Antimicrobial, Anthelmintic, and Antiviral Activity of Plants Traditionally Used for Treating Infectious Disease in the Similipal Biosphere Reserve, Odisha, India

Antibacterial, antidiabetic, acute toxicity, antioxidant, and nephroproductive competence of extracts of Lannea coromandelica fruit through in-vitro and in-vivo animal model investigation

The anti-dermatophytic (Proteus vulgaris, Klebsiella pneumoniae, Enterobacter aerogenes, Propionibacterium acnes, Staphylococcus aureus, and Streptococcus pyogenes) and nephroprotective activities of methanol and aqueous extracts obtained from Lannea coromandelica fruit were investigated through in-vitro (agar well diffusion method) and in-vivo (animal model) study. The methanol extract showed considerable antibacterial activity against selective bacterial pathogens at increased concentration (15.0 mg mL-1) in the following order P. vulgaris (35.2 ± 1.6 mm) > E. aerogenes (32.1 ± 2.1 mm) > K. pneumoniae (29.3±2 mm) > P. acnes (28.2 ± 2.4 mm) > S. aureus (25.5 ± 2.4 mm) > S. pyogenes (24.3 ± 2.1 mm) than aqueous extract. The MIC values of this methanol and aqueous extract was found as 2.5-7.5 mg mL-1 and 5.0 to 1.0 mg mL-1 respectively. Different treatment sets (A-E) on a rat-based animal model study revealed that the methanol extract has excellent antioxidant and nephroprotective activity, as well as favorable effects on essential biochemical substances involved in active metabolic activities. As demonstrated by histopathological and microscopic examination, the biologically active chemical present in methanol extract had a positive effect on serum markers, enzyme, and non-enzyme-based antioxidant activities, as well as lowering the toxicity caused by EG in the rat (as nephroprotective activity) renal cells.

Compound isolation through bioassay-guided fractionation of Tectona grandis leaf extract against Vibrio pathogens in shrimp

Tectona grandis Linn, commonly known as teak, is traditionally used to treat a range of diseases, including the common cold, headaches, bronchitis, scabies, diabetes, inflammation, and others. The present study was conducted with the purpose of isolating and identifying the active compounds in T. grandis leaf against a panel of Vibrio spp., which may induce vibriosis in shrimp, using bioassay-guided purification. The antimicrobial activity was assessed using the microdilution method, followed by the brine shrimp lethality assay to determine toxicity. Following an initial screening with a number of different solvents, it was established that the acetone extract was the most effective. The acetone extract was then exposed to silica gel chromatography followed by reversed-phase HPLC and further UHPLC-orbitrap-ion trap mass spectrometry to identify the active compounds. Three compounds called 1-hydroxy-2,6,8-trimethoxy-9,10-anthraquinone, deoxyanserinone B, and khatmiamycin were identified with substantial anti-microbial action against V. parahaemolyticus, V. alginolyticus, V. harveyi, V. anguillarum, and V. vulnificus. The IC50 values of the three compounds viz. 1-hydroxy-2,6,8-trimethoxy-9,10-anthraquinone, deoxyanserinone B, and khatmiamycin varied between 2 and 28, 7 and 38, and 7 and 56 μg/mL, respectively, which are as good as the standard antibiotics such as amoxicillin and others. The in vivo toxicity test revealed that the compounds were non-toxic to shrimp. The results of the study suggest that T. grandis leaf can be used as a source of bioactive compounds to treat Vibrio species in shrimp farming.

Model nematodes as a practical innovation to promote high throughput screening of natural products for anthelmintics discovery in South Asia: Current challenges, proposed practical and conceptual solutions

With the increasing prevalence of anthelmintic resistance in animals recorded globally, and the threat of resistance in human helminths, the need for novel anthelmintic drugs is greater than ever. Most research aimed at discovering novel anthelmintic leads relies on high throughput screening (HTS) of large libraries of synthetic small molecules in industrial and academic settings in developed countries, even though it is the tropical countries that are most plagued by helminth infections. Tropical countries, however, have the advantage of possessing a rich flora that may yield natural products (NP) with promising anthelmintic activity. Focusing on South Asia, which produces one of the world's highest research outputs in NP and NP-based anthelmintic discovery, we find that limited basic research and funding, a lack of awareness of the utility of model organisms, poor industry-academia partnerships and lack of technological innovations greatly limit anthelmintics research in the region. Here we propose that utilizing model organisms including the free-living nematode Caenorhabditis elegans, that can potentially allow rapid target identification of novel anthelmintics, and Oscheius tipulae, a closely related, free-living nematode which is found abundantly in soil in hotter temperatures, could be a much-needed innovation that can enable cost-effective and efficient HTS of NPs for discovering compounds with anthelmintic/antiparasitic potential in South Asia and other tropical regions that historically have devoted limited funding for such research. Additionally, increased collaborations at the national, regional and international level between parasitologists and pharmacologists/ethnobotanists, setting up government-industry-academia partnerships to fund academic research, creating a centralized, regional collection of plant extracts or purified NPs as a dereplication strategy and HTS library, and holding regional C. elegans/O. tipulae-based anthelmintics workshops and conferences to share knowledge and resources regarding model organisms may collectively promote and foster a NP-based anthelmintics landscape in South Asia and beyond.

Traditional medicinal plants in the treatment of gastrointestinal parasites in humans: A systematic review and meta-analysis of clinical and experimental evidence

Gastrointestinal (GI) parasites cause significant morbidity and mortality worldwide. The use of conventional antiparasitic drugs is often inhibited due to limited availability, side effects or parasite resistance. Medicinal plants can be used as alternatives or adjuncts to current antiparasitic therapies. This systematic review and meta-analysis aimed to critically synthesise the literature on the efficacy of different plants and plant compounds against common human GI parasites and their toxicity profiles. Searches were conducted from inception to September 2021. Of 5393 screened articles, 162 were included in the qualitative synthesis (159 experimental studies and three randomised control trials [RCTs]), and three articles were included in meta-analyses. A total of 507 plant species belonging to 126 families were tested against different parasites, and most of these (78.4%) evaluated antiparasitic efficacy in vitro. A total of 91 plant species and 34 compounds were reported as having significant in vitro efficacy against parasites. Only a few plants (n = 57) were evaluated for their toxicity before testing their antiparasitic effects. The meta-analyses revealed strong evidence of the effectiveness of Lepidium virginicum L. against Entamoeba histolytica with a pooled mean IC50 of 198.63 μg/mL (95% CI 155.54-241.72). We present summary tables and various recommendations to direct future research.

Yellow Himalayan Raspberry (Rubus ellipticus Sm.): Ethnomedicinal, Nutraceutical, and Pharmacological Aspects

Yellow Himalayan raspberry (Rubus ellipticus Sm., Rosaceae) is a native species of the Indian subcontinent, Southern China, and the Philippines, which has been historically used as a traditional medicine and food. All of the parts of this plant have been used in traditional medicine to treat respiratory ailments, diabetes, and gastrointestinal disorder, and as an anti-infective agent. The scientific evaluation revealed a richness of macronutrients, micronutrients, and minerals in the fruits, indicating its potential use as a nutraceutical. Furthermore, this plant has been found to be rich in various secondary metabolites, including polyphenols, flavonoids, anthocyanins, tannins, and terpenoids. Ascorbic acid, kaempferol, gallic acid, and catechin are some of the compounds found in this plant, which have been widely discussed for their health benefits. Furthermore, various extracts and compounds obtained from R. ellipticus have shown antioxidant, antidiabetic, anticancer, anti-inflammatory, nephroprotective, antipyretic, anticonvulsant, and anti-infective activities investigated through different study models. These findings in the literature have validated some of the widespread uses of the fruits in folk medicinal systems and the consumption of this nutritious wild fruit by local communities. In conclusion, R. ellipticus holds strong potential for its development as a nutraceutical. It can also improve the nutritional status of villagers and uplift the economy if properly utilized and marketed.

