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Production of Cambodian rice wine involves complex microbial consortia. Indeed, previous studies focused on traditional microbial starters used for this product revealed that three microbial strains with complementary metabolic activities are required for an effective fermentation, i.e., filamentous fungi (Rhizopus oryzae), yeast (Saccharomyces cerevisiae), and lactic acid bacteria (Lactobacillus plantarum). Modulating the ratio between these three key players led to significant differences, not only in terms of ethanol and organic acid production, but also on the profile of volatile compounds, in comparison with natural communities. However, we observed that using an equal ratio of spores/cells of the three microbial strains during inoculation led to flavor profile and ethanol yield close to that obtained through the use of natural communities. Compartmentalization of metabolic tasks through the use of a biofilm cultivation device allows further improvement of the whole fermentation process, notably by increasing the amount of key components of the aroma profile of the fermented beverage (i.e., mainly phenylethyl alcohol, isobutyl alcohol, isoamyl alcohol, and 2-methyl-butanol) and reducing the amount of off-flavor compounds. This study is a step forward in our understanding of interkingdom microbial interactions with strong application potential in food biotechnology.

The objective of this study was to monitor the occurrence and levels of fumonisin B1 (FB1) and fumonisin B2 (FB2) in animal feeds distributed in South Korea in 2011. The contamination levels of FB1 and FB2 were investigated in 150 samples of compound feeds and in 40 samples of feed ingredients. The contamination rate of feed ingredients with FB1 and FB2 was 50 and 40%, respectively. FB2 was only found in samples contaminated with FB1. Of the compound feeds, 85% were contaminated by FB1 and 47% were contaminated by FB2. The highest contamination rate of FBs was observed in compound feeds for cattle (FB1: 100%; FB2: 80%), followed by poultry feed (FB1: 78%; FB2: 40%) and swine feed (FB1: 76%; FB2: 22%). The highest contamination level (14,600 ng/g) for FB1 were found in poultry broiler feed (early feeding period) samples, which had 82% contamination rate (9/11), and the highest level of FB2 (2,280 ng/g) was found in feed for fatting calves,which had a contamination rate of 100%.

Enormous economic losses caused by infection of peppers with Cucumber mosaic virus (CMV) have spurred the development of CMV-resistant peppers using genetic techniques. However, growing concern from the general public over genetically modified (GM) crops has focused attention on safety and labeling issues. In this study, we developed and optimized a qualitative and quantitative enzyme-linked immunosorbent assay (ELISA) to detect CMV-resistant GM peppers. Two types of antibodies, virion-derived polyclonal antibody (VPAb) prepared from a CMV-Fny virion-immunized rabbit and peptide-based polyclonal antibody (PPAb) prepared from rabbits immunized with a peptide fragment of CMVcoat protein (CMV-CP) (LPDSVTEYDKKLVSR) predicted from the nucleotide sequence were prepared, and their affinities were compared. Optimized ELISAs using VPAb and PPAb as the primary antibodies, respectively, were carried out to measure the level of CMV-CP in GM peppers cultivated at an officially approved facility in Korea. Color development (reflecting CMV-CP levels) was 2.5-fold higher when PPAb was used as the primary antibody compared to VPAb as the primary antibody. No statistical differences were observed among GM pepper cultivars. These results imply that PPAb has higher specificity for CMV-CP than VPAb does, and that the analytical system presented in this study can be used to evaluate the level of CMV-CP in genetically modified peppers.Additional key words: CMV-resistant pepper, Cucumber mosaic virus (CMV), enzyme-linked immunosorbent assay (ELISA), peptide-based polyclonal antibody Hort. Environ. Biotechnol. 56(3):316-323. 2015.

NeoN-methylsansalvamide is a novel low-molecular-weight cyclic pentadepsipeptide that exerts cytotoxic effects on various human cancer cell lines. Its structural analysis using liquid chromatography mass/mass spectrometry showed the cyclic structure sequence -phenylalanine-leucine-valine-N-methylleucine-leucic acid-. The intrinsic cytotoxic and multidrug resistance reversal effects of neoN-methylsansalvamide were evaluated on the human cancer cell lines MES-SA and HCT15 as well as on their multidrug resistance sublines (MES-SA/DX5 and HCT15/CL05, respectively) using the sulforhodamine B assay. The EC50 values of paclitaxel for MES-SA, HCT15, and for the multidrug resistance sublines MES-SA/DX5 and HCT15/CL05 were 1.00±0.20, 0.85±0.63, 10.00±0.53, and >1000 nmol/l, respectively. However, the EC50 values for paclitaxel including 3 μmol/l neoN-methylsansalvamide for MES-SA/DX5, HCT15, and HCT15/CL02 were 1.58±0.12, 0.10±0.02, and 288.40±21.02 nmol/l, respectively. The in-vitro multidrug resistance reversal activity of neoN-methylsansalvamide was similar to that of the control verapamil. These finding suggests that a novel cyclic pentadepsipeptide, neoN-methylsansalvamide, is effective in reversing multidrug resistance in vitro, and this activity may be a major applicable biological function of this compound.

Bacillus cereus is a Gram‐positive that is ubiquitous in foods and the wider environment. The B. cereus emetic toxin, cereulide, synthesized by nonribosomal peptide synthetase (NRPS), can cause either gastrointestinal disorders and/or emetic form of food poisoning. In this study, 108 B. cereus isolates from foods were tested for a correlation between the presence of emetic toxin genes and cereulide production. Based on 16S rRNA sequence analysis, 107 isolates were identical to B. cereus spp. Further experiments showed that fourteen isolates exhibited 1,271, 2,200 and 188‐bp bands, corresponding to amplification of the ces1, ces2 and NRPS gene, respectively. However, only 7 out of 13 strains possessing the NRPS, ces1, and ces2 genes produced cereulide in liquid culture. Strain number 93, isolated from fresh vegetables, produced the highest levels of cereulide (11.17 μg/mL); maximum cereulide levels were observed after 4 days of cultivation at 30C in LB broth. The amount of cereulide produced differed between each isolate. Practical Applications The incident of Bacillus cereus in food could cause food poisoning. The results of our study on the presence of B. cereus in spoiled foods demonstrated that not all the food poisoning B. cereus spp. have the ability to synthesize the emetic toxin, cereulide. Nonribosomal peptide synthetase and cereulide synthetase genes could be used as biological markers for differentiation of cereulide producing and nonproducing B. cereus. Estimation of cereulide level reveals that the amounts of cereulide produced by some strains were very high and could be a threat to human health if consumed in contaminated foods. This study presents proper methods to select cereulide producing food‐poisoning B. cereus spp. and gives more information on the condition of cereulide production to prevent future cases of emetic food poisoning.