Jurnal Kimia Valensi
Not a member yet
402 research outputs found
Sort by
Development of a Low-Cost Reflectance Visible Spectrophotometer with Chemometrics for Curcuma xanthorrhiza Roxb. Quality Control
Full text linkA simple, portable visible reflectance spectrophotometer was developed for classifying the quality of Curcuma xanthorrhiza Roxb. The device was assembled using consumer electronic components: an LED as the light source, a DVD optical layer as the diffraction grating, and a webcam as the detector, with web-based software (Spectral Workbench) as the signal processor. The spectrophotometer\u27s performance was evaluated using standard Sudan III samples and powdered C. xanthorrhiza samples from two quality classes (A and B). Spectral data were analysed using principal component analysis (PCA) and partial least squares (PLS) regression. PCA successfully grouped Sudan III samples by concentration and classified C. xanthorrhiza by curcuminoid content. A PLS regression model was developed for quantifying Sudan III, yielding R² values of 0.9909 for both calibration and cross-validation, with RMSEs of 0.3821% and 0.4152%, respectively. The results closely matched those from a commercial spectrophotometer. A PLS-discriminant analysis (PLS-DA) classification model for C. xanthorrhiza was also developed, achieving sensitivity and specificity values of 1. Additionally, semi-quantitative parameters such as decision limit (26.15% B), detection capability (41.06% B), and unreliability range (26.15–41.06% B) were calculated. The classification model showed strong sensitivity, specificity, and detection capabilities within acceptable limits. These findings suggest that this low-cost reflectance spectrophotometer, combined with chemometric methods, holds promise as a practical tool for the quality control of raw herbal materials
Chemical Characterization and Antibacterial Activities of Bio-oil from Durian Shell Pyrolysis
Full text linkFoodborne bacteria cause food spoilage, usually Staphylococcus aureus and Escherichia coli. Thus, synthetic preservatives are employed in food preservation to prevent food spoilage caused by microorganisms. Excessive use of synthetic preservatives can cause disease. Bio-oil has become a natural preservative because of its high phenolic content. However, bio-oil still requires purification because the initial bio-oil (grade 3) still contains carcinogenic compounds that are dangerous for consumption. Therefore, this study aims to determine the components of the bio-oil compound after purification and its effectiveness as an antibacterial. Durian shell (DS) is pyrolyzed in a heating reactor without oxygen at a temperature of 330–600ºC (flow rate 6ºC/minute) with a 2-3 cm material size. Furthermore, bio-oil purification includes stages of filtration using activated zeolite, fractional distillation at 70–200ºC (grade 2), and filtration using activated charcoal (grade 1). Bio-oil purification includes stages of filtration using active zeolite and activated charcoal (grade 2), and fractional distillation at a temperature of 150–200ºC (grade 1). Based on Gas Chromatography-Mass Spectrometry (GC-MS) analysis, grade 2 and grade 1 contain the major compounds 1,4-dimethyl-1h-imidazole and acetic acid. The research showed that bio-oil grades 1 and 2, when used at a 30% concentration, exhibit antibacterial strong effects against Staphylococcus aureus and Escherichia coli. These findings suggest that bio-oil grades 1 and 2 could be valuable natural preservatives
Characterization and Application of Hydroxyapatite From Chicken Egg Shell with Green Template as a Potential Drug Delivery System
Full text linkHydroxyapatite (HAp) is a calcium phosphate biomaterial widely studied in the medical field because of its good biocompatibility properties. This study aims to identify the effect of increasing variations in banana peel template concentration on the characteristics of hydroxyapatite so that it has the potential as a drug delivery system. This study includes the characterization and application of the potential of the hydroxyapatite drug delivery system with the addition of variations in the concentration of green template. Then, hydroxyapatite was characterized using X-ray diffraction (XRD) and a surface area analyzer (SAA). This study\u27s results indicate that adding a banana peel template affects the characteristics of hydroxyapatite. The higher the template concentration, the smaller the crystallite size, pore size, pore volume, and surface area, but the degree of crystallinity is greater. The results showed that the characterization of hydroxyapatite K15% with a crystal size of 34.73 nm, a degree of crystallinity of 89%, a pore size of 7.2178 nm, a surface area of 30.111 m2/g, and a pore volume of 0.1145 cc/g. The results of the study of the potential of the drug delivery system obtained a loading efficiency value of 67% for ibuprofen. However, the ibuprofen release process results at time intervals tend to be unstable