Study on the absolute configuration and biological activity of rotenoids from the leaves and twigs of Millettia pyrrhocarpa Mattapha, Forest & Hawkins, sp. Nov

BACKGROUND

M. pyrrhocarpa is a new plant in the Fabaceae: Faboideae family that is found in Thailand. A literature search revealed that the Milletia genus is rich in bioactive compounds possessing a wide range of biological activities. In this study, we aimed to isolate novel bioactive compounds and to study their bioactivities.

METHODS

The hexane, ethyl acetate, and methanol extracts from the leaves and twigs of M. pyrrhocarpa were isolated and purified using chromatography techniques. These extracts and pure compounds were tested in vitro for their inhibitory activities against nine strains of bacteria, as well as their anti-HIV-1 virus activity and cytotoxicity against eight cancer cell lines.

RESULTS

Three rotenoids, named 6aS, 12aS, 12S-elliptinol (1), 6aS, 12aS, 12S-munduserol (2), dehydromunduserone (3), and crude extracts were evaluated for antibacterial, anti-HIV, and cytotoxic activities. It was found that compounds 1-3 inhibited the growth of nine strains of bacteria, and the best MIC/MBC values were obtained at 3/ > 3 mg/mL. The hexane extract showed anti-HIV-1 RT with the highest %inhibition at 81.27 at 200 mg/mL, while 6aS, 12aS, 12S-elliptinol (1) reduced syncytium formation in 1A2 cells with a maximum EC₅₀ value of 4.48 μM. Furthermore, 6aS, 12aS, 12S-elliptinol (1) showed cytotoxicity against A549 and Hep G2 cells with maximum ED₅₀ values of 2.27 and 3.94 μg/mL.

CONCLUSION

This study led to the isolation of constituents with potential for medicinal application, providing compounds (1-3) as lead compounds against nine strains of bacteria. The hexane extract showed the highest %inhibition of HIV-1 virus, Compound 1 showed the best EC₅₀ in reducing syncytium formation in 1A2 cells, and it also showed the best ED₅₀ against human lung adenocarcinoma (A549) and human hepatocellular carcinoma (Hep G2). The isolated compounds from M. pyrrhocarpa offered significant potential for future medicinal application studies.

Octyl gallate targeting the 3C-like protease exhibits highly efficient antiviral activity against swine enteric coronavirus PEDV

Infection with porcine epidemic diarrhea virus (PEDV) causes severe watery diarrhea in newborn piglets, leading to substantial financial losses for the swine industry. In this study, we screened small molecule drugs targeting 3 C-like protease (3CLpro) by molecular docking, and further evaluated the antiviral activity of the screened drugs against PEDV. Results showed that octyl gallate (OG), a widely used food additive, exhibited strong binding affinity with the 3CLpro active sites of PEDV. Bio-layer interferometry and fluorescence resonance energy transfer revealed that OG directly interacts with PEDV 3CLpro (KD = 549 nM) and inhibits 3CLpro activity (IC₅₀ = 22.15 µM). OG showed a strong inhibition of PEDV replication in vitro. Virus titers were decreased by 0.58 and 0.71 log₁₀ TCID₅₀/mL for the CV777 and HM2017 strains, respectively. In vivo, all piglets in the PEDV-infected group died at 48 h post-infection (hpi), while 75% of piglets in the OG treatment group showed significant relief from the clinical symptoms, pathological damage, and viral loads in the jejunum and ileum. Moreover, the western blotting results showed that OG also has strong antiviral activity against other swine enteric coronaviruses, including transmissible gastroenteritis virus (TGEV), porcine deltacoronavirus (PDCoV), and swine acute diarrhea syndrome coronavirus (SADS-CoV). Our findings revealed that OG could be developed as a novel antiviral drug against PEDV. The OG exhibited a potential broad-spectrum antiviral drug for control of other swine enteric coronaviruses.

Pharmacological and phytochemical potential of Rubus ellipticus: a wild edible with multiple health benefits

OBJECTIVES

Rubus ellipticus (family Rosaceae) is used for its delicious edible fruits in the Himalayan region and other parts of the globe. However, the full potential of the species is yet to be harnessed. The current review focuses on the phytochemical, traditional uses, morphological, molecular and pharmacological potential of R. ellipticus.

KEY FINDINGS

The review of the literature reveals that many health-promoting compounds of R. ellipticus have been reported from the species along with the different biological properties, such as nephroprotective, anti-inflammatory, analgesic, anti-pyretic, anti-proliferative, cytotoxicity, anti-cancer, wound healing, anti-fertility, anti-plasmodial, anti-microbial and antioxidant. Traditionally, it is used in many formulations, which are validated through primary pharmacological assays. However, several medicinal properties are still need to be validated through detailed pharmacological and clinical studies.

SUMMARY

All the information is available in a scanty form, and the complete information is missing on a single platform. Such type of information will help researchers to better utilize the available data for initiating future research on the species as it has the potential to contribute to the food and pharmaceutical industry. The review highlights the need for further studies on the species to harness its potential in nutraceutical, functional food, energy supplement, and beneficial therapeutic drug development program.

Antihelminthic Activity of Lophira Lanceolata on Heligmosomoides polygyrus Using an Automated High-Throughput Method

Background

There are about 13 parasitic infections that are responsible for significant morbidity and mortality but have not received the attention they deserve; thus, they are now known as "neglected tropical diseases" (NTDs). This study was aimed at evaluating the antihelminthic activities of Lophira lanceolata using an automated high-throughput method.

Methods

The antihelminthic activity effect of the extracts against H. polygyrus was determined using an automated high-throughput method. For the egg-hatching test, 100 μL of embryonated egg suspension (60 eggs) was added to 100 μL of various concentrations of extracts, levamisole, and 1.5% DMSO in a 96-well round-bottom microtitre plate. After mixing, the 96-well microplate was placed in WMicroTracker and incubated for 24 h at 25°C; the movements were recorded every 30 minutes. The same procedure was used for the larval motility assays, where 100 μL of L1 or L2 larvae (50 larvae) were put in contact with 100 μL of various concentrations of extracts.

Results

The ovicidal activity (hatching) had an IC₅₀ of 1.4 mg/mL for the ethanol extract. The aqueous and ethanol extracts of L. lanceolata showed larvicidal activity on the L1 larvae with IC₅₀ of 1.85 mg/mL and 2.4 mg/mL, respectively, as well as on the L2 larvae with IC₅₀ values of 1.08 mg/mL and 1.02 mg/mL for the aqueous and ethanol extracts, respectively. These results showed that the aqueous extract exhibited a stronger inhibitory power on the hatching rate of parasites than ethanol extracts, while the contrary effect was observed for the larval motility assays.

Conclusion

This study provides scientific data on the use of L. lanceolata by the local population for the treatment of helminthiases. However, in vivo and toxicity tests are necessary to assess its activity and safety.

Laboratory Diagnostic Methods and Antibiotic Resistance Patterns of Staphylococcus aureus and Escherichia coli Strains: An Evolving Human Health Challenge

Raw ground meat is known as a transmission vehicle for biological agents that may be harmful to human health. The objective of the present study was to assess microbiological quality of the ground meats. A total of 280 samples of local and imported chilled meats were randomly collected from retail shops in Buraydah City, Saudi Arabia. The meat samples were microbiologically analyzed using standard methods, peptide mass fingerprinting (PMF) technique, MicroScan Walkaway System (MicroScan) and qPCR System. The imported meat was more bacterially contaminated than local meat, with variable contamination degrees of Staphylococcus aureus (40.33%), Escherichia coli (36.13%), Hafnia alvei (7.56%), Pseudomonas spp. (6.72%), Salmonella spp. (5.88%) and Aeromonas spp. (3.36%). PMF verified all the isolated bacteria by 100%, compared to 75-95% achieved by MicroScan. The gene encoding flagellin (fliC) was recognized in 67.44% of E. coli strains, while the thermonuclease (nuc) and methicillin resistance (mecA) genes were detected in 100% S. aureus and 39.6% of methicillin-resistant S. aureus (MRSA) strains, respectively. The S. aureus and E. coli strains were highly resistant to multiple antibiotics (e.g., ampicillin, amoxicillin-clavulanic acid and cephalothin). For identifying various foodborne pathogens, PMF has been recognized as a powerful and precise analytical method. In light of the increasing use of PMF to detect multidrug-resistant bacteria, this study emphasizes the need for improved ways of treating and preventing pathogens, as well as setting up monitoring systems to guarantee hygiene and safety in meat production.

