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Jaya Hardi
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INDONESIA
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 12 Documents
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Search results for , issue "Vol. 7 No. 1 (2021): Edisi April" : 12 Documents clear
Ekstraksi Glukomanan dari Umbi Gembili (Dioscorea esculenta L.): Extraction of Glucomannan from Gembili Bulbs (Dioscorea esculenta L.) Pratiwi Listyana Sareu; Nurhaeni; Ahmad Ridhay; Moh. Mirzan; Syamsuddin
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.12008

Abstract

Gembili bulbs (Dioscorea esculenta L.) have a fairly high carbohydrate content, so they can potentially be a new source of glucomannan compounds. This study aims to determine the yield and glucomannan characteristics of Gembili bulbs at different extraction times and temperatures. Glucomannan was obtained by extraction with water at temperatures of 45, 60, 75, 90, and 105oC for 45, 60, 75, 90, and 105 minutes, and precipitated with isopropyl alcohol. The results showed that the highest yield was obtained at the extraction time of 90 minutes and a temperature of 105oC of 53.09%. The glucomannan of Gembili bulb has a molecular weight of 1,865 x 104 g/mol with ash and water content values of 0.866% and 10.45%, respectively. The results of identification of functional groups with an FTIR spectrophotometer showed that there was a functional group stretching vibration of glucomannan compounds, including the –OH group at a wavenumber of 3431 cm-1 and -C-O-C (glycosidic bond) at a wavenumber of 1020.34 cm-1 and bending vibration of -CH functional groups on wavenumber of 850.61 cm-1.
Siklisasi Sitronelal Menggunakan Polimer Penyangga Katalis H2SO4 Berbahan Dasar Eugenol: Citronellal Cyclization Using Polymer Based-Eugenol Supported H2SO4 Catalyst Moh. Rifki Saputra; Erwin Abdul Rahim; Husain Sosidi; Ni Ketut Sumarni
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.13660

Abstract

Research on citronellal cyclization using a polymer based on eugenol supported H2SO4 catalyst has been carried out. The study aim was to determine the ratio of the addition of polymer based-eugenol supported H2SO4 catalyst used to produce the highest isopulegol. Citronellal cyclization was carried out using variations of catalyst concentration (1, 2, 3, 4, and 5%) and reaction time (30, 60, and 90 minutes). The results have obtained a yield of 50.67% found in the catalyst concentration of 1% and 90 minutes reflux time. From the results of GC-MS analysis, 29 compounds were read and among them isopulegol which was read at retention time 19.703 at peak 9 and peak area 4.76%. And the isopulegol results obtained are 11.34%.
Adsorpsi Logam Merkuri (Hg) dari Limbah Tanah Tercemar Menggunakan Tanaman Sawi (Brassica juncea L) pada Berbagai Waktu Tanam: Adsorption of Mercury (Hg) from Contaminated Soil Waste Using Sawi Plants (Brassica juncea L) in Various Planting Times Khairuddin; Wiranto Wengkau; Dwi Juli Puspitasari; Husain Sosidi; Nov Irmawati Inda
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.13666

Abstract

Mercury (Hg) as a gold extractor can cause environmental pollution, therefore, hyperaccumulator plants are needed, such as mustard greens (Brassica juncea L). Research on the effect of planting time of mustard greens on the adsorption of mercury (Hg) metal ion on contaminated soil waste has been carried out. The purpose of this research was to determine the concentration and adsorption mechanism of Hg metal ion from contaminated soil at roots and canopy of mustard plants at various planting times. Amount of Hg metal ion adsorbed on the roots and canopy of mustard greens at 2, 4, and 6 weeks of planting times were analyzed using Atomic Absorption Spectrophotometry (AAS). The results showed that the average levels of Hg metal ion adsorption at various planting time of 2, 4, and 6 weeks at roots were 156.611 μg/g, 810.256 μg/g, and 888.711 μg/g, respectively, and at the canopy were 69.486 μg/g, 134.580 μg/g, and 60.416 μg/g, respectively. The planting time of 6 weeks resulted in the highest adsorption ability of Hg at the roots. The results of the bioconcentration factor (BCF) test showed that the adsorption of Hg in the roots and canopy of the mustard plant took place using a phytoextraction mechanism (BCF < 1).
Pengaruh Konsentrasi Asap Cair Terhadap Mutu, Total Bakteri, dan Waktu Simpan Ikan Cakalang (Katsuwonus pelamis) Asap: Effect of Liquid Smoke Concentration on Quality, Total Bacteria, and Shelf Life of Smoked Skipjack Fish (Katsuwonus pelamis) Angria Deswika Malambu; Syaiful Bahri; Hardi Ys.; Prismawiryanti; Abd. Rahman Razak
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.14238

