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Percentage Inhibition (percentage + inhibition)
Selected AbstractsEffect of different cooking methods on the antioxidant activity of some vegetables from PakistanINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2008Bushra Sultana Summary The effects of different cooking methods (boiling, frying and microwave cooking) on the antioxidant activity of some selected vegetables (peas, carrot, spinach, cabbage, cauliflower, yellow turnip and white turnip) were assessed by measuring the total phenolic contents (TPC), reducing power and percentage inhibition in linoleic acid system. TPC (gallic acid equivalents g/100 g of dry weight) and reducing power of the methanolic extracts of raw-, microwaved-, boiled- and fried vegetables ranged 0.333,2.97, 0.52,2.68, 0.48,2.08, 1.00,2.02 and 0.391,2.24, 0.822,1.10, 0.547,1.16, 0.910,4.07, respectively. The level of inhibition of peroxidation ranged 71.4,89.0, 66.4,87.3, 73.2,89.2 and 77.4,91.3%, respectively. Antioxidant activity of the vegetables examined was appreciably affected because of varying cooking treatments. TPC of vegetables, generally, decreased by boiling, frying and microwave cooking. There was a significant (P < 0.05) increase in reducing power as a result of frying. However, boiling and microwave cooking did not affect reducing power. Inhibition of peroxidation increased by boiling and frying, whereas, in contrast it was decreased by microwave cooking. The results of the present investigation showed that all the cooking methods affected the antioxidant properties of the vegetables; however, microwave treatment exhibited more deleterious effects when compared with those of other treatments. Thus an appropriate method might be sought for the processing of such vegetables to retain their antioxidant components at maximum level. [source] ORIGINAL ARTICLE: Investigating the inhibitory activity of green coffee and cacao bean extracts on pancreatic lipaseNUTRITION BULLETIN, Issue 3 2010S. Almoosawi Summary The present study investigated the effects of green coffee bean extract and Theobroma cacao bean extract on pancreatic lipase activity in vitro. Green coffee bean extract produced a J-shaped dose-dependent inhibition of pancreatic lipase with the percentage inhibition of pancreatic lipase ranging from 11.8% to 61.5%. Similar concentrations of Theobroma cacao failed to produce any effect on pancreatic lipase. Non-linear regression analysis revealed that the concentration of green coffee bean extract required to elicit a 50% inhibition of pancreatic lipase activity (IC50) was approximately 43 µM. In conclusion, extracts of green coffee beans but not Theobroma cacao possess potent inhibitory activity against pancreatic lipase. [source] In vitro antioxidant studies and free radical reactions of triphala, an ayurvedic formulation and its constituentsPHYTOTHERAPY RESEARCH, Issue 7 2005G. H. Naik Abstract The aqueous extract of the fruits of Emblica officinalis (T1), Terminalia chebula (T2) and Terminalia belerica (T3) and their equiproportional mixture triphala were evaluated for their in vitro antioxidant activity. , -Radiation induced strand break formation in plasmid DNA (pBR322) was effectively inhibited by triphala and its constituents in the concentration range 25,200 µg/mL with a percentage inhibition of T1 (30%,83%), T2 (21%,71%), T3 (8%,58%) and triphala (17%,63%). They also inhibited radiation induced lipid peroxidation in rat liver microsomes effectively with IC50 values less than 15 µg/mL. The extracts were found to possess the ability to scavenge free radicals such as DPPH and superoxide. As the phenolic compounds present in these extracts are mostly responsible for their radical scavenging activity, the total phenolic contents present in these extracts were determined and expressed in terms of gallic acid equivalents and were found to vary from 33% to 44%. These studies revealed that all three constituents of triphala are active and they exhibit slightly different activities under different conditions. T1 shows greater efficiency in lipid peroxidation and plasmid DNA assay, while T2 has greater radical scavenging activity. Thus their mixture, triphala, is expected to be more efficient due to the combined activity of the individual components. Copyright © 2005 John Wiley & Sons, Ltd. [source] Analysis of gene expression in human bronchial epithelial cells upon influenza virus infection and regulation by p38 mitogen-activated protein kinase and c-Jun-N-terminal kinaseRESPIROLOGY, Issue 2 2008Shinichi HAYASHI Background and objective: Airway epithelial cells, which are the initial site of influenza virus (IV) infection, participate in the inflammatory process through the expression of various genes. In this process, mitogen-activated protein kinase (MAPK) may be associated with the expression of many genes, but its precise role remains unknown. Methods: A comprehensive analysis was performed of gene expression in human bronchial epithelial cells upon IV infection, using an Affymetrix gene chip containing 12 000 genes. Regulation of gene expression by MAPK was also analysed. Results: A total of 5998 genes were detected. Upon IV infection, 165 genes were upregulated and 49 of these were interferon-stimulated genes. The functions of 129 genes, including 14 apoptosis-related genes and 6 antiviral genes, were well characterized; however, those of 36 genes were unknown. The expression of 29 genes was inhibited either by SB 203580, a specific inhibitor of p38 MAPK, or by CEP-11004, a specific inhibitor of the c-Jun-N-terminal kinase (JNK) cascade, and the percentage inhibition by SB 203580 correlated with that by CEP-11004, suggesting that p38 and JNK participate in a common downstream pathway involved in the regulation of gene expression. p38 MAPK- or JNK-dependent genes were functionally classified into diverse categories. Conclusions: Although further studies are needed to obtain a more complete understanding of gene expression and the role of MAPK in gene expression, the present results are important in understanding the molecular mechanisms involved in the response of bronchial epithelial cells to IV infection. [source] Voltage-dependent inhibition of the muscarinic cationic current in guinea-pig ileal cells by SK&F 96365BRITISH JOURNAL OF PHARMACOLOGY, Issue 4 2000A V Zholos The effects of SK&F 96365 on cationic current evoked either by activating muscarinic receptors with carbachol or by intracellularly applied GTP,S (in the absence of carbachol) were studied using patch-clamp recording techniques in single guinea-pig ileal smooth muscle cells. SK&F 96365 reversibly inhibited the muscarinic receptor cationic current in a concentration-, time- and voltage-dependent manner producing concomitant alteration of the steady-state I-V relationship shape which could be explained by assuming that increasing membrane positivity increased the affinity of the blocker. The inhibition was similar for both carbachol- and GTP,S-evoked currents suggesting that the cationic channel rather than the muscarinic receptor was the primary site of the SK&F 96365 action. Increased membrane positivity induced additional rapid inhibition of the cationic current by SK&F 96365 which was more slowly relieved during membrane repolarization. Both the inhibition and disinhibition time course could be well fitted by a single exponential function with the time constants decreasing with increasing positivity for the inhibition (e -fold per about 12 mV) and approximately linearly decreasing with increasing negativity for the disinhibition. At a constant SK&F 96365 concentration, the degree of cationic current inhibition was a sigmoidal function of the membrane potential with a potential of half-maximal increase positive to about +30 mV and a slope factor of about ,13 mV. Increasing the duration of voltage steps at ,80 or at 80 mV, increased the percentage inhibition; the degree of inhibition was almost identical at both potentials providing evidence that the same cationic channel was responsible for the cationic current both at negative and at positive potentials. It is concluded that the distinctive and unique mode of SK&F 96365 action on the muscarinic receptor cationic channel is a valuable tool in future molecular biology studies of this channel. British Journal of Pharmacology (2000) 129, 695,702; doi:10.1038/sj.bjp.0703115 [source] | ||||||||||