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INDONESIA
Jurnal Kimia Riset
Published by Universitas Airlangga
ISSN : -     EISSN : -     DOI : -
Core Subject : Science,
Chemistry
Arjuna Subject : -
Articles 190 Documents
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VALIDATION OF HEADSPACE SOLID-PHASE MICROEXTRACTION WITH GAS CHROMATOGRAPHY-FLAME IONISATION DETECTOR METHOD FOR ALCOHOL ANALYSIS ON GASTRIC FLUID Thaiyibah, Nazaratun; Yuwono, Mochammad; Yudianto, Ahmad
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.44502

Abstract

Identifying the concentration of alcohol compounds in postmortem analysis of biological fluids can help the investigation, just as postmortem analysis of gastric juices can reveal the concentrations of alcohol consumed. However, an efficient and effective combination of extraction and measurement methods is required when looking at complex postmortem samples. Therefore, a headspace-solid phase microextraction (HS-SPME) method was developed using gas chromatography with a flame ionization detector (GC-FID) to identify postmortem alcohol concentrations. This present study optimizes and validates an effective and efficient method for postmortem alcohol extraction and quantification in gastric fluid. The optimal conditions for HS-SPME extraction using 65μm Polydimethy lsiloxane Divinyl benzene (PDMS/DVB) fiber for analyte isolation were 15 minutes. at 60°C and an exposure time of 1 minute. The validation investigation shows that the suggested approach satisfies the criteria for linearity, precision, accuracy, LOD, and LOQ for postmortem measurement of alcohol in gastric fluid.
DETERMINATION OF VITAMIN C CONTENT IN BELL PEPPER (Capsicum annuum L.) WITH DIFFERENT PROTIC POLAR SOLVENT BY UV-VIS SPECTROSCOPY Afnani, Fawait; Yanti, Jamilah Hamidi; Pratiwi, Wiwit Sri Werdi
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.44865

Abstract

Bell pepper can be an antioxidant and has many health benefits because of the high content of vitamin C. Vitamin C contents in yellow and orange bell peppers were extracted using different protic polar solvents and analyzed using the UV-Vis Spectrophotometry method. In this research, the bell peppers were extracted using the maceration technique for two days in 90% concentration of solvents (methanol and ethanol, respectively). Subsequently, the maximum wavelength was determined, and then 100 ppm ascorbic acid was used as a standard solution to analyze vitamin C content. Linearity based on a calibration curve is used to obtain the correlation coefficient of concentration between the standard solution and vitamin C levels in the sample. The result of UV-Vis spectroscopy analysis of this sample shows 373.5 nm of λmax. The linearity is shown in the equation y = 0.0006 x + 0.019. The vitamin C content in all samples had significant differences based on randomized complete block design (RCBD) test result with α = 0.05. The vitamin C level in the yellow pepper sample with an ethanol solvent (340 mg/100 g) was higher than that of the orange pepper sample with ethanol (251 mg/100 g). Meanwhile, the vitamin C content in the sample of yellow peppers with methanol solvent (562.5 mg/100 g) was smaller than that of orange peppers with methanol solvent (757.5 mg/100 g). These contents indicated a different result in the level sources of vitamin C, even if the maceration process used a solvent with a higher dielectric constant.
DIFFERENT ROUTES FOR THE SYNTHESIS OF BENZALDEHYDE-BASED DIHYDROPYIMIDINONES VIA BIGINELLI REACTION Ilfahmi, Yan Alamanda; Fadlan, Arif
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.45209

Abstract

Multicomponent reactions involving three or more reactants are commonly used to prepare dihydropyrimidinone with various bioactivities. This study reports the different routes for the synthesis of benzaldehyde-based dihydropyrimidinone via the Biginelli reaction and investigates the yield of the obtained products. The synthesis was performed via routes A, B, C, D, and E based on the formation of iminium, enamine, and Knoevenagel intermediates between urea, benzaldehyde, and ethyl acetoacetate. Route A, through a one-pot reaction via iminium, produced dihydropyrimidinone with a yield of 58%. The product from route B via iminium was obtained in 62% yield. Route C and D occurred via enamine at room temperature, and reflux gave the product 31% and 40% yield, respectively. Route E involving Knoevenagel intermediate provided the product in a 38% yield. 1H NMR, FTIR, and MS spectroscopic techniques were used for structure elucidation.
WATER ROLE ON DIELS-ALDER REACTION OFPRENYLATED FLAVONOIDFORMATIONIN Boesenbergia pandurata: MECHANISM STUDY Rusdipoetra, Rahmanto Aryabraga; Kautsar Ul Haq
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.45215