Ethnobotanical study of Hakka traditional medicine in Ganzhou, China and their antibacterial, antifungal, and cytotoxic assessments

Background

Traditional herbs played a crucial role in the health care of the Hakka people. However, studies to identify these traditional herbs are few. Here we document and assess the potential of these plants for treating microbial infections. Many herbs used by the Hakka people could potentially be a novel medicinal resource.

Methods

Local herb markets were surveyed via semi-structured interviews, complemented by direct observations to obtain information on herbal usage. For each herb selected for this study, extracts in four different solvents were prepared, and tested for activity against 20 microorganisms, as well as cancerous and noncancerous cells. All data were subjected to cluster analysis to discover relationships among herbs, plant types, administration forms, solvents, microorganisms, cells, etc., with the aim to discern promising herbs for medicine.

Results

Ninety-seven Hakka herbs in Ganzhou were documented from 93 plants in 62 families; most are used for bathing (97%), or as food, such as tea (32%), soup (12%), etc. Compared with the Chinese Pharmacopoeia and Chinese Materia Medica, 24 Hakka medicines use different plant parts, and 5 plants are recorded here for the first time as traditional medicines. The plant parts used were closely related with the life cycle: annual and perennial herbs were normally used as a whole plant, and woody plants as (tender) stem and leaf, indicating a trend to use the parts that are easily collected. Encouragingly, 311 extracts (94%) were active against one or more microorganisms. Most herbs were active against Gram-positive bacteria, such as Staphylococcus aureus (67%), Listeria innocua (64%), etc. Cytotoxicity was often observed against a tumor cell, but rarely against normal cells. Considering both antimicrobial activity and cytotoxicity, many herbs reported in this study show promise as medicine.

Conclusion

Hakka people commonly use easily-collected plant parts (aerial parts or entire herb) as medicine. External use of decoctions dominated, and may help combating microbial infections. The results offer promising perspectives for further research since little phytopharmacology and phytochemistry has been published to date.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03712-z.

Phytochemical Screening, Antibacterial, Antifungal, and Anthelmintic Activity Against Plant Pathogens of two Algerian Plants: Pergularia tomentosa L. and Forsskaolea tenacissima L. from Oued Mzab (Northern Algerian Sahara)

Background:

Plants are an abundant natural source of potential chemical compounds; they have been widely used in various industries, such as pharmaceuticals, cosmetics, and food. This work aims to study two Saharan medicinal plants by evaluating the activity of plant extract against bacterial and fungal plant pathogens as well as against the model nematode Caenorhabditis (C.) elegans.

Methods:

The antimicrobial activity of plant extracts against plants pathogen was assessed in a 96- well plate assay by calculating the percentage of inhibition of bacteria. The antifungal activity against plant pathogenic fungi was evaluated by the agar diffusion method, and inhibition was calculated by measuring the diameter of the inhibition zone. Anthelmintic activity was evaluated by calculating the average movement of C. elegans worms. Preliminary phytochemical screening was realized with HPTLC.

Results:

Hexane and ethyl acetate extract of Pergularia tomentosa showed broad-spectrum antimicrobial activity. This plant has the potential to act as a broad-spectrum antibacterial biopesticide. Hexane extract of Forsskaolea tenacissima exhibited good activity against one fungus. The extracts of Pergularia tomentosa showed good activity against Caenorhabditis elegans, and the extracts of Forsskaolea tenacissima exhibited a low activity. Preliminary phytochemical screening with HPTLC shows that both plants are rich in steroids and flavonoids.

Conclusion:

Our study shows that the studied plants may possess a broad-spectrum antibacterial effect with narrow-spectrum antifungal properties which can offer more sustainable crop protection with a much safer environmental and human health impact. Plant extracts that inhibited C. elegans could provide a starting point for the development of new anthelmintic drugs.

Ethnomedicinal study of medicinal plants used by Mizo tribes in Champhai district of Mizoram, India

BACKGROUND

Medicinal plants have been used countless times for curing diseases mainly in developing countries. They are easily available with little to no side effects when compared to modern medicine. This manuscript encompasses information on ethnomedicinal plants in Champhai district, located in the North East Region (NER) of India. The region lies within Indo-Burma biodiversity hotspot. This study will be the first quantitative report on the ethnomedicinal plants used by the local tribes of this region. Knowledge of medicinal plants is mostly acquired by word of mouth, and the knowledge is dying among the local youths with the prevalence of modern medicine. Hence, there is urgency in deciphering and recording such information.

METHODS

Information was gathered through interviews with 200 informants across 15 villages of the Champhai district. From the data obtained, we evaluate indices such as used report (UR), frequency of citation (FC), informant consensus factor (Fic), cultural values (CVs) and relative importance (RI) for all the plant species. Secondary data were obtained from scientific databases such as Pubmed, Sci Finder and Science Direct. The scientific name of the plants was matched and arranged in consultation with the working list of all plant species ( http://www.theplantlist.org ).

RESULTS

Totally, 93 plant species from 53 families and 85 genera were recorded. The most common families are Euphorbiaceae and Asteraceae with six and five species representatives, respectively. Leaves were the most frequently used part of a plant and were usually used in the form of decoction. Curcuma longa has the most cultural value (27.28 CVs) with the highest used report (136 FC), and the highest RI value was Phyllanthus emblica. The main illness categories as per Frequency of citation were muscle/bone problem (0.962 Fic), gastro-intestinal disease (0.956 Fic) and skin care (0.953 Fic).

CONCLUSION

The people of Mizoram living in the Champhai district have an immense knowledge of ethnomedicinal plants. There were no side effects recorded for consuming ethnomedicinal plants. We observed that there is a scope of scientific validation of 10 plant species for their pharmacological activity and 13 species for the phytochemical characterisation or isolation of the phytochemicals. This might pave the path for developing a scientifically validated botanical or lead to semisyntheic derivatives intended for modern medicine.

Leaf Extract and Active Fractions of Dillenia pentagyna Roxb. Reduce In Vitro Human Cancer Cell Migration Via NF-κB Pathway

Background:

Different parts of Dillenia pentagyna have long been used in traditional medicines to cure several diseases including cancer. However, the mechanism(s) of anti-cancer effects are still unknown. We aimed to elucidate the anti-metastatic potential of ethanolic extracts of leaves of D. pentagyna (EELDP) and active fractions of it in highly metastatic human cancer cells.

Methods:

We screened different HPLC fractions of EELDP based on their anti-metastatic effect. We used TLC and ESI-MS for determining the presence of various phytochemicals in EELDP and fractions. We monitored in vitro anti-metastasis effect of EELDP (0-0.6 mg/ml) and active fractions (0-0.050 mg/ml) on various human cancer cells like A549, HeLa, and U2OS.

Results:

EELDP significantly reduced cell viability and cell migration in A549, HeLa, and U2OS cells. However, higher sensitivity was observed in A549 cells. We screened 2 active HPLC fractions F6 and F8 having anti-MMPs activity. EELDP and active fractions reduced metastasis via the NF-κB pathway, decreased the expression of Vimentin, N-cadherin, and increased the expression of Claudin-1.

Conclusion:

Significant reduction of metastasis by EELDP at a dose of 0.1 mg/ml or by active fractions at 0.050 mg/ml implicates that the active compound(s) present in crude or fractions are extremely potent to control highly metastatic cancer.

