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Using a metagenomic sequencing approach on stool samples from children with Acute Flaccid Paralysis (AFP), we describe the genetic diversity of Sapoviruses (SaVs) in children in Nigeria. We identified six complete genome sequences and two partial genome sequences. Several SaV genogroups and genotypes were detected, including GII (GII.4 and GII.8), GIV (GIV.1), and GI (GI.2 and GI.7). To our knowledge, this is the first description of SaV infections and complete genomes from Nigeria. Pairwise identity and phylogenetic analysis showed that the Nigerian SaVs were related to previously documented gastroenteritis outbreaks with associated strains from China and Japan. Minor variations in the functional motifs of the nonstructural proteins NS3 and NS5 were seen in the Nigerian strains. To adequately understand the effect of such amino acid changes, a better understanding of the biological function of these proteins is vital. The identification of distinct SaVs reinforces the need for robust surveillance in acute gastroenteritis (AGE) and non-AGE cohorts to better understand SaVs genotype diversity, evolution, and its role in disease burden in Nigeria. Future studies in different populations are, therefore, recommended.

Termitomyces species are known edible mushrooms in Nigeria, believed to have exceptional culinary and nutraceutical properties. Methanol extract from fruiting bodies of Termitomyces robustus was evaluated for antidiabetic activity using in vitro α-amylase and α-glucosidase assays. The isolation and structural elucidation of metabolites from the T . robustus extract afforded five compounds including a new natural product γ-glutamyl-β-phenylethylamine 3 and four known phenyl derivatives: tryptophan 1 , 4-hydroxyphenylacetic acid 2 , 4-hydroxyphenylpropionic acid 4 , and phenyllactic acid 5 . Structures were elucidated from analyses of spectroscopic data (1   D and 2   D NMR, HRESIMS) and all isolated compounds were tested for α-amylase and α-glycosidase inhibitory activity. The in vitro assay established crude extract to possess α- amylase and α-glucosidase inhibition with IC 50 of 78.05   µg/mL and 86.10   µg/mL, respectively. The isolated compounds compared favourably with the standard drug, acarbose with IC 50 ranging from 6.18-15.08   µg/mL and 18.28-44.63   µg/mL for α-amylase and glucosidase, respectively.

Background: As frequent viral outbreaks continue to pose threat to public health, the unavailability of antiviral drugs and challenges associated with vaccine development underscore the need for antiviral drugs discovery in emergent moments (endemic or pandemic). Plants in response to microbial and pest attacks are able to produce defence molecules such as antimicrobial peptides as components of their innate immunity, which can be explored for viral therapeutics., Methods: In this study, partially purified peptide-rich fraction (P-PPf) were obtained from aqueous extracts of seven plants by reverse-phase solid-phase extraction and cysteine-rich peptides detected by a modified TLC method. The peptide-enriched fractions and the aqueous (crude polar) were screened for antiviral effect against three non-polio enterovirus species C members using cytopathic effect reduction assay., Results: In this study, peptide fraction obtained from Euphorbia hirta leaf showed most potent antiviral effect against Coxsackievirus A13, Coxsackievirus A20, and Enterovirus C99 (EV-C99) with IC 50  < 2.0 µg/mL and selective index ≥ 81. EV-C99 was susceptible to all partially purified peptide fractions except Allamanda blanchetii leaf., Conclusion: These findings establish the antiviral potentials of plants antimicrobial peptides and provides evidence for the anti-infective use of E. hirta in ethnomedicine. This study provides basis for further scientific investigation geared towards the isolation, characterization and mechanistic pharmacological study of the detected cysteine-rich peptides., (© 2021. The Author(s).)

The anti-enteroviral activity of three stilbenoids isolated from the leaves of Macaranga barteri was investigated using the cytopathic effect reduction assay. The stilbenes were inactive against echovirus E13 but showed activity against echoviruses E7 and E19. In particular, vedelianin ( 2 ), schweinfurthin G ( 3 ) and mappain ( 1 ) elicited antiviral activity on E19 with IC 50 values of 0.0036 nM, 0.018 nM and 0.24 µM, respectively. Vedelianin ( 2 ) showed the best selectivity profile amongst the isolated compounds with selectivity index values of 31 and 216 against E7 and E19, respectively. It is possible these compounds may be responsible for the traditional use of Macaranga barteri in the treatment of viral infections.

