Applied chemistry

Chiral Smectic Liquid Crystal (S)-(+)-4-(2-methyl-1-butyloyloxy)phenyl 4-[1-(propenoyloxy) butiloxy] benzoate has been synthesized using method of steglich esterification at room temperature. The mesomorphic behavior of chiral smectic at 55 o C that showed schlieren texture in POM analysis. Fixation of structure chiral smectic liquid crystal by means of photopolymerization of monomer (S)-(+)-4-(2-methyl-1-butyloyloxy)phenyl 4-[1-(propenoyloxy) butiloxy] benzoate under UV irradiation which called UV curing techniques. The curing process using UV 3 lamps 100 volt at 60 0 C for an hour. The product of photopolymerization could be seen by analysis of FTIR spectra both monomer and polymer. FTIR spectra of monomer, two peaks for ester carbonyl and C-C double bond groups appeared at 1729.09 cm -1 and 3123.46 cm -1 . After UV curing process, peak for the carbonyl group at 1729.09 cm -1 decreased and a new peak at 1160.21 cm -1 appeared due to the carbonyl group attached to a C-C bond group and then peak at 3123.46 cm -1 for C-C double bond group was disappeared.

Blending cholesteryl acrylate with methyl phenyl benzoyl acrylate was made by casting solution. Photopolymerization of blending product has been done by varying the UV radiation time were 60, 90, 120 and 150 min using UV curing technique. Curing process doing at temperature range of 55-60 °C. Molecular weight (Mw) of polymers was determined using gel permeation chromatography (GPC) showed the first peak at Mw 2243 and the second peak at Mw 1160 and the result of index polydisperity was 1.02-1.03. Polymer of liquid crystal acrylate from this study was characterisized by XRD, SEM-EDX and FTIR. The XRD pattern peaks appear at 60, 90 and 120 min. SEM image shows the crosslink bonds are formed. EDX graph shows the polymer mixture containing carbon and oxygen. The FTIR spectrum raises wavenumber 1612.56 cm-1 indicates that the C=C bonds contained in the polymer structure. Based on the result of characterization of polymer liquid crystal acrylate with XRD, SEM-EDX and FTIR shown that best product was from radiation time polymerization at 90 min.

Ramie fiber is a potential raw material to substitute imported raw materials such as cotton. Due to its higher hemicellulose content, ramie fiber required hydrolysis in a process called degumming. Enzymatic degumming is environmentally friendly compared to traditional process which using chemicals. Alkalithermophilic xylanase have high ability in hemicellulose hydrolysis. The production of xylanase was conducted by submerged fermentation of Bacillus halodurans CM1 in 20L bioreactor using Mamo and corncob medium with optimum conditions at 50°C, pH 9, 150 RPM and 1 vvm. The optimum specific activity of xylanase measured by Bailey method at 70°C and pH 9 is 475.41 U/mg. Xylanase was stable at 50°C, pH 9 and relatively stable to K+, Na2+, Co2+ and Ca2+ metal ions and Triton-X, Saba dan Tween-80 surfactants. Degumming process was carried out by immersing ramie fibers in formulated degumming solution with vlot 1:20 at 50°C, 150 RPM and 180 minutes. The enzymatic degumming process may subs...

SYNTHESIS AND STRUCTURE CHARACTERIZATION OF ESTER BENZOATE TYPE OF FERROELECTRIC LIQUID CRYSTAL DERIVED FROM (S)-(+)-2-METHYLBUTANOIC ACID. Synthesis method of ester benzoate type of ferroelectric liquid crystal derived from (S)-(+)-2-methylbutanoic acid, was developed via esterification between (S)-(+)-p-hydroxyphenyl-2-methylbutanoate ((S)-(2-HFM)) and acryloyloxy butyloxy benzoic acid (ABB). The chiral alcohol compound of (S)-(+)-2-HFM was obtained by Steglich selective-esterification of hydroquinone with dicyclohexylcarbodiimide (DCC) and dimethylaminopyridine (DMAP) as catalists. While acrylate compound of ABB was obtained by a serie of synthesis processes of 4-chlorobuthyl acetic acid as a main compund. The serie of processes started from a formation of Williamson ether, and then followed by a base hydrolisis, and finally ended by an acrylation process. Structure characterization of the obtained ferroelectric liquid crystal was carried out by Fourier Transform Infra Red (FT-IR...

Scaffold is a 3-dimensional matrix created as a new bone cell growth medium made from natural polymers and bioceramics. The extracted pectin from green Cincau leaves (Premna oblongifolia Merr) and hydroxyapatite (HA) are used in the manufacture of scaffolds. Pectin was extracted using citric acid with variation concentration of 0, 0.1, 0.2 and 0.3% (w / v). The 3% (w / w) HA-pectin mixture, dried freeze using a freeze dryer. The characterization of extracted pectin and HA-pectin scaffold was then performed. The results showed that pectin of green Cincau leaves had low methoxyl content, which was 1.364 to 5.022%. The resulting scaffold has a pore size ranging from 8.25 to 115 µm while the scaffold resistance to the load, ie 0.03 to 0.15 MPa. The scaffold porosity that has been made is 15.33 to 40.97% while the density is 0.69 to 1.02 g/cm3.

Sunaryanto et al, 2019. Optimization of Penicillium lagena Medium Cultivation on Antifungal Pathogen of Phellinus lamaoensis using Response Surface Methodology. pp. 410-420. Phellinus lamaoensis (Murr.) Hein is fungal pathogen that can cause brown root rot disease in cocoa, tea, rubber, and coffee plants. Endophytic fungi, Penicillium lagena, isolated from bandotan (Ageratum conyzoides Linn.), medicinal plant, is able to inhibit the growth of pathogenic, P. lamaoensis. The effect of carbon source, nitrogen source, and mineral solution was studied. Lactose, yeast extract, and mineral solution were media components which showed significant effect toward production of P. lagena active compound. Composition optimization of these three medium components was done by response surface methodology (RSM). The Optimal response region of the significant factor was predicted by using a second order polynomial model with statistical design, central composite design (CCD). Higest production of P. ...