Antimicrobial activity of some Indian medicinal plants

A comprehensive review on Saraca asoca (Fabaceae) - Historical perspective, traditional uses, biological activities, and conservation

ETHNOPHARMACOLOGICAL RELEVANCE

Saraca asoca (Roxb.)W.J.de Wilde, (Fabaceae) is a plant of significant medicinal value in traditional Indian medicine, with a long history of use in the treatment of gynaecological disorders and other ailments, and is held in high esteem. This plant has long existed in Indian tradition and is revered as sacred.

AIM OF THE STUDY

This work aimed to explore the taxonomic revision of Saraca asoca from ancient times to the present and to evaluate the ethnobotanical, phytochemical and pharmacological information associated with traditional use and develop a roadmap for conservative strategies of species.

MATERIALS AND METHODS

The study draws on a comprehensive range of herbal, traditional, ethnobotanical, and ethnopharmacological information, including ancient Ayurvedic textbooks and various databases, using a single keyword or a combination of multiple keywords.

RESULTS

This review establishes a roadmap for understanding the traditional history of medicinal plants, particularly Saraca, and highlights the transfer of traditional knowledge from pharmacopoeias, materia medica, and classical textbooks over many centuries. The study also emphasises the importance of conservation strategies to protect Saraca as a valuable resource for healthcare and suggests that more research is needed to systematically evaluate its phytochemical, pharmacological, and clinical properties, as well as to develop safety, pharmacology, and toxicology reports for traditional formulations.

CONCLUSIONS

In light of this study, S. asoca could be considered an important source of potential herbal drugs. The review concludes with a call for further research and conservation efforts to protect Saraca and other traditional medicinal plants for the benefit of current and future generations.

Regulatory Mechanisms for the Conservation of Endangered Plant Species, Chlorophytum tuberosum—Potential Medicinal Plant Species

The present review paper is an attempt to examine and provide an overview of the various conservation strategies and regulatory framework to protect endangered plants, including Chlorophytum tuberosum, popularly known as Safed Musli in the local language. C. tuberosum belongs to the family Liliaceae and is being used in the indigenous systems of medicine as a galactagogue, aphrodisiac, antitumor, immunomodulatory, antidiabetic, analgesic, anti-inflammatory, hypolipidemic, anti-ageing, antimicrobial, etc. This plant has great medicinal and commercial value and is part of the Biological Diversity Act, but due to a lack of effective conservation, it is on the verge of extinction because of natural and manmade reasons, such as loss of habitat, climate change, pollution, excessive harvesting, etc. The most valuable medicinal plants have great importance; hence, many conservation techniques are being employed to protect them. In furtherance to the conservation of such plant species, strategic efforts, in the form of laws and policies, are laid; however, existing legislative mechanisms and policy parameters are not sufficient to overcome the challenges of conservation of such plant species, including Safed Musli, hence, this plant has been considered as a critically endangered plant in India. It is pertinent to note that we do not have specific legislation enacted for the protection of plant species; however, efforts are being made to conserve it under various laws, such as the Forest Conservation Act, Biological Diversity Act 2002, and many other allied legislations. This basic legislation of the Biological Diversity Act also lacks focal attention on the conservation of endangered plant species. Moreover, decentralization of power and actual community participation in conservation practices are also missing. A cumulative effect of both scientific measures and legal mechanisms supported by community participation may produce better results in the conservation of plant species, including Safed Musli. The protection of rich sources and biological diversity is not being taken as seriously as it ought to be, hence, it is necessary to improve awareness and public participation in conservation techniques with effective legislation for the conservation of highly endangered plant species.

