Investigation of cgrA and cyp51A gene alternations in Aspergillus fumigatus strains exposed to kombucha fermented tea

Chemical Composition and Antifungal and Antibiofilm Effects of Vitex pseudo-negundo Essential Oil against Pathogenic Fungal Strains

Background

Vitex pseudo-negundo is a plant of the Lamiaceae family that grows in different parts of the world and the vicinity of seasonal rivers in Iran.

Methods

The chemical composition of the Vitex pseudo-negundo essential oils was distilled and evaluated using gas chromatography/mass spectrometry. The antifungal activity of the essential oils against the fungal strains was analyzed by broth microdilution methods as suggested by the Clinical and Laboratory Standards Institute. Furthermore, the antibiofilm activity of the Vitex pseudo-negundo essential oils was assessed using the XTT reduction assay.

Results

Based on GC/MS analysis, the major components of the Vitex pseudo-negundo essential oils were α-pinene, α-terpinyl acetate, limonene, and (E)-caryophyllene. The growth of tested yeasts was inhibited at concentrations ranging from 2 to 64 μl/mL. Vitex pseudo-negundo fruit essential oil was the most effective in inhibiting yeast growth. Moreover, the essential oils exhibited antifungal activity against filamentous fungi strains. Additionally, the biofilm formation of Candida albicans was inhibited by the leaf, flower, and fruit of the essential oils.

Conclusion

Considering the significant antifungal activities of these essential oils, they can be considered a potential source for formulating novel agents to control fungal infections.

Advances in Kombucha Tea Fermentation: A Review

Kombucha is a carbonated, slightly acidic beverage traditionally produced by the fermentation of sweetened tea by a symbiotic culture of bacteria and yeast (SCOBY). The microbial community of kombucha is a complex one, whose dynamics are still not fully understood; however, the emergence of culture-independent techniques has allowed a more comprehensive insight into kombucha microbiota. In recent times, advancements have been made towards the optimisation of the fermentation process, including the use of alternative substrates, defined starter cultures and the modification of fermentation parameters, with the aim of producing an innovative beverage that is improved in terms of its physiochemical, sensory and bioactive properties. The global kombucha market is rapidly increasing, with the rising popularity of the tea attributed in part to its purported health benefits, despite the lack of research in human subjects to substantiate such claims. Accordingly, the incidence of kombucha home-brewing has increased, meaning there is a requirement for individuals to recognise the potential hazards associated with fermentation and the relevant preventative measures to be undertaken to ensure the safe preparation of kombucha. The aim of this review is to provide an update regarding the current knowledge of kombucha production, microbiology, safety and marketing.

Current Practices for Reference Gene Selection in RT-qPCR of Aspergillus: Outlook and Recommendations for the Future

Aspergillus is a genus of filamentous fungi with vast geographic and ecological distributions. Species within this genus are clinically, agriculturally and biotechnologically relevant, leading to increasing interest in elucidating gene expression dynamics of key metabolic and physiological processes. Reverse-transcription quantitative Polymerase Chain Reaction (RT-qPCR) is a sensitive and specific method of quantifying gene expression. A crucial step for comparing RT-qPCR results between strains and experimental conditions is normalisation to experimentally validated reference gene(s). In this review, we provide a critical analysis of current reference gene selection and validation practices for RT-qPCR gene expression analyses of Aspergillus. Of 90 primary research articles obtained through our PubMed query, 17 experimentally validated the reference gene(s) used. Twenty reference genes were used across the 90 studies, with beta-tubulin being the most used reference gene, followed by actin, 18S rRNA and glyceraldehyde 3-phosphate dehydrogenase. Sixteen of the 90 studies used multiple reference genes for normalisation. Failing to experimentally validate the stability of reference genes can lead to conflicting results, as was the case for four studies. Overall, our review highlights the need to experimentally validate reference genes in RT-qPCR studies of Aspergillus.

Recent Progress in Chemical Composition, Production, and Pharmaceutical Effects of Kombucha Beverage: A Complementary and Alternative Medicine

Kombucha is a valuable traditional natural tea that contains beneficial compounds like organic acids, minerals, different vitamins, proteins, polyphenols, and several anions. Kombucha possesses anticancer, antioxidant, antimicrobial, and antifungal activity as well as hepatoprotective effects. Considering the unique properties of Kombucha, several investigations have already been conducted on its nutritional properties. In this review, an effort has been devoted to pool recent literature on the biomedical application of Kombucha under the objectives, including the chemical composition of Kombucha and industrial production, and highlight different properties of Kombucha. Finally, we explain its adverse effects and prospect. This review is an active, in-depth, and inclusive report about Kombucha and its health benefits.