspitasari; Moh. Mirzan; Jusman
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): 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.2023.v9.i1.16292

Abstract

Corn cobs which generally only become waste can be processed into activated carbon and used for the absorption of heavy metals, such as copper(II) ions. This study aims to determine the morphology of corn cobs charcoal after activation, determine the isothermal adsorption model of copper (II) metal ions on corncob-activated carbon, and then determine the adsorption capacity of copper (II) metal ions on corncob-activated carbon. The morphology of the corncob-activated charcoal obtained was analyzed using Scanning Electron Microscopy (SEM). Isothermal adsorption of copper (II) ions was carried out with various concentrations of copper (II) ions of 5, 10, 20, 50, and 100 ppm. The results of the analysis using SEM showed that the surface shape of the corncob-activated charcoal is regular and has pores with a pore diameter obtained in the range between 1.08-1.26 m and 1.38-1.59 m. The mechanism of adsorption of copper (II) ions by corncob-activated charcoal using KMnO4, following the Freundlich isothermal model with a value of R2 0.9993 with an adsorption capacity of 51 x 10-4 mmol/L. The utilization of activated carbon from corn cobs that are activated by potassium permanganate is very effective for adsorbing copper metal ion pollutants through an adsorption mechanism on the surface of activated carbon.
Ekstraksi Gelatin dari Tulang Ikan Tongkol (Euthynnus affinis) dengan Menggunakan Asam Belimbing Wuluh (Averrhoa bilimbi L): Gelatin Extraction from Tongkol Fish Bone (Euthynnus affinis) using Acid from Starfruit (Averrhoa bilimbi L) Musafira Musafira; Sulistiawati; Rismawati Sikanna
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): 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.2023.v9.i1.16315

Abstract

Gelatin is a type of protein resulting from the partial hydrolysis of collagen found in animals' skin, bones, and connective tissue. Gelatin is widely used in the food and pharmaceutical industries. Using Tongkol fish bones as a source of gelatin is a safe alternative for the human body and halal for consumption. Characteristics of gelatin from the bone waste of Tongkol fish extracted with starfruit acid are important to know, therefore it can be used as a substitute for cow and pork skin. The purpose of this study was to determine the characteristics of Tongkol fish bone gelatin extracted with tamarind starfruit. The extraction method was used in this research using 5 levels of starfruit acid concentration (10%, 20%, 30%, 40%, 50%) with the ratio of solvent and fish bones 1: 4 (w/v). The use of starfruit acid with a concentration of 40% produced the highest yield with the characteristics of the resulting gelatin having a brownish yellow color, yield of 1.43%, water content of 17%, ash content of 15%, degree of acidity (pH) of 6.5 and protein content of 47.98%.
Identifikasi dan Uji Aktivitas Antioksidan Senyawa Metabolit Sekunder Ekstrak Tanaman Cleome viscosa L: Identification and Antioxidants Activity Tests of Secondary Metabolite Compounds of Clome viscosa L. Plant Extracts Imran; Laily Nurliana; Muh. Natsir; Nohong; La Ode Abd Kadir; La Rudi; Ruslan; Thamrin Azis
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): 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.2023.v9.i1.16340

Abstract

Cleome viscosa L. has been used empirically by people on the island to treat diseases that have clinical symptoms such as malaria (fever, sweating, chills, and muscle aches). The purpose of this study was to determine the class of secondary metabolites and antioxidant activity. The extraction was carried out using the maceration method, while the fractionation was carried out using the separating funnel. The secondary metabolites found in the Cleome viscosa L. plant extract are alkaloids, flavonoids, steroids, terpenoids, tannins, and saponins. Antioxidant test conducted by DPPH method showed that the positive control of ascorbic acid and methanol extract obtained IC50 values of 3.86 ppm and 37.4 ppm, respectively.
Formulasi Losion Ekstrak Kopi Robusta (Coffea canephora) sebagai Penangkal Radikal Bebas: Lotion Formulation of Robusta Coffee Extract (Coffea canephora) as a Free Radical Antidote Farid Mulana; Syaubari; Syarifah Nur Afifah; Indah Tri Lestari
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 2 (2023): 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.2023.v9.i2.16333

