Identification of Flavonoids from Scutellaria barbata D. Don as Inhibitors of HIV-1 and Cathepsin L Proteases and Their Structure-Activity Relationships.

Scutellaria barbata D. Don (SB, Chinese: Ban Zhi Lian), a well-known medicinal plant used in traditional Chinese medicine, is rich in flavonoids. It possesses antitumor, anti-inflammatory, and antiviral activities. In this study, we evaluated the inhibitory activities of SB extracts and its active components against HIV-1 protease (HIV-1 PR) and SARS-CoV2 viral cathepsin L protease (Cat L PR). UPLC/HRMS was used to identify and quantify the major active flavonoids in different SB extracts, and fluorescence resonance energy transfer (FRET) assays were used to determine HIV-1 PR and Cat L PR inhibitions and identify structure-activity relationships. Molecular docking was also performed, to explore the diversification in bonding patterns of the active flavonoids upon binding to the two PRs. Three SB extracts (SBW, SB30, and SB60) and nine flavonoids inhibited HIV-1 PR with an IC50 range from 0.006 to 0.83 mg/mL. Six of the flavonoids showed 10~37.6% inhibition of Cat L PR at a concentration of 0.1 mg/mL. The results showed that the introduction of the 4'-hydroxyl and 6-hydroxyl/methoxy groups was essential in the 5,6,7-trihydroxyl and 5,7,4'-trihydroxyl flavones, respectively, to enhance their dual anti-PR activities. Hence, the 5,6,7,4'-tetrahydroxyl flavone scutellarein (HIV-1 PR, IC50 = 0.068 mg/mL; Cat L PR, IC50 = 0.43 mg/mL) may serve as a lead compound to develop more effective dual protease inhibitors. The 5,7,3',4'-tetrahydroxyl flavone luteolin also showed a potent and selective inhibition of HIV-1 PR (IC50 = 0.039 mg/mL).

The Controversial Roles of Areca Nut: Medicine or Toxin?

Areca nut (AN) is used for traditional herbal medicine and social activities in several countries. It was used as early as about A.D. 25-220 as a remedy. Traditionally, AN was applied for several medicinal functions. However, it was also reported to have toxicological effects. In this review article, we updated recent trends of research in addition to acquire new knowledge about AN. First, the history of AN usage from ancient years was described. Then, the chemical components of AN and their biological functions was compared; arecoline is an especially important compound in AN. AN extract has different effects caused by different components. Thus, the dual effects of AN with pharmacological and toxicological effects were summarized. Finally, we described perspectives, trends and challenges of AN. It will provide the insight of removing or modifying the toxic compounds of AN extractions for enhancing their pharmacological activity to treat several diseases in future applications.

Studies on the Catechin Constituents of Bark of Cinnamomum sieboldii.

Screening for bioactivity related to anti-infective, anti-methicillin-resistant Staphylococcus aureus (MRSA) and anti-viral activity, led us to identify active compounds from a methanol extract of Litsea japonica (Thub.) Juss. and the hot water extract of bark of Cinnamomum sieboldii Meisn (also known as Karaki or Okinawa cinnamon). The two main components in these extracts were identified as the catechin trimers (+)-cinnamtannin B1 and pavetannin B5. Moreover, these extracts exhibited anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) activity. The structures of these catechin trimers were previously determined by chemical and spectroscopic methods. Pavetanin B5 has never been reported to be isolated as a pure form and has been obtained as a mixture with another component. Although other groups have reported the putative structure of pavetannin B5, preparation of the methylated derivative of pavetannin B5 in this study allowed us to obtain the pure form for the first time as the undecamethyl derivative and confirm its exact structure. Commercially available (+)-cinnamtannin B1 and aesculitannin B (C2'-epimer of cinnamtannin B1) both of which contained pavetannin B5 as a minor component, and C. sieboldii bark extract (approx. 5/2 mixture of (+)-cinnamtannin B1/pavetannin B5) were assessed for anti-SARS-CoV-2 activity. Both C. sieboldii bark extract and commercially available aesculitannin B showed viral growth inhibitory activity.

