TARGETING THE MAIN PROTEASE AND THE SPIKE PROTEIN OF SARS-CoV-2 WITH NATURALLY OCCURRING COMPOUNDS FROM SOME CAMEROONIAN MEDICINAL PLANTS: AN IN-SILICO STUDY FOR DRUG DESIGNING

Despite the social distancing and hygiene rules prescribed by the WHO, the novel Corona-virus is still on the way of a significant rapid rise in deaths. Therefore, identification of chemotherapeutic drugs against Corona Viral Infection all around the world is still requires. Some medicinal plants have a valuable therapeutic effect when mixt with honey, the obtained formulations are preliminary use in Cameroon against viral infection particularly respiratory infections. In this work, we looked for the potential anti-SARS-CoV-2 molecule throw execution of in silico computational studies of six Cameroonian plants intervening in the treatment respiratory infections in apiphytotherapy. AutoDock Vina was used for docking studies against SARS-CoV-2 main protease (Mpro) and spike (SP) proteins. We further conducted of pharmacokinetics properties and the safety profile of compounds with the top score in order to identify the best drug candidates. Totally 100 compounds were screened, of these, eighteen showed high binding affinity against SARS-CoV-2 Mpro and SP. The results suggest the effectiveness of compounds 10 and 17 obtained from Citrus Sinensis as potent drugs against SARS-CoV-2 as they tightly bind to its Mpro and SP with low binding energies. The stability of the two compounds complexed with Mpro and SP was validated through MD simulation. The availability of potent protein inhibitors and diverse of compounds from Cameroon flora scaffolds indicate the feasibility of developing potent Mpro and SP proteins inhibitors as antivirals for COVID-19. Based on further in vivo and in vitro experiments and clinical trials, some of these phytoconstituents could be proposed for effective inhibition of the replication of the SARS-CoV-2.

Comparative investigation of toxicity induced by UV-A and UV-C radiation using Allium test.

Organisms are increasingly exposed to ultraviolet (UV) rays of sunlight, due to the thinning of the ozone layer and its widespread use in sterilization processes, especially against the SARS-CoV-2 virus. The present study was conducted with the purpose of evaluating the damages of UV-A and UV-C radiations in Allium cepa L. roots. The effects of two different types of UV on some physiological, biochemical, cytogenotoxic, and anatomical parameters were investigated in a multifaceted study. Three groups were formed from Allium bulbs, one of which was the control group. One of the other groups was exposed to 254 nm (UV-C) and the other to 365 nm (UV-A) UV. Growth retardation effect of UV was investigated with respect to germination percentage, total weight gain, and root elongation, while cytogenotoxicity arisen from UV exposure was analyzed using mitotic index (MI) and chromosomal aberration (CA) and micronucleus (MN) frequency. Oxidative stress due to UV application was investigated based on the accumulation of malondialdehyde (MDA) and the total activities of superoxide dismutase (SOD) and catalase (CAT) enzymes. Also, anatomical changes induced by UV-A and UV-C were analyzed in root meristematic cells. UV treatments caused significant reductions in growth-related parameters. Both UV treatments caused a significant increase in MDA levels and induction of SOD and CAT enzymes in root meristematic cells. A decrease in MI and an increase in the frequency of MN and CAs were observed in root tip cells, indicating the cytogenotoxic effect of UV application. Anatomical damages such as epidermis cell damage, cortex cell damage, necrotic zones, giant cell nucleus, and indistinct transmission tissue occurred in cells exposed to UV. All of the physiological, biochemical, cytogenetic, and anatomical damages observed in this study were more severe in cells treated with UV-C compared to UV-A. This study suggested that UV exposure triggered growth inhibition, cytogenotoxicity, oxidative stress, and meristematic cell damages in A. cepa roots depending on the wavelength.

Development of a Rapid UHPLC-PDA Method for the Simultaneous Quantification of Flavonol Contents in Onions (Allium cepa L.).

Onion, one of the most consumed vegetables in the world, is also known to contain high levels of antioxidant compounds, with protective effects against different degenerative pathologies. Specifically, onion is rich in flavonols, mainly quercetin derivatives, which are compounds with high antioxidant and free radical scavenging power. For this reason, it is of the utmost importance to count on optimal analytical methods that allow for the determination and quantification of these compounds of interest. A rapid ultra-high performance liquid chromatography (UHPLC)-photo-diode array (PDA) method for the separation of the major flavonols in onions was developed using a Box-Behnken design in conjunction with multiresponse optimization on the basis of the desirability function. The conditions that provided a successful separation were 9.9% and 53.2% of phase B at the beginning and at the end of the gradient, respectively; 55 °C column working temperature; and 0.6 mL min-1 flow rate. The complete separation was achieved in less than 2.7 min with excellent chromatographic characteristics. The method was validated, and its high precision, low detection and quantification limits, good linearity, and robustness were confirmed. The correct applicability of the method improves the analysis of the raw material, increasing the quality of onions and its subproducts in terms of bioactive compounds and functional characteristics for consumers.