Abstract

Panduratin A is a prenylated flavonoid derivative from Boesenbergia pandurata with many potential biological activities. The biogenesis of this compound and its derivatives is believed to involve a Diels-Alder reaction between monoterpenoid and chalcone derivatives. This study provides insight into modeling biogenesis through the Diels-Alderreaction for Panduratin A and derivatives biosynthesis. We are using M06-2X/6-31G(d)//PM6 level of theory to explore the potential energy surfaces, asynchronicity degree, and global electron density transfer. Explicit water was applied to mimic physiological conditions. Contrary to the fact that water accelerates this reaction through hydrogen bonding catalysis, we found that water could slow this reaction. These results suggest that this reaction proceeds very slowly under physiological conditions, and enzymes catalyze this reaction.
EFFECT OF MAGNETITE AND CHITOSAN-MAGNETITE ADDITION ON BACTERIAL LEVELS AND NH3-N (FREE-LIVING N2-FIXING BACTERIA CULTURE) Umar, Ali; Saprudin, Deden; Hazra, Fahrizal
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.47647

Abstract

Free-living N2-fixing bacteria are essential in the soil because they provide a source of nitrogen in the form of ammonium needed by plants to be used in building protein blocks. The fixation of free N2 needs to be increased by adding nanomaterials such as magnetite (Fe3O4), which has an active group and can be a source of nitrogenase enzyme cofactor. In this study, increased N2 fixation used N2-fixing bacteria in Burks medium. This increase was determined by measuring NH3 levels using the Phenate method formed after Burks medium was treated with Fe3O4 and chitosan-magnetite (CS-Fe3O4). The study found that the number of bacteria can be well decreased. This research showed that using Fe3O4 and CS-Fe3O4 increased NH3-N levels in cultures of free-living nitrogen-fixing bacteria by 15.40% and 75.54%. For future development, it can be in the form of optimization, the effect of adding the same material to plant secondary metabolites, and the mechanism of bacteria in using the material.
THE EFFECT OF SURFACTANT ON PRE-MORDANTING AND pH OF DYEING PROCESS WITH NATURAL DYES Atikah, Wulan Safrihatini; Muslim, Ikhwanul; Pratama, Sandi Mu'min
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.49114

Abstract

The dyeing process with natural dyes has disadvantages, including poor color fastness. A mordanting process is required to overcome these disadvantages. Conventional mordanting processes often use metal salts. This research will substitute the mordanting process using surfactants as mordant substances. The pH of the process influences the application of dyeing with natural dyes. This study aims to determine the effect of the pre-mordant process using surfactants and the pH of the dyeing process on the color characteristics of cotton and silk fabrics dyed with Cocos nucifera L dye extract. The surfactants used were cationic and non-ionic polymeric surfactants. This study was conducted in phases. The first phase involved the extraction of coconut fiber, and the second phase involved pre-mordanting the fiber with surfactants. The third stage is the dyeing process, which has variations in pH 3, 7, and 9. The evaluation results show that cationic surfactants have the potential to be used as a mordant and provide an increased anti-bacterial effect on processed fabrics. The optimal use of cationic surfactants was obtained using a concentration of 9 g/L and pH 7 for the cotton dyeing process. The optimum concentration was obtained at 9 g/L for the silk dyeing process, and the dyeing pH was 3.
CONVERSION OF PINEAPPLE PEEL GLUCOSE INTO BIOETHANOL USING SIMULTANEOUS SACCHARIFICATION AND FERMENTATION (SSF) METHOD AND SEPARATE HYDROLYSIS AND FERMENTATION (SHF) METHOD Saragih, Hasri Tri Maya; Sembiring, Jhony Hartanta; Ginting, Elfrida
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.50581

Abstract

This study aims to determine the bioethanol yield and characteristics from pineapple peel with two methods such as Simultaneous Saccharification and Fermentation (SSF) and Separate Hydrolysis and Fermentation (SHF). The percent yield of bioethanol produced from the fermentation of pineapple peel (Ananas comosus) with the Simultaneous Saccharification and Fermentation method was 63.50%, while the yield of bioethanol from the Separate Hydrolysis and Fermentation method was 58.75%. The physical characteristics of bioethanol pineapple peel waste using Simultaneous Saccharification and Fermentation method has a density of 0.8237 w/v whilst with Separate Hydrolysis and Fermentation is 0.8858 w/v. Furthermore, viscosity of bioethanol using Simultaneous Saccharification and Fermentation is 1.05 Cp whereas using Separate Hydrolysis and Fermentation is 1.02 Cp. Pineapple peel bioethanol method of Simultaneous Saccharification and Fermentation has concentration of 13% while Separate Hydrolysis and Fermentation method has concentration of 7.92%. FTIR spectra from SHF bioethanol missing the peak correlated with CH, CH3, and CO. These missing peaks is due to the high percentage of water. Furthermore, bioethanol from SSF method showed peaks corresponding to CH, CH3, and CO functional groups. It can be concluded that SSF method give bioethanol with optimum result.  
SYNTHESIS OF POROUS CARBON MATERIAL PROPYLENE MEDICAL MASK AS ADSORBENT HEAVY METAL IRON (Fe) IN WATER EX-TIN MINING BANGKA BELITUNG Amelia, Addela; Putri, Faizah Alivia; Widia; Adelia, Della; Alkasiyah; Fabiani, Verry Andre
Jurnal Kimia Riset Vol. 9 No. 1 (2024): June
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v9i1.50750

