Today, many different methods are applied for the correct use of foods and to prevent their deterioration. Ensuring healthy conditions for people in food consumption and consumption of healthy foods is very important for human welfare. In this study, food spoilage, the factors that cause food spoilage, its effects on a global basis, food transport systems (cold chain) and measures that prevent or delay food spoilage are discussed.

Purpose: Methods of tooth brushing are amply described, but procedures for maintaining their cleanliness are discussed infrequently. The purpose of this study was to evaluate the level of Microbial contamination of toothbrushes.Methods & Materials: The study has been done in a descriptive, retrospective, analytical way. Information about the methods of toothbrush care were obtained by a questionnaire filled by 100 individuals. Toothbrushes were gathered and examined in two culture media; Blood agar for gram positive microorganisms and E.M.B for gram negative microorganisms. All surfaces of a toothbrush were separately pulled three times on two culture media. Then culture media were incubated in 37°C and were read in three stages: 24, 48, 72 hours by eye and microscope. Level of Microbial contamination was divided into three groups on the basis of colony count. Low contamination: colonies < 10000, moderate contamination: 10000 - 30000, high contamination: > 30000. Statistical analysis in this study was as follows: 1- Chi - square for trends, 2- Fisher exact test, 3- Spearman correlation coefficient and 4 -Mann - Whitney test.Results: Overall 96% of toothbrushes were contaminated. Some variables such as type of toothbrushes, frequency of tooth brushing, time of toothbrush usage had no effect on CFU (Coloni forming unit). However, location of toothbrush for example toilet or bathroom, washing and drying method, use of cover after tooth brushing, oral hygiene had relationship with CFU. (P<0.05)Conclusions: Toothbrushes in regular use can become heavily contaminated with microorganisms. Storage conditions and skill in washing and toothbrush care are effective in reducing the level of their contamination.

Background: Occupational risk of dental personnel to Microbial airborne contamination has been demonstrated through the increased prevalence of respiratory infections. The American Dental Association has suggested stringent protection for infectious agents present in dental aerosols.Materials and Methods: Occupational exposure of dentists to airborne Microbial and mycological contamination in various locations of a dental school was monitored by sampling of air in close vicinity of their breathing zone. This sampler drew air at a flow rate of 10 liters/minute and for a 2-hour period and blew it at a high speed through a narrow slit over a solid nutrient agar plate. Immediately after sampling, the plates were placed in an incubator and incubated aerobically for 2 days at 37°C. Results: The total bacterial counts in the air of dental surgery rooms and in non-surgery rooms without direct involvements with dental operations were in the range of 120-280 cfu/m3 and 49-128 cfu/m3 respectively. Pathogenic Streptococcus haemolyticus and opportunistic Staphylococcus species were found in some locations of dental surgery rooms.Conclusion: There are no standards for acceptable levels of indoor air contamination with pathogenic microorganisms and since pathogenic Streptococcus haemolyticus and opportunistic Staphylococcus species were found in some areas of the dental school, the need for management of possible risk of infective hazards is recognized.

Background and Objectives: Bacterial contamination of blood products, especially platelets, may lead to bacterial sepsis or death and therefore is of concern. Many techniques have been explored to detect bacteria in blood products in order to prevent transfusion-related bacteria contamination and transmission. In the present study, four different methods were employed to detect 12 platelet units precontaminated with known bacteria.Materials and Methods: Ten units of platelet concentrates were inoculated at three levels (150, 15, and 1.5 CFU per ml) with Escherichia coli and Staphyococcus epidermidis. All of the platelet concentrates and two control units of platelet concentrates were stored at 20 to 24°C for five days. Every morning during storage, platelet concentrates were tested for platelet pH, plasma glucose, quantitative plate culture, and gram staining on platelet centrifuged smears.Results: Escherichia coli with 150 and 15 CFU per ml and staphylococcus epidermidis with 150 CFU per ml grew on culture medias after two days but staphylococcus epidermidis with 15 CFU per ml did after three days. The sensitivity rate of bacteria detection in platelet concentrates through gram staining was lower than quantitative culture. Despite lower plasma glucose level in platelet concentrates (as measured by hexokinase enzymatic method) inoculated with Microbial staines, pH level in platelet concentrates (as measured by pH meter) contentiously increased during five days of storage.Conclusions: The sensitivity rate of bacterial detection in platelet concentrates through measuring extra cellular pH was estimated to be higher than that of plasma glucose, culture and gram staining methods.

Background: Previous studies have shown that smokeless tobacco (SLT) products have a high Microbial load and may lead to various diseases. This study reviews Microbial contamination (bacteria, fungi, and viruses) of SLT products. Materials and Methods: The literature search was carried out in PubMed, Web of Science, Scopus, and Google Scholar databases in March and April 2024. Search results were limited to the English language. Two reviewers independently screened titles, abstracts, and full texts of the search results. For included studies, the data were extracted (year, country of the study, type of SLT, type of sampling, and Microbial communities). Results: About 50 bacterial species and 20 fungal species were observed in SLT products in previous studies. Among the bacterial agents, bacillus has the highest occurrence with 13 repetitions, followed by pseudomonas (9 repetitions). Furthermore, among the fungal agents, aspergillus has been repeated in 9 studies. Conclusion: Ensuring the processing, packaging, and storage of SLT products in hygienic conditions, as well as the implementation of strict rules to protect the health of users is strongly recommended.