摘要:
<jats:p>Genistein is one of major isoflavones derived from soybean products and it is believed to have beneficial effects on human health. However, its low water-solubility and poor oral bioavailability severely hamper its use as a functional food ingredient or for pharmaceutical industry. In this study, zein and zein/carboxymethyl chitosan (CMCS) nanoparticles were prepared to encapsulate genistein using a combined liquid–liquid phase separation method. The physicochemical properties of fabricated nanoparticles were characterized by dynamic light scattering (DLS), atomic force microscopy (AFM), and Fourier transform infrared spectroscopy (FTIR). The results demonstrated that genistein encapsulated with zein nanoparticles significantly improved its water dispersibility, antioxidant activity in the aqueous phase, and photostability against UV light. Moreover, genistein encapsulated in zein nanoparticles showed a sustained release property. Furthermore, it was found that encapsulation efficiency of genistein was significantly enhanced after CMCS coating, and this effect was more pronounced after the complex nanoparticles cross-linked with calcium ions when compared with the use of zein as a single encapsulant. In addition, compared to zein nanoparticles without biopolymer coating, CMCS coating significantly enhanced the thermal and storage stability of the formed nanoparticles, and delayed the release of genistein. A schematic diagram of zein and zein/carboxymethyl chitosan (CMCS) nanoparticles formation mechanism for encapsulation of genistein was proposed. According to the results of the current study, it could be concluded that encapsulation of genistein in zein/CMCS nanoparticles is a promising approach to improve its water dispersibility, antioxidant activity, photostability against UV light and provide controlled release for food/pharmaceutical applications.</jats:p>
摘要:
Fermented sausages have a long tradition originating from China. In this study, three starter microorganisms including Pediococcus pentosaceus (P), Staphylococcus xylosus (S), and a combination of P. pentosaceus and S. xylosus (P + S) were conducted for the manufacture of traditional Xiangxi (a city in China) fermented sausages. The physicochemical changes of the above three kinds of sausages during fermentation were studied and discussed, and also compared with these properties on the natural fermented sausage (N, i.e., control). The results revealed that five kinds of bacterial phases were existed at different fermentation stages in N, P, S and P + S fermented sausages, respectively. The microbiological data showed that an initial enterobacteria count of approximately 5.3 log CFU/g for all four batches of sausages. The enterobacteria count in the inoculated sausages of P and P + S groups decreased significantly to about 1 log CFU/g whereas group N and S had a count of about 3.3 log CFU/g after fermentation. In the early stages of fermentation, the pH rapidly decreased below 5.3. FAA and FFA were significantly increased in all groups and TBARS value in group P was higher than that of the other three groups. In conclusion, starter cultures can be used to improve the hygiene level of Xiangxi sausages without significant effects on pH, AW, and nitrite residue.
摘要:
<jats:title>Abstract</jats:title><jats:sec><jats:label /><jats:p>The chewing of areca nut is closely associated with human diseases such as oral submucous fibrosis and immune related diseases. Recent studies have focused on the pharmacological and toxicological effects of areca nut chewing, and have largely overlooked the effects on intestinal microbiota. In this study, we sought to understand how different methods of areca consumption affect intestinal microflora composition. A total of 60 male and 60 female Kunming mice were each randomly divided into six groups and fed different areca preparations to mimic different areca nut chewing habits. The preparations included fresh areca fruit; areca fruit with betel leaf or cured tobacco; brined areca; smoked brined areca; and a control. The fecal microbiota of mice in the 12 groups was compared after 28 days of oral gavage administration. To determine the composition and diversity of the fecal microbiota, we performed high‐throughput sequencing of bacterial 16S rRNA. In both male and female mice, the diversity and abundance of the intestinal microbiota of the experimental groups were higher than those in the control groups. Furthermore, different areca preparations had different effects on the diversity, abundance, and composition of the intestinal flora of Kunming mice.</jats:p></jats:sec><jats:sec><jats:title>Practical applications</jats:title><jats:p>The chewing of areca nuts in various forms is widespread in Asia and other areas. This manuscript first explores the effects of different areca nut chewing habits on the gut microbiota of mice. We then further clarify the impact of different areca nut chewing habits on intestinal health and provide a new direction for areca nut research. In addition, our findings will increase public understanding of areca nut usage and provide guidance for the areca nut industry.</jats:p></jats:sec>
摘要:
To analyze oral microbial diversity in the saliva of 8 healthy individuals before and after chewing areca nuts. Saliva samples were collected before chewing areca nuts, after chewing areca nuts for 5 min and after chewing areca nuts for 30 min. DNA was extracted, and microbial diversity was examined using PCR-denaturing gradient gel electrophoresis (PCR-DGGE). When examining DGGE profiles collectively, the bands associated with Streptococcus and Veillonella were the most intense, making them the most prevalent bacteria. Furthermore, the band intensities did not decrease after chewing areca nuts for 5 or 30 min; thus, these bacteria were unaffected. However, when examining some individuals, the band intensities for Streptococcus and Veillonella became more intense after 5 min of chewing and then returned to the pre-chewing level. This difference may be attributed to the mechanical movements of the oral cavity or individual differences. Other bacteria, such as Neisseria, Actinomycetes, and Rothia dento-cariosa, were also found to have an increased or decreased prevalence following areca nut-chewing. Since the predominant species that are present following areca nut-chewing include Streptococcus and Veillonella, it would seem likely that these bacteria play an important role in the periodontal diseases associated with areca chewing. (C) 2018, Chinese Association of Animal Science and Veterinary Medicine. Production and hosting by Elsevier B.V. on behalf of KeAi Communications Co., Ltd.
摘要:
Catechin exhibits antimicrobial activity against various microorganisms, such as EHEC O157:H7. This study reports the bactericidal effect of catechin on EHEC O157:H7 in simulated human gastrointestinal environment and the underlying antibacterial mechanism. Bacteriostasis test results showed that the minimum bactericidal concentration of catechin for EHEC O157:H7 was 5 g/L. The bactericidal effect of catechin in the gastrointestinal juice became more significant with increased culture time, and catechin exhibited a synergistic effect with bile salt in inhibiting EHEC O157:H7. Changes in the profile of protein expression in EHEC O157:H7 in response to catechin intervention were investigated. Two-dimensional electrophoresis identified 34 proteins with significantly altered expression. A total of 2 and 12 proteins were upregulated and downregulated, respectively. However, 20 proteins disappeared. No new protein was expressed compared with the control. Hence, catechin intervention resulted in diverse changes in the expression of proteins associated with cell structure and genetic information processing. Catechin could cause the disappearance of certain proteins or the destruction of certain peptides. These processes lead to the inhibition of EHEC O157: H7 cells.