Genus Pterocarpus: A review of ethnopharmacology, phytochemistry, biological activities, and clinical evidence

Antibacterial and anti-coronavirus investigation of selected Senegalese plant species according to an ethnobotanical survey

ETHNOPHARMACOLOGICAL RELEVANCE

In Senegal, upper and lower respiratory tract infections constitute a real health problem. To manage these disorders, most people rely on the use of local medicinal plants. This is particularly the case for species belonging to the botanical families, Combretaceae, Fabaceae, Myrtaceae and Rubiaceae, which are widely used to treat various respiratory problems such as colds, flu, rhinitis, sinusitis, otitis, angina, bronchitis, bronchiolitis and also pneumonia.

AIM OF THE STUDY

The aim of this study was to identify medicinal plants traditionally used for the management of infectious diseases, in particular those of the respiratory tract. On the basis of these ethnopharmacological uses, this study made it possible to highlight the antibacterial, antiviral and cytotoxic activities of selected plant species.

MATERIALS AND METHODS

An ethnobotanical survey was conducted in Senegal among informants, including herbalists, traditional healers, and households, using medicinal plants in the management of infectious diseases, with a focus on respiratory tract infections. The most cited plant species were evaluated in vitro on a panel of 18 human pathogenic bacteria may be involved in respiratory infections and against the human coronavirus HCoV-229E in Huh-7 cells. The antiviral activity of the most active extracts against HCoV-229E was also evaluated on COVID-19 causing agent, SARS-CoV-2 in Vero-81 cells. In parallel, cytotoxic activities were evaluated on Huh-7 cells.

RESULTS

A total of 127 informants, including 100 men (78.74%) and 27 women (21.26%) participated in this study. The ethnobotanical survey led to the inventory of 41 plant species belonging to 19 botanical families used by herbalists and/or traditional healers and some households to treat infectious diseases, with a specific focus on upper respiratory tract disorders. Among the 41 plant species, the most frequently mentioned in the survey were Guiera senegalensis J.F. Gmel. (95.2%), Combretum glutinosum Perr. Ex DC. (93.9%) and Eucalyptus spp. (82.8%). Combretaceae (30.2%) represented the most cited botanical family with six species, followed by Fabaceae (29.3%, 12 species). A total of 33 crude methanolic extracts of the 24 plant species selected for their number of citations were evaluated in vitro for their antimicrobial and cytotoxic activities. Guiera senegalensis, Combretum glutinosum, Vachellia nilotica subsp. tomentosa (Benth.) Kyal. & Boatwr, Eucalyptus camaldulensis Dehnh., and Terminalia avicennioides Guill. & Perr., showed antibacterial activities. The most active plants against HCoV-229E were: Ficus sycomorus L., Mitragyna inermis (Willd.) Kuntze, Pterocarpus erinaceus Poir., and Spermacoce verticillata L. One of these plants, Mitragyna inermis, was also active against SARS-CoV-2.

CONCLUSION

This work confirmed the anti-infective properties of plant species traditionally used in Senegal. Overall, the most frequently cited plant species showed the best antibacterial activities. Moreover, some of the selected plant species could be considered as a potential source for the management of coronavirus infections. This new scientific data justified the use of these plants in the management of some infectious pathologies, especially those of the respiratory tract.

