Analisis Termodinamika dan Kinetika Nanopartikel Karbon (C-Dot) dari Buah Durian Sebagai Inhibitor Korosi Tembaga

Corrosion is a physical interaction between the metal and its environment, which results in changes in the metal's properties due to chemical or electrochemical reactions. The corrosion rate can be reduced by adding a corrosion inhibitor. Uses of nanotechnology for corrosion prevention is one of the first technical because almost made structures rely on the stability of a 1–2 nm thick passive film which provides stability to the underlying material. Herein we report the thermodynamic and kinetic analysis of carbon-dots from Durian as inhibitor copper corrosion. To test the anticorrosive performance and analyze thermodynamic properties in its role as a corrosion inhibitor on copper using potentiodynamic polarization. The thermodynamic-kinetic parameters of corrosion obtained values of H‡ = 60.44 kJmol-1, ΔS‡ = -73.9 kJmol-1, and ΔG‡ = 82.83 kJmol-1, show that the attendance of C-dot as a corrosion inhibitor causes a non-spontaneous reaction rate to be proven by increasing spontaneity (ΔG‡). The value of activation energy samples was higher than the blank, indicates the presence of C-dot effective to reduce the rate of corrosion of the metal.

Skrining Fitokimia dan Uji Aktivitas Antibakteri Fraksi Etil Asetat dan n-Heksana dari Daun Mangga Kasturi (Mangifera casturi Kosterm.)

Kasturi mango (Mangifera casturi Kosterm.) is a typical mango of South Kalimantan. Kasturi mango leaves are reported to have antioxidant activity and are potential for treating various diseases, including diseases related to antibacterial. This study examines the antibacterial activity of ethyl acetate fraction and the n-hexane fraction of mango musk leaves on bacteria that cause acne. Experimental research started with plant determination, making extracts and fractions, phytochemical screening, and antibacterial testing against Staphylococcus aureus and Propionibacterium acnes using the disk diffusion method. The study results found that the ethyl acetate and n-hexane fractions had weak antibacterial activity against S. aureus and P. acnes bacteria, which cause acne

Analisis Fitokimia Air Rebusan Daun Mantalalu (Euphorbia hirta L) Asal Kota Palu Provinsi Sulawesi Tengah

One of the herbal plants that have long been used as traditional herbal medicine by Central Sulawesi peoples is Mantalalu (Euphorbia hirta L). Central Sulawesi peoples used this Mantalalu to appendicitis medicine. The chemical compound contained in Mantalalu plant has a role in providing different pharmacology. A study was conducted about the chemical compound content Mantalalu plant (Euphorbia hirta L). The method of this research was boiling dried leave and wet leave of Mantalalu plant and phytochemical test including flavonoids tests, alkaloids tests, saponins tests, polyphenol, and tannin tests. The results of this research showed that the decoction of dried and wet leaf samples of Mantalalu plant contained flavonoid, polyphenol, tannin, and saponins bioactive compounds.

Kajian Kadar Akrilamida dalam Kopi Arabika dengan Variasi Suhu Penyangraian

Acrylamide levels in Arabica coffee at various roasting temperatures have been determined. Coffee beans are roasted at 160°C, 180°C, and 210°C for 8 minutes. Analysis was carried out using High-Performance Liquid Chromatography (HPLC) with C-18 reversed-phase, mobile phase using methanol and 0.1% phosphoric acid solution (5:95), flow rate 1 mL/min, UV-Vis detector 198 nm wavelength. Acrylamide levels in Arabica coffee are 160°C of 14.665 ppm, 180°C of 15.973 ppm, and 210°C of 18.501 ppm. Based on the results of the acrylamide content in Arabica coffee, the higher the roasting temperature, the greater the acrylamide content. ANOVA test regarding the normality test sig value of 0.637, 0.463, and 0.637 normally distributed. Based on the homogeneity test, it was found that the variation between groups was the same or homogeneous. The results of the ANOVA test stated that there were differences in the acrylamide levels of Arabica coffee in the roasting temperature difference group and the results of the post hoc Bonferroni test found that the average differences in the roasting temperature of Arabica coffee were significantly different 160°C-180°C and 160°C-210°C.

The The Effect of Concentration of Citric Acid Solution on Extraction of Pectin from Watermelon Albedo

Watermelon albedo or the white flesh of watermelon rind contains pectin with high enough content. In this study was conducted the extraction of pectin from watermelon albedo by the liquid-solid extraction method. The citric acid solution was used as a solvent with concentrations varied by 4%, 7%, and 10%. The research steps include the pretreatment of raw material, the extraction, the posttreatment of extraction, and the analysis of pectin. The pretreatment aimed to reduce water content and reduce the size of raw material. The extraction process was the main process in which pectin dissolution occurred in the citric acid solvent. Furthermore, the posttreatment of extraction aimed to obtain pectin solid with the addition of ethanol. The final step was the analysis, including pectin yield, moisture content, methoxyl content, galacturonic acid content, and pectin functional group. Based on research obtained, an increase in the concentration of citric acid increased pectin yield, methoxyl content, and galacturonic acid content. The moisture content of pectin decreased with the increasing concentration of citric acid. Pectin yield, moisture content, methoxyl content, galacturonic acid content resulted from 10% concentration of citric acid solvent are 8.356%, 19.748%, 7.029%, and 69.048%, respectively. Based on FTIR analysis, the functional groups contained in pectin are hydroxyl group, methyl group, carbonyl group, and ether group. This functional groups are main constituents of pectin structure.

