Effect of in-package gas composition on growth and aflatoxin production of Aspergillus flavus in culture medium and red pepper.

In this study, the effect of in-package gas composition on growth and aflatoxin production of toxigenic Aspergillus flavus was investigated. For this purpose, semi-dried red pepper samples and potato dextrose agar media with different pH values (3.5, 5.6, 7.0 and 9.0) were inoculated with A. flavus and packaged under different gas atmospheres (air, 100% N2, 70% N2 + 30% CO2 and 100% CO2). The growth of the fungus was monitored during storage at 25 °C for 8 days and the aflatoxin levels produced were determined at the end of storage. The highest growth rate was observed in the medium at pH 9.0 and the highest toxin production was in the medium at pH 5.6. Slowdowns up to 55.6% and 28.0% in the growth of A. flavus in the culture medium and red pepper were observed when packaging under 100% N2 was employed. It was found that 70% N2 + 30% CO2 atmosphere was more effective than 100% N2 in inhibiting the growth of A. flavus in red peppers; however, the difference between the aflatoxin levels produced in the samples packaged under these gas compositions was not significant (p > 0.05). CO2 concentrations higher than 90% in the package were quite effective against A. flavus resulting in 60% and 99% reductions in the growth and aflatoxin production of the fungus in red pepper.

Mold infestation and aflatoxins production in traditionally processed spices and aromatic herbs powder mostly used in West Africa.

Mold infestation and occurrence of aflatoxins were investigated in 66 samples of dried spices and aromatic herbs powder (SAH) as commercialized in Benin and its neighboring countries. The samples were randomly collected from markets, supermarkets, and processing sites. Mold counts were enumerated according to standard method and aflatoxins levels were assessed using high-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD). The results revealed that mold counts of samples ranged between 2.62 and 4.34 LogCFU/g. Aflatoxin B1 contents were between 0.46 µg/kg and 84.84 µg/kg with 40% of samples exceeding the recommended limit of 5 µg/kg. Aflatoxins G1 and G2 levels were low in general with means values varying from 0.24 to 8.56 µg/kg, and 0.11 to 3.68 µg/kg, respectively. Fifty-two percent (52%) of samples analyzed contained total aflatoxins levels lower than the stipulated limit of 10 µg/kg, whereas 92% of them were contaminated at various levels with one type aflatoxin, B1 or B2, G1 or G2. This study provides the first information about the occurrence of aflatoxins in the common spices used in West Africa.

Comparative Study of Predominant Phytochemical Compounds and Proapoptotic Potential of Broccoli Sprouts and Florets.

The study compares lyophilized broccoli sprouts and florets in terms of their chemical composition, cytotoxic and proapoptotic potential against hepatocellular carcinoma HepG2, colorectal cancer SW480, and skin fibroblast BJ cells. Sinapic and isochlorogenic acids were predominant phenolics in the sprouts and florets, respectively. The amount of sulforaphane in the sprouts was significantly higher vs. florets. Oleic and linoleic acids dominated in the sprouts, while caproic, stearic and oleic acids in the florets. Broccoli sprouts were selectively cytotoxic on HepG2 and SW480 cells, with proapoptotic effect for the latter, while the florets were less selective, but more active, with profound proapoptotic effect for HepG2 cells (77.4%). Thus, lyophilized broccoli sprouts may be effectively used in dietary chemoprevention.

Spray-dried powders improve the controlled release of antifungal tioconazole-loaded polymeric nanocapsules compared to with lyophilized products.

This work aimed to obtain solid formulations from polymeric nanocapsules and nanoemulsions containing tioconazole, a broad spectrum antifungal drug. Two dehydration methods were used: spray-drying and freeze drying, using lactose as adjuvant (10%, w/v). The liquid formulations had a mean particle size around 206 nm and 182 nm for nanocapsules and nanoemulsions, respectively, and an adequate polydispersity index. Tioconazole content was close to the theoretical amount (1.0 mg/mL). After drying, the content ranged between 98 and 102%with a mean nanometric size of the dried products after redispersion. Scanning electron microscopy showed that the particles are rounded, sphere-shaped for the dried products obtained by spray-drying, and shapeless and irregular shapes for those obtained by freeze-drying. In the microbiological evaluation, all dried products remained active against the yeast Candida albicans when compared to the original systems. The dried products obtained by spray-drying from nanocapsules presented better control of the tioconazole release when compared to the freeze-drying products.