What is the common inoculation amount of bacillus cereus vegetative cellsto rice samples?5 answersThe common inoculation amount of Bacillus cereus vegetative cells in rice samples varies across different studies. In a study conducted in Malaysia, 93.33% of raw rice samples were positive for B. cereus vegetative cells, with a mean log cfu/g ranging from 0.00 to 4.1533. Similarly, in Hong Kong, B. cereus was found in rice samples, with counts not exceeding 100 bacteria/g in most positive samples, but reaching up to 2×10^5 cells/g in poor quality rice. Additionally, a study in Pakistan reported that 25% of cooked/refrigerated rice samples were positive for B. cereus spores, leading to the germination and proliferation of vegetative cells under favorable conditions. These findings highlight the potential contamination levels of B. cereus in rice samples, emphasizing the importance of proper food handling and safety measures.
Can bacillus cereus thrive in salinity level of 34-35 in fish pond water?5 answersBacillus cereus strains have shown the ability to thrive in high salinity levels. Studies have isolated B. cereus strains from environments with salt concentrations as high as 10-25%. Additionally, B. cereus strains have been found to grow optimally in media containing 2-40% salt, indicating their tolerance to high salinity levels. Furthermore, B. cereus strains have been identified with the ability to tolerate salt, with some strains showing stronger salt-tolerant capacities than others. These findings suggest that B. cereus can indeed survive in salinity levels of 34-35 in fish pond water, as they have demonstrated adaptability to such high salt concentrations in various environments.
What is the crop growth rate of rice plant?5 answersThe growth rate of rice plants varies depending on different factors. Over the last 30 years, the average growth rate of rice cultivation has been approximately 0.39% per year. However, the growth rate of rice yield has shown a decline, decreasing from 3.68% per year in the early 1980s to 0.74% per year in the late 1990s. To meet the increasing demand for rice due to population growth, it is estimated that world rice production must increase by 2 million tons per year. Strategies to enhance rice yield potential include conventional hybridization, F1 hybrid breeding, modification of plant architecture, and enhancement of photosynthesis. Research and dissemination of data play a crucial role in addressing issues in rice cultivation and improving average yields at the farm level.
What is the role of Bacillus cereus in food poisoning?5 answersBacillus cereus is a spore-forming bacterium that plays a significant role in food poisoning. It is a common foodborne pathogen found in various sources such as foods, soil, water, plants, and fodder. B. cereus can cause gastrointestinal infections by colonizing the intestinal mucosa and impacting the microbial communities. It has been shown to induce modifications in the intestinal microbiota, reducing levels of certain bacteria like Escherichia coli, Lactobacillus, and Akkermansia, while increasing abundances of Bifidobacterium and Mitsuokella. Additionally, B. cereus produces various toxins, including cytotoxin K-2 and cereulide, which can cause food poisoning. The presence of potentially pathogenic and drug-resistant B. cereus in food and feed additives highlights the need for research to assess the threat it poses to consumers. Controlling methods to prevent B. cereus contamination and cereulide production in food processing lines are crucial for improving microbial risk management in the food industry.
Isolation and characterization of Bacillus cereus bacteriophage DZ1 and its application in foods,4 answersBacteriophage DZ1, isolated from Indonesian traditional Ready-to-Eat (RTE) food, has been characterized and its application in controlling Enterotoxigenic Escherichia coli (ETEC) in various foods has been determined. The phage DW-EC, isolated from Indonesian traditional RTE food called dawet, showed lytic activity against ETEC and belonged to the Myoviridae family. Molecular characterization and bioinformatic analysis indicated that DW-EC exhibited characteristics as a promising biocontrol agent in food samples. DW-EC significantly reduced the ETEC population in various food samples, including chicken meat, fish meat, cucumber, tomato, and lettuce. The results suggest that bacteriophage DZ1 has potential applications in controlling ETEC in foods.
How does fermentation time affects the pH level of roasted rice?5 answersFermentation time has been found to affect the pH level of roasted rice. In one study, it was observed that during fermentation, there was a decrease in pH with the concomitant increase in total reducing sugar content. Another study found that natural fermentation for 72 hours slightly affected the protein content and composition of rice flour, which could potentially impact the pH level. Additionally, in the context of dosa batter, it was determined that the best fermentation time was 12 hours, which resulted in the highest scores for sensory attributes such as appearance, texture, flavor, taste, and overall acceptance. Although specific pH values were not mentioned in these abstracts, it can be inferred that longer fermentation times may lead to a decrease in pH due to changes in sugar content and protein composition.