KOVALEN: Jurnal Riset Kimia
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Isolasi dan Pemurnian Protein dari Lembaga Jagung (Corn Germ) Menggunakan Metode Presipitasi dan Dialisis: Protein Isolation and Purification from Corn Germ Using Precipitation and Dialysis Methods
Get PDFThe protein contained in corn germ can be used as a raw material that has the potential to provide many benefits in the food, pharmaceutical, and plastic industries. Corn germ with the highest content of protein is around 12-18.4%. In this study, protein from corn germ was isolated and homogenized using tris buffer HCl at pH 7.2. To obtain the protein fraction, precipitation was carried out (salting-out) using a solution of (NH4)2SO4 with saturation levels of 25%, 50%, and 70% respectively. The purification process was carried out by dialysis for 24 hours. The dialysis produced pure protein with a concentration of 4.161%. Based on the identification of functional groups using an FT-IR spectrophotometer, it was shown that the isolated and purified corn germ protein contained four absorption bands, including amide A (3211.48 cm-1 and 3226.91 cm-1), amide I (1633 cm-1 and 1629.85 cm-1), amide II (1527 cm-1 and 1552.70 cm-1) and amide III (1296.16 cm-1). The four absorption bands correspond to the wavenumbers of corn protein stated in the literature and are estimated to contain albumin, globulin, glutelin, and zein
Penggunaan Karbon Aktif dari Tandan Kosong Kelapa Sawit Teraktivasi NaOH pada Penyerapan Ion Pb(II): Utilization of NaOH-Activated Carbon from Oil Palm Empty Fruit Bunches on Pb(II) Ion Absorption
Get PDFOil palm empty fruit bunches (OPEFB) are plantation waste that has the potential to be used as activated carbon. The main component of OPEFB is lignocellulosic which can be a source of activated carbon and utilized for Pb2+ ion adsorption. The use of activated carbon activated by NaOH still requires optimization, especially in determining the contact time and optimum adsorption pH. This study aims to determine the effect of pH and contact time on the adsorption of Pb2+ and to determine the efficiency of the adsorbent on the adsorption of Pb2+. In this study, activated carbon from OPEFB was carbonized at 300oC for 1 hour, followed by activation using NaOH 0.5%. The results showed that the use of pH 5 and a contact time of 90 minutes had a relatively higher Pb2+ adsorption than other conditions. However, the use of variations in pH and contact time had no significant effect on the adsorption of Pb2+ ions. Adsorbents with variations in pH 4, 5, 6, 7, and 8 were able to absorb Pb2+ of 99.73%, 99.86%, 99.74%, 99.79%, and 99.80%, respectively. Adsorbents with variations in contact time of 30, 60, 90, 120, and 150 minutes were able to absorb Pb2+ of 99.28%, 99.40%, 99.48%, 99.44%, and 99.48%, respectively
Pengaruh Konsentrasi Ekstrak Daun Eboni dan Daun Sirsak Terhadap Retensi Bahan Pengawet pada Kayu Durian (Durio zibethinus): The Effect of Concentration of Ebony and Soursop Leaves Extracts on Retention of Preservatives in Durian Wood
Get PDFDurian wood is one type of wood that has a low level of durability, therefore it is necessary to make efforts to increase the durability of wood. These efforts can be done by preserving the durian wood by using natural preservatives, namely ebony leaves extract and soursop leaves. Ebony and soursop leaves extracts were used as natural preservatives with different concentrations using the cold soak method on durian wood. The research conducted aims to determine the effect of extract concentration on the retention of preservatives. Ebony leaves and soursop leaves were extracted by maceration method in 96% ethanol solvent for 24 hours. The durian wood sample was preserved using the cold soaking method for 1 hour using ebony leaves extract and soursop leaves extract at concentrations of 1%, 2%, and 3%. The results showed that the highest retention of preservatives from ebony leaves extract and soursop leaves extract was the use of 3% concentrations of 0.661 kg/m³ and 0.676 kg/m³, respectively. The results of the analysis of variance showed that the extract concentration had a significant effect on the retention value. The concentration of preservatives from ebony leaves extract and soursop leaves is directly proportional to the retention value of preservatives. Preservative retention of soursop leaves extract is better than ebony leaves extract
Sintesis dan Karakterisasi Feâ‚‚TiOâ‚… dari Besi Oksida dan Titanium Dioksida dengan Metode Planetary Ball-Mill: Synthesis and Characterization of Feâ‚‚TiOâ‚… from Iron Oxide and Titanium Dioxide Using the Planetary Ball-Mill Method
Get PDFThe method of solid hydrogen storage through integration in metal hydride compounds is a new, promising method. This research has succeeded in synthesizing and characterizing the metal hydride alloy Fe-Ti system through a planetary ball-mill process. Based on the XRF analysis, it was found that the composition of Fe oxide content reached 56.22% while Ti oxide reached 43.78%. The FTIR study showed absorption at wavenumbers of 900 cm-1 and 500 cm-1. Both are typical absorptions for Ti-O and Fe-O groups, suggesting that the synthesized sample was successful. It can be seen from the XRD data that some of the diffractogram peaks of the resulting Fe-Ti compound match the peaks of the Fe2TiO5 and TiO2 compounds obtained from the Powder Diffraction File (PDF) database number 00-003-0374. After the refinement was performed, information was obtained that the synthesis of Fe-Ti alloy material using the planetary ball mill technique produced Fe2TiO5