Elderberry Extracts: Characterization of the Polyphenolic Chemical Composition, Quality Consistency, Safety, Adulteration, and Attenuation of Oxidative Stress- and Inflammation-Induced Health Disorders.

Elderberry is highly reputed for its health-improving effects. Multiple pieces of evidence indicate that the consumption of berries is linked to enhancing human health and preventing or delaying the onset of chronic medical conditions. Compared with other fruit, elderberry is a very rich source of anthocyanins (approximately 80% of the polyphenol content). These polyphenols are the principals that essentially contribute to the high antioxidant and anti-inflammatory capacities and the health benefits of elderberry fruit extract. These health effects include attenuation of cardiovascular, neurodegenerative, and inflammatory disorders, as well as anti-diabetic, anticancer, antiviral, and immuno-stimulatory effects. Sales of elderberry supplements skyrocketed to $320 million over the year 2020, according to an American Botanical Council (ABC) report, which is attributable to the purported immune-enhancing effects of elderberry. In the current review, the chemical composition of the polyphenolic content of the European elderberry (Sambucus nigra) and the American elderberry (Sambucus canadensis), as well as the analytical techniques employed to analyze, characterize, and ascertain the chemical consistency will be addressed. Further, the factors that influence the consistency of the polyphenolic chemical composition, and hence, the consistency of the health benefits of elderberry extracts will be presented. Additionally, adulteration and safety as factors contributing to consistency will be covered. The role of elderberry in enhancing human health alone with the pharmacological basis, the cellular pathways, and the molecular mechanisms underlying the observed health benefits of elderberry fruit extracts will be also reviewed.

Effect-Directed Profiling of Akebia quinata and Clitoria ternatea via High-Performance Thin-Layer Chromatography, Planar Assays and High-Resolution Mass Spectrometry.

Two herbal plants, Akebia quinata D. leaf/fruit and Clitoria ternatea L. flower, well-known in traditional medicine systems, were investigated using a non-target effect-directed profiling. High-performance thin-layer chromatography (HPTLC) was combined with 11 different effect-directed assays, including two multiplex bioassays, for assessing their bioactivity. Individual active zones were heart-cut eluted for separation via an orthogonal high-performance liquid chromatography column to heated electrospray ionization high-resolution mass spectrometry (HPLC-HESI-HRMS) for tentative assignment of molecular formulas according to literature data. The obtained effect-directed profiles provided information on 2,2-diphenyl-1-picrylhydrazyl scavenging, antibacterial (against Bacillus subtilis and Aliivibrio fischeri), enzyme inhibition (tyrosinase, α-amylase, ß-glucuronidase, butyrylcholinesterase, and acetylcholinesterase), endocrine (agonists and antagonists), and genotoxic (SOS-Umu-C) activities. The main bioactive compound zones in A. quinata leaf were tentatively assigned to be syringin, vanilloloside, salidroside, α-hederin, cuneataside E, botulin, and oleanolic acid, while salidroside and quinatic acids were tentatively identified in the fruit. Taraxerol, kaempherol-3-rutinoside, kaempferol-3-glucoside, quercetin-3-rutinoside, and octadecenoic acid were tentatively found in the C. ternatea flower. This straightforward hyphenated technique made it possible to correlate the biological properties of the herbs with possible compounds. The meaningful bioactivity profiles contribute to a better understanding of the effects and to more efficient food control and food safety.

Modulation of in Vitro SARS-CoV-2 Infection by Stephania tetrandra and Its Alkaloid Constituents.

