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Light influences important physiological and morphological responses in fungi, hence they can sense near UV, blue, green, red and far-red lights using up to eleven (11) photoreceptors and signaling cascades to control a larger proportion of the genomes and adapt to environmental factors. Though light is an environmental signal regulating myriad of biological processes, fungi do not utilize it as a source of energy for synthesis of food but for information and other developmental processes. Two genes WC-1 and WC-2 have been identified to function as photoreceptor for blue light proteins or orthologs and transcription factor for other light induced phenomenon. Additionally, conserved WCC photoreceptor orthologs (FaWC1 and FaWC2) may also perform divergent roles in some fungal species such as light signals to regulate UV resistance, secondary metabolism and sexual reproduction as well as for virulent expression. Response to white light irradiation has also elicited different morphological and physiological changes in various species of fungi such as asexual reproduction and induction or inhibition of several developmental processes. Mushrooms also requires light for developmental processes such as the asexual stage for completion of its life cycle whereas it is unnecessary at the vegetative stage. This review provides some recent crucial impact of light irradiation on the developmental processes of fungi such as sporogenesis, germination/conidiation, reproductive development, pathogenesis, mycotoxin and mushroom development even though they are generally known to be achlorophyllous and non-photosynthetic. Thus, identifying conditions of light regime that will favour fungal development with reduced mycotoxin production will be beneficial to animals and human health. Additionally, developing new techniques to control fungal species may lead to the development of faster and more effective food-processing methods.

Profilistic study of bioactivities of aqueous, ethanolic and methanolic leaf extracts of Gongronema latifolium in combination with potassium aluminium sulphate (Alum) against some clinical bacterial pathogens were investigated by disc diffusion (DD) and Agar well diffusion (AWD) methods respectively. The leaf extracts at concentrations of 0.1-0.3g were reconstituted in sterile distilled water as well as 1.0-3.0g of alum prior to application. In-vitro bioactivity of various concentrations of the extracts and in combination with alum were evaluated by measuring diameter of inhibition zones (DIZs) respectively. Methanolic leaf extract (MLE) had the largest mean DIZs of 14.5±0.5 and 11.5±0.0mm on Escherichia coli and Salmonella typhi, with enhanced bioactivity of 19.5±0.7 and 17.5±0.7mm with alum against Bacillus subtilis, Sal. typhi and Pseudomonas aeruginosa by DD and AWD methods respectively. However, aqueous leaf extract (ALE) and ethanolic leaf extract (ELE) and their combinations depicted appreciable antibacterial activity on the pathogens but incomparable to MLE. Generally, there was enhancement of bioactivties with the incorporation of Alum to the leaf extracts (irrespective of solvent of extraction) on a dose response fashion particularly by AWD method. Furthermore, the low MIC values of <0.05 to 0.2mg/ml on the bacteria with MLE and ALE, validates their potency and broad spectrum activity. In contrast, the very large DIZs of Ciprofloxacin (CP) reflects the beneficial impact of purified chemotherapeutics against pathogens. Thus, the improved efficacy of these extracts with alum would justify future application in ethnomedicine as well as in nutraceuticals/pharmaceuticals or in food systems as “green chemicals” or “biopreservatives”.International Current Pharmaceutical Journal, October 2018, 6(12): 92-98

Increase in yield of tropical grasses viz. digit grass (Digitaria decumbens), guinea grass (Panicum maximum) and pearl millet (Penisetum americanum) inoculated with tropical nitrogen-fixing bacterium, Spirillum lipoferum was investigated. The study was carried out for three consecutive years (2016-2018). Dry matter yields and protein content of the three tropical grasses were used for the assessment. In 2017, pearl millet (Penisetum americanum) and guinea grass (Panicum maximum) produced significantly higher protein content and dry matter yields. Projected yields using regression analysis of both pearl millet and guinea grass indicated that about 40kgN ha-1 yr-1 were replaced by inoculation. Although, protein production of guinea grass was lower during 2018, dry matter yield responses were similar to those of 2017. This research has shown that inoculation with Spirillum lipoferum, a tropical nitrogen-fixing bacterium reduced acetylene and increased yields or reduced nitrogen fertilizer requirement of the tropical grasses as well as replacement of up to 40KgN ha-1. This amount is agro-economically important and suggests the viability and potential for grass-bacteria systems.