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31.
Jean‐Pierre Guyot 《International Journal of Food Science & Technology》2012,47(6):1109-1114
Cereal‐based fermented foods are major contributors to energy intake in developing countries (DC). Their microbiota is dominated by lactic acid bacteria and has been extensively investigated. Diversity studies have been facilitated by molecular methods enabling genotyping of isolates; the rapid development of ‘omics’ approaches should facilitate more comprehensive studies to describe the relation between microbial diversity, cell physiology and product characteristics. Also, the link between the food microbiota and health benefits, in particular in nutrition, should be investigated. There is a need to encourage researches in the field of DC cereal‐based foods in direction of more mechanistic approaches. 相似文献
32.
The purpose of this study was to investigate the absorption mechanism of vitexin-2″-O-rhamnoside, the index component in hawthorn leaves flavonoids (HLF) in the rat intestine, using two different absorption models, the in situ single-pass intestinal perfusion and the in vitro everted gut sac model. The effective permeability coefficients (Peff) in the in situ single-pass intestinal perfusion experiments and the apparent permeability coefficients (Papp) in the in vitro everted gut sac experiments were calculated. Furthermore, the influences of the P-glycoprotein inhibitors, verapamil and digoxin, on the intestinal absorption of vitexin-2″-O- rhamnoside in HLF were studied using the above-mentioned two models. Results showed that there were no significant differences in the absorption of vitexin-2″-O-rhamnoside in HLF in four segments of the rat intestine, duodenum, jejunum, ileum, and colon, and at different concentrations of HLF ranging from 0.05 mg/ml to 0.5 mg/ml (P > 0.05). The Peff values for vitexin-2″-O-rhamnoside in the rat jejunal perfusion at the concentration of 0.05, 0.1, 0.25, and 0.5 mg/ml were (2.48 ± 0.33) × 10?5; (2.23 ± 0.67) × 10?5; (2.18 ± 0.48) × 10?5; and (2.25 ± 0.17) × 10?5 cm/s, respectively. But there was significant difference between absence and presence of verapamil or digoxin (P < 0.05). Peff and Papp values of vitexin-2″-O-rhamnoside in HLF were increased in the presence of verapamil or digoxin. In conclusion, vitexin-2″-O-rhamnoside can be classified into high permeability class drug according to the biopharmaceutical classification system. Passive diffusion dominates the absorptive transport behavior of vitexin-2″-O-rhamnoside in HLF. The absorption and secretion are mediated by the efflux transport system, P-gp. The absorption of vitexin-2″-O-rhamnoside in HLF can be enhanced administered together with P-gp inhibitors. 相似文献
33.
《Drug development and industrial pharmacy》2013,39(3):310-319
Context: Humic acid (HA) is omnipresent in natural organic matter that is a macromolecular, negatively charged polyelectrolyte that contains a hydrophobic core. It is also present in a significant amount in Shilajit (used frequently in traditional medicines), which is used in this study as a source of extraction. HA is evaluated for the oral drug delivery of carbamazepine (CBZ). Objective: HA is used in this study to increase the dissolution, intestinal permeation, and pharmacodynamic response of CBZ (bio pharmaceutics classification system (BCS) II) by the technique of complexation and other related mechanism reported with humic substances. Methods: Different complexation techniques were explored in this study for the entrapment of CBZ, which was authenticated by molecular modeling and conformational analysis. These were further characterized using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). Solubility analysis and dissolution release profile were carried out to access the in vitro parameters. For ex vivo studies, rat gut intestinal permeability was done. And finally pharmacodynamic evaluation (maximal electroshock method) was carried out for optimized complexes. Results: Molecular modeling approach and instrumental analysis (DSC, XRD, and FT-IR) confirmed the entrapment of CBZ inside the complexing agent. Increased solubility (~1742%), sustained release (~78%), better permeability (~3.5 times), and enhanced pharmacodynamic responses conferred the best to 1:2 freeze dried (FD) and then 1:2 kneading (KD) complexes compared with pure CBZ. Conclusion: Now it could be concluded that HA may be tried as a complexing agent for antiepileptic drug and other classes of low water-soluble drug. 相似文献
34.