Antidiabetic activity of mango peel extract and mangiferin in alloxan-induced diabetic rats

Background

In diabetic animals, there is a significant increase in plasma glucose, serum total cholesterol, triglyceride, and low-density lipoprotein levels, and decreased body weight, liver and muscle glycogen, and high-density lipoprotein. Effective treatment of diabetes mellitus is not yet known, even though the management of diabetes mellitus is considered a global concern. Plants and herbs have played an important role in the healthcare of many societies throughout history. Today’s researchers are investigating the potential for using these nonpharmaceutical approaches to treat and control diabetes, either in conjunction with standard treatments or as an alternative to them. Herbal formulations are favored because to lower cost and fewer side effects compared to other methods for alleviating diabetes and its consequences. In ethnomedicinal practices, different parts of Mangifera indica are used to treatment of diabetes. The present investigation was undertaken to evaluate the antidiabetic activity of an ethanolic extract of Mangifera indica and mangiferin in alloxan-induced diabetic rats. This experiment was conducted in a set of two with four groups of animals namely control (Tc), treatment alloxan (Ta), treatment extract (Tae), and treatment mangiferin (Tam). To develop diabetes, Wistar rats treated with 150 mg/kg b.w. of alloxan monohydrate were injected intraperitoneally. Tae and Tam’s groups received a freshly prepared single dose of extract and mangiferin in distilled water via the oral route. All experimental groups received laboratory pallet feed diet and drinking water ad libitum. Diabetic rats were treated for 21 days with an ethanolic extract of mango peel and pure mangiferin orally daily at rates of 200 mg/kg b.w. and 20 mg/kg b.w.

Results

An alloxan-induced diabetic rat treated with mango peel extract and mangiferin significantly improved the overhead impact due to diabetes. There was a significant (p < 0.05) body weight loss in the alloxan-induced diabetic rats (Ta), whereas animals given mango peel extract and mangiferin showed a significant increase in body weight from 2 weeks onwards in comparison with control. Alloxan-induced rats (Ta) group have higher blood glucose levels and are significantly different (p < 0.01) from the control group. Mango peel extract and mangiferin significantly reduced the levels of fasting glucose after 21 days of treatment in comparison with diabetic animals. Mango peel extract and mangiferin influence the glycogen synthesis pathway in diabetes groups by increasing glycogen levels in muscle and liver. mango peel extract and mangiferin were found to have a nonsignificant impact on plasma cholesterol and HDL levels compared with the control group. Mango peel extract was found to have a significant difference (p < 0.05) in LDL levels compared with the control group. Mangiferin was found to have a significant difference (p < 0.05) in triglyceride and VLDL levels when compared with the control group. Histopathological examination of the pancreas in rats with type I diabetes caused by alloxan found that therapy with an ethanolic extract of mango peel and mangiferin restored beta cell function as well as rejuvenation of Islets of Langerhans.

Conclusions

Mango peel extract and mangiferin have antidiabetic, glycogenesis, and hypolipidemic properties when administered to alloxan-induced diabetic rats.

Graphical abstract

Quantification of Phenolic and Flavonoid Content, Antioxidant Activity, and Proximate Composition of Some Legume Seeds Grown in Nepal

This study was carried out to evaluate some legume seeds growing in Nepal for their proximate composition, quantification of total phenolic (TPC) and flavonoid (TFC) contents, and in vitro, antioxidant and antidiabetic activities. These included legume grains such as chickpeas (Cicer arietinum), pea (Pisum sativum), mung bean (Vigna mungo), lima bean (Phaseolus lunatus), broad bean (Vicia faba), lentil (Lens culinaris), soybean (Glycine max), and common bean (Phaseolus vulgaris). The legume seeds were ground to make the flour which was extracted with methanol. The phenolic and flavonoid content was estimated by Folin-Ciocalteu’s phenol and aluminum chloride colorimetric methods. The in vitro antioxidant and antidiabetic activity was evaluated by using DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging and α-amylase enzyme inhibition assay. The different legumes showed considerable variations in their phenolic contents ( $30.64\pm 1.50$  mg·GAE/g to $46.65\pm 1.25$  mg·GAE/g legume seeds). Similarly, the total flavonoid contents showed $135.5\pm 10.88$  mg·QE/g to $191.7\pm 8.73$  mg·QE/g legume seeds. The in vitro antioxidant activity was evaluated in IC50 which ranged from $31.60\pm 0.06$  μg/mL to $69.74\pm 0.89$  μg/mL. The α-amylase inhibition was evaluated in IC50 which ranged from 217.38 μg/mL to 425.75 μg/mL as compared to the standard acarbose of 52.76 μg/mL. This study suggested that legumes are good sources of proteins, carbohydrates, and fats mainly for vegetarian people. The selection of the right legume species could be a good source of natural antioxidants and antidiabetics for nutraceutical uses and the beneficial effects of legumes from human health perspectives. Legume seeds growing in Nepal could be used as a sustainable and cheap meat alternative and are considered the most important food source.

