Chapters authored
Biopesticide of Neem Obtained by Enzyme-Assisted Extraction: An Alternative to Improve the Pest Control
The indiscriminate use of chemical pesticides to control pests and diseases without technical assistance instead of solving the pest problems has caused environmental damage, agriculture productivity, and human health. Pesticides can remain for several years in the soil, being able to contaminate rivers and lagoons, animals of shepherding and foods. Besides, in recent years, pests have shown an alarmingly resistance over several pesticides. This makes necessary the use of other natural sources of pesticides that could be degraded avoiding the resistance problem. One of the main sources analyzed is the neem (Azadirachta indica) due to its complex content of bioactive triterpenoids. However, cellulosic structures of cell wall conditioned the extraction of these components, acting as physical barrier and avoiding its complete extraction. This chapter included a review of the consequences of the use of chemical pesticides to control pests spread in plant and animals and its repercussions on the environment. Moreover, the advantages of the use of food-grade enzyme preparations as an alternative to elaborate an extract of neem without organic solvents are exposed. The results are promissory and could improve the acaricide and repellent effects of the neem extracts over pests, reducing the negative effect caused by chemical pesticides.
Part of the book: Soil Contamination and Alternatives for Sustainable Development
Survival Differences of Vibrio vulnificus and Vibrio parahaemolyticus Strains in Shellstock Oysters (Crassostrea virginica) from Harvest to Sale: A Risk Perspective
As there is limited information on the risk for consuming market oysters contaminated with V. vulnificus and V. parahaemolyticus, the aim of this study was to estimate the risk associated with raw oyster consumption affected by contamination levels and temperature during postharvest and transportation. To evaluate the effect of the temperature during transportation from the Mandinga Lagoon to Mexico City on the growth of V. vulnificus and V. parahaemolyticus, a modified Gompertz model was fitted at ambient temperatures of 20.1, 25.6, and 24.4°C for 22 h in windy, dry, and rainy seasons, respectively. The risk was calculated using FDA/FAO/WHOv.2005 software. Results showed that the mean risk (cases per 100,000 servings) of a person acquiring V. vulnificus vvha+/cvgC infection by consuming raw oysters was 2.9 × 10−6, 4.7 × 10−6, and 4.3 × 10−6 during windy, dry, and rainy seasons, respectively. Risk for consuming oysters during windy season at-harvest contaminated with V. parahaemolyticus tdh+ was 8 × 10−6 and 7.8 × 10−7 for consuming oysters at-market during rainy season contaminated with V. parahaemolyticus tdh+ and trh+. These results suggest that maintaining temperatures above 20°C during oyster storage and transportation increases the risk of infections by pathogenic strains. The results provide a benchmark information to establish strategies to improve public health.
Part of the book: Molluscs