Lipase catalyzed synthesis of cinnamyl acetate via transesterification in non-aqueous medium

Cinnamyl acetate is used as flavor and fragrance ingredient in food and cosmetic industries. This work focuses on the synthesis of cinnamyl acetate via lipase catalyzed transesterification of cinnamyl alcohol with vinyl acetate in non-aqueous medium. Among the different immobilized lipases employed, Novozym 435 was found to be the best catalyst in toluene as solvent. The effects of various parameters were studied systematically. With a mole ratio of 1:2 of cinnamyl alcohol to vinyl acetate and 10 mg catalyst, 96% conversion was obtained in 1 h at 40 °C. The ternary complex mechanism with inhibition by cinnamyl alcohol was found to fit the data well. The kinetics of the reaction was studied by using non-linear regression analysis. Enzymatic synthesis of cinnamyl acetate is an efficient process vis-à-vis chemical catalysis.     

Constraints on energy intake in fish: the link between diet composition, energy metabolism, and energy intake in rainbow trout

The hypothesis was tested that fish fed to satiation with iso-energetic diets differing in macronutrient composition will have different digestible energy intakes (DEI) but similar total heat production. Four iso-energetic diets (2 × 2 factorial design) were formulated having a contrast in i) the ratio of protein to energy (P/E): high (H(P/E)) vs. low (L(P/E)) and ii) the type of non-protein energy (NPE) source: fat vs. carbohydrate which were iso-energetically exchanged. Triplicate groups (35 fish/tank) of rainbow trout were hand-fed each diet twice daily to satiation for 6 weeks under non-limiting water oxygen conditions. Feed intake (FI), DEI (kJ kg(-0.8) d(-1)) and growth (g kg(-0.8) d(-1)) of trout were affected by the interaction between P/E ratio and NPE source of the diet (P<0.05). Regardless of dietary P/E ratio, the inclusion of carbohydrate compared to fat as main NPE source reduced DEI and growth of trout by ~20%. The diet-induced differences in FI and DEI show that trout did not compensate for the dietary differences in digestible energy or digestible protein contents. Further, changes in body fat store and plasma glucose did not seem to exert a homeostatic feedback control on DEI. Independent of the diet composition, heat production of trout did not differ (P>0.05). Our data suggest that the control of DEI in trout might be a function of heat production, which in turn might reflect a physiological limit related with oxidative metabolism.     

Design, synthesis and structure-activity-relationship of 1,5-tetrahydronaphthyridines as CETP inhibitors

This Letter describes the discovery and SAR optimization of 1,5-tetrahydronaphthyridines, a new class of potent CETP inhibitors. The effort led to the identification of 21b and 21d with in vitro human plasma CETP inhibitory activity in the nanomolar range (IC(50)=23 and 22nM, respectively). Both 21b and 21d exhibited robust HDL-c increase in hCETP/hApoA1 dual heterozygous mice model.     

Jacalin Bound Plasma O-Glycoproteome and Reduced Sialylation of Alpha 2-HS Glycoprotein (A2HSG) in Rheumatoid Arthritis Patients

Glycosylation studies of plasma proteins can reveal information about the onset and progression of diseases, where in the glycan biosynthetic pathways are disturbed as in rheumatoid arthritis (RA). The present study was focused on analysis of O-linked glycoproteins of plasma in RA patients. Two dimensional gel electrophoresis of jacalin bound plasma of RA patients revealed a number of differentially expressed protein spots as compared to healthy controls. Eighteen protein spots were found to have statistically significant (p<0.05) difference in their expression level from four sets of gels and were identified by MALDI-TOF MS. Most of the identified proteins were predicted to be O-glycosylated proteins by Net–O-Gly 3.1 algorithm. Among these the alpha 2HS glycoprotein (A2HSG) was found to be down regulated whereas inter alpha trypsin inhibitor H4 (ITIH4) was up regulated and this was validated by Western blotting. The glycosylation studies showed the reduced N-linked sialylation of A2HSG in RA patients. Altered glycoprotein expression and functional as well as structural studies of glycans might help in the diagnosis of RA and understanding the disease pathogenesis.     