GC-MS Analysis, Heavy Metals, Biological, and Toxicological Evaluation of Reseda muricata and Marrubium vulgare Methanol Extracts

The usage of herbal remedy is growing vividly all around the world. Though, ecological contamination particularly with heavy metals carriages thoughtful problem on quality of medicinal plants and their foodstuffs. In the world, 80% of the population depend on traditional medicine, while information on the levels of heavy metal such as Zn, Mn, Cu, Cr, Pb, As, Cd, and Cr in plants utilized for making of herbal remedies is unavailable. Therefore, the purpose of this study was to assess phytochemicals, biological activities, and heavy metal analysis of Reseda muricata and Marrubium vulgare grown in different parts of Saudi Arabia. Qualitative phytochemical analysis of R. muricata and M. vulgare confirmed the presence of alkaloids, flavonoids, tannins, phenol, and saponins. Methanol extracts of both Reseda muricata and Marrubium vulgare were characterized with the help of GC-MS. Antioxidants, antimicrobial, and brine sharp lethal toxicity of the both species were also evaluated.

Ultrasound-Assisted and Microwave-Assisted Extraction, GC-MS Characterization and Antimicrobial Potential of Freeze-dried L. Camara Flower

Lantana camara is known to have anti-bacterial properties which can be exploited to develop a natural food preservative. There is huge demand for natural preservatives in food industry due to the increased health risks associated with synthetic preservatives, development of effecient extraction methods are essential to retain heat sensitive bioactive compounds. This aim of this study was to compare the performance of microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and conventional solvent extraction (CSE) methods for extraction of freeze-dried lantana flower. The phytochemicals in freeze-dried flowers were characterized by GC-MS analysis and antibacterial properties were tested at different concentrations (50, 100, and 150 µl) against E.coli, Salmonella, and S. aureus. It was evident that the UAE offered the highest yield (64%), followed by MAE (53%) and CSE (49%) with distilled water as solvent. The freeze-dried extract possessed a high amount of tannins (417 µg/g), followed by flavonoids such as catechol (88 µg/g) and quercetin (9.2 µg/g). The antibacterial potential results revealed that only distilled water-based extraction techniques offered positive inhibition zones of 2.0-2.67 mm (MAE), 1.67-2.67 mm (UAE), and 1.67-2.17 mm (CSE) against all three organisms, while the chloroform based extracts had no inhibition effect. The microwave-assisted extract at 150 µl concentration offered a significant inhibitory effect against all three pathogens. The GC-MS profiling of bioactive compounds in flower extract revealed the presence of hexadecanoic acid as the major phytochemical compound in all three extraction techniques. The study revealed that the chloroform extract failed to exhibit an antibacterial effect due to the absence of alkaloids, saponins, and anthraquinones as a result of its neutralizing effect.