Botanical natural products have been widely consumed for their purported usefulness against COVID-19. Here, six botanical species from multiple sources and 173 isolated natural product compounds were screened for blockade of wild-type (WT) SARS-CoV-2 infection in human 293T epithelial cells overexpressing ACE-2 and TMPRSS2 protease (293TAT). Antiviral activity was demonstrated by an extract from Stephania tetrandra. Extract fractionation, liquid chromatography-mass spectrometry (LC-MS), antiviral assays, and computational analyses revealed that the alkaloid fraction and purified alkaloids tetrandrine, fangchinoline, and cepharanthine inhibited WT SARS-CoV-2 infection. The alkaloids and alkaloid fraction also inhibited the delta variant of concern but not WT SARS-CoV-2 in VeroAT cells. Membrane permeability assays demonstrate that the alkaloids are biologically available, although fangchinoline showed lower permeability than tetrandrine. At high concentrations, the extract, alkaloid fractions, and pure alkaloids induced phospholipidosis in 293TAT cells and less so in VeroAT cells. Gene expression profiling during virus infection suggested that alkaloid fraction and tetrandrine displayed similar effects on cellular gene expression and pathways, while fangchinoline showed distinct effects on cells. Our study demonstrates a multifaceted approach to systematically investigate the diverse activities conferred by complex botanical mixtures, their cell-context specificity, and their pleiotropic effects on biological systems.

Exploring the Multitarget Potential of Iridoids: Advances and Applications.

Iridoids are secondary plant metabolites that are multitarget compounds active against various diseases. Iridoids are structurally classified into iridoid glycosides and non-glycosidic iridoids according to the presence or absence of intramolecular glycosidic bonds; additionally, iridoid glycosides can be further subdivided into carbocyclic iridoids and secoiridoids. These monoterpenoids belong to the cyclopentan[c]-pyran system, which has a wide range of biological activities, including antiviral, anticancer, antiplasmodial, neuroprotective, anti-thrombolytic, antitrypanosomal, antidiabetic, hepatoprotective, anti-oxidant, antihyperlipidemic and anti-inflammatory properties. The basic chemical structure of iridoids in plants (the iridoid ring scaffold) is biosynthesized in plants by the enzyme iridoid synthase using 8-oxogeranial as a substrate. With advances in phytochemical research, many iridoid compounds with novel structure and outstanding activity have been identified in recent years. Biologically active iridoid derivatives have been found in a variety of plant families, including Plantaginaceae, Rubiaceae, Verbenaceae, and Scrophulariaceae. Iridoids have the potential of modulating many biological events in various diseases. This review highlights the multitarget potential of iridoids and includes a compilation of recent publications on the pharmacology of iridoids. Several in vitro and in vivo models used, along with the results, are also included in the paper. This paper's systematic summary was created by searching for relevant iridoid material on websites such as Google Scholar, PubMed, SciFinder Scholar, Science Direct, and others. The compilation will provide the researchers with a thorough understanding of iridoid and its congeners, which will further help in designing a large number of potential compounds with a strong impact on curing various diseases.

Bioactive Compositions of Cinnamon (Cinnamomum verum J. Presl) Extracts and Their Capacities in Suppressing SARS-CoV-2 Spike Protein Binding to ACE2, Inhibiting ACE2, and Scavenging Free Radicals.

Cinnamon (Cinnamomum verum J. Presl) bark and its extracts are popular ingredients added to food and supplement products. It has various health effects, including potentially reducing the risk of coronavirus disease-2019 (COVID-19). In our study, the bioactives in cinnamon water and ethanol extracts were chemically identified, and their potential in suppressing SARS-CoV-2 spike protein-angiotensin-converting enzyme 2 (ACE2) binding, reducing ACE2 availability, and scavenging free radicals was investigated. Twenty-seven and twenty-three compounds were tentatively identified in cinnamon water and ethanol extracts, respectively. Seven compounds, including saccharumoside C, two emodin-glucuronide isomers, two physcion-glucuronide isomers, and two type-A proanthocyanidin hexamers, were first reported in cinnamon. Cinnamon water and ethanol extracts suppressed the binding of SARS-CoV-2 spike protein to ACE2 and inhibited ACE2 activity in a dose-dependent manner. Cinnamon ethanol extract had total phenolic content of 36.67 mg gallic acid equivalents (GAE)/g and free radical scavenging activities against HO• and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS•+) of 1688.85 and 882.88 µmol Trolox equivalents (TE)/g, which were significantly higher than those of the water extract at 24.12 mg GAE/g and 583.12 and 210.36 µmol TE/g. The free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) of cinnamon ethanol extract was lower than that of the water extract. The present study provides new evidence that cinnamon reduces the risk of SARS-CoV-2 infection and COVID-19 development.

