Optimation of Combination of N-Hexane Solution and Ethyle Acetate on Secondary Metabolite Compounds Profile of Streptomyces hygroscopicus

<p>Streptomyces hygroscopicus (S.hygroscopicus) is a Gram-positive soil bacterium that can produce secondary metabolites from fermentation that have a therapeutic effect. The fermented S. hygrocospicus metabolites that are still in the form of crude extracts are difficult to develop as drug preparations because the active compounds are not yet known, so it will be challenging to determine the dosage of drugs that have a therapeutic effect. Therefore, it is necessary to carry out exploratory research to narrow down the secondary metabolite profile from the fermentation of S. hygroscopicus, using extraction and fractionation methods, which are then identified by Thin-Layer Chromatography (TLC) using a combination of solvents. This study used the extraction method with a separating funnel. The fractionation was carried out using the BUCHI (Sepacore®) Flash Chromatography and Reveleris® PREP Purification System column chromatography gradually using ethyl acetate and n-hexana. 47 and 60 of the fractionation results were taken as samples, that further were profiled using TLC and given the appearance of 10% KOH stains and p-Anisaldehyde - sulfuric acid, so that various classes of compounds with different Rf values were obtained, namely Monoterpenes, Triterpenes, Steroids, Saponins, Coumarin, Scopoletin, and Alkaloids.</p>

Размерный эффект при фазовом равновесии жидкость-жидкость в трехкомпонентной системе

The size effects during phase transformations in systems of submicro- and manometer sizes are expressed in significant changes in phase equilibria. Examples of ternary phase diagrams small volume systems in the literature are virtually absent. The size effect is demonstrated by creating a series of phase diagrams of an aniline-methylcyclopentane-hexane solution. The liquid-liquid phase equilibrium was simulated by the methods of chemical thermodynamics for particles (droplets) with a core-shell configuration with a radius of 100 and 50 nm at temperatures of 25 and 45^oC. Reducing the volume of this system is accompanied by a change in the heterogeneous region, the appearance of metastable states that are absent in the macrophase, and increase the thermodynamic stability of the homogeneous solution.

Modifying the Metal Oxide Filler with a Silicon-Organic Oligomer in a Solution of an Organic Solvent

The use of tungsten dioxide as a filler for a non-polar polymer matrix is limited due to its high hydrophilicity and abrasiveness, which degrades the properties of the filled polymers. The paper presents the results of studies on the surface modification of tungsten oxide with organosilicon polyethylsiloxane. The mechanisms for modifying the surface of tungsten dioxide, based on the fixation of the modifier under the action of intermolecular forces of attraction and interaction of the hydroxyl groups of the oxide surface with the reactive bonds of the Si-H oligomer, have been established. To create additional active centers in the form of groups (–OH) on the surface of tungsten dioxide, it was boiled, which contributes to the forced hydroxylation of the surface. The adsorption of polyethylsiloxane with powdered tungsten dioxide from n-hexane solution was investigated. The results on determination of the wetting angle of unmodified and modified tungsten dioxide powder are presented. It has been established that modification with polyethylsiloxane leads to an increase in the wetting angle of tungsten dioxide to 121o, which indicates its hydrophobic properties.

Biodiesel Production through Catalytic Microwave In-situ Transesterification of Micro-algae (Chlorella sp.)

Aim of this research are to study and develop research related to the potential of Chlorella sp. into biodiesel with the help of microwaves in-situ transesterification by characterizing parameters such as microwave power (300; 450; 600 W) and reaction time (10; 30; 50 minutes) with catalyst concentration of KOH and molar ratio of microalga : methanol are 2% and 1:12 respectively and optimized by response surface methodology with Face Centered Central Composite Design (FCCCD). The study was carried out by dissolving the catalyst into methanol according to the variable which was then put into a reactor containing microalgae powder in the microwave and turned on according to the predetermined variable. After the reaction process is complete, the mixture is filtered and resuspended with methanol for 10 minutes to remove the remaining FAME and then the obtained filtrate is cooled. Water is added to the filtrate solution to facilitate the separation of hydrophilic components before being separated and pushed apart until 3 layers are formed. Amount of FAMEs in the first layer formed were extracted with n-hexane solution and washed with water and the FAME product obtained was then distilled to remove the remaining n hexane and then weighed. The results indicated that yield increased with increasing reaction time and microwave power with the best conditions of 50 minutes each and 440.53 watts with the highest yield reaching 35.72% (dry basis) through using of KOH catalysts with low concentrations, 2%.©2020. CBIORE-IJRED. All rights reserved

Organically Modified Nanoclay Filled Thin-Film Nanocomposite Membranes for Reverse Osmosis Application

This study validates, for the first time, the effectiveness of two nanoclays, that is, cloisite (CS)-15A and montmorillonite (MNT) at the polyamide (PA) active layer in the reverse osmosis (RO) membrane. Cloisite-15A is natural montmorillonite modified with dimethyl dihydrogenated tallow quaternary ammonium salt. Thin-film composite (TFC) membranes were fabricated by the interfacial polymerization (IP) process between the trimesoylchloride (TMC)–n-hexane solution and m-phenylenediamine (MPD)–aqueous solution; the IP process took place on a polysulfone support sheet. The two types of nanoparticles were added in various weight ratios (0.005 wt.%–0.04 wt.%) in the n-hexane solution of TMC. Different characterizations like X-ray diffraction (XRD), contact angle, transmission electron microscopy (TEM), and membrane performance tests were performed to analyse the membrane properties. Both XRD and TEM studies proved that the two nanoclays are successfully anchored at the different sites of the PA layer. CS-15A could accelerate the water flux from 15 to 18.65 L/m2·h with NaCl rejection enhancement from 72% to 80%, relative to the control membrane. Conversely, MNT also enhanced the flux from 15 to 40 L/m2·h, but NaCl rejection reduced from 70% to 23%. The mechanism of water uptake in nanoclays was also discussed. The results pave the way for a complete future study, in which these phenomena should be studied in great detail.

The Effect of Solvent Polarity on Phase Transformation of Citrogypsum via Hydrothermal Process

Calcium sulfate dihydrate (CaSO4•2H2O, CSD), gypsum is a by-product in the production of citric acid (citryogypsum). This by-product could neither be exploited nor distributed as a reactant because of its physical properties including those that are not equivalent to natural gypsum. Moreover, the mentioned citrogypsum has been continually increasing environmental problems. Therefore, this research aims at how to recycle gypsum that is synthesized by hydrothermal method at 95oC for 7 hrs under the atmospheric pressure via different solutions (MeOH, EtOH, PrOH, BuOH and Hexane). In order to produce alpha-calcium sulfate hemihydrate (α-CaSO4•0.5H2O, α-CSH) with improved physical properties that will be used for different industries. FT-IR reveals the chemical composition of crystal and the adsorption of methyl group on the surface. Besides, TGA thermogram shows the theoretical crystal water content of CSD and α-CSH 20.9 wt% and 6.2 wt% respectively. The DSC thermogram, shows that endothermic peaks at 151.2 oC and 168.5 oC. There were two steps of loss at 1.5 and 0.5 water molecule respectively. With SEM images of crystal shows the plate-like shape of citrogypsum, while α-CSH shows the hexagonal shape excluding hexane solution. Of all the results, the polarity of solution has an impact on the transition of CSD to α-CSH under this condition.