A new megastigmane, known porphyrinic and galloylated bioactive derivatives from the leaves of Gymnosporia senegalensis

Investigation of the non-polar (rich in chlorophyll) and polar fractions of the ethyl acetate extract of Gymnosporia senegalensis (Lam.) Loes. leaves led to the isolation of nine compounds, including one new megastigmane derivative, (3 R*,5 S*,6 R*,7 E,9ξ)-7-megastigmene-3,6,9-triol-3- O-β-D-(6′- O-galloyl)glucopyranoside (1), four known galloylated derivatives (2, 3, 8, 9), three known chlorophyll derivatives (4–6), and one known fatty acid (7). The structures of the isolates were determined by means of spectroscopic and spectrometric data, as well as by comparison with literature values. The extracts and isolated compounds were tested for their antibacterial, antifungal, and antioxidant activities. The isolates showed weak to high antimicrobial activities with phaeophytin A (4) being the most active one whereas phaeophorbide-a (5) and Chlorine e6 trimethyl ester (6) exhibited the highest antioxidant activities.

Evaluation of antioxidant enzyme content, phenolic content, and antibacterial activity of Commiphora gileadensis grown in Saudi Arabia

Commiphora gileadensis is commonly used in Saudi Arabia for oral hygiene. A lack of data about its biological activity encouraged us to evaluate the antioxidant and antibacterial activities of its leaf and stem extracts. Ethanol, methanol, acetone and deionized water were tested as extraction solvents. 80% methanol gave the highest extracted concentrations of phenolic and flavonoid substances. The leaf and stem extracts were respectively evaluated for their radical scavenging activity with DPPH (EC50 = 3.39, and 1.06), ABTS (EC50 = 0.690, and 0.55), and peroxide scavenging activity (EC50 = 2.43, and 1.28). GC-MS identified a wide range of compounds that may be responsible for these activities of the results observed. The highest levels of chlorophyll, carotenoids, and lycopene were found in the leaf extract while level of proanthocyanidins was found in the stem peels extract. The peroxidase and catalase activities of stem peel extract were higher than those of the leaf extract. The findings showed that the leaf and stem peel extracts of C. gileadensis exhibited significant antibacterial activity against the test organisms. The minimum inhibitory concentrations for the plant extracts were compared with the standard reference drug Augmentin but the time–kill curves for the C. gileadensis extracts showed that they were less effective than Augmentin. Moreover, the stem peel extract exhibited stronger antibacterial activity than the leaf extract. In conclusion, C. gileadensis can be an important source of natural antioxidants, used as a healthy chewing stick for teeth brushing and oral hygiene purposes.

Screening of the Dichloromethane: Methanolic Extract of Centella asiatica for Antibacterial Activities against Salmonella typhi, Escherichia coli, Shigella sonnei, Bacillus subtilis, and Staphylococcus aureus

Bacterial infections are responsible for a large number of deaths every year worldwide. On average, 80% of the African population cannot afford conventional drugs. Moreover, many synthetic antibiotics are associated with side effects and progressive increase in antimicrobial resistance. Currently, there is growing interest in discovering new antibacterial agents from ethnomedicinal plants. About 60% of the population living in developing countries depends on herbal drugs for healthcare needs. This study involved the screening of Centella asiatica commonly used by herbal medicine practitioners in Kisii County to treat symptoms related to bacterial infections. Standard bioassay methods were applied throughout the study. They included preliminary screening of dichloromethane: methanolic extract of Centella asiatica against human pathogenic bacteria including Salmonella typhi ATCC 19430, Escherichia coli ATCC 25922, Shigella sonnei ATCC 25931, Bacillus subtilis ATCC 21332, and Staphylococcus aureus ATCC 25923 using agar disc diffusion, broth microdilution method, and time-kill kinetics with tetracycline as a positive control. Phytochemical screening was carried out to determine the different classes of compounds in the crude extracts. Data were analyzed using one way ANOVA and means separated by Tukey's test. Dichloromethane: methanolic extract of Centella asiatica was screened against the selected bacterial strains. Time-kill kinetic studies of the extracts showed dose- and time-dependent kinetics of antibacterial properties. Phytochemical screening of the DCM-MeOH extract revealed the presence of alkaloids, flavonoids, phenolics, terpenoids, cardiac glycosides, saponins, steroids, and tannins. The present study indicates that the tested plant can be an important source of antibacterial agents and recommends that the active phytoconstituents be isolated, identified, and screened individually for activities and also subjected further for in vivo and toxicological studies.