Maackia amurensis Rupr. et Maxim.: Supercritical CO2 Extraction and Mass Spectrometric Characterization of Chemical Constituents.

Three types of extraction were used to obtain biologically active substances from the heartwood of M. amurensis: supercritical CO2 extraction, maceration with EtOH, and maceration with MeOH. The supercritical extraction method proved to be the most effective type of extraction, giving the highest yield of biologically active substances. Several experimental conditions were investigated in the pressure range of 50-400 bar, with 2% of ethanol as co-solvent in the liquid phase at a temperature in the range of 31-70 °C. The most effective extraction conditions are: pressure of 100 bar and a temperature of 55 °C for M. amurensis heartwood. The heartwood of M. amurensis contains various polyphenolic compounds and compounds of other chemical groups with valuable biological activity. Tandem mass spectrometry (HPLC-ESI-ion trap) was applied to detect target analytes. High-accuracy mass spectrometric data were recorded on an ion trap equipped with an ESI source in the modes of negative and positive ions. The four-stage ion separation mode was implemented. Sixty-six different biologically active components have been identified in M. amurensis extracts. Twenty-two polyphenols were identified for the first time in the genus Maackia.

Extraction of Antioxidant Compounds from Brazilian Green Propolis Using Ultrasound-Assisted Associated with Low- and High-Pressure Extraction Methods.

The demand for bee products has been growing, especially regarding their application in complementary medicine. Apis mellifera bees using Baccharis dracunculifolia D.C. (Asteraceae) as substrate produce green propolis. Among the examples of bioactivity of this matrix are antioxidant, antimicrobial, and antiviral actions. This work aimed to verify the impact of the experimental conditions applied in low- and high-pressure extractions of green propolis, using sonication (60 kHz) as pretreatment to determine the antioxidant profile in the extracts. Total flavonoid content (18.82 ± 1.15-50.47 ± 0.77 mgQE·g-1), total phenolic compounds (194.12 ± 3.40-439.05 ± 0.90 mgGAE·g-1) and antioxidant capacity by DPPH (33.86 ± 1.99-201.29 ± 0.31 µg·mL-1) of the twelve green propolis extracts were determined. By means of HPLC-DAD, it was possible to quantify nine of the fifteen compounds analyzed. The results highlighted formononetin (4.76 ± 0.16-14.80 ± 0.02 mg·g-1) and p-coumaric acid (

The Effect of the Plant Stabilisation Method on the Composition and Antioxidant Properties of Elderflower (Sambucus nigra L.) Extract.

Elderflower extracts are known to be a source of valuable substances that show a wide spectrum of biological activity, including antibacterial and antiviral properties, which demonstrate a degree of effectiveness against SARS CoV-2. In this work, the influence of fresh inflorescence stabilisation methods (freezing, air drying, and lyophilisation) and extraction parameters on the composition and antioxidant properties of the extracts were studied. Wild elderflower plants growing in the Malopolska Region of Poland were studied. Antioxidant activities were evaluated by 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging ability and ferric-reducing antioxidant power assays. The total phenolic content was determined using the Folin-Ciocalteu method and the phytochemical profile of the extracts was analysed using HPLC. The obtained results showed that the best method for the stabilisation of elderflower was lyophilisation, and the determined optimal maceration parameters were 60% methanol as a solvent and a process time of 1-2 days.

Essential Oil of Cestrum diurnum L.: GC/MS Analysis, in Vitro and in Silico Anti-HCoV-229E Effects and Inhibitory Activity against LPS-Induced Inflammation.

