Results in Journal Jurnal Kimia Sains dan Aplikasi: 496
(searched for: journal_id:(1579377))
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 255-260; doi:10.14710/jksa.23.7.255-260
The Centrifugal liquid Membrane (CLM) method, which provides an ultra-thin two-phase liquid membrane system in a rotating glass cell, was successfully applied to Green Synthesis from Polyscias scutellaria (PS) capped gold nanoparticles (AuNPs-PS) using a Mangkokan leaf (Polyscias scutellaria) extract as a reducing agent and stabilizer in the hexane-water system. PS extract in hexane fraction as the organic phase has a UV absorption spectrum at the maximum wavelength, λmax of 220 nm, while the precursor of HAuCl4 solution as an aqueous phase has an λmax of 214 nm. Investigation of AuNPs-PS formation was carried out at various concentrations of Mangkokan leaf extract concentration; i.e., 0.001 0.003; 0.005; 0.007 and 0.009%, while the reaction was carried out at various rotational speeds of 5,000-9,000 rpm. The formation and stability of AuNPs-PS were observed from the phenomenon of surface plasmon resonance (SPR) and absorbance changes as measured by a UV-Vis spectrophotometer. The results of measurements using CLM-Spectrophotometry shows the formation of AuNPs-PS in the hexane-water system at λmax of 534 nm.
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 276-282; doi:10.14710/jksa.23.8.276-282
Functional drinks based on red betel leaf extract have antioxidant activity, but they still have a bitter taste. This study aims to determine the effect of microencapsulation on phenol content, antioxidant activity, and sensory quality of functional drinks based on betel leaf extract. Microencapsulation of functional drinks was made using maltodextrin coatings with concentrations of 10% and 20%. Antioxidant activity was tested by the CUPRAC method. The ready to drink (RTD) functional drink has a total phenolic content and antioxidant activity of 782.30 ± 2.54 mg GAE/g and 1660.19 ± 31.67 µmol Tr/g, respectively. These values are higher than microencapsulated functional drinks with maltodextrin (MM). The microencapsulated functional drink with 10% maltodextrin coating (MM10) is the chosen formulation since it has the smallest particle size (1.283 µm), total phenolic content of 12.90 ± 0.01 mg GAE/g and antioxidant activity of 189.41 ± 1.88 µmol Tr/g. Microencapsulated functional drinks provide sensory quality that is not significantly different (p
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 244-248; doi:10.14710/jksa.23.7.244-248
The rapid development of the batik industry can pollute water resources and become an increasingly severe problem. This research studies the adsorption-desorption of naphthol blue-black (one of the dyes in batik liquid waste) by magnetite modified humic acid (HA-Fe 3 O 4 ). The adsorption isotherm was studied using the Langmuir and Freundlich isotherm models. Meanwhile, desorption agents used in this study were distilled water and hydrochloric acid. The results show that the adsorption isotherm followed the Langmuir adsorption model with a maximum adsorption capacity of 2.41 mmol/g. Desorption studies show that the desorption efficiency of naphthol blue-black on HA-Fe 3 O 4 is 0.058% and 5.86% in the desorption agent of distilled water and HCl (1 M)
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 238-243; doi:10.14710/jksa.23.7.238-243
Indonesia has a diversity of hot spring as a habitat of bacteria. One of the hot springs is Natar hot spring, Lampung. This study is to report the characteristics of a bacterium called Nat1 isolate that produces amylase to degrade raw starch from Natar hot spring. Water samples were taken from hot springs with a temperature of 45°C and a pH of 7.0. Nat1 was isolated by screening on the medium of Starch-Luria Bertani at 37°C. Its amylase-producing bacteria showed an optimum amylolytic activity of a crude enzyme of Nat1 isolate in soluble starch was 267.2774 U/mL at 60°C. Genotypic identification results using the 16S rRNA gene showed that the Nat1 isolate is identified as Panninobacter phragmatetus. A crude enzyme of Nat1 isolate showed a novel amylase ability and could degrade the raw starch substrates, such as corn and sago, with the amount of reducing sugar for each raw starch, 37.0688 µmol/mg, and 24.2697 µmol/mg. In conclusion, Nat1 amylase is potentially used in industry for its ability to degrade raw starch directly.
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 234-237; doi:10.14710/jksa.23.7.234-237
Ethyl acetate fraction from Swietenia macrophylla was reported to have toxicity against the larvae of Artemia salina shrimp larvae. However, there areno reports aboutS. macrophylla, which can inhibit human breast cancer cells MCF-7. Therefore, this study aims to evaluate S. macrophyllaextract's cytotoxicity using human breast cancer MCF-7 cells assay, followed by confirmation of its toxicity using brine shrimp lethality assay. The most active fraction obtained from the ethyl acetate extract of S. macrophylla showed 76.49% inhibition at 50 µg/mL (IC50=34.11 µg/mL). At the same time, the most active fraction may contain a mixture of limonoid compounds after LCMS analysis. The most active fraction obtained from ethyl acetate extract of S. macrophylla showed 76.49%
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 249-254; doi:10.14710/jksa.23.7.249-254
Modification of silica xerogel with TMCS (trimethylchlorosilane) reagent has been carried out to improve the hydrophobicity of silica xerogel. Silica xerogel was synthesized based on the sol-gel method using sodium silicate as a precursor, and citric acid as a catalyst, with a mole ratio of sodium silicate and citric acid, was 0.172: 0.004. The sol-gel process was carried out through several stages, i.e., hydrolysis and condensation of sodium silicate to form sol, gelation (sol transition to gel), aging, and drying. Surface modification was performed by studying the effect of TMCS: methanol: petroleum benzine volume ratio of 0.5:1:1, 1:1:1, 1.5:1:1, 2:1:1, and 2.5:1:1 on the characteristics of silica xerogel synthesized. FTIR, SEM, and GSA characterized the synthesized results. The results of FTIR characterization on silica xerogel with volume ratios of 2:1:1 and 2.5:1:1 indicate the presence of the Si‑C group absorption at a wavenumber of 848.68 cm-1 which shows that the formation of silyl groups on the modified silica xerogel surfaces occurs at a TMCS: methanol: petroleum benzine ratio of 2:1:1 and 2.5:1:1. SEM results indicate that the silica xerogels produced are porous. Meanwhile, the GSA analysis results show that the pore size distributions are in the mesoporous region with an average pore radius of 8-13 nm. The greater the volume of TMCS used, the higher the surface area, and the resulting xerogel’s hydrophobicity. Based on the contact angle and seeped time test, the highest hydrophobicity is produced by the material synthesized at a TMCS: methanol: PB volume ratio of 2.5:1:1 with a contact angle of 116.346°.