Abstract

Liquid smoke contains acid, carbonyl, and phenolic compounds, so it is very appropriate to be used as a preservative. Traditional smoking can be replaced with liquid smoke because it is safer and more practical. The study of the use of coconut shell liquid smoke has been used in skipjack fish to determine the effect of liquid smoke concentration and storage time on dissolved protein content and total bacteria in smoked fish. The quality of smoked fish was determined by two treatments, namely the variation in the concentration of liquid smoke (2, 3, 4, and 5%) and storage time (2, 4, 6, 8, and 10 days). The results showed that the best concentration of liquid smoke to produce smoked skipjack fish is 3% with a water content of 62.41% and dissolved protein content of 17.58%. The maximum storage time of smoked skipjack tuna is 6 days with a total plate count (TPC) value or total bacteria 1.8 x 105.
Identifikasi dan Purifikasi Vitelogenin Arwana Asia: Banjar, Pinoh (Scleropages macrocephalus), Papua (Scleropages jardinii) dan Super Red (Scleropages legendrei): Identification and Purification of Asian Arowana Vitellogenin: Banjar, Pinoh (Scleropages macrocephalus), Papua (Scleropages jardinii) and Super Red (Scleropages legendrei) Ahmad Musa; Remi Dugue; Rina Hirnawati; Bastiar Nur; Rendy Ginanjar; Sawung Cindelaras; Slamet Sugito
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.15314

Abstract

Arowana fish (Scleropages sp.) are monomorphic species, those animals that physically could not be distinguished between male and female. The research was aimed to identify and purify Vitellogenin of four variants of Asian Arowana: Banjar, Papua, Pinoh, and Super red. 12 fishes, 3 from each variant were given estradiol stimulation through toad for vitellogenin production purpose. The SDS-PAGE results expressed that there were two types of Asian Arowana vitellogenin characters, single Vtg for Arowana Banjar, Pinoh (Scleropages macrocephalus) and Super Red (Scleropages legendrei) with a molecular weight of 180 kDa and double Vtg in Papuan Arowana (Scleropages jardinii) with molecular weight 180 and 110 kDa. Pure vitellogenin has been collected from 3 varieties, Banjar, Papua, and Super red with a concentration range between 0.1 - 0.67 mg / mL. The actual concentration is believed to be greater than the measured concentration.
Penentuan Aktivitas Antioksidan dan Kandungan Flavonoid Total Ekstrak Daun Papasan (Coccinia grandis L.) Berdasarkan Perbedaan Pelarut Polar : Determination of Antioxidant Activity and Total Flavonoid Contents Extract of Papasan Leaves (Coccinia grandis L.) Based on The Differences Polar Solvents Meliani Sari; Rani Nareza Ulfa; Mauritz Pandapotan Marpaung; Purnama
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.15437

