Anticancer effects and lysosomal acidification in A549 cells by Astaxanthin from Haematococcus lacustris

Astaxanthin (AXN) is known to have health benefits by epidemiological studies. Therefore, it is of interest to assess the effect of AXN (derived from indigenous unicellular green alga Haematococcus lacustris) to modulate cell cycle arrest, lysosomal acidification and eventually apoptosis using in vitro in A549 lung cancer cells. Natural extracts of astaxanthin were obtained by standardized methods as reported earlier and characterized by standard HPLC and MS. Treatment of A549 cells with AXN (purified fraction) showed significant reduction in cell viability (about 50%) as compared to crude extract at 50µM concentration. Thus, we show the anticancer effects and lysosomal acidification in A549 cells by Astaxanthin from Haematococcus lacustris for further consideration. Together, our results demonstrated the anticancer potential of AXN from Haematococcus lacustris, which is found to be mediated via its ability to induce cell cycle arrest, lysosomal acidification and apoptotic induction.     

Fragment analogs as better mimics of obestatin

Obestatin is a twenty three amino acid peptide produced in the stomach by post translational modification of the preproghrelin gene. Since its discovery in 2005, many studies have shown that obestatin reduces feed intake and gain in body weight in rodents. Studies from our laboratory have shown the N-terminal thirteen residues mimic obestatin the best and residues 6–18 reduce epididymal fat significantly in adult male mice. In this study we have tried to increase the efficacy of these fragments. As an initial step, we have substituted G(8) with α-aminoisobutyricacid(Aib,U) and F(5) with cyclohexylalanine(Cha) in the N-terminal peptide to obtain two modified peptides and modified the middle fragment (residues 6–18) by substituting both the glycine residues at position 3 and 8 with α-aminoisobutyricacid(U). The rationale being, unusual amino acids could protect the peptides from immediate degradation and Aib would also induce secondary structure in these unstructured peptides. The N-terminal fragment with the G(8)U substitution fared the best. It reduced food intake, gain in body weight, levels of cholesterol and triglycerides in the blood, epididymal and perirenal fat in adult male mice similar to that of obestatin. The middle fragment with G(3,8)U double substitution was the second best.     

Improved biodegradation of Congored by using Bacillus sp

The biodegradation of Congored, a toxic azo dye, was studied by using a hybrid technique involving sonolysis as pretreatment followed by biological treatment. The experiments were carried out with and without pretreatment using dye solution as a sole source of nutrition with an isolated and acclimatized strain of Bacillus sp. obtained from tannery industry effluent. The pretreatment time was varied as 30, 60, 90, 120, 150 and 180 min and then the pretreated dye solution was subjected to biological treatment. The effectiveness of pretreatment was compared with the results of biological degradation of non pretreated Congored and the results showed that the pretreatment improved the efficiency of the biodegradation of Congored. During the biological degradation, the increase in initial dye concentration decreased the decolorization rate and at high concentrations (1500 and 2000 mg/l), the inhibition was observed. The optimum pH and temperature were determined to be 7.0 and 37 degrees C, respectively. The data obtained through biodegradation experiments were fitted with five different kinetic models and the results were analyzed.     

An overview on the recent advances in the transesterification of vegetable oils for biodiesel production using chemical and biocatalysts

Biodiesel, chemically defined as monoalkyl esters of long chain fatty acids, are derived from renewable feed stocks like vegetable oils and animal fats. It is produced by both batch and continuous transesterification processes in which, oil or fat is reacted with a monohydric alcohol in the presence of a catalyst. The conventional method of producing biodiesel involves acid and base catalysts to form fatty acid alkyl esters. Downstream processing costs and environmental problems associated with biodiesel production and byproducts recovery have led to the search for alternative production methods and alternative substrates. Enzymatic reactions involving lipases can be an excellent alternative to produce biodiesel through a process commonly referred to as alcoholysis, a form of transesterification reaction or through an interesterification reaction. In order to increase the cost effectiveness of the process, the enzymes are immobilized using a suitable matrix. The use of immobilized lipases and whole cells may lower the overall cost, while presenting less downstream processing problems. Main focus of this paper is to discuss the important parameters that affect the biodiesel yield, various immobilization techniques employed, mechanisms and kinetics of transesterification reaction and the recent advances in continuous transesterification processes.     

Response surface optimization of mixed substrate solid state fermentation for the production of lovastatin by Monascus purpureus

The objective of this work is to enhance the production of lovastatin using Monascus purpureus MTCC 369 in mixed substrate solid state fermentation using various solid substrates and to optimize the combination of the solid substrates by response surface methodology. Solid state fermentation was conducted in a 250 mL Erlenmeyer flask at 30°C for 14 days with initial moisture content of 40% and inoculum size of 10% active culture. Barley, long grain rice and sago starch were found to be the suitable substrates producing maximum lovastatin of 193.7 mg, 190.2 mg and 180.9 mg/g of dry solids. These substrates were further used in various combinations as designed by the central composite design for enhancing the lovastatin production using Monascus purpureus. To the best of our knowledge this is the first report on the production of lovastatin using a mixed substrate solid state fermentation using Monascus purpureus.     

Root Suberin Forms an Extracellular Barrier That Affects Water Relations and Mineral Nutrition in Arabidopsis

Though central to our understanding of how roots perform their vital function of scavenging water and solutes from the soil, no direct genetic evidence currently exists to support the foundational model that suberin acts to form a chemical barrier limiting the extracellular, or apoplastic, transport of water and solutes in plant roots. Using the newly characterized enhanced suberin1 (esb1) mutant, we established a connection in Arabidopsis thaliana between suberin in the root and both water movement through the plant and solute accumulation in the shoot. Esb1 mutants, characterized by increased root suberin, were found to have reduced day time transpiration rates and increased water-use efficiency during their vegetative growth period. Furthermore, these changes in suberin and water transport were associated with decreases in the accumulation of Ca, Mn, and Zn and increases in the accumulation of Na, S, K, As, Se, and Mo in the shoot. Here, we present direct genetic evidence establishing that suberin in the roots plays a critical role in controlling both water and mineral ion uptake and transport to the leaves. The changes observed in the elemental accumulation in leaves are also interpreted as evidence that a significant component of the radial root transport of Ca, Mn, and Zn occurs in the apoplast.     

Conformational preferences of 1,4,7-trithiacyclononane: a molecular mechanics and density functional theory study

Conformational preferences of 1,4,7-trithiacyclononane were studied using a highly efficient sampling technique based on local nonstochastic deformations and the MM2(91) force field. The results show that conformers that the molecule adopts in the crystal state were found to be low-energy conformers (LECs) within 5 kcal mol(-1) of the global minimum. A conformation with C1 symmetry was the global minimum and the C3 and C2 conformations were calculated to be 0.03 and 1.78 kcal mol(-1) higher in energy, respectively. The structures were further minimized using Density Functional Theory (DFT) calculations with two different functionals. The C2 and the C1 conformations were found to be LECs with the C3 conformation more than 4.0 kcal mol(-1) above the global minimum. The relative energies and structural ordering obtained using the BP86 functional are in agreement with the previously reported relative energies calculated using second-order Moller-Plesset (MP2) ab initio calculations. With the energy ordering being dependent on the molecular mechanics force field used, the approach of MM-->DFT (searching exhaustively the available conformational space at the MM level followed by generating the energy ordering through DFT calculations) appears to be appropriate for thiacrown ethers.