Cestrum diurnum L. (Solanaceae) is a fragrant ornamental tree cultivated in different parts around the world. In this study, the essential oil (EO) of the aerial parts was extracted by hydrodistillation (HD), steam distillation (SD) and microwave-assisted hydro-distillation (MAHD). GC/MS analysis of the three EOs revealed that phytol represents the major component in SD-EO and MAHD-EO (40.84 and 40.04 %, respectively); while in HD-EO it only represented 15.36 %. The SD-EO showed a strong antiviral activity against HCoV-229E with IC50 of 10.93 µg/mL, whereas, MAHD-EO and HD-EO showed a moderate activity with IC50 values of 119.9 and 148.2 µg/mL, respectively. The molecular docking of EO major components: phytol, octadecyl acetate and tricosane showed a strong binding to coronavirus 3-CL (pro). Moreover, the three EOs (50 µg/mL) decreased the levels of NO, IL-6 and TNF-α and suppressed IL-6 and TNF-α gene expression in LPS-induced inflammation model in RAW264.7 macrophage cell lines.

Multifaceted antiviral therapeutic potential of dietary flavonoids: Emerging trends and future perspectives.

Phytochemicals are the natural biomolecules produced by plants via primary or secondary metabolism, which have been known to have many potential health benefits to human beings. Flavonoids or phytoestrogens constitute a major group of such phytochemicals widely available in variety of vegetables, fruits, herbs, tea, and so forth, implicated in a variety of bio-pharmacological and biochemical activities against diseases including bacterial, viral, cancer, inflammatory, and autoimmune disorders. More recently, these natural biomolecules have been shown to have effective antiviral properties via therapeutically active ingredients within them, acting at different stages of infection. Current review emphasizes upon the role of these flavonoids in physiological functions, prevention and treatment of viral diseases. More so the review focuses specifically upon the antiviral effects exhibited by these natural biomolecules against RNA viruses including coronaviruses. Furthermore, the article would certainly provide a lead to the scientific community for the effective therapeutic antiviral use of flavonoids using potential cost-effective tools for improvement of the pharmacokinetics, bioavailability, and biodistribution of such compounds for the concrete action along with the promotion of human health.

Barbaloin: an amazing chemical from the 'wonder plant' with multidimensional pharmacological attributes.

Aloe vera (L.) Burm.f. is nicknamed the 'Miracle plant' or sometimes as the 'Wonder plant'. It is a plant that has been used since ancient times for the innumerable health benefits associated with it. It is one of the important plants that has its use in conventional medicinal treatments. It is a perennial succulent, drought-tolerant member of the family Asphodelaceae. There are scores of properties associated with the plant that help in curing various forms of human ailments. Extracts and gels obtained from plants have been shown to be wonderful healers of different conditions, mainly various skin problems. Also, this plant is popular in the cosmetics industry. The underlying properties of the plant are now mainly associated with the natural phytochemicals present in the plant. Diverse groups of phytoingredients are found in the plant, including various phenolics, amino acids, sugars, vitamins, and different other organic compounds, too. One of the primary ingredients found in the plant is the aloin molecule. It is an anthraquinone derivative and exists as an isomer of Aloin A and Aloin B. Barbaloin belonging to the first group is a glucoside of the aloe-emodin anthrone molecule. Various types of pharmacological properties exhibited by the plant can be attributed to this chemical. Few significant ones are antioxidant, anti-inflammatory, anti-diabetic, anti-cancer, anti-microbial, and anti-viral, along with their different immunity-boosting actions. Recently, molecular coupling studies have also found the role of these molecules as a potential cure against the ongoing COVID-19 disease. This study comprehensively focuses on the numerous pharmacological actions of the primary compound barbaloin obtained from the Aloe vera plant along with the mechanism of action and the potent application of these natural molecules under various conditions.

Therapeutic Application, Phytoactives and Pharmacology of Tinospora cordifolia: An Evocative Review.