Abstract

Papasan leaves have several properties, including antihyperglycemic, diabetes, antipyretic and antioxidant. Minor metabolite compounds that have the potential as antioxidants from this plant are flavonoids, alkaloids, saponins, and tannins. This study's purpose to determine the antioxidant activity and the flavonoid total contents of Papasan (Coccinia grandis L.) leaf extract based on the differences in polar solvents. The polar solvents used were ethanol, methanol, and water. Extraction used by maceration and dekokta. The antioxidant activity and the flavonoid total contents were established by UV-Vis spectrophotometry according to the decrease in absorbance at a maximum wavelength of 515 nm by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. Determination of antioxidant activity and the flavonoid total contents were excluded on quercetin comparisons. The values of IC50 and the flavonoid total contents in the ethanol extract respectively were 287.92 ppm and 49.825 mg QE/g while the IC50 values and total flavonoid levels in the extract of methanol were 73.29 ppm and 50.415 mg QE/g. In the extract of the water, the value of IC50 was 39.80 ppm and the total flavonoid contents were 50.415 mg QE/g. The conclusions of these studies were that the most antioxidant activity was found in water extract, while water and methanol extract had the same and highest levels of total flavonoids.
Aktivitas Antischistosomiasis Sediaan Nanopartikel Ekstrak Biji Pinang pada Tikus Putih Jantan Terinfeksi Schistosoma japonicum: The Antischistosomiasis Activity Test on Nanoparticles Ethanolic Extract of Betel Nut to Male Rats Infected with Schistosoma japonicum Marzela Dewi; David Pakaya; Joni Tandi
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.15438

Abstract

Schistosomiasis is a disease caused by Schistosoma japonicum worms and Oncomelania hupensis lindoensis as the intermediate snails. Praziquantel is a drug used to reduce the prevalence of schistosomiasis. However, its use has several side effects such as headaches, dizziness, nausea, vomiting as well as abdominal, joint, and muscle pain. The development of alternative drugs is a solution to reduce side effects. Betel (A. catechu) seeds are known to the public to have an anthelmintic effect because they contain alkaloids, tannins, flavan, phenolic compounds, as well as arecoline. To increase the bioavailability and efficacy of the extract, the seeds were prepared in the formulation of nanoparticles. This study aims to determine the antischistosomiasis activity of the ethanol extract nanoparticles of betel nut as an antischistosomiasis. The rats were divided into 9 treatment groups consisting of normal, negative and positive control groups, extract treatment and treatment of nanoparticle preparations with dose variations of 30, 60, and 120 mg/kgBW. The parameter observed was the number of S. japonicum eggs in rat feces before and after treatment. Data obtained from the mean number of S. japonicum eggs was tested for normality with Saphiro-Wilk test, and showed that the data were not normally distributed. Furthermore, nonparametric statistical analysis was carried out with Kruskal-Wallis which showed there was no significant difference in the mean number of S. japonicum eggs in all treatment groups. The results showed that the ethanol extract nanoparticles of A. catechu had antischistosomiasis activity.
Kapasitas Bioadsorpsi Bakteri Simbiosis Spons Laut Terhadap Kontaminan Logam Berat: Bio-adsorption Capacity of Marine Sponge Symbiosis Bacteria on Heavy Metal Contaminants Anggi Angela; Ismail Marzuki
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.15439

Abstract

Heavy metal pollution in the marine environment is quite high. Arsenic and Mercury are two types of dangerous heavy metals because they are toxic and are often found as components of pollution. The research objective was to determine the bio-absorption capacity and efficiency of sponge symbiotic bacteria against arsenic and mercury contaminants. The bio-absorbent material was used by two bacterial isolates, namely Bacillus licheniformis strain ATCC 9789 (Bl.6), the sponge symbiont Auletta Sp and Acinetobacter calcoaceticus strain PHCDB14 (Ac.8), the sponge symbiont Callyspongia aerizusa. The isolates were prepared through culture, then incubated 2 x 24 hours, suspension Bl.6 and Ac.8 were made, then adapted for 24 hours. Interaction with As3 + and Hg2 + contaminants with a concentration of 100 ppm in vials with time variations 0, 4, 8, 12, 16 days. The resulting interactions are extracted, concentrated, and acidified. The bio-absorption capacity and efficiency were determined based on absorption data using Atomic Absorption Spectrometry (AAS). The average efficiency of the bio-absorption of isolate Bl.6 against As3+ = 99.95%, Hg2+ = 88.49%, while isolate Ac.8 against As3+ = 99.95% and Hg2+ = 85.73%. Based on efficiency data, capacity and bio-absorption power relative to Bl.6 = Ac.8 against As3+ and Bl.6 ≥ Ac.8 contaminants to Hg2+. Isolates Bl.6 and Ac.8 adsorbed more strongly against As3+ contaminants than Hg2+.
Kajian Pustaka Karakterisasi Perekat Polivinil Asetat Berbasis Air dengan Variabel Surfaktan: Water Base Polyvinyl Acetate Characterization with Surfactant Variable – a Review Rony Pasonang Sihombing; Dieni Nurul Fathiyyah; Nanda Liant Kumara; Agustinus Ngatin
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.15448

