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INDONESIA
Jurnal Riset Kimia
Published by Universitas Andalas
ISSN : 1978628X     EISSN : 24768960     DOI : -
Core Subject : Science,
Chemistry
Arjuna Subject : -
Articles 551 Documents
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Pengolahan Limbah Pewarna Metilen Biru Menggunakan Arang Aktif dan Zeolit Aktif dengan Katalis Fe dan Oksidator Hidrogen Peroksida Maryudi Maryudi; Agus Aktawan; Shinta Amelia
Jurnal Riset Kimia Vol. 12 No. 2 (2021): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i2.414

Abstract

The textile industry including batik has provided broad benefits to society from an economic standpoint. However, there is negative impact from wastewater generated in the production process, which is containing dyes. Various types of dyes are used in the coloring process, and methylene blue is one of most used dye. Various ways have been done to treat wastewater containing methylene blue. Methylene blue processing techniques by adsorption have been carried out with various types of adsorbents. Research on the comparison of the ability of commercial activated charcoal and commercial activated zeolite to adsorb methylene blue was carried out with the addition of an Fe catalyst and a hydrogen peroxide oxidizer. The results showed that the addition of Fe catalyst would increase the degradation of methylene blue in the waste either with activated charcoal or activated zeolite. The combination of using Fe catalyst and hydrogen peroxide oxidizer further increases the removal of methylene blue in both types of adsorbents, activated charcoal and activated zeolite. Activated zeolite has the better ability to adsorb methylene blue than activated charcoal under various conditions.
Voltametri Pelucutan Anodik Menggunakan Elektroda Pasta Karbon Termodifikasi Bentonit untuk Penentuan Kadar Ion Cd(II) dalam Sayur Sawi Putih Irdhawati Irdhawati; Ni Kadak Nevi Titasia; Emmy Sahara
Jurnal Riset Kimia Vol. 12 No. 2 (2021): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v12i2.417

Abstract

In this study, the measurement of Cd(II) ion by anodic stripping voltammetry technique was conducted using bentonite modified carbon paste as working electrode (CPE-B). The performance of CPE-B was compared with carbon paste electrode without bentonite (CPE) and applied for determination of Cd(II) concentration in chicory. Optimized parameters were composition of bentonite in carbon paste electrode, deposition time, deposition potential, and scan rate. Validation of measurements was observed including determination of linear concentration range, detection and quantization limits, repeatability of measurement, and percentage of recovery. The optimum composition of bentonite in CPE-B was found at 50%. Furthermore, in the optimization of measurements condition was found the optimum deposition times were 90 and 60 s, deposition potentials were -0.63 and -0.53 V, and scan rates were 15 and 20 mV/s, for CPE and CPE-B. The linear range concentration for CPE observed at 25-2000 µg/L and CPE-B was 5-50 µg/L. Limit of detection and quantization using CPE-B were 0.337 µg/L and 0.349 µg/L, lower than CPE i.e., 0.470 µg/L and 0.471 µg/L, respectively. Repeatability measurement of Cd(II) had Horwitz Ratio value less than two, and percentage of recovery was 96.73 8.33%. The level of Cd(II) ion in chicory was found at 6.98 0.40 mg/kg.
Penentuan Kandungan Antioksidan Total pada Infusa Selada Hijau (Lactuca sativa L.) Hidroponik dan Konvensional secara Spektrofotometri dengan Modified Phenantroline Method (MPM) Yefrida Yefrida; Refilda Refilda; Nofi Hamidah; Widuri Rosman
Jurnal Riset Kimia Vol. 13 No. 1 (2022): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i1.492

Abstract

Green lettuce is a vegetable that is widely consumed in Indonesia. These vegetables come from conventional and hydroponic farming. This study aims to compare the antioxidant content of these two types of vegetables. This vegetable is extracted by the infundation method. The extract obtained was determined for its antioxidant content by the MPM method. This method was validated by using parameter LoD, LoQ, linearity, precision and accuracy. The results showed that this method was valid for determining the total antioxidant content in conventional and hydroponic green lettuce samples. The total antioxidant content in conventional and hydroponic green lettuce samples was 2.68 ± 0.65 mg aa/g FW and 1.67 ± 0.40 mg AA/g FW, respectively. T test stated that the antioxidant content of the two samples was significantly different.
The Effect Of Sulphur (S) Doping and K+ Adsorption To The Electronic Properties Of Graphene: A Study By DFTB Method Yuniawan Hidayat; Fitria Rahmawati; Eddy Heraldy; Khoirina Nugrahaningtyas; IF Nurcahyo
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.485

Abstract

A study on the effect of S doping and K+ adsorption to the electronic properties of graphene has been conducted by DFTB (Density Functional Tight Binding) calculation. The supercell of 40 x 40 x 1 configured from the 4x4x1 unit cell of graphene was optimized. The calculation shows that the Fermi level of graphene shifted from -4.67 eV into -3.57 eV after S doping. In addition, the S presence caused the formation of gap within the Dirac K of valence band and conduction band. Meanwhile, K+ charge distribution was dominantly occurred within the S-graphene than the graphene.
Teknik Edible Coating dengan menggunakan Campuran Gel Lidah Buaya dan Ekstrak Daun Psidium guajava L. untuk Mempertahankan Sifat Fisikokimia Buah Jambu Biji Refilda Refilda; Riga Habib Ngestu; Emil Salim; Yefrida
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.501