Extraction and Physicochemical Characterization of Pectin from Noni (Morinda citrifolia) Fruit
Full text linkNoni (Morinda citrifolia) is a popular plant in Asian countries and has great potential as pectin source for thickening agents in food products. In general, ethanol has been widely used to precipitate pectin, but the proportion can affect the quality of the product. Therefore, this study aimed to characterize the physicochemical properties of pectin from noni fruit. Extraction was performed using 0.1 N HCl at pH 1.5 and heated at 80°C for 15 min, followed by precipitation with different proportions of 96% ethanol including A (1:1), B (1:2), and C (1:3) v/v, while commercial orange pectin was used as a reference. The results showed that all pectin extracted belonged to the high methoxyl category. The FTIR spectra confirmed the presence of important functional groups including OH-hydroxyl, CH3-saturated aliphatic methyl, C=O carbonyl, and -O- cyclic ether. Furthermore, the crystalline and amorphous structures of noni pectin were confirmed by X-ray diffraction observation. The highest yield was achieved using the proportion of 1:3, followed by 1:2, and 1:1 on a wet basis. The MeO and AUA content of sample B (1:2) were relatively similar to those of the reference. Based on extraction results, noni possesses good characteristics and has the potential for commercial pectin production
Modification & Characterization of Activated Carbon Impregnated with KCl, Na2S, and KI for Enhancing Mercury (Hg) Removal from Natural Gas
Full text linkModified activated carbon (MAC) has been synthesized and characterized to enhance mercury (Hg) removal from natural gas. MAC was modified by impregnating it into KCl, Na2S, and KI to introduce Cl-, S-, and I- elements. SEM-EDX, FTIR, and SAA were used to characterize the AC and MAC. The isotherm and adsorption capacity were studied using the mercury gas standard. The results of SEM-EDX analysis show that the impregnation method is proven to produce MAC containing elements Cl, S, and I with mass % of 2.78% Cl, 0.76% S, and 39.60% I. The surface area is 421.91 m2/g, the total pore volume is 0.386825 cc/g, and the average pore size is 1.83369 nm. Group functions are -OH, C=C, C=O, C-O, and vibrations at the wavelength number 617.81 cm-1, which the impregnation agent forms. The mechanism for absorbing mercury gas into MAC follows the Freundlich isotherm model, with a coefficient of determination (R2) of 0.996. The adsorption capacity on MAC increased 57 times compared to unmodified activated carbon (AC) from 5540.60 to 315730.64 ng/g, with an efficiency maximum of 100%. The MAC has been proven to enhance mercury adsorption from natural gas with an efficiency of 78.6%
Hybrid CaO/ZnFe2O4 Modified with Al2O3 as a Green Catalyst for Biodiesel Production from Waste Cooking Oil
Full text linkIn this work, biodiesel was produced from waste cooking oil (WCO) via a green catalyst of CaO-ZnFe2O4 modified Al2O3. The catalyst was characterized using Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray (EDX), SEM-mapping, Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM) analyses. The catalyst performance was studied in the transesterification reaction of WCO conversion to biodiesel. The catalytic activity increased with the combination of nanoparticles effect and support catalysts obtained biodiesel yield of nano-Al2O3, nano-CaO, ZnFe2O4, CaO-ZnFe2O4, and CaO-ZnFe2O4/Al2O3 is 36.86%, 67.16%, 74.83%, 86.54%, and 93.41%, respectively. The best biodiesel yield was 93.41% with a mass ratio of Al2O3 to CaO-ZnFe2O4 (2:1). The physicochemical properties (acid number, density, kinematic viscosity, flash point, and cetane number) of biodiesel under the optimal conditions agreed with the ASTM standard. These results show that the developed nanocomposite has great potential to reduce biodiesel production costs because derived from WCO. In conclusion, CaO-ZnFe2O4 modified Al2O3 as a catalyst has a high potential for biodiesel production on a large scale
Green Synthesis, Characterization, and Applications of Aluminum Oxide Nanoparticles Using Aqueous Extract of Clove