Abstract

 Bangka Belitung Islands Province faces severe environmental challenges, exacerbated byillegal tin mining activities leading to heightened pollution levels, particularly in stagnantwater within former tin mining holes, reaching depths of up to 40 meters. The presence ofiron metal (Fe) in this water poses a health risk, potentially damaging intestinal walls andcompromising lung function upon ingestion. This study presents a novel approach to addressthis issue by synthesizing porous carbon material from propylene waste sourced frommedical masks. The process involves initial sulfonation for sterilization and pore sizeenhancement, followed by activation using KOH and carbonization at 750 °C.Characterization methods validate the successful synthesis, including FTIR highlightingpolypropylene groups at 822 cm-1, XRD indicating graphite carbon with high crystallinity,and SEM exhibiting rod shapes and cavities at 5,000í— magnification. The adsorption testdemonstrates outstanding performance, with porous carbon exhibiting a 100% adsorptionefficiency in purifying water, eliminating odors, and reducing iron (Fe) levels. Thisinnovative method effectively reduces iron levels in stagnant water environments, providinga sustainable solution to environmental pollution, particularly in Bangka Belitung.  
STUDY MOLECULES DOCKING OF ALKALOIDS IN KRATOM ON SEROTONIN TRANSPORTER (SERT), NOREPINEPHRINE TRANSPORTER (NET), AND MONOAMINE OXIDASE (MAO) Irawan, Dandi; Wijianto, Bambang; IH, Hariyanto
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.50785

Abstract

Kratom (Mitragyna speciosa Korth) is a tropical plant originating from Southeast Asia that predominantly contains alkaloid compounds and can potentially maintain levels of monoamine compounds in the body to treat depression. The study aimed to examine the potential of 8 alkaloid compounds in kratom as antidepressants towards four target proteins: Serotonin Transporter (SERT), Dopamine Transporter (DOPAT), Leucine Transporter (LEUT), and Monoamine Oxidase (MAO) via molecular docking. The Pyrx program is used with exhaustiveness 106 as the protocol, and the grid is adapted to the active site of each receptor. The affinity values "‹"‹of the alkaloid compounds in kratom are mitragynine, 7-hydroxy mitragynine, speciociliatine, paynantheine, speciogynine, corynantheidine, mitraciliatine, and 9-hydroxycorynantheidine, for MAO were -7.1, -6.1, -5.7, -6.7, -5.7, -7.7, -5.7, and -5.7 kcal/ mole. All compounds bind to amino acid residues in the target protein through hydrogen and pi (Ï€) bonds. All the tested alkaloid compounds have the potential to be re-uptake inhibitors SERT, DOPAT, LEUT, and Monoamine Oxidase (MAO).
DEGRADATION OF TETRACYCLINE BY FLOATING PHOTOCATALYST TiO2/Ni-COCONUT FIBER Putri, Lavena Imelda; Agustiawan, Deri; Sugandi, Didiek; Arfida, Khaizurani; Mardhatilla; Wahyuni, Nelly
Jurnal Kimia Riset Vol. 8 No. 2 (2023): December
Publisher : Universitas Airlangga, Campus C Mulyorejo, Surabaya, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20473/jkr.v8i2.50848

Abstract

The photocatalyst process involves light (photons) as an energy source and catalysts such as TiO2 to accelerate the reaction. Efforts are made to reduce the band gap energy of TiO2 by shifting the absorption towards visible light using metal cation doping, such as Ni2+, and they can float on the surface with coconut fiber. XRD characteristics with TiO2 diffractogram experienced a 2θ shift as an indication that Ni has entered the TiO2 structure and seen some peaks decreased in intensity after being embedded with coconut fiber as an indication that TiO2/Ni has successfully attached to the fiber. The band gap energy on TiO2 is 3.21 eV with a wavelength of 386.5 nm in UV light. TiO2/Ni-coconut fiber experienced a shift in band gap energy to 3.09 eV with a wavelength of 400.9 nm, which is in visible light. This indicates that Ni has successfully entered the TiO2 structure. The TiO2/Ni catalyst embraced with coconut fiber has a higher degradation activity than the catalyst without an embrainer, with a percent degradation of 28.66% for 120 minutes of irradiation. This is influenced by the amount of light that can be absorbed during the photocatalysis process.  

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