Synthesis and Performance Evaluation of Cellulose-based Slow-release Fertilizer: A Review
Get PDFCellulose-based materials are attractive candidates for the fabrication of sustainable and eco-friendly slow-release fertilizers. The ability of the cellulose structure to be modified and functionalized makes it promising as a scaffold backbone in the development of advanced agricultural materials. In this review, different synthesis techniques of cellulose-based slow-release fertilizers are discussed. Crucial parameters in the design of the slow-release fertilizers (i.e., slow-release behavior, water retention properties, and biodegradability) are presented. The applications of cellulose-based fertilizers in enhancing the growth of agricultural and horticultural commodities are provided. To date, solution polymerization is more widely employed in the preparation of cellulose-based slow-release fertilizers due to its low cost and simple operation, with no solvent recovery required. Esterification tends to be the most typical reaction during the synthesis of the fertilizers because of its high substrate solubility and more straightforward product purification. This review can be used as a reference to develop other efficient cellulose-based slow-release fertilizers that can be utilized to delay the release of fertilizers and prevent the overuse of fertilizers
Determination of Mercury (Hg) and Lead (Pb) in Sedimen of Batanghari River in Dharmasraya Regency
Get PDFBatanghari River is a river that crosses the Province of West Sumatra and Jambi Province, which flows through the Dharmasraya Regency area. Along this river, many illegal gold mines are found, which use mercury (Hg) as a gold-binding medium, and fuel oil containing lead (Pb) as fuel for machinery used in mining operations. This mining activity is the cause of the presence of Hg and Pb in the mining environment which is passed by the Batanghari river. The source of Pb is also from tailings, which is the remaining metal ore processing that does not meet the requirements to be taken at the time of mining. the presence of Hg and Pb metals in the aquatic environment will have an impact on the environment and interfere with the health of miners and the surrounding community, because Hg and Pb are heavy metals that are toxic. Research has been carried out on the Batanghari river sediments in January and April 2019 using the Atomic Absorption Spectrophotometer (FAAS) method to measure Pb and the Cold Vapor Atomic Absorption Spectrophotometer (CV AAS) method for Hg metal. The results showed that each metal Hg and Pb, in mg metal per Kg sediment, in the range of 0.08 mg/kg – 10.21 mg/kg, and 1.81 mg/kg – 23.10 mg/kg. Based on these data, it can be said that in January and April 2019 the metal content of Hg and Pb in the Batanghari river air was above the river water quality standard according to the Government Regulation of the Republic of Indonesia, namely 0.001-0.002 mg/L for Hg and 0.03 mg/L for P
Aktivitas Antibakteri Ekstrak Kulit Batang Tumbuhan Johar (Senna siamea Lam) pada Berbagai Polaritas Pelarut : Antibacterial Activity of Johar (Senna siamea Lam) Stem Bark Extract on Various Solvent Polarities
Get PDFJohar plant is a type of plant from the Fabaceae family which is widely used in traditional medicine such as malaria, itching and diabetes medicine. This study aims to determine the antibacterial activity of Johar stem bark extract with different levels of solvent polarity on the growth of Staphylococcus aureus and Escherichia coli bacteria and to determine the active compound class by TLC-Bioautography. The extraction of active compounds used a multilevel maceration method starting with n-hexane (non polar), followed by ethyl acetate (semi-polar) and ethanol (polar) solvents. Antibacterial activity testing was carried out by diffusion well method with a concentration variant of 25% and 50%. The results showed that n-hexane, ethyl acetate, and ethanol extract had antibacterial activity against the two test bacteria. Ethyl acetate and ethanol extract from Johar stem bark at a concentration of 50% were classified as very strong antibacterials with inhibition zone diameters against S. aureus, which were 22.02±0.84 mm and 20.16±0.23 mm, respectively. The results of the TLC-Bioautography test showed that the three test extracts had strong antibacterial activity against S. aureus and E. coli. In the n-hexane extract with n-hexane: ethyl acetate (9:1) eluent using Lieberman-Burchard spray reagent, it was suspected that triterpenoid compounds were present. In ethyl acetate extract with n-hexane: ethyl acetate (6:4) eluent and ethanol extract with chloroform: methanol (8:2) eluent using FeCl3 1% spray reagent, it was suspected that the tannin compound was present in both extracts
Penambatan Molekuler Penghambatan Aktivitas Enzim α-Amilase dan α-Glukosidase oleh Senyawa Aktif Daun Kirinyuh (Chromolaena odorata L.): Molecular Docking for Inhibition of α-Amylase and α-Glucosidase Enzyme Activities by Active Compounds of Kirinyuh Leaves (Chromolaena odorata L.)