Anti-Aging Potential of Plants of the Anak Dalam Tribe, Jambi, Indonesia

The process of skin aging is a physiological phenomenon that can not be avoided. According to global population data, the rate of aging increases by approximately 13% every year. The impact of skin aging has become a significant concern and challenge for developed countries. Consequently, there has been a search for potential new anti-aging agents. This review aims to provide an overview of the current research status of plants of the Anak Dalam Tribe (Indonesian: Suku Anak Dalam [SAD]; referred to as SAD henceforth) in Jambi Province, Indonesia, for the development of potential new anti-aging agents. One such discovery is a product derived from natural ingredients with the ability to prevent premature aging. These new anti-aging plants have been used for centuries by the Anak Dalam tribe, for treating skin diseases and maintaining skin health through traditional remedies. Recent research on herbal formulations used by the SAD community in Indonesia for skin beauty treatments, reported by Research on Medicinal Plants and Herbs or RISTOJA, indicates that 64 plant species are used for skin care. Among these plants, Toona sinensis, Curcuma heyneana, Curcuma zedoaria, Curcuma longa, and Kaempferia rotunda are the most commonly used medicinal plants with anti-aging properties. T. sinensis is a tree, while the others are herbs. T. sinensis shows the highest potential for development as an anti-aging agent, with its extracts, active fractions, and bioactive quercetin isolates known to possess strong anti-aging activities both in vitro and in vivo. Furthermore, C. heyneana, C. longa, C. zedoaria, and K. rotunda also show potential for further research, and three of them have demonstrated good potential for in vivo anti-aging activities. Only K. rotunda demonstrates relatively weaker antioxidant activity compared to T. sinensis, C. heyneana, C. longa, and C. zedoaria. Nevertheless, K. rotunda can still be developed to search for potential opportunities as agents with other activities, while T. sinensis, C. heyneana, C. longa, and C. zedoaria in the findings could be an opportunity to explore the potential of new anti-aging agents. In conclusion, of the five medicinal plants traditionally used by the SAD in Jambi, Indonesia, C. longa has received the most extensive research and shows potential for the development of anti-aging solutions. C. zedoaria, C. heyneana and K. rotunda show good potential for in vivo anti-aging activity. T. sinensis is the least-studied medicinal plant. Nevertheless, it has potential for development, as it is widely used by the SAD community for both traditional medicine and skin care.

Integrating Chemical Profiling, In Vivo Study, and Network Pharmacology to Explore the Anti-inflammatory Effect of Pterocarpus dalbergioides Fruits and Its Correlation with the Major Phytoconstituents

The purpose of this study is to explore the anti-inflammatory activity of Pterocarpus dalbergioides fruit extract (PFE) and the underlying mechanism. Chemical profiling using ultraperformance liquid chromatography/mass spectrometry identified 28 compounds in PFE (12 flavonoids, 5 fatty acids, 4 phenolic compounds, 3 alkaloids, 2 sesquiterpenes, and 2 xanthophylls). PFE (2 g/kg) significantly inhibited carrageenan-induced rat paw edema after 4 h of administration (42% inhibition). A network-based strategy and molecular docking studies were utilized to uncover the anti-inflammatory mechanism. Out of the identified compounds, 16 compounds with DL ≥ 0.18 and F ≥ 30% were selected using bioavailability (F) and drug-likeness (DL) metrics. The network analysis revealed that 90 genes are considered key targets for the selected compounds and linked to the anti-inflammatory effect. Among all compounds, linoleic acid was found to be the top-most active constituent as it targets maximum genes. Four targets (TNF, IL6, AKT1, and CCL2) among the top 10 genes were found to be the main target genes that may contribute to the anti-inflammatory potential of PFE. Furthermore, KEGG (Kyoto encyclopedia of genes and genomes) pathway analysis revealed that PFE might regulate inflammation through five pathways: neuroactive ligand-receptor interaction, lipid and atherosclerosis, fluid shear stress and atherosclerosis, TNF signaling pathway, and rheumatoid arthritis. The docking study predicted the significant binding affinity between the top four active constituents (linoleic acid, 9-octadecenoic acid, 11,12,13-trihydroxy-9-octadecenoic acid, and rhamnetin-3-O-rhamnoside) and the selected target proteins (TNF and AKT1). The findings highlight PFE as a promising drug lead for controlling inflammation.

Bioactivity of Wild and Cultivated Legumes: Phytochemical Content and Antioxidant Properties

The global demand for increased meat production has brought to the surface several obstacles concerning environmental impacts, animals’ welfare, and quality features, revealing the need to produce safe foodstuffs with an environmentally acceptable procedure. In this regard, the incorporation of legumes into animal diets constitutes a sustainable way out that prevents these apprehensions. Legumes are plant crops belonging to the Fabaceae family and are known for their rich content of secondary metabolites., displaying significant antioxidant properties and a series of health and environmental benefits. The study herein aims to investigate the chemical composition and antioxidant activities of indigenous and cultivated legume plants used for food and feed. The respective results indicate that the methanolic extract of Lathyrus laxiflorus (Desf.) Kuntze displayed the highest phenolic (64.8 mg gallic acid equivalents/g extract) and tannin (419.6 mg catechin equivalents/g extract) content, while the dichloromethane extract of Astragalus glycyphyllos L., Trifolium physodes Steven ex M.Bieb. and Bituminaria bituminosa (L.) C.H.Stirt. plant samples exhibited the richest content in carotenoids lutein (0.0431 mg/g A. glycyphyllos extract and 0.0546 mg/g B. bituminosa extract), α-carotene (0.0431 mg/g T. physodes extract) and β-carotene (0.090 mg/g T. physodes extract and 0.3705 mg/g B. bituminosa extract) establishing their potential role as vitamin A precursor sources. Results presented herein verify the great potential of Fabaceae family plants for utilization as pasture plants and/or dietary ingredients, since their cultivation has a positive impact on the environment, and they were found to contain essential nutrients capable to improve health, welfare, and safety.