Crystal structure of human seminal diferric lactoferrin at 3.4 Angstrom resolution

Lactoferrin was purified from human seminal fluid obtained from the semen bank. The purified samples were saturated with Fe3+ and crystallized by microdialysis method. The crystals belong to orthorhombic space group P21212, with a = 55.9 Angstrom. b = 97.2 Angstrom, c = 156.1 Angstrom and Z = 4. The structure was determined with molecular replacement method and refined to an R factor of 18.7% for all the data to 3.4 Angstrom resolution. The overall structure of seminal lactoferrin is similar to human colostrum lactoferrin. The amino acid sequence of seminal lactoferrin shows that it has one amino acid less than human colostrum lactoferrin and the structure of its N-terminal region is far more ordered than other lactoferrins. The structure of the iron-binding site and its immediate surroundings indicate well defined features.     

Molecular cloning,structure and bait region splice variants of alpha2-macroglobulin from the soft tick Ornithodoros moubata

The sequence of a alpha(2)-macroglobulin (alpha(2)M) from the soft tick Ornithodoros moubata (TAM) was determined by cloning and sequencing of overlapping polymerase chain reaction (PCR) and rapid amplification of cDNA ends PCR products. The TAM cDNA sequence is 4,944 bp long and contains one open reading frame coding for a protein precursor composed of 1,494 amino-acid residues, including a 24-residue signal sequence. The mature protein is cleaved into two subunits similarly to the C3 and C4 components of complement and fish alpha(2)Ms. Phylogeny analysis revealed that TAM is closely related to Limulus alpha(2)M and displays the highest similarity to the partial sequence of alpha(2)M from hard tick Ixodes scapularis. The comparison of conserved cysteine residues between TAM and human and Limulus alpha(2)Ms made it possible to predict the pattern of disulfide bridges and explain the atypical molecular arrangement of TAM. Four variants of the TAM bait region differing only in a short central segment were found; our data indicate that TAM exists as a single-copy gene in the tick genome and its bait region variants likely arise by alternative splicing. TAM is produced by tick hemocytes and it is also significantly expressed in salivary glands. TAM mRNA levels were shown to be up-regulated upon blood meal.     

Acetaminophen and aspirin inhibit superoxide anion generation and lipid peroxidation, and protect against 1-methyl-4-phenyl pyridinium-induced dopaminergic neurotoxicity in rats

We assessed the antioxidant activity of non-narcotic analgesics, acetaminophen and aspirin in rat brain homogenates and neuroprotective effects in vivo in rats intranigrally treated with 1-methyl-4-phenyl pyridinium (MPP+). Both drugs inhibited cyanide-induced superoxide anion generation, as well as lipid peroxidation in rat brain homogenates, the combination of the agents resulting in a potentiation of this effect. Acetaminophen or aspirin when administered alone or in combination, did not alter dopamine (DA) levels in the forebrain or in the striatum. Intranigral infusion of MPP+ in rats caused severe depletion of striatal DA levels in the ipsilateral striatum in rats by the third day. Systemic post-treatment of acetaminophen afforded partial protection, whereas similar treatment of aspirin resulted in complete blockade of MPP+-induced striatal DA depletion. While these findings suggest usefulness of non-narcotic analgesics in neuroprotective therapy in neurodegenerative diseases, aspirin appears to be a potential candidate in prophylactic as well as in adjuvant therapy in Parkinson's disease.     

A critical evaluation of sample extraction techniques for enhanced proteomic analysis of recalcitrant plant tissues

Most published proteomics studies of bulk plant tissues use a procedure in which proteins are precipitated with trichloroacetic acid (TCA) and acetone (TCA-A), but few attempts have been made to contrast this approach in a systematic way with alternative methods against a spectrum of tissues. To address this, TCA-A was compared with another acetone-based protocol (TCA-B) or a phenol (Phe)-based method, targeting a range of tomato tissues and three species of fruits that contain high levels of contaminating compounds: banana, avocado and orange. The Phe method gave a higher protein yield and typically greater resolution and spot intensity, particularly with extracts from tissues containing high levels of soluble polysaccharides. The methods also generated remarkably different two-dimensional gel electrophoresis (2-DE) protein spot patterns. Peptide mass fingerprinting was used to identify polypeptides that were common to multiple extracts or uniquely present in one extract type. While no clear pattern emerged to explain the basis for the differential protein extraction, it was noted that the Phe method showed enhanced extraction of glycoproteins. These results suggest that the Phe protocol is highly effective with more recalcitrant tissues and that a combination of TCA-A and Phe methods provides enhanced 2-DE based proteomic analyses of most plant tissues.     

Toxicity of Nerium indicum Miller seed extract on bandicoot rat, Bandicota bengalensis Gray

Crude extract (12.5 ml/kg) of N. indicum seed gave 100% mortality of B. bengalensis. Humanness assessment study revealed that this plant orgin chemical caused low pain and sufferings to the target pests.