Get PDFAn in silico study was conducted to inhibit the active compound in Kirinyuh leaves (Chromolaena odorata L.) against α-amylase and α-glucosidase enzymes using a molecular docking approach. The docking was carried out on 19 active compounds that had been identified in Kirinyuh leaves and were optimized using the PM3 method. The best results in inhibit on of the α-amylase enzyme were shown by compounds from the flavanone group, namely genkwanin and sakuranetin with binding affinities of -8.3 kcal/mol and -8.1 kcal/mol, respectively, while the best results in inhibiting on of the α-glucosidase enzyme were shown by two compounds from the hydroxybenzoic acid group, namely p-coumaric acid and p-hydroxybenzoic acid with bond affinities of -5.7 kcal.mol and -5.5 kcal.mol, respectively. The interaction between α-amylase with genkwanin and sakuranetin produces one conventional hydrogen bond GLU 233 and GLN 63 respectively. The interaction between α-glucosidase with p-coumaric acid and p-hydroxybenzoic acid produces three conventional hydrogen bonds, HIS 112; GLN 182; ASP 352 and GU 277; GLN 279; ASP 352
Arang Aktif Ampas Tebu Termodifikasi Kitosan sebagai Adsorben Tetrasiklin: Pemanfaatan Metode Kolom: Chitosan Modified Sugarcane Bagasse Activated Charcoal as Tetracycline Adsorbent: Utilization of the Column Method
Get PDFCurrently, antibiotics are considered environmental pollutants because of their undesirable effects on human health and the environment, including the waste of antibiotics tetracycline hydrochloride. While on the other hand, bagasse is an agricultural waste that has no economic value. This study aims to study the characteristics of activated charcoal from bagasse and the use of bagasse as chitosan-modified activated charcoal using the column method to determine the variation of adsorbent height, flow rate, and acidity of the solution in the ability of the bagasse adsorbent to adsorb tetracycline hydrochloride. Bagasse goes through a carbonation process using a furnace at a temperature of 350°C until charcoal is formed. The next process is activation using 2 M phosphoric acids and compared based on SNI 06-3730-1995 regarding technically activated charcoal. Determination of functional groups using Fourier Transform Infra-Red, adsorbent morphology using Scanning Electron Microscope, and crystallinity using X-Ray Diffraction. The concentration of tetracycline hydrochloride before and after adsorption was measured using an Ultra Violet-Visible spectrophotometer. The best absorption results in the adsorption process were found at the adsorbent height of 14 cm (99%), the flow rate of 0.5mL/minute (92%), and pH 4 (93%)
Ekstraksi Teh Hijau dan Aplikasinya sebagai Pengendali Korosi Pada Pompa di Lingkungan Garam NaCl 3,56%: Green Tea Extraction and Its Application as Corrosion Controller in 3.56% NaCl
Get PDFGreen tea leaves contain antioxidant compounds that can be used as organic inhibitors in a corrosion process. Tea leaves were extracted by maceration method using 70% ethanol solution with a solid:solvent ratio of 1:8 (w/v) for 1 x 24 hours in an atmospheric room. The extract was then concentrated with a rotary evaporator and separated with solvent under vacuum conditions at 852 mbar, temperature of 70oC and rotation of 80 rpm. The results of the qualitative test of extra tea leaves using 10% NaOH and 1% FeCl3 changed the color to brownish orange and blue-black. This indicates the content of flavonoids and tannins. Green tea leaf extract is also applied to control the corrosion rate of brass metal. Variations in the concentration of tea leaves were 200, 400, 600 ppm in 3.56% NaCl solution. The pump circulation is carried out for 40 hours, the weight loss method is carried out every 8 hours. The average corrosion rate without inhibitor is 3.95 mmpy, the corrosion rate with 200 ppm inhibitor is 1.24 mmpy, the corrosion rate with 400 ppm inhibitor is 0.46 mmpy, the corrosion rate with 600 ppm inhibitor is 0.23 mmpy. A significant decrease in the corrosion rate occurred at a concentration of 600 ppm with an efficiency of 92.32%