35.
Thapakorn Chumphon Kanjana Pangjit Saran Promsai 《International Journal of Food Science & Technology》2021,56(5):2182-2192
This study found that the isolated probiotics Lactobacillus paracasei KUKPS6201, L. acidophilus KUKPS6107, L. reuteri KUKPS6103, L. rhamnosus KUKPS6007, L. salivarius KUKPS6202, Bacillus coagulans KPSTF02 and Saccharomyces boulardii KUKPS6005 had high potential for probiotic properties. All strains had antibacterial activity and high antioxidant activity of 1.654 ± 0.017 mg Trolox mL−1 probiotic extract. The selected strains could survive in a simulated gastrointestinal tract under anaerobic conditions and showed no haemolytic activity. Furthermore, the probiotic strains were strongly auto-aggregated and also showed co-aggregated ability with pathogenic bacteria. The probiotic microorganisms demonstrated high ability to adhere to Thai-pigmented rice grains. The results of analysis of these probiotics showed that Riceberry rice bran oil was an excellent prebiotic. A synbiotic product containing Thai-pigmented rice grains (cultivar Riceberry, Luem Pua and Black Jasmine) and rice bran oil was produced. After 8 weeks of storage, the viability of the probiotics in terms of multistrains was 7.36 ± 0.04 log CFU g–1 (85.78% survival rate). Microbiological safety testing indicated that the amounts of contaminants were acceptable. This study provided the first scientific report on the feasibility of applying Thai-pigment rice, rice bran oil and mixed-culture probiotics as a novel functional synbiotic product. 相似文献
36.
37.
Nancy J. McGraw Nida Napawan Mitchell R. Toland John Schulze Barry M. Tulk Elaine S. Krul 《Journal of food science》2014,79(9):H1832-H1840
Consumption of protein hydrolysates has been proposed to stimulate muscle anabolism more than intact (nonhydrolyzed) proteins via accelerated delivery of amino acids for muscle protein synthesis (MPS). We evaluated whether the rate of amino acid uptake and transport across intestinal cells was enhanced for soy protein hydrolysates versus nonhydrolyzed soy protein. Intact and partially hydrolyzed proteins were subject to simulated gut digestion and applied to the apical surface of Caco‐2 monolayers. Basolateral media was harvested after 3 h and quantitatively analyzed for free amino acids using ion‐exchange chromatography and comparison to an included reference standard. Basolateral concentrations of all amino acids were higher (mean 32%) for hydrolyzed versus nonhydrolyzed protein with the greatest differences in histidine, lysine, and valine. Scale‐up production of the soy protein hydrolysate did not diminish its enhanced absorption properties. These data support the hypothesis that hydrolyzed soy protein may provide dietary amino acids that are more rapidly transported across the intestinal epithelium versus intact soy protein. This would be important under conditions where rapid and increased levels of amino acids are needed such as in the stimulation of MPS. 相似文献
38.
Shiho Suzuki Mariko Ono Toshiya Toda Shinichi Kitamura 《Journal of Applied Glycoscience》2016,63(1):1
We studied the structure of alginates extracted from five commercial Saccharina (Laminaria) species including three varieties (eight samples in all) harvested in Hokkaido, Japan. The algae used were Saccharina japonica, S. japonica var. diabolica, S. japonica var. ochotensis, S. japonica var. religiosa, S. longissima, S. coriacea, S. angustata, and S. sculpera (Kjellmaniella crassiforia). These alginates have molar fractions of mannuronic acid (FM) ranging from 0.68 to 0.76 and weight average molecular weights (Mws) ranging from 511,000 to 616,000. Alginate samples from both S. angustata (FM = 0.76) and S. longissima (FM = 0.68) showed intestinal immunological activity through Peyer’s patch cells of C3H/HeJ mice. Low molecular weight S. angustata alginate (FM = 0.75, Mw = 70,000) degraded using a wet pulverizing system showed higher activity than the native one. 相似文献
39.