Phytoconstituents from Moringa oleifera fruits target ACE2 and open spike glycoprotein to combat SARS-CoV-2: An integrative phytochemical and computational approach

A comprehensive review of the phytochemicals, health benefits, pharmacological safety and medicinal prospects of Moringaoleifera

Moringa oleifera has emerged as a subject of increasing interest, drawing attention for its diverse phytochemical composition and potential health benefits. This review delves into Moringa oleifera's phytochemical constituents, including but not limited to flavonoids, alkaloids, and carotenoids. Expanding beyond its chemical intricacies, the spectrum of health advantages attributed to it are explored, encompassing its remarkable anticancer, antioxidant, anti-diabetic, anti-inflammatory, antimicrobial, and cardioprotective effect. Throughout this review, the underlying physiological mechanisms attributed to these properties by its phytochemicals are explored. Concurrently, the review addresses its pharmacological safety, ensuring a nuanced understanding of its applications in medicinal industries. In summary, this literature review presents a comprehensive exploration of Moringa oleifera, focusing on its phytochemical composition, health benefits, physiological mechanisms, pharmacological safety and nutritional importance.

Steroidal lactones from Withania somnifera effectively target Beta, Gamma, Delta and Omicron variants of SARS-CoV-2 and reveal a decreased susceptibility to viral infection and perpetuation: a polypharmacology approach

Prevention from disease is presently the cornerstone of the fight against COVID-19. With the rapid emergence of novel SARS-CoV-2 variants, there is an urgent need for novel or repurposed agents to strengthen and fortify the immune system. Existing vaccines induce several systemic and local side-effects that can lead to severe consequences. Moreover, elevated cytokines in COVID-19 patients with cancer as co-morbidity represent a significant bottleneck in disease prognosis and therapy. Withania somnifera (WS) and its phytoconstituent(s) have immense untapped immunomodulatory and therapeutic potential and the anticancer potential of WS is well documented. To this effect, WS methanolic extract (WSME) was characterized using HPLC. Withanolides were identified as the major phytoconstituents. In vitro cytotoxicity of WSME was determined against human breast MDA-MB-231 and normal Vero cells using MTT assay. WSME displayed potent cytotoxicity against MDA-MB-231 cells (IC50: 66 µg/mL) and no effect on Vero cells in the above range. MD simulations of Withanolide A with SARS-CoV-2 main protease and spike receptor-binding domain as well as Withanolide B with SARS-CoV spike glycoprotein and SARS-CoV-2 papain-like protease were performed using Schrödinger. Stability of complexes followed the order 6M0J-Withanolide A > 6W9C-Withnaolide B > 5WRG-Withanolide B > 6LU7-Withanolide A. Maximum stable interaction(s) were observed between Withanolides A and B with SARS-CoV-2 and SARS-CoV spike glycoproteins, respectively. Withanolides A and B also displayed potent binding to pro-inflammatory markers viz. serum ferritin and IL-6. Thus, WS phytoconstituents have the potential to be tested further in vitro and in vivo as novel antiviral agents against COVID-19 patients having cancer as a co-morbidity.

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Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-023-00184-y.

In Silico Exploration of Potential Phytoconstituents from the Bark Extract of Boswellia serrata for Hemorrhoidal Disease: Molecular Docking and Molecular Dynamics Analysis

Boswellia serrata Roxb. Ex Colebr is a popular medicinal plant used traditionally in herbal medicinal preparations to treat a variety of diseases. The purpose of the present investigation was to investigate the anti-hemorrhoidal property of the bark extract of B. serrata (BS). For this, the sequential Soxhlet extraction method was carried out by using different solvents such as hexane, chloroform, and methanol. After the extraction, the obtained dry extracts were tested for quantitative determinations such as total alkaloid content (TAC), total flavonoid content (TFC), total phenol content (TPC), and total tannin content (TTC) for all the extracts. Moreover, in vitro antioxidant activity was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and scavenging activity against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS). Methanolic bark extract showed the highest TPC (67.10±1.83), TFC (372.73±4.45), TAC (9.732±1.06), and TTC (48.932±1.82), as well as the antioxidant assays DPPH (IC50=9.88 μg/ml) and ABTS (IC50=15.09 μg/ml). In this study, both LC-MS and GC-MS were performed to identify the chemical composition of all the extracts. Consequently, 19 compounds were identified by GC-MS and 27 compounds were identified by LC-MS analysis. The identified phytoconstituent(s) that could potentially interact with the target protein cyclooxygenase-2 (COX-2) (PDB: 4RRW) using molecular dynamics simulation and in silico docking were studied. Three compounds that have passed in drug-likeness and ADME-Tox properties are having more docking score than the standard. In this study, camptothecin, justicidin B, and taxiphyllin are identified as potential lead compounds with anti-hemorrhoidal properties and may be helpful in the process of drug development and discovery of novel drugs. Hence, these results demonstrate that BS is a good source of pharmacologically active components with potential applications against hemorrhoidal disease.