Abstract

Hand body lotion is a cosmetic used to moisturize skin in order to reduce dehydration. The coffee extract contains bioactive compounds that can provide high antioxidant activation. The purpose of this research is to study the effect of concentration on coffee extract and the addition of olive oil on organoleptic, hedonic, pH, and dispersive properties and to determine the value of the Sun Protection Factor (SPF) in the lotion. The research method involved extracting coffee grounds, heating the oil and water phases to 65°C, and mixing the two phases till it becomes an emulsion. Then add the oil and water to the mixture. The lotion that’s already in the container is ready for testing. This research used 8 formulas with coffee extract concentrations of 2% and 4%, and variations of olive oil from 0, 1, 2, and 3%. Organoleptic and hedonic tests were tried out on 25 respondents for 2 weeks. The pH test was carried out using a universal indicator. The spreadability test was carried out using a petri dish and the SPF test using a UV-visible spectrophotometer. The results showed that 25 respondents preferred formula 4 over the rest, which was white in color, thick in texture, soft scent and the aftertaste was moisturizing. All formulas have good spreading ability and all in the pH range of 5 – 8. The SPF test results were obtained for each formulation in the range of 6.78 – 12.95 and the highest SPF value was owned by F8 of 12.95.
Laju Korosi Logam Baja Karbon Rendah di Larutan Garam pada Berbagai Konsentrasi Inhibitor Korosi dari Ekstrak Daun Pepaya: Low Carbon Steel Metal Corrosion Rate in Salt Solution at Various Concentrations of Corrosion Inhibitor from Papaya Leaf Extract Ninik Lintang Edi Wahyuni; Rony Pasonang Sihombing; Nurcahyo; Agustinus Ngatin; Yunus Tonapa Sarungu; Alfiana Adhitasari; Bambang Soeswanto; Emma Hermawati Muhari; retno indarti
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 2 (2023): 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.2023.v9.i2.16344

Abstract

Papaya leaf extract could be used as an organic corrosion inhibitor. Corrosion inhibitors were used as a method to reduce corrosion rate. The most corrosive environment was the marine environment. The purpose of this study was to determine the best concentration of papaya (Carica papaya) leaf extract inhibitor which could reduce the corrosion rate of low carbon steel in a 3.56% NaCl solution environment. The maceration process was carried out for 24 hours with 70% ethanol solvent with a solute:solvent ratio of 1:8 (w/v) at room temperature. Inhibitor extracts were analyzed qualitatively with the phytochemical method. The addition of FeCl3 was carried out on the inhibitor extract from papaya leaves. The color change occurred from blackish brown to greenish black which indicated the presence of tannin compounds in the papaya leaf extract. Corrosion testing was carried out with hot stream temperature setting at 45⁰C to 55⁰C and concentrations of inhibitor extracts at 300, 600, and 900 ppm. The test was conducted for 36 hours with a span of metal mass every 6 hours. Corrosion rate calculation is done by weight loss method. The results showed that papaya leaf extract inhibitors positive contained corrosion inhibitor and could reduce the corrosion rate in 3.56% NaCl solution. The corrosion rate without inhibitor is 1.023 mmpy. Corrosion rates with inhibitor concentrations of 300, 600, and 900 ppm were 0.755, 0.585, and 0.438 mmpy, respectively.
Pengaruh Ekstrak Biji Ketapang (Terminalia catappa L.) Terhadap Daya Hambat Pertumbuhan Bakteri Eschericia coli: Effect of Ketapang (Terminalia catappa L.) Seed Extract Against the Inhibitory Power of Eschericia coli Bacteria Growth Zelen Surya Minata Minata; Annida Elfiana Citra Ardianty; Sumari; Yudhi Utomo
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 2 (2023): 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.2023.v9.i2.16355