In-vitro examination and isolation of antidiarrheal compounds using five bacterial strains from invasive species Bidens bipinnata L

Bidens bipinnata is widely utilized medicinal plant for treatment of diseases like malaria, sore throat, acute nephritis and dysentery. However, despite its traditional uses Bidens bipinnata is not widely explored for its antimicrobial effect. Thus, the current study is aimed to form antimicrobial activity report of Bidens bipinnata extracts, along with isolation and evaluation of antibacterial activity of the isolated compounds through bioassay-guided purification. Hexane extract of its leaves has appeared to be most active thus it is exposed to automated column chromatography. Further purification using High-performance liquid chromatography has led to isolation of active peaks, identified by Gas Chromatography-mass spectrometry, as 16-Pregnenolone and 9-Octadecenoic acid (Z)-, methyl ester. Their antimicrobial activity was confirmed via broth dilution procedure on Staphylococcus aureus, 16-Pregnenolone revealed a strong antimicrobial activity with MIC₅₀ of 72 μg/mL whereas 9-Octadecenoic acid (Z)-, methyl ester display an MIC₅₀ of >250 μg/mL. Present study is the first report on isolation of these compounds from Bidens bipinnata.

Cellulose extraction of Alstonia scholaris: A comparative study on efficiency of different bleaching reagents for its isolation and characterization

The incredible benefits of Alstonia scholaris are piquing researchers' attention in extracting its cellulose and utilizing it in further therapeutic applications. This study is based on cellulose extraction from its stalks and processed through chemical pre-treatments to manifest its cellulose content by using different bleaching reagents. A comparison was made on efficiencies of three reagents and it is found that the hydrogen peroxide exposed maximum cellulose than sodium hypochlorite and sodium chlorite. The experimental results revealed that A. scholaris possess 68-70% cellulose content. FTIR spectrum shows that OH- and CH- vibrations of cellulose appeared at 3320 cm^-1 & 2892 cm^-1 respectively whereas SEM images show fibrillation, rough surface, and lumens in bleached fiber that attributes to the removal of lignin and hemicelluloses and confirms cellulose extraction. The XRD pattern certifies the crystalline nature and compactness of cellulose whereas tensile properties and TGA help in understanding its flexibility, mechanical strength, and thermal stability at 370 °C respectively.

A Review of Medicinal Plants with Antiviral Activity Available in Bangladesh and Mechanistic Insight Into Their Bioactive Metabolites on SARS-CoV-2, HIV and HBV

Currently, viral infection is the most serious health issue which causing unexpected higher rate of death globally. Many viruses are not yet curable, such as corona virus-2 (SARS-CoV-2), human immunodeficiency virus (HIV), hepatitis virus, human papilloma virus and so others. Furthermore, the toxicities and ineffective responses to resistant strains of synthetic antiviral drugs have reinforced the search of effective and alternative treatment options, such as plant-derived antiviral drug molecules. Therefore, in the present review, an attempt has been taken to summarize the medicinal plants reported for exhibiting antiviral activities available in Bangladesh along with discussing the mechanistic insights into their bioactive components against three most hazardous viruses, namely SARS-CoV-2, HIV, and HBV. The review covers 46 medicinal plants with antiviral activity from 25 families. Among the reported 79 bioactive compounds having antiviral activities isolated from these plants, about 37 of them have been reported for significant activities against varieties of viruses. Hesperidin, apigenin, luteolin, seselin, 6-gingerol, humulene epoxide, quercetin, kaempferol, curcumin, and epigallocatechin-3-gallate (EGCG) have been reported to inhibit multiple molecular targets of SARS-CoV-2 viral replication in a number of in silico investigations. Besides, numerous in silico, in vitro, and in vivo bioassays have been demonstrated that EGCG, anolignan-A, and B, ajoene, curcumin, and oleanolic acid exhibit anti-HIV activity while piperine, ursolic acid, oleanolic acid, (+)-cycloolivil-4'-O-β-d-glucopyranoside, quercetin, EGCG, kaempferol, aloin, apigenin, rosmarinic acid, andrographolide, and hesperidin possess anti-HBV activity. Thus, the antiviral medicinal plants and the isolated bioactive compounds may be considered for further advanced investigations with the aim of the development of effective and affordable antiviral drugs.

Using HPLC-DAD and GC-MS Analysis Isolation and Identification of Anticandida Compounds from Gui Zhen Cao Herbs (Genus Bidens): An Important Chinese Medicinal Formulation

Gui Zhen Cao is an herbal formulation that has been documented in Chinese traditional medicine as a remedy for diarrhea, dysentery, inflammation, and toxicity. The sources of this formulation (Bidens pilosa L., Bidens biternata (Lour.) Merr. & Sherff, Bidens bipinnata L.) are also listed in ethnomedicinal reports all over the world. In this study, all these plants are tested for in vitro anticandida activity. A quantitative evaluation of the phytochemicals in all these plants indicated that their vegetative parts are rich in tannins, saponins, oxalates, cyanogenic glycoside and lipids; moreover, the roots have high percentages of alkaloids, flavonoids, and phenols. The results indicated significant anticandida activity, especially for the hexane extract of B. bipinnata leaves which inhibited C. albicans (42.54%), C. glabrata (46.98%), C. tropicalis (50.89%), C. krusei (40.56%), and C. orthopsilosis (50.24%). The extract was subjected to silica gel chromatography and 220 fractions were obtained. Purification by High Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) and Gas Chromatography tandem Mass Spectrometry (GC-MS/MS) analysis led to the identification of two anticandida compounds: dehydroabietic and linoleic acid having an inhibition of 85 and 92%, respectively.

Herbal plants as immunity modulators against COVID-19: A primary preventive measure during home quarantine

The novel coronavirus or severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is a deadly virus which has spread globally and claimed millions of lives. This novel virus transmits mainly through droplets and close human contact. It’s impact in different countries varies depending on geographical location, climatic conditions, food habits, and cultural activities. Several precautionary measures, as well as many medicines, are applied in different combinations to limit the spread of infection. This results in a preliminary relief of people infected in the first stage of infection. An alternative approach has been introduced which proposes natural herbs, which have minimal or no side effects, and improve overall immunity. Some essential herbs with their immunomodulatory effects are mentioned in this article along with suggestions for improved immunity and protection.

A High-Throughput Metabolic Microarray Assay Reveals Antibacterial Effects of Black and Red Raspberries and Blackberries against Helicobacter pylori Infection

Helicobacter pylori infection is commonly treated with a combination of antibiotics and proton pump inhibitors. However, since H. pylori is becoming increasingly resistant to standard antibiotic regimens, novel treatment strategies are needed. Previous studies have demonstrated that black and red berries may have antibacterial properties. Therefore, we analyzed the antibacterial effects of black and red raspberries and blackberries on H. pylori. Freeze-dried powders and organic extracts from black and red raspberries and blackberries were prepared, and high-performance liquid chromatography was used to measure the concentrations of anthocyanins, which are considered the major active ingredients. To monitor antibiotic effects of the berry preparations on H. pylori, a high-throughput metabolic growth assay based on the Biolog system was developed and validated with the antibiotic metronidazole. Biocompatibility was analyzed using human gastric organoids. All berry preparations tested had significant bactericidal effects in vitro, with MIC₉₀ values ranging from 0.49 to 4.17%. Antimicrobial activity was higher for extracts than powders and appeared to be independent of the anthocyanin concentration. Importantly, human gastric epithelial cell viability was not negatively impacted by black raspberry extract applied at the concentration required for complete bacterial growth inhibition. Our data suggest that black and red raspberry and blackberry extracts may have potential applications in the treatment and prevention of H. pylori infection but differ widely in their MICs. Moreover, we demonstrate that the Biolog metabolic assay is suitable for high-throughput antimicrobial susceptibility screening of H. pylori.