A Comprehensive Update of Various Attempts by Medicinal Chemists to Combat COVID-19 through Natural Products

The ongoing COVID-19 pandemic has resulted in a global panic because of its continual evolution and recurring spikes. This serious malignancy is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the outbreak, millions of people have been affected from December 2019 till now, which has led to a great surge in finding treatments. Despite trying to handle the pandemic with the repurposing of some drugs, such as chloroquine, hydroxychloroquine, remdesivir, lopinavir, ivermectin, etc., against COVID-19, the SARS-CoV-2 virus continues its out-of-control spread. There is a dire need to identify a new regimen of natural products to combat the deadly viral disease. This article deals with the literature reports to date of natural products showing inhibitory activity towards SARS-CoV-2 through different approaches, such as in vivo, in vitro, and in silico studies. Natural compounds targeting the proteins of SARS-CoV-2-the main protease (M^pro), papain-like protease (PL^pro), spike proteins, RNA-dependent RNA polymerase (RdRp), endoribonuclease, exoribonuclease, helicase, nucleocapsid, methyltransferase, adeno diphosphate (ADP) phosphatase, other nonstructural proteins, and envelope proteins-were extracted mainly from plants, and some were isolated from bacteria, algae, fungi, and a few marine organisms.

Antiviral Molecular Targets of Essential Oils against SARS-CoV-2: A Systematic Review

Essential oils are potential therapeutics for coronavirus disease 2019 (COVID-19), in which some of the volatile compounds of essential oils have been well known for their broad antiviral activities. These therapeutic candidates have been shown to regulate the excessive secretion of pro-inflammatory cytokines, which underlies the pathogenesis of severe COVID-19. We aimed to identify molecular targets of essential oils in disrupting the cell entry and replication of SARS-CoV-2, hence being active as antivirals. Literature searches were performed on PubMed, Scopus, Scillit, and CaPlus/SciFinder (7 December 2022) with a truncated title implying the anti-SARS-CoV-2 activity of essential oil. Data were collected from the eligible studies and described narratively. Quality appraisal was performed on the included studies. A total of eight studies were included in this review; four of which used enzyme inhibition assay, one—pseudo-SARS-CoV-2 culture; two—whole SARS-CoV-2 culture; and one—ACE2-expressing cancer cells. Essential oils may prevent the SARS-CoV-2 infection by targeting its receptors on the cells (ACE2 and TMPRSS2). Menthol, 1,8-cineole, and camphor are among the volatile compounds which serve as potential ACE2 blockers. β-caryophyllene may selectively target the SARS-CoV-2 spike protein and inhibit viral entry. Other interactions with SARS-CoV-2 proteases and RdRp are observed based on molecular docking. In conclusion, essential oils could target proteins related to the SARS-CoV-2 entry and replication. Further studies with improved and uniform study designs should be carried out to optimize essential oils as COVID-19 therapies.

Synthesis and Biological Activity Characterization of Novel 5-Oxopyrrolidine Derivatives with Promising Anticancer and Antimicrobial Activity

The 1-(4-acetamidophenyl)-5-oxopyrrolidine carboxylic acid was applied for synthesizing derivatives bearing azole, diazole, and hydrazone moieties in the molecule. Modification of an acetamide fragment to the free amino group afforded compounds with two functional groups, which enabled to provide a series of 4-substituted-1-(4-substituted phenyl)pyrrolidine-2-ones. The resulted compounds 2 and 4-22 were subjected to the in vitro anticancer and antimicrobial activity determination. The compounds 18-22 exerted the most potent anticancer activity against A549 cells. Furthermore, compound 21 bearing 5-nitrothiophene substituents demonstrated promising and selective antimicrobial activity against multidrug-resistant Staphylococcus aureus strains, including linezolid and tedizolid-resistant S. aureus. These results demonstrate that 5-oxopyrolidine derivatives are attractive scaffolds for the further development of anticancer and antimicrobial compounds targeting multidrug-resistant Gram-positive pathogens.