Background: Several Host defence peptides (HDPs) are low molecular weight (< 50 amino acids residues) peptides detected in several ethnomedicinal plants and have particularly gained research interest in recent times. Due to their wide range of bioactivity, occurrence, abundance and ability to induce very little resistance, they hold promising potentials in drug development. This study investigated the presence of bioactive peptides in the roots of Calliandra portoricensis (CPr) (Mimosaceae) and evaluated its antimicrobial activity against gram-negative and gram-positive bacteria., Methods: The crude peptide extract was obtained and pre-purified on pre-loaded tube of RP-C 18 solid phase cartridges (strata giga tube C18-E; 5 g, 20 mL, Phenomenex, Germany). Peptide enriched fraction was chemically analysed for arginine-rich/aromatic amino acid-rich peptides using a modified G-250 analytical stain and ninhydrin on thin layer chromatography (TLC) for a preliminary screening. Furthermore, MALDI TOF/TOF peptidomics was used to detect the presence and masses of the peptides. Extracts from CPr were used to test the ability to inhibit microbial growth using p-INT (Para-iodonitrotetrazolium violet) dye, with 0.1% gentamycin as positive control. The concentration that inhibits the growth of microorganisms by 50% (IC 50 ) were determined. Toxicity of the two extracts was accessed using freshly hatched nauplii of Artemia salina. Data analysis were evaluated using Microsoft excel and GraphPad Prism5., Results: Low molecular weight (LMW) peptides were detected in CPr using TLC and MALDI-TOF MS. Generally, the extracts exhibited good inhibition (70-95%) against the gram-negative and gram-positive bacteria, except MRSA6 typed strain. Enhanced activity was observed in the pre-purified peptide fraction than in the methanol crude, except on MRSA6. The greatest antimicrobial inhibition by pre-purified peptide fraction was against MRSA22 (IC 50  = 0.69 ± 0.33 μg/mL). The crude methanol extract (LC 50  = 5.13 μg/mL) was slightly more toxic than the peptide extract (LC 50  = 6.12 μg/mL)., Conclusions: This is the first report on detection of bioactive LMW peptides in Mimosaceae family. These peptides appear to be rich in arginine and aromatic amino acids. The peptide extract, in its pre-purified form showed a lower Brine shrimp cytotoxicity and an enhanced antimicrobial activity against the tested gram-negative and gram-positive bacteria.

Background: Echoviruses, a serotype of enteroviruses, infect millions of people globally and there is no specific drug treatment or vaccine available for its management. The screening of medicinal plants used locally for the treatment of infectious diseases, can provide a reliable option in the discovery of potent therapeutic compounds. This study was carried out to investigate the antiviral activities of 27 medicinal plant extracts, belonging to 26 different plant species, selected from Nigerian ethnobotany, against echovirus 7, 13 and 19 serotypes (E7, E13 and E19, respectively)., Methods: The plants were macerated in methanol and the cytotoxicities of the crude extracts were evaluated on the rhabdomyosarcoma cell line using the MTT assay. The antiviral activity of the plant extracts and fractions against echoviruses (E7, E13, and E19) was determined using the neutralisation assay, an assay that measures the inhibition of cytopathic effect on cell culture., Results: The crude extract of Macaranga barteri leaves had the highest cytotoxicity with CC 50 value of 0.27 μg/mL. This was followed by Crinum jagus (9.88 μg/mL) and Terminalia ivorensis (12.14 μg/mL). The antiviral screening showed that ten out of the 27 crude plant extracts tested were active on E7 and E19, inhibiting the cytopathic effect of the virus in tissue culture. None of the extracts inhibited the cytopathic effect caused by E13 serotype. Amongst the active plant extracts, the methanol extract of M. barteri leaves had the highest antiviral activity on both E7 and E9 with IC 50 values of 0.028 and 0.0017 ng/mL, respectively, followed by the Ageratum conyzoides extract (0.208 μg/mL, E7; 0.006 μg/mL, E19) and Mondia whitei extract (0.038 μg/mL, E7; 0.005 μg/mL, E19). Amongst the fractions of M. barteri, the DCM fraction was most the active and selective on E7 (IC 50  = 0.0075 ng/mL; SI = 19,896.54) and E19 (IC 50  = 0.0175 ng/mL; SI = 8581.24)., Conclusion: Our research has demonstrated that Macaranga barteri extracts has potent antiviral activity against echoviruses E7 and E19, and our findings suggest that this extract may have potential as a therapeutic agent in the treatment of enteroviral infections.