Exploring antioxidative, cytotoxic and neuropharmacological insights into Bixa orellana leaves: Experimental and in silico approaches.

Background Study: The aim of this research was to examine possible antioxidant, cytotoxic and neurological activity of methanol and n-hexane extracts of Bixa orellana leaves. Additionally, we aimed to identify potential lead compounds through in-silico analysis. Methods: In-vitro antioxidative properties were investigated through different assays, including: total phenolic content assay (TPC), total flavonoid content assay (TFC), DPPH free radical scavenging assay and reducing power assay. Also, the cytotoxic effect of the samples was assessed using the brine shrimp lethality test. In addition, anxiolytic, locomotor, and CNS depressant activities were assessed utilizing various established methods. Moreover, reported compounds were used in the in silico study to explore the best-fit phytoconstituents against gamma-aminobutyric acid (GABAA) receptor. Results: MBOL displayed substantial antioxidative activities in various established assays compared to NBOL. In brine shrimp lethality bioassay, both MBOL and NBOL revealed cytotoxic activity in a concentration-dependent approach. Again, in Elevated Plus Maze test, 200 and 400 mg/kg of NBOL and MBOL demonstrated significant anxiolytic activities evident from time spent in open arms. In addition, maximum number of head dipping was demonstrated by MBOL at 400 mg/kg (53.90 ± 1.16) in Hole Board test. NBOL and MBOL at both doses significantly diminished the magnitude of movements from the 2nd to 5th observation periods in Open Field test. Furthermore, in Hole Cross test, MBOL remarkably dwindled the locomotor activity at 120 min and 180 min (3.60 ± 0.40 and 2.40 ± 0.51) at 400 mg/kg. Finally, in silico analysis revealed 13 compounds as promising leads with strong binding affinity to GABAA receptor along with good pharmacokinetics and toxicity profiles. Conclusion: Therefore, the present study's findings advocate the traditional usage of this plant and recommend both MBOL and NBOL as as a potential source of therapeutic candidate for the management of neurological disorders.

Therapeutic role of traditionally used Indian medicinal plants and spices in combating COVID-19 pandemic situation.

The coronavirus disease (COVID-19) caused by SARS-CoV-2 is a big challenge and burning issue to the scientific community and doctors worldwide. Globally, COVID-19 has created a health disaster and adversely affects the economic growth. Although some vaccines have already emerged, no therapeutic medication has yet been approved by FDA for the treatment of COVID-19 patients. Traditionally, we have been using different medicinal plants like neem, tulsi, tea, and many spices like garlic, ginger, turmeric, black seed, onion, etc. for the treatment of flu-like diseases. In this paper, we are highlighting the recent research progress in the identification of natural products from the Indian medicinal plants and spices that have potential inhibition properties against SARS-CoV-2. This study will provide an initiative to stimulate further research by providing useful guidance to the medicinal chemists for designing new protease inhibitors effective against SARS-CoV-2 in future.Communicated by Ramaswamy H. Sarma.

Quantification of cucurbitacin E in different varieties of melon (Cucumis melo L.) fruit through validated RP-HPLC method.

The different varieties of melons (Cucumis melo L.) have been used in various traditional systems of medicine for decades to treat different ailments, including inflammation, cancer, cardiovascular, diabetes, edema, etc. The present study was designed for the quantification of cucurbitacin E in five different varieties of melon fruit through a validated RP-HPLC method. A solvent system is being optimized with a 70:30 (v/v) ratio of acetonitrile: water (1% glacial acetic acid) at a 1 mL/min flow rate and scanning spectrum (λmax) of 230 nm. A calibration curve for standard cucurbitacin E was generated and found to be linear (1-100 µg/mL). The variation of cucurbitacin E content among five different varieties of melon fruits is 0.0129% w/w- 0.231% w/w. This precise and reproducible method may be beneficial in addressing the quality-related aspects of medicinal food plants of Cucurbitaceae and its derived products or formulations.

Role of medicinal plants in inhibiting SARS-CoV-2 and in the management of post-COVID-19 complications.