Practical High-Throughput Method to Screen Compounds for Anthelmintic Activity against Caenorhabditis elegans

In the present study, we established a practical and cost-effective high throughput screening assay, which relies on the measurement of the motility of Caenorhabditis elegans by infrared light-interference. Using this assay, we screened 14,400 small molecules from the "HitFinder" library (Maybridge), achieving a hit rate of 0.3%. We identified small molecules that reproducibly inhibited the motility of C. elegans (young adults) and assessed dose relationships for a subset of compounds. Future work will critically evaluate the potential of some of these hits as candidates for subsequent optimisation or repurposing as nematocides or nematostats. This high throughput screening assay has the advantage over many previous assays in that it is cost- and time-effective to carry out and achieves a markedly higher throughput (~10,000 compounds per week); therefore, it is suited to the screening of libraries of tens to hundreds of thousands of compounds for subsequent evaluation and development. The present phenotypic whole-worm assay should be readily adaptable to a range of socioeconomically important parasitic nematodes of humans and animals, depending on their dimensions and motility characteristics in vitro, for the discovery of new anthelmintic candidates. This focus is particularly important, given the widespread problems associated with drug resistance in many parasitic worms of livestock animals globally.

High-Throughput Phenotypic Assay to Screen for Anthelmintic Activity on Haemonchus contortus

Parasitic worms cause very significant diseases in animals and humans worldwide, and their control is critical to enhance health, well-being and productivity. Due to widespread drug resistance in many parasitic worms of animals globally, there is a major, continuing demand for the discovery and development of anthelmintic drugs for use to control these worms. Here, we established a practical, cost-effective and semi-automated high throughput screening (HTS) assay, which relies on the measurement of motility of larvae of the barber’s pole worm (Haemonchus contortus) using infrared light-interference. Using this assay, we screened 80,500 small molecules and achieved a hit rate of 0.05%. We identified three small molecules that reproducibly inhibited larval motility and/or development (IC₅₀ values of ~4 to 41 µM). Future work will critically assess the potential of selected hits as candidates for subsequent optimisation or repurposing against parasitic nematodes. This HTS assay has a major advantage over most previous assays in that it achieves a ≥ 10-times higher throughput (i.e., 10,000 compounds per week), and is thus suited to the screening of libraries of tens of thousands to hundreds of thousands of compounds for subsequent hit-to-lead optimisation or effective repurposing and development. The current assay should be adaptable to many socioeconomically important parasitic nematodes, including those that cause neglected tropical diseases (NTDs). This aspect is of relevance, given the goals of the World Health Organization (WHO) Roadmap for NTDs 2021–2030, to develop more effective drugs and drug combinations to improve patient outcomes and circumvent the ineffectiveness of some current anthelmintic drugs and possible drug resistance.

Bioassay-guided isolation of antibacterial compounds from the leaves of Tetradenia riparia with potential bactericidal effects on food-borne pathogens

ETHNOPHARMACOLOGICAL RELEVANCE

Tetradenia riparia (commonly known as ginger bush) is frequently used in traditional African medicine to treat foodborne infections including diarrhoea, gastroenteritis, and stomach ache.

AIM OF THE STUDY

The present study aims to identify in Tetradenia riparia the compounds active against foodborne pathogens.

MATERIALS AND METHODS

Dried Tetradenia riparia leaf powder was consecutively extracted with hexane, ethyl acetate, methanol and water. The hexane extract was counter-extracted with methanol:water (9:1), and after evaporation of the methanol, this phase was extracted with dichloromethane. The water extract was counter-extracted with butanol. All these fractions were tested against a panel of foodborne bacterial pathogens. A bioassay-guided purification was performed to isolate antimicrobial compounds using Staphylococcus aureus as a target organism. Further, antibiofilm activity was evaluated on S. aureus USA 300.

RESULTS

The dichloromethane fraction and ethyl acetate extract were the most potent, and therefore subjected to silica gel chromatography. From the dichloromethane fraction, one active compound was crystalized and identified using NMR as 8(14),15-sandaracopimaradiene-7alpha, 18-diol (compound 1). Two active compounds were isolated from the ethyl acetate extract: deacetylumuravumbolide (compound 2) and umuravumbolide (compound 3). Using a microdilution method, their antimicrobial activity was tested against eight foodborne bacterial pathogens: Shigella sonnei, S. flexneri, Salmonella enterica subsp. enterica, Escherichia coli, Micrococcus luteus, S. aureus, Enterococcus faecalis, and Listeria innocua. Compound 1 had the strongest activity (IC₅₀ ranging from 11.2 to 212.5 μg/mL), and compounds 2 and 3 showed moderate activity (IC₅₀ from 212.9 to 637.7 μg/mL and from 176.1 to 521.4 μg/mL, respectively). Interestingly, 8(14),15-sandaracopimaradiene-7alpha, 18-diol is bactericidal, and also showed good antibiofilm activity with BIC₅₀ (8.8 ± 1.5 μg/mL) slightly lower than for planktonic cells (11.4 ± 2.8 μg/mL).

CONCLUSIONS

These results support the traditional use of this plant to conserve foodstuffs and to treat gastrointestinal ailments, and open perspectives for its use in the prevention and treatment of foodborne diseases.

In Vitro and In Silico Cytotoxic and Antibacterial Activities of a Diterpene from Cousinia alata Schrenk

A biologically guided isolation of secondary metabolites from Cousinia alata Schrenk wild plant growing in Akmola region, Kazakhstan, led to the isolation of the bioactive diterpene grindelic acid (1). Six flavonoids were also isolated and identified as retusine (2), pachipodol (3), jaranol (4), penduletin (5), casticin (6), and 5, 7, 3′-trihydroxy-3, 4′-dimethoxyflavone (7). Penduletin (5) showed moderate cytotoxic activity assay. Grindelic acid exhibited promising cytotoxic activity against the Artemia salina nauplii and antibacterial activity against Staphylococcus aureus, Bacillus cereus, and Salmonella enteritidis. The presence of the essential pharmacophoric features of histone deacetylase (HDAC) inhibitors in the structure of grindelic acid encouraged us to run a molecular docking study against the HDAC enzyme to understand its mechanism of action on a molecular level. Grindelic acid showed a binding mode of interaction similar to that of the cocrystallized ligand and exhibited good binding affinity against HDAC with the binding free energy of −18.70 kcal/mol. The structures of isolated compounds were determined by MS, 1D, and 2D NMR spectroscopy methods. Compounds (1–7) were isolated for the first time from Cousinia genus.

Plant Products as Inhibitors of Coronavirus 3CL Protease

Background: The ongoing COVID-19 pandemic has created an alarming situation due to extensive loss of human lives and economy, posing enormous threat to global health security. Till date, no antiviral drug or vaccine against SARS-CoV-2 has reached the market, although a number of clinical trials are under way. The viral 3-chymotrypsin-like cysteine protease (3CLpro), playing pivotal roles in coronavirus replication and polyprotein processing, is essential for its life cycle. In fact, 3CLpro is already a proven drug discovery target for SARS- and MERS-CoVs. This underlines the importance of 3CL protease in the design of potent drugs against COVID-19. Methods: We have collected one hundred twenty-seven relevant literatures to prepare the review article. PubMed, Google Scholar and other scientific search engines were used to collect the literature based on keywords, like "SARS-CoVs-3CL protease," "medicinal plant and anti-SARS-CoVs-3CL protease" published during 2003-2020. However, earlier publications related to this topic are also cited for necessary illustration and discussion. Repetitive articles and non-English studies were excluded. Results: From the literature search, we have enlisted medicinal plants reported to inhibit coronavirus 3CL protease. Some of the plants like Isatis tinctoria L. (syn. Isatis indigotica Fort.), Torreya nucifera (L.) Siebold and Zucc., Psoralea corylifolia L., and Rheum palmatum L. have exhibited strong anti-3CLpro activity. We have also discussed about the phytochemicals with encouraging antiviral activity, such as, bavachinin, psoralidin, betulinic acid, curcumin and hinokinin, isolated from traditional medicinal plants. Conclusion: Currently, searching for a plant-derived novel drug with better therapeutic index is highly desirable due to lack of specific treatment for SARS-CoV-2. It is expected that in-depth evaluation of medicinally important plants would reveal new molecules with significant potential to inhibit coronavirus 3CL protease for development into approved antiviral drug against COVID-19 in future.

