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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 325 Documents
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Analisis Kualitatif dan Kuantitatif Metabolit Sekunder Ekstrak Biji Kelor (Moringa oleifera Lam.) dengan Metode Spektrofotometri UV-Vis: Qualitative and Quantitative Analysis of Secondary Metabolite of Moringa Seed Extract (Moringa oleifera Lam.) with UV-Vis Spectrophotometry Method Tien Wahyu Handayani; Yulistien Yusuf; Joni Tandi
KOVALEN: Jurnal Riset Kimia Vol. 6 No. 3 (2020): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2020.v6.i3.15324

Abstract

This study aims to determine the content and total levels of secondary metabolites of ethanol extract of moringa seed (Moringa oleifera Lam.). Extraction of moringa seed using the maceration method to obtain a filtrate. The filtrate obtained was concentrated using a rotary evaporator to obtain a concentrated extract. The extract was tested qualitatively for alkaloids, flavonoids, saponins, and tannins using a suitable reagent with the test parameters. The quantitative test was using UV-Visible spectrophotometry. Alkaloids using test parameters equivalent total alkaloid quinine, flavonoids use parameter test equivalent of the total flavonoids quercetin, saponin using test parameters from Quillaja total saponins and tannins quantitative bark using test parameters total tannin tannic acid equivalent. The result showed that moringa seed positive for alkaloids characterized by orange deposition, flavonoids are characterized by the formation of the yellow color orange, saponin their stable foam, and tannins are marked in black. Quantitative test results alkaloids of 916,87 µg/g, flavonoids of 0.255%, saponin of 6.367%, and tannin of 3,724.5 µg/g. Keywords: Moringa oleifera Lam., secondary metabolites, spectrophotometry
Analisis Formalin Secara Kualitatif pada Bakso dan Mie Basah di Kecamatan Sukarame, Wayhalim, dan Sukabumi: Qualitative Formaline Analysis on Meatball and Wet Noodle in Sukarame, Wayhalim, and Sukabumi Riri Fauziyya; Anjar Hermadi Saputro
KOVALEN: Jurnal Riset Kimia Vol. 6 No. 3 (2020): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2020.v6.i3.15333

Abstract

Meatballs and wet noodles are foods that are favored by the community. The high water content causes these two types of food to be vulnerable and easily damaged in storage. The addition of chemicals such as preservatives in the manufacture of food products is carried out by producers so that the products are more durable, economical, and produce maximum profit. One chemical that is often misused for food preservatives is formaldehyde. Formalin is a dangerous chemical that is carcinogenic, mutagenic, corrosive, and irritating. This study aims to determine whether there is formalin content in meatballs and wet noodles that are sold in the districts of Sukarame, Wayhalim, and Sukabumi. This research was conducted in a qualitative analysis using Schiff's reagent on 30 samples of meatballs and 30 samples of wet noodles which were sold in Sukarame, Wayhalim, and Sukabumi. The results showed that 10 samples of meatballs and 2 wet noodles showed positive results containing formaldehyde. This shows that around 33.3% of the meatball sample and 6.66% of the wet noodles sample analyzed were identified to contain formaldehyde so that they are not safe for consumption in the long term and people must be careful in selecting meatballs and wet noodles for consumption. Keywords: Qualitative analysis, formalin, meatballs, wet noodles
Pengaruh Kadar Air dan Kadar Asam Lemak Bebas Terhadap Masa Simpan Minyak Kelapa Mandar: The Influence of Water Content and Free Fatty Acid Content on Mandar Coconut Oil Shelf Life Musafira; Dzulkifli; Fardinah; Nizar
KOVALEN: Jurnal Riset Kimia Vol. 6 No. 3 (2020): Edisi Desember
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2020.v6.i3.15344

Abstract

Mandar coconut oil made in Tulu village, Majene Regency, West of Sulawesi, is very popular among Sulawesi Barat people. It is because of the unique aroma which is not owned by other Mandar oil traders. In addition, according to Mandar coconut oil trader who is also the produsen of Mandar oil said that his coconut oil could be stored for months. This research aimed to know the influence of water content and free fatty acid content on Mandar coconut oil shelf life. Gravimetric Method and Alkaline method were used to determine the water content and the free fatty acid content respectively. The oil was stored at room temperature. Water content and free acid content were measured every week, i.e week zero to week four (5 observations). Shelf life estimation was done by applying the kinetic theory. The result shows that the water content and the free fatty acid content increase as shelf life increases. Mandar coconut oil can be stored at room temperature for 1 month, 12 days. Keywords: Mandar coconut oil, water content, free fatty acid, shelf life
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.
Potential Combination of Kapok Leaf Extract (Ceiba pentandra G.) and Turmeric Extract (Curcuma domestica Va) as an Anticancer Compound Muh. Natsir; Sanang Nur Safitri; Oktovia Nurmawati; Muh. Saleh Purnama R.; 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.i1.15493

Abstract

Combination of kapok leaf extract (Ceiba pertandra G.) and turmeric extract (Curcuma domestica Va.) was carried out to determine the potential of extracts in treating cancer with BSLT and murine cells P388. Cancer is a disease that is very feared because it’s difficult to cure, and even rarely causes death. The sample was extracted with methanol, the extract was mixed so that the mixture extract from the two samples was obtained. The results showed that in the BSLT test the mixed extract had a bioactivity against shrimp larvae with an LC50 value of 142.946 ppm. While in Leukemia P388 cell testing showed that the combination of mixed extracts had a cytotoxic effect on Leukemia P388 cancer cells with inhibitory concentration values of 54.34 ppm. This shows that the kapok leaf extract (Ceiba pentandra G.) and combination of turmeric extract (Curcuma domestica Va.) has potential and can be developed as an anticancer agent because it has an IC50 value that can inhibit murine P388 cell growth and LC50 value which can kill shrimp larvae Artemia salina L.
Pengaruh Penambahan Abu Sekam Padi Terhadap Peningkatan Kualitas Minyak Mandar: The Effect of Rice Husk Ash Addition on The Increasing of Mandar Coconut Oil Quality Musafira; Dzulkifli; Hikmah; Nizar
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.i1.15494

Abstract

Mandar coconut oil is one of the coconut processed products, which has become superior product in West Sulawesi especially in Majene regency. Unfortunately, the Mandar coconut oil can’t be used more than a month because the water content and free fatty acid content of the oil have exceeded the maximum standard of SNI, so it can adversely affect on health. On the other hand, the existence of rice husk in Indonesia itself especially in West Sulawesi has not received attention and is limited to a few needs such as for ash or livestock feed, and the rest is thrown away. This research aims to determine the effect of rice husk ash addition on the increasing of Mandar coconut oil quality. Completely randomized design was used in this research with 6 rice husk ash concentration variation levels i.e. 0%, 5%, 10%, 15%, 20% and 25%. The result shows that the addition of rice husk ash with 10% to 25% can reduce the water content of the oil until the quality standard of SNI is full filled. The highest reduction of water content was reached with 25% of rice husk ash concentration with 81% of reduction percentage. While, the addition of rice husk ash with 15% concentration can reduce the free fatty acid content of Mandar coconut oil until 32%.

Page 18 of 33 | Total Record : 325

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