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INDONESIA
Indonesian Journal of Chemical Science
Published by Universitas Negeri Semarang
ISSN : 22526951     EISSN : -     DOI : -
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry
Arjuna Subject : -
Articles 830 Documents
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Green Synthesis of ZnO Nanoparticles with Papaya Leaf Extract (Carica papaya L.) as a Reductor and its Application on Cotton Fabrics
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.52526

Abstract

ZnO nanoparticles have great applications such as photocatalysts and have antibacterial activity and hydrophobic properties. In this research, green synthesis with papaya leaves extracts as a reducing agent for ZnO nanoparticles that applicated on cotton fabric with pad dry-cure method. ZnO nanoparticle coating was carried out at concentrations of 3%, 6%, and 9%. Characteristics resulting from FT-IR and XDR identified ZnO nanoparticles from the synthesis with papaya leaf extract have a crystallinity level of 76.97% with a crystalline size of 39.60 nm. Application of ZnO nanoparticles on fabric showed an increase in the hydrophobic properties of the fabric and good antibacterial activity on the Staphylococcus aureus (gram-positive bacteria) and Escherichia coli (gram-positive bacteria). The highest contact angle of the ZnO nanoparticle-coated fabric is shown in the concentration of 3% which is 113°. The highest antibacterial activity was shown at the concentration of the largest 9% in Staphylococcus aureus bacteria with an area of inhibition of 23.7 mm and in Escherichia coli with an area of inhibition of 8.3 mm.
Determination of Total Phenolic, Total Flavonoid and Antioxidant Activity of Batak Onion Extract (Allium chinense G. Don)
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.54669

Abstract

Free radicals trigger the emergence of degenerative diseases. This disease can be suppressed by antioxidant compounds that are able to destroy and neutralize free radicals. Antioxidants can be found in the genus Allium or onions, one of which is the Batak onion. The purpose of this study was to determine total phenolic, total flavonoid and antioxidant activity of Batak onion extract. Sample extraction was carried out by multilevel maceration technique using three solvents with different polarities, namely dichloromethane, ethyl acetate and 96% ethanol. The stage of sample testing included analysis of total phenolics using the Folin-Ciocalteu method, total flavonoids were determined by the AlCl3 colorimetric method and antioxidant activity determined by the DPPH method (2,2-diphenyl-1-picrylhydrazyl). The results showed that dichloromethane extract and ethyl acetate extract did not contain flavonoid and phenolic compounds. The total content of phenolic compounds in 96% ethanol extract is 1,6800 mg GAE/g extract (classified as low). The total content of flavonoid compounds in 96% ethanol extract is 1,5467 mg QE/g extract. The antioxidant activity is indicated by IC50 value in 96% ethanol extract which was 248,9503 ppm (classified as medium) and dichloromethane extract of 412,4689 ppm (weak).
Synthesis of Cellulose Esters through an Oxidative Esterification of Cellulose with Cinnamaldehyde in Ionic Liquid and External Bases
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.55649

Abstract

Cellulose is a polysaccharide consisting of glucose linked by -1,4 glycosidic bonds in straight chains with the formula (C6H10O5)n. Cellulose modification uses long-chain hydrocarbon substituents from essential oils which can increase the added value of cellulose and essential oils. Oxidative esterification reaction is an efficient method for modifying cellulose with unsaturated α,β aldehyde compounds, one of which is cinnamaldehyde. Ionic liquid acts as a catalyst and solvent to accelerate the oxidative esterification reaction. This research was conducted to determine the effect of cinnamaldehyde on the synthesis of cellulose esters and the addition of an external base to the synthesis of cellulose esters. The synthesis of cellulose esters was carried out through an oxidative esterification reaction of cellulose and cinnamaldehyde which was added with ionic liquid and an external base for 6 hours at 80°C. The tests include FT-IR characterization to determine whether or not a carbonyl peak is formed, Differential Thermal Analysis/Thermal Gravimetry Analysis (TGA) and Differential Scanning Calorimetry (DSC) for thermal analysis and solubility test with acetone and DMSO solvents. The results showed that there was a peak at the wave number of 1700 cm-1 namely the C=O ester group which identified the success of the cellulose ester synthesis reaction with a degree of substitution (DS) value of 2.47.
Concentration Effect of Brotowali Stem (Tinospora Crispa (L.)) in Ethanol Extracts on the Α-Glukosidase Enzyme Inhibition
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.55914

