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In this Research work, Silver Nanoparticles were green synthesized from Psidium guajava leaves<b> </b>and different Characterization techniques including UV-Visible, FT-IR, SEM and XRD were all employed to ascertain the absorption peaks, functional group, surface morphology and crystalline size of the nanoparticles respectively. These nanoparticles green synthesized were applied against four different pathogens namely, S. aureus (gram- positive bacteria), E. coli (gram- negative bacteria), C. albicans (gram- positive fungus) and Aspergillus niger and the investigation showed that the Silver nanoparticles synthesized were potent against the selected pathogens. From the UV-Vis spectral analysis, it was observed that highest absorption peaks appeared at 400nm and 500nm reflecting the surface plasmon resonance of silver Nanoparticles from guava leaves which is characteristic of Silver Nanoparticles. From the FT-IR spectrum of the sample under studied, the peaks 3416.85 cm^-1, 2923.51 cm^-1, 1618.95 cm^-1, 1384.49 cm^-1 and 1033.63 cm^-1 were observed where the absorption band at 3416.85 cm^-1corresponds to the stretching due to N-H, while the band at 2923.51 cm^-1 is associated with C-H stretch of alkane and O-H stretching. The peak at 1618.95 cm^-1 shows C=C stretching, 1384.49 cm^-1reveals the existence of C-H bending and 1033.63 cm^-1 depicted C-O stretching. The SEM analysis revealed the shape of the nanoparticles as being spherical while XRD result admits that the average size of the green synthesized Ag NPs was 45.5 nm using the Scherer’s formula. Augmentin was used as control at concentration of 300μg/L throughout antimicrobial studies. Different concentrations of 100, 200, 300, 400 and 500μg/L of Silver Nanoparticles were tested against each pathogen. It was discovered that with increase in concentrations of Silver Nanoparticles of all the pathogens, there generally appeared to be increase in inhibition zone. At higher concentration of 500μg/L, the zones of inhibition were in the following order; 22.50 mm, 17.00mm, 15.44mm, and 13.23mm for E. Coli, S. aureus, C. albicans and Aspergillus niger respectively. For each concentration investigated, E. coli, demonstrated higher zone of inhibition as opposed to all other pathogens investigated in this research.

In Central Africa, mushrooms are critically important non-timber forest products (NTFPs), both nutritionally and economically. A strain of edible and medicinal lignicolous fungus, <i>Pleurotus</i> tuber-regium (Rumph. ex Fr.) Singer 1951 (strain 190212), isolated from tissue (sclerotia), on PDA medium, was tested on corn grain and sawdust seedling substrates and on palm oil male inflorescence (<i>Elaeis guineensis</i> Jacq.), ground corn (<i>Zea mays</i> L) stalks and grass (<i>Paspalum notatum</i> L) soaked for 24 hrs then drained for 24 hours, and unsoaked ground corn (<i>Zea mays</i> L) stalks. The highest mycelial growth rate recorded was about 0.9 cm on the PDA medium; 5.97 cm on the corn-based seedling medium and 11.95 cm on the sawdust-based seedling medium. Total mycelial invasion on the PDA medium was observed on day 10, day 14 on the corn-based seedling medium, and day 24 on the sawdust-based seedling medium. The onset of mycelial invasion was noticeable on day 3 of seeding for all treatments T<SUB>0</SUB> (control), T<SUB>1</SUB> (Final substrate based on soaked ground corn stalks), T<SUB>2</SUB> (Final substrate based on unsoaked ground corn stalks), and T<SUB>3</SUB> (Final substrate based on turf). Total invasion of mycelium was obtained at day 15 of incubation for treatments T<SUB>1</SUB> and T<SUB>2</SUB>, at day 18 for treatment T3 and at day 24 for treatment T0. The results obtained on treatments T<SUB>1</SUB> and T<SUB>2</SUB> respectively (14.95±3.12% and 15.65±1.06%) of the maize stalk substrate, lead us to believe that the strain 190212 of <i>Pleurotus tuber-regium</i> species used has adapted and requires an improvement of the medium with nitrogen-rich additives such as soybean meal. This could achieve the theoretical yield of 20% or more, according to which a substrate can be considered better in producing sporophores.

Mucormycosis or black fungus although a rare fungal infection but has potential to be lethal and thus requires immediate treatment. The immune system is weakened due to SARS-CoV-2 and the body becomes susceptible and vulnerable to other infections as people are immune compromised. The immune system becomes weakened due to COVID-19 treatment especially in patients who are taking steroids making the body prone to attack by black fungus. As the black fungus cases are increasing in India, the country is facing shortage in medicaments in face of dual crisis. An epidemic of black fungus is sweeping India in the wake of a severe surge in COVID-19 cases. Experts are of the opinion that the cause is a combination of factors. These factors might include contaminated oxygen equipment and use of steroid drugs to treat certain COVID-19 patients.