SARS-CoV-2, the other face to SARS-CoV and MERS-CoV: Future predictions.

Coronavirus disease 2019 (COVID-19) outbreak is proving to be an unprecedented disaster that lays its dark shadow on global health, economics and personal freedom. Severe acute respiratory syndrome (SARS) and middle east respiratory syndrome (MERS) epidemics provide scientific data that is useful in better understanding and resolution of COVID-19. Similarities among SARS-CoV, MERS-CoV and SARS-CoV-2 have been investigated in the light of available data. SARS-CoV, MERS-CoV and SARS-CoV-2 evolved in bats and have positive-sense RNA genomes of 27.9 kb, 30.1 kb and 29.9 kb, respectively. Molecular and serological tools used for diagnosis of SARS and MERS patients resemble COVID-19 diagnostic tools. Stability and longevity data of SARS and MERS epidemics contribute in the current pandemic precaution policies. Trials to produce vaccines for SARS-CoV and MERS-CoV failed, therefore different strategies were employed for SARS-CoV2 vaccines production and during the past period antiviral agents, Convalescent plasma and monoclonal antibodies provide potential treatments for sever patients. The mortality rate caused by the SARS-CoV and MERS-CoV reached 15% and 37%, respectively. The first declarations about mortality rate of SARS-CoV-2 was around 2-4% but now this rate differed globally and reached more than 13% in some countries. A realistic COVID-19 outbreak scenario suggest that the pandemic might last for three years with fluctuation in the number of infected cases, unless vaccination process goes faster and/or antiviral drug is discovered.

GC/MS analysis of Juniperus procera extract and its activity with silver nanoparticles against Aspergillus flavus growth and aflatoxins production.

From ancient to currently, it has been hard to prevent the exposure to mycotoxigenic fungi, due to these fungi occurs naturally in the environment. This paper reports the antifungal activities of the Juniperus procera stem extract with silver nanoparticles (AgNPs) against Aspergillus flavus growth and aflatoxins production. Numerous constituents of J. procera extract were detected by GC/MS analysis. Methanolic extract at 30, 60 and 90 mg/mL inhibited the growth of A. flavus, where the inhibition reached to 50.86, 51.60 and 52.58 %. respectively while weak inhibition was observed using the aqueous extract. Growth of A. flavus was reduced using AgNPs, the highest inhibition 39.31 % was recorded at 100 ppm AgNPs. Synergistic activity was observed by applying 50 ppm of AgNPs with aqueous and methanolic extracts of J. procera . A reduction in aflatoxin B2 and G2 synthesis was observed using different concentrations of methanolic stems extract of J. procera particularly with AgNPs.