Abstract

Antidiabetic oral use in the long run will have an effect on the body, thus providing a need for such medications as herbal plants. Brotowali plants are effective in treating diseases such as diabetes because they contain active borapetoxide c and borappentol B compounds. The purpose of the study is to identify the effect of inhibitor activity α - glucosidase against inhibition of the enzyme α - glucosidase using variations in the concentration of ethanol extract of brotowali plant by measuring the absorbance of p-nitrophenol with UV-Vis spectrophotometry with a wavelength of 400 nm. According to the results of testing the inhibition activity of brotowali ethanol extract at different concentrations showed an IC50 value of 1,663 μg / mL, lower when compared to acarbosa as a comparison that shows an IC50 value of 246 μg / mL. The highest inhibition value of α-glucosidase occurs at the extract dilution concentration of 2000 ppm which is 78.065% and the lowest at the extract dilution concentration of 400 ppm which is 50,098%. Based on the results, it might be drawn to the conclusion that there is an effect of the concentration of brotowali stem extract on inhibition of the enzyme α-glucosidase. If the higher concentration of extract is the lower the value of the injection, causing the higher the value of α-glucosidase inhibitor. If the lower concentration of extract is, the lower the value of inhibitors or inhibitory activity.
Formulation of Flavor Enhancer from Shiitake Mushroom (Lentinula edodes) with the Addition of Mackerel Fish (Scomberomorus commerson) and Dregs Tofu Hydrolysates
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.55925

Abstract

A flavor enhancer is a food additive that can give a certain taste. Synthetic/artificial flavor enhancers are currently widely used in public, but excessive use can have an impact on health problems, so they can be replaced by using natural flavor enhancers. This study aims to make natural flavorings with the basic ingredients of shiitake mushrooms, mackerel fish hydrolyzate, and tofu dregs hydrolyzate. The method used in this study was a Completely Randomized Design. The flavoring was done by varying the composition into 3 formulas with successive ratios of shiitake mushrooms, mackerel fish hydrolysate, and tofu dregs hydrolysate are 1:2:2, 2:1:2, and 2:2:1 which were then analyzed using the Kruskal Wallis and continued with the Mann-Whitney test and analyzed using the Exponential Comparison Method to determine the best formula. The results showed that formula 3, namely flavoring with a composition ratio of 2:2:1, was the chosen formula based on the assessment in organoleptic tests. The flavoring of formula 3 was then carried out with a proximate test and the results obtained were 10.1% water content, 6.5% ash content, 26.4% protein content, 19.9% ​​fat content, and 18.5% fiber content. Based on the research, it can be seen that the flavoring of shiitake mushrooms with the addition of hydrolyzate of mackerel fish and tofu dregs can be used as a substitute for synthetic flavoring and has good nutritional content.
Synthesis of Cellulose Nanofiber from Palm Oil Empty Fruit Bunches Using Acid Hydrolysis Method
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.55936

Abstract

Nanocellulose comes in a variety of forms, the most common are fibrils or fibers, which contribute to its application in biodegradable products. Because cellulose nanofibers (CNF) have a high strength-to-weight ratio and are biodegradable, they play a significant role in the development of novel materials such as biopolymers. Oil palm empty fruit bunches, which are commonly available in East Kalimantan, were used to make cellulose nanofibers in this research. Other components included in raw materials, such as lignin and hemicellulose, can be removed to isolate the cellulose. The chemical method was chosen over the others since it has been proved to be effective in the isolation of nanocellulose. The composition and morphology of the CNF samples were next examined using FT-IR, SEM, and XRD. From the characterization results, it was found that the size of the nanocellulose fibers ranged from 400 nm - 900 nm. The high crystallinity level of 65% indicates high thermal stability so the CNF can be used for various matters. The results of the FT-IR test showed a peak around 1000-1100 cm-1 which indicated the vibration of the skeletal C-O-C pyranose ring that contributed to the increase in the crystallinity of CNF.
Development of Green Bromination Titration for Determination of Ciprofloxacin Hydrochloride in Different Pharmaceutical Dosage Forms
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.56221

Abstract

Ciprofloxacin Hydrochloride (CIP-HCl) is a second-generation synthetic fluoroquinolone used for a wide range of infectious diseases. This study set out to provide a handy, cost-effective, facile, and eco-friendly analytical technique titrimetric method (method A). The developed titrimetric method is based on the bromination of CIP-HCl by bromine produced in situ by the reaction of acid on the bromate-bromide mixture. Alongside, simple UV-Spectroscopic (method A) from previous literature was conducted. Titrimetric allows the determination over the range of 5.0-70.0 mg CIP-HCl while in UV-spectroscopic, Beer’s law is obeyed in the concentration ranges of 3.5-11.5 μg mL-1. The result of the proposed method was compared statistically with the reference UV-spectroscopic method from the literature. Student’s t-test and F-ratio at 95% confidence level were used for comparison. The result showed no significant differences between the developed method (method A) and the reference method (method B) in regards to accuracy and precision. The developed method and UV-spectroscopic were applied effectively for the determination of the CIP-HCl in three different dosage forms (tablet, infusion, and eyedrops), with three brands for each dosage form.
Fructone Synthesis from Ethanol and Acetic Acid
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.57070

