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Selective sugarcane bagasse (SCB) fractionation was conducted to produce cellulose-rich material for separate saccharification and fermentation to lactic acid. The highest glucose yield of 87.1% based on the polysaccharides in treated SCB was from a 2-step acid ethanolysis/alkaline peroxide pretreatment. The yield of lactic acid due to fermentation by Lactobacillus casei from SCB hydrolysate in a 3-L bioreactor was about 21.3 g/L after 120 h with the productivity of about 0.63 g/L h. For lactic acid separation, the low flux nanofiltration membrane showed higher performance in comparison with the high flux membrane. Using nanofiltration with low flux membrane, lactic acid was efficiently separated from the fermentation broth with glucose rejection of about 93.28%. The selectivity of the low flux membrane for separation of lactic acid and glucose in fermentation broth at 6 bar was found to be 82.48. [ABSTRACT FROM AUTHOR]

The major clinical hindrance of orthopedic implants is the bacterial infection, which can lead to biofilm formation and ultimately results in implant rejection. In this research, layer-by-layer nanocoating consists of vancomycin/PLA/vancomycin-loaded niosomes was designed. Vancomycin-loaded niosomes were formulated by thin film hydration method and the attributes of niosomes in terms of size, zeta potential, drug loading and EE, were assessed. The size was 340.5 ± 2.95 nm with the zeta potential and %EE was 45.4 ± 0.77 mV and 50.47 ± 3.66% respectively. The dip coating technique was used to deposit a thin film, which was characterized morphologically under FE-SEM. Drug release from coated bone plates with and without vancomycin-loaded niosomes was also studied and results suggested that bone plates coated with vancomycin-loaded niosomes have accumulated more vancomycin than the control group and hence aided in the prolonged release up to two weeks. These niosomes-coated bone plates demonstrated superior antibacterial activity for longer time period, without exhibiting any cytotoxic effects towards normal cells (L929). These findings offer a promising approach to control the bacterial colonization and biofilms formation. This thin film nano-coating can also be utilized in coating of other medical devices, which are prone to infections. [ABSTRACT FROM AUTHOR]

Diblock copolymers of poly(#x03B5;-caprolactone) (PCL) and monomethoxy poly(ethylene glycol) (MPEG) with various compositions were synthesized. The amphiphilic block copolymers self-assembled into nanoscopic micelles and their hydrophobic cores encapsulated doxorubicin (DOX) in aqueous solutions. The micelle diameter increased from 22.9 to 104.9 nm with the increasing PCL block length (2.5–24.7 kDa) in the copolymer composition. Hemolytic studies showed that free DOX caused 11% hemolysis at 200 μg ml-1, while no hemolysis was detected with DOX-loaded micelles at the same drug concentration. An in vitro study at 37 °C demonstrated that DOX-release from micelles at pH 5.0 was much faster than that at pH 7.4. Confocal laser scanning microscopy (CLSM) demonstrated that DOX-loaded micelles accumulated mostly in cytoplasm instead of cell nuclei, in contrast to free DOX. Consistent with the in vitro release and CLSM results, a cytotoxicity study demonstrated that DOX-loaded micelles exhibited time-delayed cytotoxicity in human MCF-7 breast cancer cells. [Copyright &y& Elsevier]

Sugarcane bagasse fractionation and hydrolysis using heterogeneous catalysts in aqueous biphasic system was investigated. Carbon-based, polymer-based and metal-based catalysts were synthesized and tested for hydrolysis of sugarcane bagasse in a combination of solvent-based and polymer-based aqueous biphasic system at different polarities for sugar production. The results showed that acid density, functional groups and physical properties of catalysts influenced the catalytic activity on cellulose hydrolysis. From solvent screening study, nitrobenzene was the most promising solvent enhancing relatively high total reducing sugar (TRS) yield of 97.4% when hydrolysis took place at 140 °C for 4 h in the presence of carbon-based catalyst type 1(C-SO 3 H). Nevertheless in terms of recyclability, magnetic metal-based catalyst (SO 4 2− /TiO 2 /Fe 3 O 4 ) that yielded considerably high amount of glucose at elevated temperature and shorter time (180 °C 1 h) was suitable catalyst as it was easily separated from the solution. Kinetic study of cellulose hydrolysis reaction was performed, in which rate constant and activation energy of reaction catalyzed by active catalysts were compared. The results suggested an effective integrated system for cellulose fractionation and hydrolysis in which lignin-rich fraction was in solvent and polymer phases while cellulose fibers were remained in the aqueous phase and further hydrolyzed by heterogeneous catalyst. [ABSTRACT FROM AUTHOR]

This work describes the preparation and characterization of anticancer-loaded injectable polymeric depots that consisted of d, l-lactide (LA), ε-caprolactone (CL), and poly(ethylene glycol) (PEG) or [poly(ε-caprolactone)-random-poly( d, l-lactide)]-block-poly(ethylene glycol)-block-[poly(ε-caprolactone)-random-poly( d, l-lactide)] (PLEC) copolymers for malignant gliomas treatment. PLECs were polymerized with different percentages of LA to deliver 7-ethyl-10-hydroxycamptothecin (SN-38), a highly potent anticancer drug. SN-38-loaded depots could form directly in phosphate buffer saline with more than 98% encapsulation efficiency. The release rate of SN-38 from depots was found to depend on the amount of LA in PLECs, loading content of SN-38 in the depots, and depot weight. Encapsulation of SN-38 inside depots could enhance the stability of SN-38 where all of SN-38 released after 60 days was in an active form. Depots without SN-38 were evaluated as noncytotoxic against U-87MG, whereas SN-38-loaded depots showed cytotoxic effect as a function of concentration. © 2012 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 101:3708-3717, 2012 [ABSTRACT FROM AUTHOR]