Indian Medicinal Plants and Formulations and Their Potential Against COVID-19-Preclinical and Clinical Research

The cases of COVID-19 are still increasing day-by-day worldwide, even after a year of its first occurrence in Wuhan city of China. The spreading of SARS-CoV-2 infection is very fast and different from other SARS-CoV infections possibly due to structural differences in S proteins. The patients with severe diseases may die due to acute respiratory distress syndrome (ARDS) caused by systemic inflammatory reactions due to the excessive release of pro-inflammatory cytokines and chemokines by the immune effector cells. In India too, it is spreading very rapidly, although the case fatality rate is below 1.50% (https://www.statista.com), which is markedly less than in other countries, despite the dense population and minimal health infrastructure in rural areas. This may be due to the routine use of many immunomodulator medicinal plants and traditional AYUSH formulations by the Indian people. This communication reviews the AYUSH recommended formulations and their ingredients, routinely used medicinal plants and formulations by Indian population as well as other promising Indian medicinal plants, which can be tested against COVID-19. Special emphasis is placed on Indian medicinal plants reported for antiviral, immunomodulatory and anti-allergic/anti-inflammatory activities and they are categorized for prioritization in research on the basis of earlier reports. The traditional AYUSH medicines currently under clinical trials against COVID-19 are also discussed as well as furtherance of pre-clinical and clinical testing of the potential traditional medicines against COVID-19 and SARS-CoV-2. The results of the clinical studies on AYUSH drugs will guide the policymakers from the AYUSH systems of medicines to maneuver their policies for public health, provide information to the global scientific community and could form a platform for collaborative studies at national and global levels. It is thereby suggested that promising AYUSH formulations and Indian medicinal plants must be investigated on a priority basis to solve the current crisis.

A review on genus Millettia: Traditional uses, phytochemicals and pharmacological activities

The genus Millettia belongs to Fabaceae includes 200 species which are distributed in tropical and subtropical regions of the world. Plants belong to this genus are used as folkloric medicine, for the treatment of different ailments like in wound healing, boil, sores, skin diseases, snake bite, muscle aches, pains, rheumatic arthritis, and gynaecological diseases. The aim of the review is to provide updated, comprehensive and categorized information on the aspects of ethnobotanical, phytochemical, pharmacological uses and toxicity of genus Millettia in order to identify their therapeutic potential and generate space for future research opportunities. The present study comprises of isolated flavonoids, phenolic compounds, phytosterols, saponins, alkaloids, polysaccharides, terpenoids and resins and pharmacological activities of various Millettia species. The relevant data were searched by using the keyword “Millettia” in different scientific databases like, “Google Scholar”; “NISCAIR repository”; “Pub Med”; “Science Direct”; “Scopus” and the taxonomy is validated by “The Plant List”. This review discusses the existing information of the traditional evaluation as well as phytochemical and pharmacological evaluation of the extract and active constituents of the genus “Millettia”. This review confirms that several Millettia species have emerged as a high-quality medicine in a traditional system for arthritis, wound healing, inflammation, skin diseases. Numerous conventional uses of Millettia species have been validated by modern pharmacology research. Intensive investigations of the genus Millettia relating to phytochemistry and pharmacology, especially their mechanism of action, safety, and efficacy could be the future research interests by the researcher in the area of phytomedicine.

Metabolic Diversity and Therapeutic Potential of Holarrhena pubescens: An Important Ethnomedicinal Plant

Holarrhena pubescens is an important medicinal plant of the Apocynaceae family that is widely distributed over the Indian subcontinent. The plant is extensively used in Ayurveda and other traditional medicinal systems without obvious adverse effects. Beside notable progress in the biological and phytochemical evaluation of this plant over the past few years, comprehensive reviews of H. pubescens are limited in scope. It has economic importance due to the extensive use of seeds as an antidiabetic. Furthermore, the plant is extensively reported in traditional uses among the natives of Asia and Africa, while scientifical validation for various ailments has not been studied either in vitro or in vivo. This review aims to summarize information on the pharmacology, traditional uses, active constituents, safety and toxicity of H. pubescens. Chemical analysis of H. pubescens extracts revealed the presence of several bioactive compounds, such as conessine, isoconnessine, conessimine, conimine, conessidine, conkurchicine, holarrhimine, conarrhimine, mokluangin A-D and antidysentericine. Overall, this review covers the ethnopharmacology, phytochemical composition, and pharmacological potential of H. pubescens, with a critical discussion of its toxicity, biological activities (in vitro and in vivo), the mechanism of action, as well as suggestions for further basic and clinical research.

Nematicidal Activity of Holigarna caustica (Dennst.) Oken Fruit Is Due to Linoleic Acid

Holigarna caustica (Dennst.) Oken is used by the tribes of Northeast India for the treatment of intestinal problems. Therefore, the present study was undertaken to investigate the active principles of this plant responsible for its anthelmintic activity, using bioassay-guided fractionation. An ethanol extract of H. caustica fruit was fractionated on a silica gel column, followed by HPLC, while nematicidal activity was followed throughout on Caenorhabditis (C.) elegans as a model organism. Our study constitutes the first nematicidal report for this plant. Bioassay-guided purification led to the isolation of one compound (IC₅₀ = 0.4 µM) as the only active constituent in the most active fraction. The compound was identified as linoleic acid based on spectroscopic data (¹H and ¹³C NMR and ESI-MS). No cytotoxicity was observed in the crude extract or in linoleic acid (up to 356 µM). The results support the use of H. caustica for the treatment of intestinal problems by traditional healers in India.

Comprehensive Characterization of Secondary Metabolites from Colebrookea oppositifolia (Smith) Leaves from Nepal and Assessment of Cytotoxic Effect and Anti-Nf-κB and AP-1 Activities In Vitro

Here we report the comprehensive characterization of the secondary metabolites from the leaves of Colebrookea oppositifolia Smith, a species used as medicinal plant in the traditional medicine of Nepal. Phytochemical screening of bioactives was performed using an integrated LC-MSⁿ and high resolution MS (Mass Spectrometry) approach. Forty-three compounds were tentatively identified, mainly aglyconic and glycosilated flavonoids and phenolic acids, as well as other bioactives such as coumarins and terpenes were detected. Furthermore, the NF-κB and AP-1 inhibitory activity of C. oppositifolia extract were evaluated, as well as its cytotoxicity against THP-1 cells, in order to assess the potential use of this herb as a source of anti-inflammatory and cytotoxic compounds. The results so far obtained indicate that C. oppositifolia leaves extract could significantly reduce the viability of THP-1 cells (IC₅₀ = 6.2 ± 1.2 µg/mL), as well as the activation of both NF-κB and AP-1 at the concentration of 2 μg/mL. Our results indicate that Nepalese C. oppositifolia is a valuable source of anti-inflammatory and cytotoxic compounds. The phytochemical composition reported here can partially justify the traditional uses of C. oppositifolia in Nepal, especially in the treatment of inflammatory diseases, although further research will be needed to assess the full potential of this species.

Antiviral and Cytotoxic Activity of Different Plant Parts of Banana (Musa spp.)

Chikungunya and yellow fever virus cause vector-borne viral diseases in humans. There is currently no specific antiviral drug for either of these diseases. Banana plants are used in traditional medicine for treating viral diseases such as measles and chickenpox. Therefore, we tested selected banana cultivars for their antiviral but also cytotoxic properties. Different parts such as leaf, pseudostem and corm, collected separately and extracted with four different solvents (hexane, acetone, ethanol, and water), were tested for in vitro antiviral activity against Chikungunya virus (CHIKV), enterovirus 71 (EV71), and yellow fever virus (YFV). Extracts prepared with acetone and ethanol from leaf parts of several cultivars exhibited strong (EC₅₀ around 10 μg/mL) anti-CHIKV activity. Interestingly, none of the banana plant extracts (concentration 1–100 µg/mL) were active against EV71. Activity against YFV was restricted to two cultivars: Namwa Khom–Pseudostem–Ethanol (5.9 ± 5.4), Namwa Khom–Corm–Ethanol (0.79 ± 0.1) and Fougamou–Corm–Acetone (2.5 ± 1.5). In most cases, the cytotoxic activity of the extracts was generally 5- to 10-fold lower than the antiviral activity, suggesting a reasonable therapeutic window.

