Inactivation of Byssochlamys fulva during ohmic heating of tomato juice.

Ohmic heating is an emerging direct thermal technology, which uses electricity to heat food products volumetrically. Ohmic heating provides thermal and non-thermal effects like electropermeabilization to inactivate microorganisms. In this study, ohmic heating was used to inactivate Byssochlamys fulva in tomato juice. The main and interaction effects of initial pH (3.5 and 4.5) and voltage gradient (15 and 20 V/cm) were investigated on mold inactivation during ohmic heating at 88, 93, and 98 °C for 20, 10 and 5 min, respectively. The pH, acidity, total soluble solids, and Dvalue were compared. The results showed that pH and voltage gradient had significant effects on Dvalue and Zvalue (p < 0.05). In order to model the survival behavior of Byssochlamys fulva, due to the nonlinearity of the curves, Weibull model gave more accurate estimation compared to classical first-order model.

Predisposing factors of important invasive fungal coinfections in COVID-19 patients: a review article.

Severe acute respiratory syndrome coronavirus-2 has caused a devastating pandemic lasting for more than a year. To date, 47 million individuals have been infected and 1.2 million individuals have died worldwide. Some of the most important coinfections in patients with coronavirus disease 2019 (COVID-19) are opportunistic invasive fungal infections (OIFIs), which are sometimes not rapidly diagnosed and are often diagnosed after death. Aspergillosis and candidiasis are the most prevalent OIFIs in patients with COVID-19. Mycormycosis, cryptococcosis, and other fungal diseases have also been documented more rarely. This review aimed to summarize factors affecting COVID-19 transmission, prevalence, morbidity, and mortality in Iran as well as to review common OIFIs in patients with COVID-19. Immunological factors, underlying diseases, and social, cultural, and environmental factors can affect COVID-19 transmission. There is a need to improve diagnostic and therapeutic criteria for OIFIs and to optimize management procedures so that patients with OIFIs can receive treatment as rapidly as possible. Screening of patients with confirmed COVID-19 for OIFIs at the treating physician's discretion could enable early OIFI diagnosis, treatment, and mortality reduction.

Identification of saprophytic and allergenic fungi in indoor and outdoor environments.

The airborne spores of some saprophytic and allergenic fungi such as Aspergillus, Alternaria, and Cladosporium are found throughout the world and exposure to these agents may result in various types of allergic diseases. The aim of this study, therefore, was to investigate the frequency of different saprophytic, allergenic, and pathogenic fungi in indoor and outdoor environments. During a 6-month period, 780 samples were obtained from a number of houses, mosques, parks, public restrooms, grocery stores, laboratories, and hospitals. An open-plate method was applied for air sampling by exposing 90-mm plates containing chloramphenicol/potato dextrose agar and malt extract agar were exposed to air for 30 min. Alternatively, the sampling from surfaces was performed using sterile wet swab and tape-stripe method. All samples were then inoculated in media and incubated at 28 °C for 2-3 weeks. The isolated fungi were purified in order to detect the genus, and if possible, species level of the targeted fungi based on morphological and microscopic features using standard methods. The findings revealed that the dominant indoor and outdoor fungal species were Aspergillus, Penicillium, and Cladosporium whose frequency values were 16.42%, 16.17%, and 14.92% respectively. The lowest frequency was related to Acrophialophora and Madurella (0.25%). More notably, the results for air and surface were similar. It was also found out that the three dominant genera were Aspergillus (16.53%), Penicillium (15.50%), and Cladosporium (11.93%), with Basidiobolus and Acrophialophora having the lowest frequency. It was observed that different environmental spaces have a great bearing on the spreading of such allergic agents, especially in subtropical humid climates.

Molecular Identification of Mucor and Lichtheimia Species in Pure Cultures of Zygomycetes.

BACKGROUND: The Mucorales are an important opportunistic fungi that can cause mucormycosis in immunocompromised patients. The fast and precise diagnosis of mucormycosis is very important because, if the diagnosis is not made early enough, dissemination often occurs. It is now well established that molecular methods such as polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) are feasible and reliable tools for the early and accurate diagnosis of mucormycosis agents. OBJECTIVES: The present study was conducted to evaluate the validity of PCR-RFLP for the identification of Mucorales and some important Mucor and Lichtheimia species in pure cultures of Zygomycetes. MATERIALS AND METHODS: Specific sense and anti-sense primers were used to amplify the Mucorales, Mucor, and Lichtheimia DNA. The PCR products were digested by AfIII, XmnI, and AcII restriction enzymes, and the resultant restriction pattern was analyzed. RESULTS: On the basis of the molecular and morphological data, we identified Mucor plumbeus (10.83%), M. circinelloides (9.17%), Lichtheimia corymbifera (9.17%), M. racemosus (5.83%), M. ramosissimus (3.33%), and L. blakesleeana (0.83%). CONCLUSIONS: It seems that PCR-RFLP is a suitable technique for the identification of Mucorales at the species level.

Isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings.

BACKGROUND: Invasive fungal infections cause considerable morbidity and mortality in immunocompromised hosts. Pigeon droppings could especially be a potential carrier in the spread of pathogenic yeasts and mold fungi into the environment. The objective of this study was to isolation of Cryptococcus neoformans and other opportunistic fungi from pigeon droppings. MATERIALS AND METHODS: One hundred twenty samples of pigeon droppings were suspended 1:10 in saline solution and then cultured. Identification of C. neoformans was performed on bird seed agar, presence of a capsule on India ink preparation, urease production on urea agar medium and RapID yeast plus system. The identification of candida species was based on micro-morphological analysis on corn meal-Tween 80 agar, RapID yeast plus system and growth in CHROMagar candida. The identification of other fungi was based on macromorphologic, microscopic, biochemical and physiological characteristics. RESULTS: The highest frequency of yeasts and mold fungi were observed in Candida albicans 6.6% and Penicillium spp. 25%. The frequency rate of C. neoformans isolation was 2.5%. CONCLUSION: Several types of fungi are present in pigeon droppings that can spread in environment and transmit to children and elderly as well as immunocompromised patients who are at increased risk of contracting opportunistic diseases.