Full text linkIn this work, γ-Al2O3NPs were successfully biosynthesized, mediated aluminum nitrate nona hydrate Al(NO3)3.9H2O, sodium hydroxide, and aqueous clove extract in alkali media. The γ-Al2O3NPs were characterized by different techniques like Fourier transform infrared spectroscopy (FT-IR), UV-Vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy–dispersive x-ray spectroscopy, transmission electron microscope (TEM), Energy-dispersive X-ray spectroscopy (EDX), and atomic force microscopy (AFM). The final results indicated the γ-Al2O3NPs nanoparticle size, bonds nature, element phase, crystallinity, morphology, surface image, particle analysis – threshold detection, and the topography parameter. The identified of γ-Al2O3 bands were detected by the FT-IR spectroscopy. The UV-visible spectrum of γ -Al2O3NPs exhibited an absorption band and (energy gap, Eg = 4.91 eV). It was found that the size range of nanoparticles was (28-37) nm and cubic with agglomerated particles. Antimicrobial activity study showed an excellent inhibition activity of γ-Al2O3NPs against Escherichia coli negative (G-), staphylococcus aureus, positive (G+), and Candida albicans fungal. The effectiveness of the adsorption experiment was proven on binary metal ions, such as cobalt, nickel, and copper, by removing them from water using a nanostructured active surface of γ-Al2O3NPs. The efficiencies removal of Co+2, Ni+2, and Cu+2 ions were 93.22%, 87.49%, and 93.17% respectively
Synthesis and Characterization of Low Molecular Weight Irradiated Chitosan in Various Water Levels and Gamma-Ray Doses
Full text linkChitosan is a biopolymer derived from marine animal shell waste that exhibits numerous pharmacological activities. However, its high molecular weight limits the application in various fields due to its low solubility. Therefore, this study aims to synthesize low molecular weight chitosan using varying water content and doses of gamma irradiation. To initiate chitosan degradation, H2O (5 and 10 mL) was added, followed by gamma ray irradiation at doses of 5 and 10 kGy. The Molecular Weight (MW) of degraded chitosan was determined using Gel Permeation Chromatography (GPC), while Fourier Transform Infrared Spectroscopy (FTIR) was used to characterize the functional groups and degree of deacetylation of chitosan. The study found that the molecular weight of irradiated chitosan decreased as the irradiation dose and H2O addition increased. The addition of 10 mL of water and gamma irradiation at a dose of 10 kGy has been found to reduce the molecular weight of chitosan to 118 kDa, with a high deacetylation degree of 86.78%. The FTIR analysis showed no significant changes in the functional groups, indicating that gamma irradiation did not affect the structure of chitosan
Cloning of the GOX-Xho Gene IPBCC 08.610 into Plasmid pTA2 and Its Characterization
Full text linkGlucose oxidase (GOX) from Aspergillus niger catalyzes the oxidation of β-D-glucose to δ-gluconolactone and hydrogen peroxide, making it valuable for industrial applications. Intracellular GOX exhibits higher activity than its extracellular counterpart. This study focuses on enhancing the extracellular production of GOX through recombinant DNA technology. This study aimed to reconstruct the GOX gene by adding XhoI sites at both ends, inserting a glu-ala-glu-ala spacer at the 5\u27 end, and introducing an XbaI site at the 3\u27 end. These modifications facilitate the cloning of the GOX-Xho gene into the pTA2 vector and its subsequent ligation into the pPICZαB expression vector, allowing for extracellular production of GOX through fusion with the α-mating factor (α-MF) signal peptide. The GOX-Xho gene was successfully amplified, cloned, and characterized. The pTA2-GOX-Xho recombinant plasmid was verified through sequencing and restriction analysis, confirming the present and correct orientation of the 1797 bp GOX-Xho gene. However, sequencing revealed several point mutations, necessitating further computational analysis to predict their impact on the enzyme\u27s structure and function before recombinant protein expression
Synthesis, Characterization, Molecular Docking Studies and Pharmaceutical Evaluation of some Novel [1,2,4]Triazolo[3,4-B][1,3,4]Thiadiazole
Full text linkA new series of fused [1,2,4]Triazolo[3,4-b][1,3,4]thiadiazole 4a-4e have been synthesized by many steps. Firstly, benzohydrazide [1] has been synthesized from the reaction of methyl benzoate with hydrazine hydrate. Secondly, the cyclization reaction of benzohydrazide with carbon disulfide in the presence of potassium hydroxide produced 5-phenyl-1,3,4-oxadiazole-2-thiol[2]. Thirdly,5-phenyl-1,3,4-oxadiazole-2-thiol[2] was treated with potassium hydroxide using pyridine to give 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol. Finally, the fused [1,2,4]Triazolo[3,4-B][1,3,4]Thiadiazole 4a-4e were synthesized from the reaction of 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol[3], with various aromatic aldehydes. The structures of the newly synthesized compounds have been confirmed based on spectral studies. The new novel compounds exhibited anticancer activity docking with C-Met tyrosin kinase receptor as shown by their docking scores ranging between -3.506 to -4.468 Kcal/mol as compared to standard crizotinib binding affinity is to -3.211Kcal/mol for anticancer efficiency. The newly synthesized triazole thiadiazole derivatives were evaluated for their in-vitro cytotoxic activity against human cancer cell lines. It was found that compounds 4b and 4c showed higher cytotoxicity against the MCF-7 cell line and no cytotoxic effect on normal cell line HdFn