Abstract

Polyvinyl acetate (PVAc) is an applicative polymer used as an adhesive material for one to another. These polymers can be synthesized through an emulsion polymerization process. In the industrial world, the process of making adhesive still involves environmentally unfriendly organic compounds containing xylene, benzene, and toluene. Therefore, water-based adhesive was introduced as an alternative to the PVAc synthesis solution. The aim of this literature review is to identify the type of surfactants used and analyze the PVAc characterization. This literature study focuses on the characterization of water-based PVAc with non-ionic nonylphenol (NP) surfactants including: NP-06, NP-10, NP 10 + 30, NP-30 and NP-40. Another surfactant used in this literature study is anionic surfactant Sodium Lauryl Sulfate (SLS) in units of Critical Micelle Concentration (CMC) including 1 CMC, 3 CMC, 5 CMC, 10 CMC, and 15 CMC. The result is a similarity in phenomena between the two types of surfactants. There is an increase in viscosity and a decrease in the value of the particle size as the surfactant increasing concentration used. However, in terms of the particle size, there is an optimal value where the specific NP surfactant concentration produces specific particle size with grit and at the specific SLS surfactant concentration produces relatively similar particle size.
Penyarian Konstituen Organik Daging Buah Gaharu (Aquilaria malaccensis Lamk.) dengan Metode Maserasi Berbantu Microwave dan Uji Aktivitas Sebagai Antioksidan: Organic Constituent Extraction of Gaharu Fruit (Aquilaria malaccensis Lamk.) Using Microwave Assisted Maseration Method and Activity Test as Antioxidant Imran; Nurlian; L.A. Kadir; La Agusu; Ruslan
KOVALEN: Jurnal Riset Kimia Vol. 7 No. 1 (2021): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2021.v7.i1.15478

Abstract

This study was conducted to determine the organic constituents and to test the antioxidant activity and toxicity of gaharu fruit pulp extract (Aquilaria malaccensis Lamk.). Gaharu fruit pulp extract was obtained through Microwave Assisted Extraction (MAE) method and then extracted with a solvent with different polarity, namely ethyl acetate and n-hexane. The obtained yield of ethyl acetate extract of the gaharu fruit pulp was 40.827% w/v, whereas 0% w/v in n-hexane extract, therefore, no further test for n-hexane extract, so that the n-hexane extract was not tested for the next stage. The results of the organic constituents of the ethyl acetate extract of gaharu fruit pulp showed flavonoids, saponins, glycosides, phenols and tannins. Antioxidant activity testing was carried out using the DPPH method with vitamin C as a positive control. The results of the antioxidant activity test showed that IC50 of ethyl acetate extract of gaharu fruit pulp and vitamin C were 143.789ppm and 13.797ppm, respectively. Extracts from microwave-assisted maceration that were partitioned with ethyl acetate solvent were categorized into moderate antioxidants because the IC50 value was between 101-150ppm, while vitamin C was categorized as a strong antioxidant because the IC50 value was between 0-100ppm. Toxicity testing was also carried out on ethyl acetate extract of gaharu fruit pulp using the BSLT method. The results of the toxicity test of the ethyl acetate extract of gaharu fruit pulp showed activity with an LC50 value of 11.282ppm. Based on this research, the ethyl acetate extract of gaharu fruit pulp is considered to have an anticancer potential.

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