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 189-195; doi:10.14710/jksa.23.6.189-195
Syzygium polyanthum leaf extract and Syzygium cumini herbs extract have been reported to have antidiabetic activity. This study aimed to predict the molecular target of chemical constituents of S. polyanthum and S. cumini as well as study their interactions with various macromolecular targets of an antidiabetic agent. Molecular docking of all ligands was studied using the Autodock Vina program in PyRx, and the results are presented as binding affinity values (kcal/mol) of ligand against the protein. PyMOL is used to visualize the 3D molecular of docked conformation and ligand-protein interactions. The predicted pharmacokinetic parameters were obtained by SwissADME. Delphinidin-3-gentiobioside and isoquercitrin are predicted to have good interaction with DPP-4 and α-glucosidase, respectively. However, they are predicted to have poor absorption properties. Quercetin and kaempferol are predicted to have good interaction with PTP1B and glucokinase and showed good pharmacokinetic properties.
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 147-151; doi:10.14710/jksa.23.5.147-151
This study was aimed to examine the production of microcrystalline cellulose (MCC) from tapioca solid waste (TSW), using HCl hydrolysis with various concentrations, i.e., 2 N, 2.5 N, 3 N, and 3.5 N. MCC was produced by delignifying the TSW with NaOH 20%, and bleaching with NaOCl 3.5% to produce α-cellulose, and subsequently hydrolyzing α-cellulose with three different HCl concentrations to produce MCC. The physicochemical properties of MCC were then analyzed, including Scanning Electron Micrograph (SEM), X-ray diffraction (XRD), and FTIR spectra. The results showed that hydrolysis with 2.0 N HCl resulted in a higher yield of 61.28%, α-cellulose content of 56.33%, moisture 6.25%, pH of 6.54; ash 0.23%, and water solubility 0.34%. SEM analysis showed the morphology and size of the MCC produced were like those of a commercial MCC (Avicel PH101), while the XRD analysis showed the higher concentration of HCl gave rise to an increased crystalline index. FT-IR spectrum analysis indicated that TSW, MCC produced, and commercial MCC had similar functional groups.
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 203-208; doi:10.14710/jksa.23.6.203-208
Plastic derived from petroleum is challenging to degrade and pollute the environment. There are alternatives to making biodegradable plastics to reduce the adverse effects of plastics on the environment. This study aims to utilize dragon fruit peel waste as a material for making bioplastic. Plastic characterization was carried out by FTIR analysis to determine the functional groups contained in bioplastics. The results showed that dragon fruit peel could be extracted by HCl solution, and the pectin yield is 11%. Extracted pectin was used to make bioplastics with and without the addition of ethylene glycol. The results showed that moisture content of bioplastics of dragon fruit peel pectin is 5.71–12%, while dragon fruit peel pectin and ethylene glycol are 2.86–5.71%. FT-IR spectra showed that the bioplastics from dragon fruit peels belong to the pectin group, which produces carbonyl absorption at 1636–1628 cm-1 and stretching C-O stretch at 1098–1101 cm‑1.
Jurnal Kimia Sains dan Aplikasi, Volume 23, pp 209-215; doi:10.14710/jksa.23.6.209-215
Utilizing lignocellulosic biomass into valuable products, such as chemicals and fuels, has attracted global interest. One of lignocellulosic biomass, palm oil empty fruit bunch (EFB), has major content of cellulose (30-40%), which is highly potential to be a raw material for fermentable sugar production. In this research, a series of sulfonated carbon catalysts with various concentrations of sulfuric acid (H2SO4, 10-30 v/v%) solutions have been successfully prepared and applied for a single stage of heterogeneous acid-catalyzed hydrolysis over microcrystalline cellulose and EFB under moderate temperature condition and ambient pressure. The catalysts’ physical and chemical properties were characterized by using a Thermogravimetric Analyzer (TGA), X-ray diffractometer, surface area analyzer, and Fourier-transform infrared spectrophotometer. The characterization results showed that sulfonated carbon had relatively similar physical properties with the parent of active carbon. The hydrolysis activity of sulfonated carbon catalysts gave various Total Reducing Sugar (TRS). The effects of sulfate loading amount in catalyst samples and various ionic liquids were investigated. The hydrolysis of pure microcrystalline cellulose powder (Avicel) using 30%-sulfonated carbon (30-SC) catalyst in 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) ionic liquid at 150°C yielded the highest TRS of 16.11%. Subsequently, the catalyst of 30-SC was also tested for hydrolysis of EFB and produced the highest TRS of 40.76% in [BMIM]Cl ionic liquid at 150°C for 4 h. The obtained results highlight the potential of sulfonated carbon catalysts for hydrolysis of EFB into fermentable sugar as an intermediate product for ethanol production.