Tinospora cordifolia (Guduchi or Gurjo), a herbaceous vine or climbing deciduous shrub, is consider as an important medicine in the Ayurvedic system of medication, which is available in India, China, Myanmar, Bangladesh and Srilanka. Menispermaceae is the family of this compound. T. cordifolia have a variety of properties to treat various ailments such as fevers, jaundice, diabetes, dysentery, urinary infections, and skin diseases. This compound has been subjected to many chemicals, pharmacological, pre-clinical, or clinical investigations and some new therapeutic potential effects have been indicated. This review aims to summarize the critical information concerning in areas of chemical constituents, chemical structure, and pharmacokinetic activities such as anti-diabetic, anticancer, immune-modulatory, antivirus (especially in silico study about COVID-19), antioxidant, antimicrobial, hepatoprotective and its effect on cardiovascular and neurological disorders as well as rheumatoid arthritis. This traditional herb needs more experimental study on the clinical, pre-clinical study, and clinical efficacy of these compounds for the prevention and treatment of COVID-19 and needs large-scale clinical studies to prove the clinical efficacy of this compound, especially in stress-related diseases and other neuronal disorders.

Green Synthesized Zinc Oxide Nanoparticles Based on Cestrum diurnum L. of Potential Antiviral Activity against Human Corona 229-E Virus.

SARS-CoV-2 has caused more than 596 million infections and 6 million fatalities globally. Looking for urgent medication for prevention, treatment, and rehabilitation is obligatory. Plant extracts and green synthesized nanoparticles have numerous biological activities, including antiviral activity. HPLC analysis of C. dirnum L. leaf extract showed that catechin, ferulic acid, chlorogenic acid, and syringic acid were the most major compounds, with concentrations of 1425.16, 1004.68, 207.46, and 158.95 µg/g, respectively. Zinc nanoparticles were biosynthesized using zinc acetate and C. dirnum extract. TEM analysis revealed that the particle size of ZnO-NPs varied between 3.406 and 4.857 nm. An XRD study showed the existence of hexagonal crystals of ZnO-NPs with an average size of 12.11 nm. Both ZnO-NPs (IC50 = 7.01 and CC50 = 145.77) and C. dirnum L. extract (IC50 = 61.15 and CC50 = 145.87 µg/mL) showed antiviral activity against HCOV-229E, but their combination (IC50 = 2.41 and CC50 = 179.23) showed higher activity than both. Molecular docking was used to investigate the affinity of some metabolites against the HCOV-229E main protease. Chlorogenic acid, solanidine, and catchin showed high affinity (-7.13, -6.95, and -6.52), compared to the ligand MDP (-5.66 Kcal/mol). Cestrum dinurum extract and ZnO-NPs combination should be subjected to further studies to be used as an antiviral drug.

Antiviral activity of berberine.

Plants are a rich source of new antiviral, pharmacologically active agents. The naturally occurring plant alkaloid berberine (BBR) is one of the phytochemicals with a broad range of biological activity, including anticancer, anti-inflammatory and antiviral activity. BBR targets different steps in the viral life cycle and is thus a good candidate for use in novel antiviral drugs and therapies. It has been shown that BBR reduces virus replication and targets specific interactions between the virus and its host. BBR intercalates into DNA and inhibits DNA synthesis and reverse transcriptase activity. It inhibits replication of herpes simplex virus (HSV), human cytomegalovirus (HCMV), human papillomavirus (HPV), and human immunodeficiency virus (HIV). This isoquinoline alkaloid has the ability to regulate the MEK-ERK, AMPK/mTOR, and NF-κB signaling pathways, which are necessary for viral replication. Furthermore, it has been reported that BBR supports the host immune response, thus leading to viral clearance. In this short review, we focus on the most recent studies on the antiviral properties of berberine and its derivatives, which might be promising agents to be considered in future studies in the fight against the current pandemic SARS-CoV-2, the virus that causes COVID-19.

An efficient method for qualitation and quantitation of multi-components of the herbal medicine Qingjin Yiqi Granules.