BACKGROUND: The worldwide corona virus disease outbreak, generally known as COVID-19 pandemic outbreak resulted in a major health crisis globally. The morbidity and transmission modality of COVID-19 appear more severe and uncontrollable. The respiratory failure and following cardiovascular complications are the main pathophysiology of this deadly disease. Several therapeutic strategies are put forward for the development of safe and effective treatment against SARS-CoV-2 virus from the pharmacological view point but till date there are no specific treatment regimen developed for this viral infection. PURPOSE: The present review emphasizes the role of herbs and herbs-derived secondary metabolites in inhibiting SARS-CoV-2 virus and also for the management of post-COVID-19 related complications. This approach will foster and ensure the safeguards of using medicinal plant resources to support the healthcare system. Plant-derived phytochemicals have already been reported to prevent the viral infection and to overcome the post-COVID complications like parkinsonism, kidney and heart failure, liver and lungs injury and mental problems. In this review, we explored mechanistic approaches of herbal medicines and their phytocomponenets as antiviral and post-COVID complications by modulating the immunological and inflammatory states. STUDY DESIGN: Studies related to diagnosis and treatment guidelines issued for COVID-19 by different traditional system of medicine were included. The information was gathered from pharmacological or non-pharmacological interventions approaches. The gathered information sorted based on therapeutic application of herbs and their components against SARSCoV-2 and COVID-19 related complications. METHODS: A systemic search of published literature was conducted from 2003 to 2021 using different literature database like Google Scholar, PubMed, Science Direct, Scopus and Web of Science to emphasize relevant articles on medicinal plants against SARS-CoV-2 viral infection and Post-COVID related complications. RESULTS: Collected published literature from 2003 onwards yielded with total 625 articles, from more than 18 countries. Among these 625 articles, more than 95 medicinal plants and 25 active phytomolecules belong to 48 plant families. Reports on the therapeutic activity of the medicinal plants belong to the Lamiaceae family (11 reports), which was found to be maximum reported from 4 different countries including India, China, Australia, and Morocco. Other reports on the medicinal plant of Asteraceae (7 reports), Fabaceae (8 reports), Piperaceae (3 reports), Zingiberaceae (3 reports), Ranunculaceae (3 reports), Meliaceae (4 reports) were found, which can be explored for the development of safe and efficacious products targeting COVID-19. CONCLUSION: Keeping in mind that the natural alternatives are in the priority for the management and prevention of the COVID-19, the present review may help to develop an alternative approach for the management of COVID-19 viral infection and post-COVID complications from a mechanistic point of view.

Identification of potential edible mushroom as SARS-CoV-2 main protease inhibitor using rational drug designing approach.

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is highly pathogenic to humans and has created health care threats worldwide. This urgent situation has focused the researchers worldwide towards the development of novel vaccine or small molecule therapeutics for SARS-CoV-2. Although several vaccines have already been discovered and are in use for the masses, no therapeutic medication has yet been approved by FDA for the treatment of COVID-19. Keeping this in view, in the present study, we have identified promising hits against the main protease (Mpro) of SARS-CoV-2 from edible mushrooms. Structure-based virtual screening (VS) of 2433 compounds derived from mushrooms was performed with Mpro protein (6LU7). Four promising hits, namely, Kynapcin-12 (M_78), Kynapcin-28 (M_82), Kynapcin-24 (M_83), and Neonambiterphenyls-A (M_366) were identified based on the result of docking, Lipinski's rule, 100 ns molecular dynamics (MD) simulation and MM/PBSA binding free energy calculations. Finally, the inhibitory properties of these hits were compared with three known inhibitors, baicalein (1), baicalin (2), and biflavonoid (3). Data indicated that M_78, M_82 and M_83 compounds present in edible mushroom Polyozellus multiplex were potent inhibitors of Mproprotein (6LU7). It could be concluded that edible mushroom Polyozellus multiplex has potential activity against SARS-CoV-2 infection and identified molecules could be further explored as therapeutic inhibitors against SARS-CoV-2.

Bioactive compounds and functional properties of Rambai (Baccaurea motleyana Müll. Arg.) fruit: A comprehensive review.

Rambai (Baccaurea motleyana Müll. Arg.), a member of the Phyllanthaceae family, is one of the underutilized fruits native to Indonesia, Malaya Peninsula, and Thailand. Nowadays, B. motleyana is cultivated for its fruits in many parts of Northern Australia, China, and Southeast Asia. The edible part of the fruit is white and contains reddish arillodes that taste sweet to acid-sweet. The ripe fruit is consumed fresh and can be processed into juice, jams, organic vinegar, and wine. Traditionally, the fruit and its bark are used to treat stomach and eye diseases, respectively. The fruits of B. motleyana are a good source of vitamins, minerals, and fibers, and they also contain bioactive compounds such as phenolic acids, flavonoids, carotenoids, and terpenes. This scientific review describes the nutritional composition, phytochemistry, and pharmacology of B. motleyana. In addition, most recent information is provided to promote the widespread consumption of B. motleyana fruit as well as to create research interest on this interesting species among the scientific community.

Identification of potential inhibitors of SARS-CoV-2 main protease and spike receptor from 10 important spices through structure-based virtual screening and molecular dynamic study.

The outbreak of novel coronavirus disease (COVID-19) caused by SARS-CoV-2 poses a serious threat to human health and world economic activity. There is no specific drug for the treatment of COVID-19 patients at this moment. Traditionally, people have been using spices like ginger, fenugreek and onion, etc. for the remedy of a common cold. This work identifies the potential inhibitors of the main protease (Mpro) and spike (S) receptor of SARS-CoV-2 from 10 readily available spices. These two proteins, S and Mpro, play an important role during the virus entry into the host cell, and replication and transcription processes of the virus, respectively. To identify potential molecules an in-house databank containing 1040 compounds was built-up from the selected spices. Structure-based virtual screening of this databank was performed with two important SARS-CoV-2 proteins using Glide. Top hits resulted from virtual screening (VS) were subjected to molecular docking using AutoDock 4.2 and AutoDock Vina to eliminate false positives. The top six hits against Mpro and top five hits against spike receptor subjected to 130 ns molecular dynamic simulation using GROMACS. Finally, the compound 1-, 2-, 3- and 5-Mpro complexes, and compound 17-, 18-, 19-, 20- and 21- spike receptor complexes showed stability throughout the simulation time. The ADME values also supported the drug-like nature of the selected hits. These nine compounds are available in onion, garlic, ginger, peppermint, chili and fenugreek. All the spices are edible and might be used as home remedies against COVID-19 after proper biological evaluation.