Medicinal Uses of the Fabaceae Family in Zimbabwe: A Review

The current study is aimed at providing a systematic review of the ethnomedicinal, phytochemical and pharmacological properties of Fabaceae species used as sources of traditional medicinies in Zimbabwe. Fabaceae is one of the well-known plant families of ethnopharmacological importance. Of the approximately 665 species of the Fabaceae family occurring in Zimbabwe, about 101 are used for medicinal purposes. Many communities in the country, mainly in peri-urban, rural and marginalized areas with limited access to healthcare facilities, rely on traditional medicines as their primary healthcare. The study reviewed research studies undertaken on Zimbabwe's Fabaceae species during 1959 to 2022. Information was gathered from literature sourced from Google Scholar, Science Direct, Scopus, PubMed, books, dissertations, theses and scientific reports. This study showed that 101 species are traditionally used to manage human and animal diseases in Zimbabwe. The genera with the highest number of medicinal uses are Indigofera, Senna, Albizia, Rhynchosia and Vachellia. Species of these genera are used as traditional medicines against 134 medical conditions, mainly gastrointestinal conditions, female reproductive conditions, respiratory conditions and sexually transmitted infections. Shrubs (39.0%), trees (37.0%) and herbs (18.0%) are the primary sources of traditional medicines, while roots (80.2%), leaves (36.6%), bark (27.7%) and fruits (8.9%) are the most widely used plant parts. Many of Zimbabwe's Fabaceae species used as sources of traditional medicines have been assessed for their phytochemical and pharmacological properties, corroborating their medicinal uses. However, there is a need to unravel the therapeutic potential of the family through further ethnopharmacological research focusing on toxicological studies, in vitro and in vivo models, biochemical assays and pharmacokinetic studies.

In silico anti-SARS-CoV-2, antiplasmodial, antioxidant, and antimicrobial activities of crude extracts and homopterocarpin from heartwood of Pterocarpus macrocarpus Kurz

Natural products play an essential role in new drug discovery. In the present study, we determined the anti-SARS-CoV-2 (severe acute respiratory syndrome-related coronavirus-2), antioxidant, antiplasmodial, and antimicrobial activities of Pterocarpus macrocarpus Kurz. heartwood and structurally characterized the bioactive compounds. P. macrocarpus Kurz. heartwood was macerated with n-hexane, ethyl acetate, and ethanol, respectively, for 7 days, three times. The compounds were isolated by recrystallization with n-hexane and evaluated by thin-layer chromatography (TLC), gas chromatography-mass spectrophotometry (GC-MS), Fourier transform infrared spectroscopy (FITR), and nuclear magnetic resonance (NMR) spectroscopy. Ethyl acetate, ethanol, n-hexane extracts, and homopterocarpin exhibited antiplasmodial activity at 1.78, 2.21, 7.11, and 0.52 μg/ml, respectively, against P. falciparum 3D7 with low toxicity (selectivity index/SI ≥ 28.46). GC-MS identified compound showed in silico anti-SARS-CoV-2 binding affinity with stigmasterol and SARS-CoV-2 helicase of -8.2 kcal/mol. Ethyl acetate extract exhibited the best antioxidant activity against DPPH (0.76 ± 0.92 μg/ml) and ABTS (0.61 ± 0.46 μg/ml). They also demonstrated antimicrobial activity against B. subtilis, ethanol and ethyl acetate extracts against E. coli and C. albicans, and ethanol extract against S. aureus with diameter zone of inhibition of more than 1 cm. The results highlighted antiplasmodial activity of extracts and homopterocarpin from P. macrocarpus Kurz. heartwood and its potent binding in silico to anti-SARS-CoV-2 proteins with low toxicity. This study also confirmed that extracts exhibited antioxidant and antimicrobial activities. Further studies are needed to assess the safety and clinical trial of P. macrocarpus Kurz. for development as new drug candidate.