Insight into the screening of potential beta-lactamase inhibitors as anti-bacterial chemical agents through pharmacoinformatics study

Drug resistance is an unsolved and major concern in the bacterial infection. Continuous development of drug-resistance to the antibiotics exponentially rises the danger of bacterial infections. Chemical components from the plants are becoming a major resource of potentially effective therapeutic chemical agents for the wide range of diseases including bacterial infections. In the current study, pharmacoinformatics methodologies were implemented on more than two hundred known phytochemicals to find promising beta-lactamase inhibitors for therapeutically effective anti-bacterial agents. Initially, the molecular docking-based score was used to reduce the chemical space of the selected dataset. Fourteen molecules were found to have more affinity towards the beta-lactamase in compared to the well-known anti-bacterial agent, Avibactam. Binding interactions analysis revealed the strong binding interactions between phytochemicals and catalytic amino residues. For further analysis, molecular dynamics (MD) simulations, density functional theory (DFT) and in silico pharmacokinetics studies were performed. Parameters from MD simulations studies suggested that selected molecules are strong enough to retain in the active site in different orientations of the beta-lactamase. The orbital energies obtained from the DFT study was undoubtedly explained the potentiality of the selected compounds for being effective beta-lactamase inhibitors. The drug-likeness and acceptable pharmacokinetics parameters were observed using in silico ADME analysis. Therefore, observations from the multiple pharmacoinformatics approach explained without any doubt that selected molecules are potential enough being promising anti-bacterial compounds. [Formula: see text] Communicated by Ramaswamy H. Sarma.

Review on antibacterial activity of Himalayan medicinal plants traditionally used to treat pneumonia and tuberculosis

Objectives

The main objective of this review was to collect scattered literature on ethnomedicinal plants used to treat pneumonia and tuberculosis in the Himalayan region and their in-vitro validation against bacterial pathogens.

Key findings

Current review contains information on ethnomedicines of total 137 plants from Himalaya region. Out of these, 59 plants have been studied in vitro against bacteria while seven plants extracts have been checked for their toxicological effects. The most commonly used plant families for pneumonia and tuberculosis therapy in the study region were Asteraceae, Bignoniaceae and Fabaceae (seven plants in each); of these, Curcuma longa L., Punica granatum L. and Justicia adhatoda L. carried the most inhibiting potential against Staphylococcus aureus and Streptococcus pneumoniae while that of Acalypha indica L. against Mycobacterium tuberculosis. Different compounds such as ascorbic acid, curcumin, vasicine, piperine, quercetin, myricetin and gallic acid being reportedly isolated from these plants possess antibacterial potential.

Summary

Himalayan region has variety of ethnomedicinal plants used against pneumonia and tuberculosis; however, studies on in-vivo activity, toxicology and mechanism of action are very limited. Hence, detailed investigation on these aspects needs to be carried out for the development of novel antibacterial drugs from the studied plant species.

Jatropha gossypiifolia L. and its biologically active metabolites: A mini review

ETHNOPHARMACOLOGICAL RELEVANCE

Jatropha gossypiifolia L. (Euphorbiaceae) is popularly known as bellyache bush or black physic nut and is widely used in local / traditional medicine due to the various biological activities attributed to its different parts, including its leaves, roots, and latex.

AIM OF THE STUDY

In this review, we aim to update and discuss the chemistry, specific pharmacology, and toxicological activities of Jatropha gossypiifolia and its bioactive metabolites.

MATERIALS AND METHODS

The Web of Science, PubMed, Google Scholar, SciFinder, Cochrane Library, Scopus, and Science Direct databases were searched with the name "Jatropha gossypiifolia" and the term "bioactive metabolites". All studies on the chemistry, pharmacology, and toxicology of the plant up to December 2018 were included in this review.