Pengaruh Waktu Hidrotermal terhadap Karakteristik Zeolite Socony Mobile-5 (ZSM-5) Tanpa Template Menggunakan Reaktor Autoclave

ZSM-5 is a synthetic zeolite which has a complex production process and is affected by operating conditions, such as temperature and time. In this study, synthesized ZSM-5 without template by hydrothermal method. An autoclave reactor was used for the hydrothermal process. The aim of this study was to investigate the effect of varied hydrothermal times of 24 and 48 hours with a hydrothermal temperature of 180oC on the characteristic of ZSM-5. The raw materials used were silica oxide and aluminum hydroxide as a source of silica and alumina. The synthesis results were characterized using X-Ray Diffraction (XRD). Based on XRD results, the best result was obtained in performed at 48 hours hydrothermal time indicating the formation of ZSM-5 material at the 22.2o position. The percentage crystallinity of the sample at the hydrothermal time of 48 hours was 51.3%.

Analisis Metabolit Sekunder dan Aktivitas Ekstrak Etanol Kulit Buah Salak (Salacca zalacca (Gaertn.) Voss) Terhadap Kadar Glukosa dan Ureum Kreatinin Tikus Putih Jantan (Rattus norvegicus)

The snake fruit peel (Salacca zalacca (Gaertn.) Voss) traditionally has several health benefits, one of which is to treat diabetes mellitus. This study aimed to determine the content of secondary metabolites in the ethanolic extract of snake fruit peel and its activity on glucose and urea creatinine levels in male white rats (Rattus norvegicus). Phytochemical screening of extracts was carried out qualitatively and quantitatively using UV-Vis Spectrophotometry. This study is a laboratory experimental study using 30 test animals divided into 6 treatment groups (normal control, negative control, positive control, 70 mg/kg BW, 140 mg/kg BW, and 280 mg/kg BW). The results showed that the ethanol extract of the bark of the salak fruit contained 7.61 %w/w alkaloids, flavonoids 0.041% w/w, tannins 1.18% w/w, and saponins 2% w/w. Ethanol extract of salak fruit peel dose of 140 mg/kg BW affected decreasing blood glucose and urea creatinine levels. The skin of the salak fruit has the potential to be further investigated as an antidiabetic.

Hidrolisis Protein Teripang Hitam (Holothuria edulis) Menggunakan Bromelin Kasar dari Batang Nanas (Ananas comocus L)

Black sea cucumber is one type of sea cucumber whose protein content is quite high at 74-82%, not yet widely used by the community as a source of protein. One way to use it is to process the protein into a protein hydrolyzate using the bromelain enzyme which was isolated from pineapple stems. This study aims to determine the concentration of the bromelain enzyme extract and the optimum hydrolysis time to the value of the hydrolysis degree of the hydrolyzate of black sea cucumber protein. Protein hydrolysates are produced by variations of the crude bromelain concentration of 9%, 10%, 11%, and 12% (v/v) and hydrolysis time of 120, 180, 240, and 300 minutes. The results showed that the optimum degree of hydrolysis was obtained with the use of bromelain extract with a concentration of 12% with a value of 11.43% and a hydrolysis time of 240 minutes with a value of 19.17%.

Pembuatan Konsentrat Protein Ampas Kelapa (Cocos nucifera L.) Bebas Lemak pada Berbagai Konsentrasi NaOH

Coconut pulp contains up to 18.2% protein which is one of the wastes from coconut oil processing. Protein from coconut pulp can be used in the manufacture of protein concentrates which are widely used in the food industry. The purpose of this research is to determine the concentration of NaOH that can produce the yield and protein content of coconut pulp protein concentrate. Coconut pulp protein was extracted with NaOH at various concentrations of 0.5, 1, 1.5, 2, and 2.5 M, then continued with salting out using salt (NH4)2SO4 with a saturation of 65%. The crude protein content of coconut pulp protein concentrate was determined by the Kjeldahl method. The results showed that the use of 0.5 M NaOH resulted in the highest protein content of coconut pulp protein concentrate, which was 71.30% with a yield of 14.42%.

Limbah Sabut Kelapa Muda (Cocos nucifera L.) sebagai Sumber Pewarna Kain

Young coconut coir (Cocos nucifera Linn.) waste has the potential to be processed into a useful product, namely as a source of natural dyes, especially in cotton fabrics. Processing is carried out through a maceration process for 72 hours using 96% ethanol as solvent. The obtained extract was applied on cotton cloth with various concentrations of the extract solution, 5, 10, 15, 20, and 25%, and various soaking times of the fabric in the extract for 60, 90, 120, 150, and 180 minutes. The extract was analyzed using Uv-Vis Spekctrofotometer it showed that the ethanol extract or dye that is absorbed into the cotton fabric with various concentrations is 3.43, 4.82, 6.61, 7.79, and 9.03%, respectively. The various soaking times show that on the other hand that the extract absorbed into the fabric was successfully obtained around 7.75, 9.64, 10.81, 11.65, and 12.04%. The results show that the concentration of the extract solution and the increasing length of soaking time can increase the percentage of extract or dye absorbed in cotton fabrics