Abstract

Fructone (Ethyl 2-methyl-1,3-dioxolan-2-acetate) is a perfume ingredient with an apple scent. This study aims to synthesize fructone through the steps of synthesizing ethyl acetate from ethanol and acetic acid, synthesizing ethyl acetoacetate from ethyl acetate through the Claisen condensation reaction, and synthesizing fructone through the acetylation reaction of ethyl acetoacetate with ethylene glycol. Determination of the optimum conditions for the reaction is done by varying the temperature, reagents, catalysts, and time. The reaction products were analyzed by GC and GCMS. It was found that the conversion of ethyl acetate with H2SO4 catalyst and p-toluene sulfonic acid (PTSA) at 75 oC was almost the same, namely 96.63% for H2SO4 catalyst and 96.02% for PTSA catalyst. The optimum conditions for the synthesis of ethyl acetoacetate at a temperature of 82 oC, mole ratio of ethyl acetate, ethanol, and sodium 2:1:1, reaction time for 2 hours with ethyl acetoacetate conversion of 91,55%. The fructone formation reaction using the cyclohexane-water azeotrope technique gave more product than without using the azeotrope technique. The optimum condition for the synthesis of fructone compounds at a temperature of 78 oC, the ratio of moles of ethyl acetoacetate, ethylene glycol and H2SO4 catalyst is 1:2:0.06, the reaction time is 2 hours with the resulting fructone conversion of 87.07%.
Activities of Liquid Organic Fertilizer from the Date Juice Waste During Hydroponic Plant Growth
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.57823

Abstract

PT. Herba Emas Wahidatama (Purbalingga) has date palm juice waste as a result of date palm juice that has not been standardized and has expired. Dates juice waste is used as liquid organic fertilizer so that it can be resold and produces less waste residue. This study aims to determine the effect of variations in EM4 volume and fermentation time on levels of C-organic, nitrogen, phosphorus, and potassium liquid organic fertilizer and determine the results of liquid organic fertilizer application on hydroponic plant growth. The method of preparation of liquid organic fertilizer uses a fermentation process with a volume variation of the bio activator EM4 0; 20; 40 mL and fermentation time 7; 14; 21 days. Liquid organic fertilizer analysis methods include the Walkley and Black method (C-organic), Kjeldahl (N-total), spectrophotometry (P-total), and atomic absorption spectrophotometer (K-total). The yield of C-organic content is 25.00-30.43%, nitrogen content is 0.01-0.18%, phosphorus is 0.05-0.09%, potassium is 0.34-0.71%, pH is 4.26– 4.41. With more volume of EM4, organic C- and phosphorus levels increased, and nitrogen and potassium levels decreased. The longer the fermentation time, the C-organic content increased, the nitrogen and phosphorus content decreased, and the potassium level increased and then decreased. The results of the application of liquid organic fertilizer on water spinach plants using the hydroponic wick system did not grow after 10 days of sowing, the plants lasted a week and then withered and died. This is due to more C-Organic than the levels of nitrogen, phosphorus, potassium, and lack of sunlight for photosynthesis so plants experience etiolation symptoms.
Chemometric Analysis of Iron, Manganese, and Zink Contents for Ground Water Quality Assessment around the Candi Industrial Estate of Semarang City
Indonesian Journal of Chemical Science Vol 11 No 3 (2022)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/ijcs.v11i3.58920

Abstract

Water is the most important natural resource for humans and its function cannot be replaced with other compounds. Most people use ground water and surface water to meet their daily needs. Several factory production activities in the Candi Industrial Estate of Semarang have a role in protecting the environment, especially related to pollution of the aquatic environment in the surrounding area. Some of the potential liquid waste that make pollute into the environment such as Iron (Fe), Manganese (Mn), and Zinc (Zn). The purpose of this study was to measure the levels of heavy metals Fe, Mn, and Zn in groundwater around the Semarang Candi Industrial Estate by using chemometric analysis using Principal Component Analysis (PCA) and Cluster Analysis (CA) methods. Data on the levels of Fe, Mn, and Zn have been analyzed by PCA and CA methods using SPSS 22 application software. The results in this study indicate that mostly of water sample from Candi Industrial Estate reliable with clean water quality standard, just there is one area that have the content of heavy metal levels of Fe of 1 mg/L, which means that it is above the standard threshold for clean water quality set by the Regulation of the Indonesian Minister of Health Number 32 of 2017. The results obtained in PCA analysis formed 2 main components, namely PC1 and PC2 consist of three contaminants, while in the CA method 4 large clusters were formed in the research area of location.

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