Antibacterial, Antifungal, Antiviral, and Anthelmintic Activities of Medicinal Plants of Nepal Selected Based on Ethnobotanical Evidence

Background

Infections by microbes (viruses, bacteria, and fungi) and parasites can cause serious diseases in both humans and animals. Heavy use of antimicrobials has created selective pressure and caused resistance to currently available antibiotics, hence the need for finding new and better antibiotics. Natural products, especially from plants, are known for their medicinal properties, including antimicrobial and anthelmintic activities. Geoclimatic variation, together with diversity in ethnomedicinal traditions, has made the Himalayas of Nepal an invaluable repository of traditional medicinal plants. We studied antiviral, antibacterial, antifungal, and anthelmintic activities of medicinal plants, selected based upon ethnobotanical evidence.

Methods

Ethanolic and methanolic extracts were tested (1) on a panel of microbes: two Gram-positive bacteria (Staphylococcus aureus and Listeria innocua), four Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, and Shigella sonnei), and one fungal species: Candida albicans; (2) against three different viruses: yellow fever, chikungunya, and enterovirus; and (3) on the nematode Caenorhabditis elegans. Also, cytotoxicity was assessed on human hepatoma (Huh), rhabdosarcoma (RD), and Vero (VC) cell lines.

Results

Of 18 plants studied, Ampelocissus tomentosa and Aleuritopteris anceps inhibited S. aureus (MIC 35 μg/mL and 649 μg/mL, respectively) and Pseudomonas aeruginosa (MIC 15 μg/mL and 38 μg/mL, respectively). Rhododendron arboreum and Adhatoda vasica inhibited S. enterica (MIC 285 μg/mL and 326 μg/mL, respectively). Kalanchoe pinnata, Ampelocissus tomentosa, and Paris polyphylla were active against chikungunya virus, and Clerodendrum serratum was active against yellow fever virus (EC₅₀ 15.9 μg/mL); Terminalia chebula was active against enterovirus (EC₅₀ 10.6 μg/mL). Ampelocissus tomentosa, Boenninghausenia albiflora, Dichrocephala integrifolia, and Kalanchoe pinnata significantly reduced C. elegans motility, comparable to levamisole.

Conclusions

In countries like Nepal, with a high burden of infectious and parasitic diseases, and a current health system unable to combat the burden of diseases, evaluation of local plants as a treatment or potential source of drugs can help expand treatment options. Screening plants against a broad range of pathogens (bacteria, viruses, fungi, and parasites) will support bioprospecting in Nepal, which may eventually lead to new drug development.

Antimicrobial Activity of Selected Banana Cultivars Against Important Human Pathogens, Including Candida Biofilm

Ten banana (Musa spp.) cultivars were studied for their antimicrobial properties. Three plant parts (corm, pseudostem and leaves) were collected separately and extracted with different solvents, viz., hexane, acetone, ethanol and water. The 50% inhibitory concentration (IC₅₀) was evaluated using a broth microdilution assay. Eight human bacterial and one fungal pathogen were tested. Acetone and ethanol extract(s) often exhibited significant antimicrobial activity, while hexane extracts were less active. Aqueous extracts often showed microbial growth, possibly by endophytes. Leaf extracts were most active, followed by pseudostem, and corm was least active. All the tested banana cultivars were found to contain antimicrobials, as demonstrated by inhibition of selected human pathogens. However, cultivars such as Dole, Saba, Fougamou, Namwah Khom, Pelipita and Mbwazirume showed a broad-spectrum activity, inhibiting all tested pathogens. Other cultivars such as Petit Naine and Kluai Tiparot showed a narrow-spectrum activity, including antibiofilm activity against Candida albicans. Our results support the use of different parts of banana plants in traditional human medicine for infections, including diarrhea and dysentery, and some sexually transmitted diseases, as well as for packaging spoilable materials like food.

Biofilm inhibiting properties of compounds from the leaves of Warburgia ugandensis Sprague subsp ugandensis against Candida and staphylococcal biofilms

ETHNOPHARMACOLOGICAL RELEVANCE

Warburgia ugandensis Sprague subspecies ugandensis is a plant widely distributed in Eastern, Central and Southern Africa. In humans, it is used to treat respiratory infections, tooth aches, malaria, skin infections, venereal diseases, diarrhea, fevers and aches.

AIM OF THE STUDY

This study aims to identify the bioactive compounds against clinically important biofilm-forming strains of Candida and staphylococci that are responsible for tissue and implanted device-related infections.

METHODS

Using a bioassay-guided fractionation approach, hexane -, ethanol -, acetone - and water extracts from the leaves of W. ugandensis, their subsequent fractions and isolated compounds were tested against both developing and preformed 24 h-biofilms of Candida albicans SC5314, Candida glabrata BG2, Candida glabrata ATCC 2001, Staphylococcus epidermidis 1457 and Staphylococcus aureus USA 300 using microtiter susceptibility tests. Planktonic cells were also tested in parallel for comparison purposes. Confocal scanning laser microscopy was also used to visualize effects of isolated compounds on biofilm formation.

RESULTS

Warburganal, polygodial and alpha-linolenic acid (ALA) were the major bioactive compounds isolated from the acetone extract of W. ugandensis. For both warburganal and polygodial, the biofilm inhibitory concentration that inhibits 50% of C. albicans developing biofilms (BIC₅₀) was 4.5 ± 1 and 10.8 ± 5 μg/mL respectively. Against S. aureus developing biofilms, this value was 37.9 ± 8 μg/mL and 25 μg/mL with warburganal and ALA respectively. Eradication of preformed 24 h biofilms was also observed. Interestingly, synergy between the sesquiterpenoids and azoles against developing C. albicans biofilms resulted in an approximately ten-fold decrease of the effective concentration required to completely inhibit growth of the biofilms by individual compounds. The hydroxyl group in position C-9 in warburganal was identified as essential for activity against staphylococcal biofilms. We also identified additional promising bioactive sesquiterpenoids; drimenol and drimendiol from the structure-activity relationship (SAR) studies.

CONCLUSIONS

ALA and four sesquiterpenoids: polygodial, warburganal, drimenol and drimendiol, have shown biofilm-inhibitory activity that has not been reported before and is worth following up. These compounds are potential drug candidates to manage biofilm-based infections, possibly in combination with azoles.

Bauhinia holophylla (Bong.) Steud. leaves-derived extracts as potent anti-dengue serotype 2

Dengue virus (DENV) is the most prevalent mosquito-borne viral pathogen and made the disease a major health concern worldwide. However, specific antiviral drugs against this arbovirose or vaccines are not yet available for treatment or prevention. Thus, here we aimed to study the antiviral activity of hydroethanolic extract, fraction ethyl acetate and subfractions of the leaves of Bauhinia holophylla (Fabaceae:Cercideae), a native plant of the Brazilian Cerrado, against DENV-2 by methylthiazolyldiphenyl-tetrazolium bromide (MTT) method in mammalian cells culture. As results, the hydroethanolic extract showed the most potent effect, with an inhibitory concentration (IC₅₀) of 3.2 μg mL^-1 and selectivity index (SI) of 27.6, approximately 16-times higher anti-DENV-2 activity than of the ribavirin (IC₅₀ 52.8 μg mL^-1). Our results showed in this study appointed that B. holophylla has a promising anti-dengue activity, which was associated mainly with the presence of flavonoids.