Abstract

Diarrheal is a disease that is widely endemic in tropical countries, especially in Indonesia. The bacterium that causes the appearance of diarrheal diseases is Eschericia coli. Plants that have the potential to be a cure for diarrhea are ketapang (Terminalia catappa L.). Ketapang seeds contain tannins, flavonoids, alkaloids, and saponins that can be used as antibacterial. This study aims to identify the effect of ketapang seed extract on the activity of E. coli bacteria. Extraction of ketapang seeds is carried out by the soxhlet extraction method with a solvent mixture of water and ethanol 96%. This research is a laboratory experiment. Bacterial growth inhibition test is carried out by the phytochemical test of ketapang seed extract with the addition of FeCl3 solution showed positive results containing tannin compound indicated by the formation of a blackish-green colored solution. Positive control was carried out with amoxicillin and negative control with 70% ethanol solution. The results of the ANOVA test analysis obtained a significance value of 0.963, interpreted that there was a difference in inhibition power in variations in the concentration of ketapang seed extract with the most effective extract concentration being 0.8%. The higher the concentration of ketapang seed extract, the greater the inhibition against the growth of E. coli bacteria, therefore it can be used as a basic ingredient for anti-diarrhea drugs.
Penentuan Kadar Albumin Ikan Gabus (Channa striata) dengan Metode Biuret setelah Dikukus dan Dipepes: Determination of Albumin Content of Snakehead Fish (Channa striata) by Biuret Method after Steamed and Wrapped Inda Hastuti N Naser; Syaiful Bahri; Pasjan Satrimafitrah; Abd. Rahman Razak; Ruslan; Ahmad Ridhay; Dwi Juli Puspitasari; Khairuddin
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 2 (2023): 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.2023.v9.i2.16391

Abstract

Snakehead fish (Channa striata) is a type of freshwater fish that contains high levels of protein albumin. The research was conducted to determine the albumin content in snakehead fish after the cooking process, both steamed and wrapped. The research was conducted using a completely randomized design with a factorial pattern, the first factor was the cooking method (steamed and wrapped) and the second was cooking time (10, 15, 20, and 20 minutes). Determination of protein albumin levels in snakehead fish after processing using the Biuret method. The steaming process for 15 minutes resulted in protein content in the snakehead fish of 0.76%, while the protein albumin that was lost was 19.28%. The wrapped method for 20 minutes has a remaining protein content of 0.59%, while the missing protein is 38.78%. The method of processing snakehead fish by steaming is better than the wrapping process.
Pemanfaatan Karbon Aktif Kulit Kacang Tanah untuk Menurunkan Kadar Ion logam Ca2+ dan Mg2+ dalam Air: Utilization Peanut Shell Activated Carbon to Reduce Levels of Ca2+ and Mg2+ in Water Wilda Yanti; Husain Sosidi; Indriani; Prismawiryanti; Dwi Juli Puspitasari; Moh. Mirzan; Erwin Abdul Rahim; Nov Irmawati Inda
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 2 (2023): 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.2023.v9.i2.16397

Abstract

Peanut shell has a high cellulose content as a carbon source which can be used as a basic ingredient for making activated charcoal. Research on peanut shells used as activated charcoal aims to determine the effect of contact time and pH on reducing levels of metal ions Ca2+ and Mg2+ in water. The research was conducted using contact time variables (30, 60, 90, 120, and 150 minutes) and pH (4, 5, 6, 7, and 8). Measurement of adsorbed metal levels was determined by using an Atomic Absorption Spectrophotometer (AAS). The research results obtained showed that variations in contact time could reduce Ca2+ levels by 77.46% -84.89% and Mg2+ by 86.88%-88.91%. Adsorbents with variations in pH can reduce Ca2+ levels by 63.48%-88.74% and Mg2+ by 90.35%-94.49%. The best conditions for the absorption of Ca2+ and Mg2+ ions were a contact time of 60 minutes and pH 4. The adsorbent was applied to reduce Ca2+ and Mg2+ levels in water with different hardness levels. The results of the analysis of water samples from two different locations had Ca2+ levels of 94.180 mg/L and 210.20 mg/L, while Mg2+ levels were 13.536 mg/L and 17.420 mg/L. The percentages of Ca2+ adsorption for the two samples were 96.19% and 77.08%, and the percentages of Mg2+ adsorption for the two samples were 21.16% and 10.63%. Carbon from peanut shells activated with sodium acetate has the potential to be used to reduce hardness in water.

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