In Silico Analysis of PTP1B Inhibitors and TLC-MS Bioautography-Based Identification of Free Radical Scavenging and α-Amylase Inhibitory Compounds from Heartwood Extract of Pterocarpus marsupium

Type 2 diabetes mellitus leads to metabolic impairment caused by insulin resistance and hyperglycemia, giving rise to chronic diabetic complications and poor disease prognosis. The heartwood of Pterocarpus marsupium has been used in Ayurveda for a long time, and we sought to find the actual mechanism(s) driving its antidiabetic potential. Methanol was used to prepare the extract using a Soxhlet extraction, and the identification of metabolites was performed by thin-layer chromatography (TLC) and ultraperformance-liquid chromatography and mass spectroscopy (UP-LCMS). The antioxidant potential of methanolic heartwood extract of Pterocarpus marsupium MHPM was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and a reducing power assay. The α-amylase and α-glucosidase enzyme inhibitory potential of MHPM were investigated for their antidiabetic activity against acarbose. TLC-MS-bioautography was performed to identify the compounds responsible for possible antioxidant and antidiabetic activities. Moreover, targeting protein tyrosine phosphatase 1B (PTP1B), a key regulator of insulin resistance, by identified metabolites from MHPM through molecular docking and all-atom molecular dynamics (MD) simulations was also undertaken, suggesting its potential as an antidiabetic herb. The IC₅₀ of free-radical scavenging activity of MHPM against DPPH was 156.342 ± 10.70 μg/mL. Further, the IC₅₀ values of MHPM in α-amylase and α-glucosidase enzymatic inhibitions were 158.663 ± 10.986 μg/mL and 180.21 ± 11.35 μg/mL, respectively. TLC-MS-bioautography identified four free radical scavenging metabolites, and vanillic acid identified by MS analysis showed both free radical scavenging activity and α-amylase inhibitory activity. Among the identified metabolites from MHPM, epicatechin showed significant PTP1B docking interactions, and its MD simulations revealed that PTP1B forms a stable protein-ligand complex with epicatechin throughout the progression, which indicates that epicatechin may be used as a promising scaffold in the development of the antidiabetic drug after isolation from Pterocarpus marsupium. Overall, these findings imply that Pterocarpus marsupium is a source of valuable metabolites that are accountable for its antioxidant and antidiabetic properties.

Heartwood Extract of Pterocarpus marsupium Roxb. Offers Defense against Oxyradicals and Improves Glucose Uptake in HepG2 Cells

Diabetes mellitus leads to cellular damage and causes apoptosis by oxidative stress. Heartwood extract of Pterocarpus marsupium has been used in Ayurveda to treat various diseases such as leprosy, diabetes, asthma, and bronchitis. In this study, we worked out the mechanism of the antidiabetic potential of methanolic heartwood extract of Pterocarpus marsupium (MPME). First, metabolic profiling of MPME was done using gas chromatography-mass spectrometry (GCMS), ultra-performance liquid chromatography-mass spectroscopy (UPLC-MS), and high-performance thin-layer chromatography (HPTLC) to identify phenols, flavonoids, and terpenoids in MPME. Biological studies were carried out in vitro using the HepG2 cell line. Many antidiabetic compounds were identified including Quercetin. Methanolic extract of MPME (23.43 µg/mL-93.75 µg/mL) was found to be safe and effective in reducing oxyradicals in HepG2 cells. A concentration of 93.75 µg/mL improved glucose uptake efficiently. A significant decrease in oxidative stress, cell damage, and apoptosis was found in MPME-treated HepG2 cells. The study suggests that the heartwood of Pterocarpus marsupium offers good defense in HepG2 cells against oxidative stress and improves glucose uptake. The results show the significant antidiabetic potential of MPME using a HepG2 cell model. The effect seems to occur by reducing oxidative stress and sensitizing the cells towards glucose uptake, hence lowering systemic glucose levels, as well as rescuing ROS generation.

Chemical constituents from Pterocarpus santalinus and their inhibitory effects on nitric oxide production

A tropolone (2) and an acorane sesquiterpene (3), along with twenty previously known compounds were isolated from the heartwood of Pterocarpus santalinus. The structure of the isolated compounds was elucidated via 1D and 2D NMR spectroscopy and HRESIMS analysis. The absolute configuration of 3 was determined by comparison of the experimental and calculated ECD data. All compounds were evaluated for their inhibitory effects against nitric oxide production in LPS-stimulated RAW 264.7 macrophages.