Potentiality of Moringa oleifera against SARS-CoV-2: identified by a rational computer aided drug design method.

Coronavirus disease 2019 (COVID-19) has created a global human health crisis and economic setbacks. Lack of specific therapeutics and limited treatment options against COVID-19 has become a new challenge to identify potential hits in order to develop new therapeutics. One of the crucial life cycle enzymes of SARS-CoV-2 is main protease (Mpro), which plays a major role in mediating viral replication, makes it an attractive drug target. Virtual screening and three times repeated 100 ns molecular dynamics simulation of the best hits were performed to identify potential SARS-CoV-2 Mpro inhibitors from the available compounds of an antiviral plant Moringa oleifera. Three flavonoids isorhamnetin (1), kaempferol (2) and apigenin (3) showed good binding affinity, stable protein-ligand complexes throughout the simulation time, high binding energy and similar binding poses in comparison with known SARS-CoV-2 Mpro inhibitor baicalein. Therefore, different parts of M. oleifera may be emerged as a potential preventive and therapeutic against COVID-19.

Identification of SARS-CoV-2 Main Protease Inhibitors Using Structure Based Virtual Screening and Molecular Dynamics Simulation of DrugBank Database.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is highly pathogenic to humans and has created an unprecedented global health care threat. Globally, intense efforts are going on to discover a vaccine or new drug molecules to control the COVID-19. However, till today, there is no effective therapeutics or treatment available for COVID-19. In this study, we aim to find out potential small molecule inhibitors for SARS-CoV-2 main protease (Mpro) from the known DrugBank database version 5.1.8. We applied structure-based virtual screening of the database containing 11875 numbers of drug candidates to identify potential hits for SARS-CoV-2 Mpro inhibitors. Seven potential inhibitors having admirable XP glide score ranging from -15.071 to -8.704 kcal/mol and good binding affinity with the active sites amino acids of Mpro were identified. The selected hits were further analyzed with 50 ns molecular dynamics (MD) simulation to examine the stability of protein-ligand complexes. The root mean square deviation and potential energy plot indicates the stability of the complexes during the 50 ns MD simulation. The MM-GBSA analysis also showed good binding energy of the selected hits (-83.2718 to -58.6618 kcal/mol). Further analysis revealed critical hydrogen bonds and hydrophobic interactions between compounds and the target protein. The compounds bind to biologically important regions of Mpro, indicating their potential to inhibit the functionality of this component.

In Silico Identification of Potential Inhibitors of ADP-Ribose Phosphatase of SARS-CoV-2 nsP3 by Combining E-Pharmacophore- and Receptor-Based Virtual Screening of Database.

The recently emerged 2019 Novel Coronavirus (SARS-CoV-2) and associated COVID-19 disease cause serious or even fatal respiratory tract infection. Observing the spread, illness and death caused by COVID-19, the World Health Organization (WHO) declared COVID-19 a pandemic. To date, there is no approved therapeutics or effective treatment available to combat the outbreak. This urgent situation is pressing the world to respond with development of novel vaccine or a small molecule therapeutics for SARS-CoV-2. In line with these efforts, the structure of several proteins of SARS-CoV-2 has been rapidly resolved and made publicly available to facilitate global efforts to develop novel drug candidates. In this paper, we aim to find out the small molecule inhibitors for ADP-ribose phosphatase of SARS-CoV-2. In order to identify potential inhibitors, we applied sequential E-pharmacophore and structure-based virtual screening (VS) of MolPort database containing 113687 number of commercially available natural compounds using Glide module. Six potential inhibitors having admirable XP glide score range from -11.009 to -14.684 kcal/mol and good binding affinity towards active sites were identified. All the molecules are commercially available for further characterization and development by scientific community. The in vitro activity of selected inhibitors can be done easily which will provide useful information for clinical treatment of novel coronavirus pneumonia.

TBHP-mediated oxidative synthesis of substituted pyrimido[4,5-d]pyrimidines from N-uracil amidines and methylarenes under metal free conditions.

An efficient and operationally simple protocol has been demonstrated for the synthesis of 1,3,5,7-tetrasubstituted pyrimido[4,5-d]pyrimidines via TBHP-mediated direct oxidative coupling of N-uracil amidines and methylarenes under metal-free conditions. Due to the inherent stability of methylarenes compared to aldehydes, the presented synthetic protocol is adaptable to a broad substrate scope, is operationally simple, has no need for stringent protection in the whole preparation process, and has the potential to prepare valuable products that are currently inaccessible or challenging to prepare using conventional methods. It is a significantly important complement to the conventional synthetic methods. The reaction possesses an efficient tandem oxidation-imination-cyclization process.