Abstract

The synthetic chemicals is a common substance used to extend the shelf life of postharvest fruit. But it can have health impact. The use of edible coatings from natural ingredients has begun to be developed. Modification of aloe vera gel by guava leaf extract as the edible coating to increase guava fruit shelf life has not been reported yet. Guava fruit coated by several compositions of aloe vera gel and guava leaf extract have been carried out. Observations on physichochemical in fruit on the days 0, 3, 6, 9, 12 and 15 were evaluated. The best quality found on guava fruit treated with the compotition of aloe vera gel:ethanol guava leaf extract: CMC:glycerol (90: 5:0.25: 0.5) on the day 15. It had a weight loss of 9.88%, a spoilage of 3.33%, the decrease of water content 11.61%, titratable acidity 0.5%, total antioxidant 1.08 mg AA/g FW, total phenolic 0.51 mg GAE/g FW, and increase of total dissolved solids 3.01 oBrix. This result was significantly better than the uncoated fruit. It can be concluded that guava leaf extract can be used to maintain the physicochemical properties during storage.
Evaluation of Lipid Profile and Liver Function After Administration of Scenedesmus dimorphus in Obese Mice Armaini Armaini; Siti Hajir; Yetria Rilda
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.503

Abstract

Obesity is a major public health problem in developing countries and is a significant risk factor for metabolic disorders. Microalgae Scenedesmus dimorphus (S. dimorphus) contains bioactive compounds such as pigment function as antioxidants, and omega-3 and omega-6 PUFAs have potential as nutraceuticals. The study aimed to evaluate the lipid profile and liver function after the administration of S. dimorphus in obese mice. The research design uses mice which are divided into 6 groups; Group 1 (G1) normal control, G2 control Obesity, G3 treatment with Orlistat, G4 treatment S. dimorphus (0.25mg/g BW), G5 treatment S. dimorphus (0.5 mg/g BW) and G6 treatment S. dimorphus (0.75 mg/g BW) each group consisted of 5 mice and 21 days of observation time. The parameters observed were lipid profile and liver function of mice. Based on the results of the study, the effective dose for treating obesity is a dose of S. dimorphus 0.75 mg/g (BW) can reduce cholesterol, triglycerides, and LDL levels, respectively 67.7 mg/dl, 49.2 mg/dl, 10 , 2 mg/dl, and increased HDL, 68.32 mg/dl compared to control of obesity (G2), respectively 108.7 mg/dl, 139.1 mg/dl, 20.6 mg/dl and HDL 60, 28 mg/dl, this dose is also effective for improving the function of blood pressure by reducing AST and ALT 15.6 U/L and 18.8 U/L, respectively, compared to the obesity group (G2), which is 26.6 U/L, and 29,7 U/L. Based on the results of the study it can be concluded that S. dimorphus is useful for anti-obesity for mice (Mus musculus).
Pengaruh Lama Penyimpanan dan Pengenceran Lindi Hitam Terhadap Karakteristik Lignin Kraft Acacia mangium Faizatul Falah; Rikna Naila Salsabila; Wita Pradiani; Azizatul Karimah; Muhammad Adly Rahandi Lubis; Arief Heru Prianto; Nissa Nurfajrin Solihat; Fahriya Puspita Sari; Rita Rusman; Irawan Kusuma Wijaya; Widya Fatriasari
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.506

Abstract

This study aimed to investigate the effects of storage time and dilution of black liquor (BL) from Acacia mangium kraft pulping on the characteristics of isolated Lignin. Lignin isolation was carried out by 1 and 2 steps of isolation using HCL 1M to precipitate Lignin, diluted before isolation. Isolated Lignin was analyzed for its acid-soluble Lignin (ASL), insoluble acid lignin (AIL), functional groups by FTIR, solubility in dioxane and NaOH and thermal properties. The effect of BL storage time was also evaluated on the characteristics of the Lignin produced. The results suggest that the longer BL is stored, the higher the lignin yield. When compared to the isolation approach without dilution, the dilution process produced a higher yield and ash content up to 84% and 21%, respectively. Without dilution, the AIL isolated was lower than the dilution during BL storage. The longer the storage duration, the higher the lignin purity. Compared to two-step lignin isolation, dilution treatment in single-step isolation improves yield and purity. The thermal stability of lignin isolation without dilution (184 ⁰C and 167 ⁰C for 1 and 2 steps, respectively) was higher than that of isolated Lignin with dilution (154.8 ⁰C and 160.9 ⁰C for 1 and 2 steps, respectively), according to thermal study. Both lignin isolates with and without dilution have comparable functional groups, as shown by FTIR spectra. Due to the high yield and purity of isolated Lignin, BL dilution could be a viable alternative in lignin isolation from BL. Moreover, the properties of isolated Lignin are also influenced by BL storage.
Ekstraksi Tanin dari Limbah Kulit Biji Asam dan Penggunaannya Sebagai Biomordan pada Pewarnaan Tenun Timor Secara Alami Risna Erni Yati Adu; Marselina Theresia Djue Tea; Yunita Bouk
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.509