Qingjin Yiqi Granules (QJYQ) is a Traditional Chinese Medicines (TCMs) prescription for the patients with post-COVID-19 condition. It is essential to carry out the quality evaluation of QJYQ. A comprehensive investigation was conducted by establishing deep-learning assisted mass defect filter (deep-learning MDF) mode for qualitative analysis, ultra-high performance liquid chromatography and scheduled multiple reaction monitoring method (UHPLC-sMRM) for precise quantitation to evaluate the quality of QJYQ. Firstly, a deep-learning MDF was used to classify and characterize the whole phytochemical components of QJYQ based on the mass spectrum (MS) data of ultra-high performance liquid chromatography quadrupole time of flight tandem mass spectrometry (UHPLC-Q-TOF/MS). Secondly, the highly sensitive UHPLC-sMRM data-acquisition method was established to quantify the multi-ingredients of QJYQ. Totally, nine major types of phytochemical compounds in QJYQ were intelligently classified and 163 phytochemicals were initially identified. Furthermore, fifty components were rapidly quantified. The comprehensive evaluation strategy established in this study would provide an effective tool for accurately evaluating the quality of QJYQ as a whole.

Biological activities of endophytic fungi isolated from Annona muricata Linnaeus: a systematic review.

This systematic review integrates the data available in the literature regarding the biological activities of the extracts of endophytic fungi isolated from Annona muricata and their secondary metabolites. The search was performed using four electronic databases, and studies' quality was evaluated using an adapted assessment tool. The initial database search yielded 436 results; ten studies were selected for inclusion. The leaf was the most studied part of the plant (in nine studies); Periconia sp. was the most tested fungus (n = 4); the most evaluated biological activity was anticancer (n = 6), followed by antiviral (n = 3). Antibacterial, antifungal, and antioxidant activities were also tested. Terpenoids or terpenoid hybrid compounds were the most abundant chemical metabolites. Phenolic compounds, esters, alkaloids, saturated and unsaturated fatty acids, aromatic compounds, and peptides were also reported. The selected studies highlighted the biotechnological potentiality of the endophytic fungi extracts from A. muricata. Consequently, it can be considered a promising source of biological compounds with antioxidant effects and active against different microorganisms and cancer cells. Further research is needed involving different plant tissues, other microorganisms, such as SARS-CoV-2, and different cancer cells.

Identifying the Anti-MERS-CoV and Anti-HcoV-229E Potential Drugs from the Ginkgo biloba Leaves Extract and Its Eco-Friendly Synthesis of Silver Nanoparticles.

The present study aimed to estimate the antiviral activities of Ginkgo biloba (GB) leaves extract and eco-friendly free silver nanoparticles (Ag NPs) against the MERS-CoV (Middle East respiratory syndrome-coronavirus) and HCoV-229E (human coronavirus 229E), as well as isolation and identification of phytochemicals from GB. Different solvents and high-performance liquid chromatography (HPLC) were used to extract and identify flavonoids and phenolic compounds from GB leaves. The green, silver nanoparticle synthesis was synthesized from GB leaves aqueous extract and investigated for their possible effects as anti-coronaviruses MERS-CoV and HCoV-229E using MTT assay protocol. To verify the synthesis of Ag NPs, several techniques were employed, including X-ray diffraction (XRD), scan, transmission electron microscopy, FT-IR, and UV-visible spectroscopy. The highest contents of flavonoids and phenolic compounds were recorded for acetone, methanol, and ethanol as mixtures with water, in addition to pure water. HPLC flavonoids were detected as apegenin, luteolin, myricetin, and catechin, while HPLC phenolic compounds were pyrogallol, caffeic acid, gallic acid, and ellagic acid. In addition, our results revealed that Ag NPs were produced through the shift from yellow to dark brown. TEM examination of Ag NPs revealed spherical nanoparticles with mean sizes ranging from 5.46 to 19.40 nm and an average particle diameter of 11.81 nm. A UV-visible spectrophotometric investigation revealed an absorption peak at λ max of 441.56 nm. MTT protocol signified the use of GB leaves extract as an anti-coronavirus to be best from Ag NPs because GB extract had moderate anti-MERS-CoV with SI = 8.94, while had promising anti-HCov-229E, with an SI of 21.71. On the other hand, Ag NPs had a mild anti-MERS-CoV with SI = 4.23, and a moderate anti-HCoV-229E, with an SI of 7.51.