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In this study, fermentation of Allium chinense bulbs was carried out with Lactobacillus plantarum ZDY 2013. A decrease in pH from 6.8 to 3.5 and a stable lactic acid bacteria population were observed during 7-d fermentation. The total phenolic content increased by 2.7-fold in the aqueous and ethanol extracts of A. chinense bulbs after fermentation. Antioxidant capacity including 2,2-diphenyl-1-picrylhydrazyl radical-scavenging effect and reducing power of both extracts was significantly (P < 0.05) improved after fermentation. Antagonistic test against 6 pathogens showed that fermentation significantly (P < 0.05) enhanced the antimicrobial activity in both extracts of fermented bulbs, especially in the ethanol extracts of fermented bulbs against L. monocytogenes. Analysis of the free amino acid (FAA) profile by ion-exchange chromatography revealed that fermentation significantly (P < 0.05) increased total FAA content. In addition, among 27 kinds of volatile components analyzed by headspace-solid phase microextraction-gas chromatography-tandem mass spectrometry, sulfur-containing compounds accounted for 65.23%, but decreased to 43.65% after fermentation. Our results suggested that fermentation of A. chinense bulbs with L. plantarum could improve their biofunctionalities, and nutritional and chemical properties.

Starch biosynthesis, a very critical event during pollen development, is not well understood in terms of gene regulation and intracellularcontrols. Using the rice HL-type cytoplasmic male sterile (HL-CMS) line with starch deficiency in pollen and two related male-fertile lines (Oryza sativa L.), we have studied two specific developmental stages: 'early', that is, before or during pollen mitosis I, without starch accumulation, and 'late', the actively starch-filling postpollen mitosis I phase. Real-time reverse transcription-PCR analysis showed temporal changes in the expression patterns of six metabolic genes involved in the sucrose-starch pathway, i.e. sucrose synthase (EC 2.4.1.13), Rsus3; acid invertase (EC 3.2.1.26), OSINV2; phosphoglucomutase (EC 5.4.2.2), OsPGM; uridine diphosphate-glucose pyrophosphorylase (EC 2.7.7.9), OsUGP, a subunit of adenosine diphosphate-glucose pyrophosphorylase (AGPase) (EC 2.2.7.2), OsAGPL3; soluble starch synthase (EC 2.4.1.21), OsSSI and three transporter genes [sucrose transporter, OsSUT3; hexose transporter, OSMST7 and plasma membrane H + -adenosine triphosphatase (ATPase) (EC 3.6.1.35), OSA2]. Regarding metabolic enzyme activities, lower activity of sucrose synthase was detected at 'late' compared with 'early' stage in the three rice lines; invertase and other downstream enzymes had higher activities at 'late' stage in male-fertile but not male-sterile lines. Meanwhile, significantly reduced sugars and ATP levels were detected at 'early' and 'late' stages in male-sterile compared with male-fertile tissues. Furthermore, transgenic data showed that AGPase gene can stimulate starch accumulation in pollen of male-sterile host lines, showing the importance of AGPase in the metabolic pathway. Taken together, these data suggest that the combined effects of the reduced energy supply and sugar levels in starch biosynthesis may lead to the observed temporal changes in gene expression, and eventually to pollen sterility.

Deoxynivalenol (DON) poses a health risk to animals and humans consuming contaminated food and feed. Currently, no effective method had been established to detoxify DON. Obtaining strains for the detoxification of DON from probiotic strains and ascertaining the mechanisms of detoxification will be helpful for assuring food safety in food processing. In this research, two Bacillus strains possessing the capability of detoxifying DON were picked out from 59 probiotics by using a two-run screening. The strategy of adjusting pH and eightfold dilution was successfully applied to eliminate the interferences caused by MRS and nutrition broth in DON determination in competitive indirect enzyme-linked immunosorbent assay (ELISA). The capability of detoxification reached a high level when the spent culture supernatant of these two Bacillus were incubated at 37C, 180 rpm for 12 h, the detoxification rate were >98% and 71.4%, respectively. The rate presented a sharp decrease when the heating temperature changed from 65–75C. The detoxification potential was completely lost, when the heating temperature was 100C, whereas the viable cells were demonstrated as having no detoxification potential. The mechanism for detoxification of DON is related to some thermosensitive substances in the SCS of these two Bacillus. PRACTICAL APPLICATIONS Twenty-five percent of the global grains were contaminated by mycotoxins, resulting in the problem of quality and safety in food and feeds and also great economic loss. As one of the most popular mycotoxins in maize and wheat, deoxynivalenol attracted few many detoxification approaches. In our study, we have found that two probiotic strains of Bacillus presented stronger detoxification ability of deoxynivalenol, therefore they could be applied in the fermentation process of feedstuffs and fermented food. Furthermore, our research provided a protocol for searching the potential bacteria, which could be used for the detoxification of other mytoxins, e.g., aflatoxin B1, ochratoxin A, zearalenone, etc.