Abstract

Tannins from tamarind seed husk were extracted and applied as a biomordant for natural dyeing process of Timor woven fabrics. Tannins were extracted using hot distilled water, qualitatively and quantitatively analyzed and applied as a color binder to the woven fabrics. The color characteristics of woven fabrics with tannins were compared to the woven fabrics that mordanted with Al2(SO4)3 and FeSO4 at the concentration of 15%. Tamarind seed husk tannins are in the form of a brownish red powder. Qualitative and quantitative tests showed that tamarind seed coat contained condensed tannins with a total concentration of 70.08 ± 0.14%. Tannins identification by FT-IR spectroscopy showed a strong band absorption at 3369 cm-1 for O-H group and a weak absorption at 1721 cm-1 due to the C=O stretch. A strong absorption at 1611-1608 cm-1 was observed for C=C group in the aromatic ring and was strengthened with a strong absorption at 1520 cm-1, C-O-C group which is specific for condensed tannins was observed at 1285 cm-1. Application of 15% tannin as a biomordant without natural dye on Timor woven fabric produced a brownish red color, while the use of 15% tannin and turmeric dye showed a brownish yellow color. Tannin exhibited a better color fastness than metalic mordants in natural dyeing of Timor woven fabrics.
Aktivitas Anti Hiperurisemia Ekstrak Akar Kaik-kaik (Uncaria cordata. L. Merr) pada Mencit (Mus muscullus) yang Diinduksi Kalium Oksonat Nurhamidah Nurhamidah; Rima Fadillah; Elvinawati Elvinawati; Dewi Handayani
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.517

Abstract

Consuming food containing high level of purin leads to increase uric acid in the blood which, in turn, cause hyperuricemia or high uric acid level. The use of improper allopurinol for hyperuricemia medication that doesn’t follow medical doctor’s prescription can give harmful side effect. It is therefore required to use an alternative safe medication. Uncaria cordata (Lour.) Merr.) is a plant often used for medication of high levels of blood uric acid by communities in Pasar Ngalam village, Bengkulu Province. This research aims to evaluate the potency of extracted compounds from Uncaria cordata (Lour.) Merr.) in reducing uric acid of Mus musculus suffering from hyperuricemia. This research is a laboratory experiment using completed random design. As many as 25 Mus musculus were divided into 5 groups of treatment: PN = normal treatment, PA = treated with allopurinol, P1 – P3 = treated with extracted compound of Uncaria cordata (Lour.) Merr.) with a dose of 5.3 mg/30gBW (P1); 10.6 mg/30gBW (P2); and 21.2 mg/30gBW (P3). In order for Mus musculus to suffer from high uric acid level, potassium oxonate-induced hyperuricemia was injected. The result showed that extracted compounds of Uncaria cordata (Lour.) Merr.) using ethanol exhibited antihyperuricemia proven by decline of uric acid level of Mus musculus from hyperuricemia on each given dose. Decreasing uric acid level for each given dose of ethanol extract (5.3 mg/30gBW, 10.6mg/30gBW and 21.2mg/30gBW) was not significant different (0.541; with a ³0.05).
Pemanfaatan Ekstrak Biji Feun Kase (Thevetia peruviana) sebagai Inhibitor Korosi Logam Seng dalam Media HCl Matius Stefanus Batu; Maria Magdalena Kolo; Adolvina Kono
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.520

Abstract

Feun Kase seed extract can be used as a corrosion inhibitor on zinc metal in HCl solution. This study aims to determine the secondary metabolites contained in Feun Kase seed extract, inhibition efficiency and corrosion rate, and surface morphology of zinc metal in the inhibition process using Feun Kase seed extract in HCl media. Feun Kase seed extract was obtained by maceration extraction using methanol. In the corrosion inhibition test, the concentration and temperature variations were carried out to determine the effect on the inhibition efficiency and the corrosion rate per year. The results showed that the methanol extract of Feun Kase seeds contained secondary metabolites of alkaloids, flavonoids and saponins. The optimum inhibition efficiency was obtained at an inhibitor concentration of 30 ppm of 82.70% with a corrosion rate of 5.80 mm/year and at a temperature of 35ºC of 75.84% with a corrosion rate of 7.28 mm/year in the test of increasing the temperature of the corrosion medium. The morphological analysis of the zinc plate using the SEM instrument showed that the zinc plate without surface treatment (not immersed in HCl media) was still smooth. This is indicated by the surface of the zinc plate which is still clearly visible because it has not been affected by the corrosion medium. The zinc plate when immersed in HCl media, is damaged which is indicated by the presence of pores or holes. Zinc plate when added with Feun Kase seed extract in HCl media, the zinc surface was damaged but the damage was not as prominent as in HCl media without using an inhibitor.

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