Ethanolic extract of leaf of Dillenia pentagyna reduces in-vitro cell migration and induces intrinsic pathway of apoptosis via downregulation of NF-κβ in human NSCLC A549 cells

Despite the advancement of the pharmaceutical industry, medicinal plants are still a reliable source of traditional medicines to cure a number of diseases. Various parts of Dillenia pentagyna are used in traditional medicine in India for treatment of various disorders including cancers, but detailed mechanisms are still unknown. Dried leaves of D. pentagyna were extracted with ethanol and termed as an ethanolic extract of leaves of D. pentagyna (EELDP). Our aim was to elucidate the role of EELDP in in-vitro cell migration and apoptosis in highly metastatic human lung adenocarcinoma A549 cells. We measured cell viability and in-vitro cell migration in three different human cancer cells A549, HeLa and U2OS treated with EELDP (0-0.6 mg/mL). However, A549 cells showed higher sensitivity to EELDP treatment. Hence we studied several key markers of metastasis and apoptosis pathway in A549 cells treated with EELDP. EELDP treatment significantly reduced in-vitro cell migration, wound healing, expression and activity of MMP-2, MMP-9 via reduction of nuclear factor kappa Beta (NF-κβ). EELDP also reduced vimentin, N-cadherin and increased claudin-1. The intrinsic pathway of apoptosis was triggered by EELDP via the NF-κβ pathway through the increase of the Bax to Bcl₂ ratio, leading to the fall of mitochondrial membrane potential and subsequently induced release of cytochrome c, activation of caspase-3 followed by nuclear fragmentation in A549 cells. Furthermore, we observed change of a few markers of metastasis and apoptosis in other two cell types HeLa and U2OS treated with EELDP. These data implicate that the effect of EELDP is not cell-specific. Since only 0.1 mg/mL EELDP significantly reduces in-vitro cell migration and increases apoptosis, the active compound(s) present in EELDP is very much potent to control highly metastatic cancer.

Antioxidant, Cytotoxicity, and Antiophidian Potential of Alstonia macrophylla Bark

The objective of this research was to find the possible pharmacognosy of the bark of the Philippine Alstonia macrophylla Wall. ex G.Don (AM). Gas chromatographic-mass spectral (GC-EI-MS) characterization and energy dispersive X-ray spectroscopy (EDX) were performed to detect the bioactive constituents. EDX analysis of AM bark displayed a high content of potassium (3.26%) and calcium (2.96%). Eight constituents were detected in AM crude dichloromethane (DCM) extracts, which consisted of a long-chain unsaturated fatty acid (17:0) and fatty acid esters such as ethyl hexadecanoate and methyl hexadecanoate. Extraction of AM bark using methanol and dimethyl sulfoxide (MeOH/DMSO) solvents resulted in the identification of 17 constituents, principally alkaloids (alstonerine, 34.38%; strictamin, 5.23%; rauvomitin, 4.29%; and brucine, 3.66%) and triterpenoids (γ-sitosterol, 3.85%; lupeol, 3.00%; 24-methylenecycloartanol, 2.81%; campesterol, 2.71%; β-amyrin, 2.30%; and stigmasterol, 2.13%). MeOH/DMSO samples of AM were used in the selected bioassays. The samples exhibited efficient free radical scavenging activity (IC₅₀ = 0.71 mg/mL) and were noncytotoxic to normal HDFn (IC₅₀ > 100 μg/mL) and neoplastic THP-1 cell lines (IC₅₀ = 67.22 μg/mL) while highly degenerative to MCF-7 (IC₅₀ = 6.34 μg/mL), H69PR (IC₅₀ = 7.05 μg/mL), and HT-29 (IC₅₀ = 9.10 μg/mL). Most interestingly, the AM samples inhibited the northern Philippine Cobra's (Naja philippinensis Taylor) venom (IC₅₀ = 297.27 ± 9.33 μg/mL) through a secretory phospholipase A₂ assay.

Isolation of Antimicrobial Compounds From Cnestis ferruginea Vahl ex. DC (Connaraceae) Leaves Through Bioassay-Guided Fractionation

Different parts of Cnestis ferruginea are used in traditional African medicine for treating infectious diseases such as dysentery, bronchitis, eye troubles, conjunctivitis, sinusitis, gonorrhea, and syphilis. Despite its long traditional use in the treatment of infections, this plant is not well studied for its in vitro antimicrobial properties. Therefore, the present study aims to establish the antimicrobial activity profile of extracts from this plant, as well as to isolate and evaluate the antimicrobial activity of the most abundant bioactive compound in C. ferruginea leaves through bioassay-guided purification, using Staphylococcus aureus as a target organism. Although both methanol and water extracts of the plant leaves proved active against S. aureus, a water extract was pursued, and subjected further to liquid-liquid partitioning (ethyl acetate, butanol, and water). The ethyl acetate fraction was found to be the most potent and was subjected to silica gel chromatography. In total, 250 fractions were obtained, and those with similar TLC profiles were clustered into 22 major groups, of which pooled fraction-F6 (83 mg) was the most potent. Additional purification by HPLC resulted in two active peaks, which were identified, using a combination of NMR and mass spectrometry, as hydroquinone and caffeic acid methyl ester. Their antimicrobial activity was confirmed using a microdilution protocol on S. aureus, where hydroquinone had a stronger activity (MIC50 = 63 μg/mL) compared to caffeic acid methyl ester (>200 μg/mL). Traditionally this plant is used as an aqueous preparation to treat many infections, and the present study also demonstrated antimicrobial activity in the aqueous extract, which appears due mainly to two major water-soluble compounds isolated through bioassay-guided purification. This supports the clinical use of the aqueous extract of C. ferruginea leaves as a phytotherapeutic for bacterial infections.

Aqueous extracts of Syzygium brazzavillense can inhibit the infection with coxsackievirus B4 in vitro

Traditional practitioners commonly use plant crude extracts to treat various diseases in patients with symptoms that can be seen during enterovirus infections. In this study, the antienteroviral activity of medicinal plants from the Republic of Congo has been evaluated in vitro. Through an ethnopharmacological approach, seven plants grouped into six families were identified. Aqueous and organic extracts of various organs from these plants were prepared. The organic extracts at subcytotoxic concentrations did not inhibit the cytopathic effect (CPE) induced by coxsackievirus (CV)B1-5, CVA6, poliovirus type 1, and enterovirus 71. The aqueous extract of Syzygium brazzavillense, but not those of other plants, inhibited the CPE induced by CVB3 and CVB4 at 30 µg/mL (CC₅₀ ; 2800 µg/mL, IC₅₀ ; 0.8 µg/mL) and by CVB2 and poliovirus type 1 at higher concentrations. When aqueous extract of this plant was mixed with CVB4, the replication of the virus was inhibited. In conclusion, aqueous extracts of Syzygium brazzavillense can inhibit the infection with CVB4 and other enteroviruses in vitro. The present ethnopharmacological investigation helped to identify a plant with potential properties useful to combat enterovirus infections.

Funiculosone, a substituted dihydroxanthene-1,9-dione with two of its analogues produced by an endolichenic fungus Talaromyces funiculosus and their antimicrobial activity

An undescribed substituted dihydroxanthene-1,9-dione, named funiculosone, was isolated together with its two analogues identified as mangrovamide J and ravenelin, from the culture filtrates of Talaromyces funiculosus (Thom) Samson, Yilmaz, Frisvad & Seifert (Trichocomaceae), an endolichenic fungus isolated from lichen thallus of Diorygma hieroglyphicum (Pers.) Staiger & Kalb (Graphidaceae), in India. Funiculosone was characterized, essentially by spectroscopic methods, as 4,8,9a-trihydroxy-3,4a-dimethyl-4a,9a-dihydro-4H-xanthene-1,9-dione. Its relative stereochemistry was deduced by single crystal X-ray analysis while the absolute configuration was assigned as 4S,4aS,9aS by ECD spectra in comparison to that of the closely related mangrovamide J. This latter, to which, not being an amide, an inappropriate common name was given, was only recently isolated, together with undescribed and known prenylatedindole alkaloids and chromone derivatives from an unidentified Penicillium sp. X-ray structural analysis of the isolated mangrovamide J, for which no biological activity was previously reported, revealed polymorphism and a new crystalline phase is described. All the compounds displayed antibacterial activity with an IC₅₀ range 23-104 μg/mL when assayed against Escherichia coli Escherich and Staphylococcus aureus Ogston. Funiculosone also showed anticandidal activity against Candida albicans Berkhout with an IC₅₀ 35 μg/mL.