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Category: Mycology

Role of selenium-fortified yogurt against aflatoxin-contaminated nuts

Aflatoxins produced by a certain molds that are poisonous carcinogens which grow mostly in soil, hay, decaying plants and grains. It can affect livestock and human as natural contaminants in foods like peanuts and corn meal. There are four types of aflatoxins these are B1, B2, G1 and G2 in which all are teratogenic, carcinogenic and immunosuppressive. Its toxic effect might be due to the generation of free radicals resulting into lipid peroxidation that damage biological system. On the other hand yogurt is produced from the bacterial fermentation of milk. In which bacteria produces lactic acid that acts on milk protein to give yogurt its texture and tart flavor. However, yogurt contains plenty of probiotic bacteria that offer benefits as microflora in the intestines. It also helps boost immune response and suppress carcinogenesis since fermented dairy products contain live lactic acid bacteria.


Selenium-fortified yogurt protects against aflatoxin toxicity

Yogurt has been known as therapeutic to various disorders including lactose intolerance, indigestion, intoxication, gastroenteritis, kidney, liver disorders and cancer. Selenium added to yogurt considered as the basic trace elements vital for normal growth and development in humans and animals. It also acts as anti-oxidant as well as improves nutritional values. Additionally, selenium has both enzymatic and structural functions that protect harmful reactive oxygen and minimized the production of hydrogen peroxide from aflatoxins. Ingestion of aflatoxins leads to weight loss due to the change in digestive enzymes activity that causes malabsorption of nutrients.


Aflatoxins will impair the biosynthesis of protein which results to the degranulation of the endoplasmic reticulum. It also caused liver fibrosis and poses health risk to humans and livestock. In this research , a positive results shows that selenium-fortified yogurt suppress the level of aflatoxins in rats. It also proved that with selenium contents inhibit the activity of enzymes related to carcinogenesis. Since yogurt improves intestinal mucosa and microflora that influence intestinal barrier. These yogurt bacteria inhibit the peroxidation of lipids by foraging reactive oxygen.


Therefore, consumption of nuts infected with aflatoxins caused toxicity mainly at the kidney and liver. But intake of selenium-fortified yogurt can definitely suppress against aflatoxins toxicity. In general, application of probiotic bacteria and selenium is vital and viable therapeutic approach to improve safety in food industry. Indeed, it is recommended to eat fresh nuts to avoid aflatoxins along with selenium-fortified yogurt to lessen its toxicity.


Source: Prepared by Joan Tura from BMC Agriculture and Food Security

Volume 7:21, June 2018



Cladosporium species in indoor environments

Cladosporium is a fungus that mostly found in indoor and outdoor molds. It is a species that formed in simple or branching chains and produced olive-green to brown colonies with pigmented conidia. Many of these Cladosporium species commonly found on living and dead plant materials. In which spores are dispersed by the wind that is why it is extremely abundant in outdoor air. On the other hand indoor species may grow when moisture of the surface is present. These species also belongs to a monophyletic group that is well bounded by having a unique coronate structures. In this current research a multilocus DNA sequence typing approach been conducted. As well as morphological examinations and cultural characteristics used as basis for identification and delimitation.


Diversity of Cladosporium in indoor environments

Cladosporium phylogeny and taxonomic structures have been reviewed extensively however, no enough study conducted about its presence in indoor environments. A molecular phylogenetic approach has been made to identify common indoor species. Since fungi usually present in indoor environment that produced toxins or holds allergens which cause hazards on health. That is why it is very important to know what are fungal species thrives indoors.


There were 46 species found indoors wherein four are found to be human-derived samples. Sixteen species identify as new in which 6 belong to Cladosporium complex and the most common are Cladosporium halotolerans. These indoor species grow better compared to other indoor fungi such as Aspergillus and Penicillium. As part of worldwide survey of the indoor mycobiota about 520 new Cladosporium isolates collected mainly from China, Europe, North America, South Africa and New Zealand.


Moreover, Cladosporium exhibits very condensed growth pattern forming round pigmented cells in the central colony and quick spore formation. It can also grow at lower available nutrients and the ability to deal with humidity changes in indoor situations. Interestingly the availability of water for these fungi is highly dynamic and influenced by changing temperature. The pure morphological identification of Cladosporium is clearly possible with the aid of molecular data and Cladosporium halotolerans is the most frequently isolated Cladosporium species indoors.


Source: Prepared by Joan Tura from  Studies in Mycology

Volume 89, March 2018, Pages 177-301



Synthesis and Investigations on Tellurium Myco-nanoparticles

Nanotechnology is a growing discipline in tech economy wherein nanoparticles became part of everyday life. Nanoparticles a substance having a size less than 100nm used mostly in industrial products including clothing, cosmetics, foods and drugs. Although it shows adverse effects on humans, animal and environment but different properties of it are useful for many applications. Consequently, careful assessment upon usage of nanoparticles is needed to provide safety during speedy commercialization of nanotechnology.


Nanoparticles extracted from fungi

Recent findings of biogenic production of nanoparticles became superior compare to that of chemical methods. Microbial nano-biotechnology attracted more attention in the development and progress on the field of chemistry, engineering and biological science. Since, production of biogenic nanoparticles will not release toxic and harmful wastes. But it is a “green” environmental friendly method that requires less energy compared to chemical process. Tellurium nanoparticles are produced from microbial cells.  In this current study investigates the most active fungi that produced tellurium through enzymatic process to obtain pure nanoparticles.


On the other hand tellurium is a semiconductor particles added to copper, gold or silver used in certain electrical purposes. It is also used in vulcanizing as secondary agent for rubber and as alloying agent of stainless steel, color glass and ceramics. Because of low melting point of tellurium it attracted attention and might have future uses including cancer, medicine and antibiotics.


Molecular methods used to identify the fungi while the shape and sizes produced by tellurium using dynamic light scattering. Tellurium is oval-shaped nanoparticles that are most likely corresponds to amine and carboxylic group. It also possesses a potential for antimicrobial activity that shows a promising results. Indeed, the antimicrobial activity of tellurium nanoparticles offers a novel and feasible methods for antibacterial multi-resistance problem. Therefore, fungal isolates Aspergillus welwitschiae contains tellurium nanoparticles and reveals good antibacterial activity against Escherichia coli and Staphylococcus aureus.


Source: Prepared by Joan Tura from Biotechnology Reports

Volume 18, June 2018, e00247