RESULTS

Jatropha gossypiifolia leaves are considered to have anti-inflammatory, antimicrobial and insecticidal properties. The root and stem have anti-inflammatory and antimicrobial properties. The seeds and fruits can be used against influenza and as a sedative, analgesic or anti-diarrheal agents. The latex is bactericidal and molluscicidal. Topical application of latex is used to treat wounds and bites of venomous animals. The diluted form is usually used for the treatment of diarrhoea by indigenous peoples.

CONCLUSIONS

The main pharmacological activities of Jatropha gossypiifolia include anti-inflammatory, antineoplastic, antimicrobial, antioxidant, and anticholinesterase, and antihypertensive activities. Species of Jatropha are notably known for their toxic potential, and their toxicity is primarily related to the latex and seed contents. However, the potential mechanisms of these pharmacological activities have not been fully explored. We hope this review will help to further inform the potential utilization of Jatropha gossypiifolia in complementary and alternative medicine.

Chemical Constituents with Leishmanicidal Activity from a Pink-Yellow Cultivar of Lantana camara var. aculeata (L.) Collected in Central Mexico

Lantana camara (L.) is employed by several ethnical groups to treat numerous diseases. Although there are no ethnomedical reports on its use against leishmaniasis, organic extracts prepared from L. camara were shown to display leishmanicidal activity. In the present study, we carried out a bioassay-guided fractionation of the dichloromethane extract from Mexican L. camara in order to identify the compounds responsible for the leishmanicidal activity. Eighteen chromatographic fractions (FI⁻FXVIII) were evaluated in vitro against Leishmania mexicana and L. amazonensis. FII, FX, FXI, FXV, and FXVI showed significant activity against both Leishmania strains, the most potent of which was FXV. Eicosane (1), squalene (2), β-ionone (3), caryophyllene oxide (4), β-caryophyllene (5), hexanoic acid (6), tiglic acid (7), a mixture of lantanilic (8) and camaric (9) acids, and lantadene B (10) were identified and obtained from the active fractions and evaluated for their leishmanicidal activity. The mixture of lantanilic (8) and camaric (9) acids (79%/21%) was the most potent one (half maximal inhibitory concentration (IC₅₀) = 12.02 ± 0.36 μM). This study indicates that this cultivar of L. camara has high potential for the development of phytomedicines or as a source of natural products, which might represent lead compounds for the design of new drugs against leishmaniasis.

Isolation of anti-Saprolegnia lignans from Magnolia officinalis and SAR evaluation of honokiol/magnolol analogs

To control the fish fungal pathogen Saprolegnia, the effects of the petroleum ether extracts of Magnolia officinalis were evaluated by a rapeseed (Brassicanapus) microplate method in vitro. By loading on an open silica gel column and eluting with petroleum ether-ethyl acetate-methanol, honokiol (C₁₈H₁₈O₂) and magnolol (C₁₈H₁₈O₂) were isolated from Magnolia officinalis. Saprolegnia parasitica growth was inhibited significantly when honokiol concentration was >8.0 mg/L, and magnolol concentration was >9.0 mg/L, with EC₅₀ values of 4.38 and 4.92 mg/L, respectively. Six honokiol and magnolol derivatives were designed, synthesized and evaluated for their anti-Saprolegnia activity. According to the results, double bond and hydroxyl played an important role in inhibiting Saprolegnia. Mechanistically, through the scanning electron microscope observation, honokiol and magnolol could cause the Saprolegnia parasitica mycelium tegumental damage including intensive wrinkles and nodular structures. Moreover, compared to traditional drugs kresoxim-methyl (LC₅₀ = 0.66 mg/L) and azoxystrobin (LC₅₀ = 2.71 mg/L), honokiol and magnolol showed a lower detrimental effect on zebrafish, with the LC₅₀ values of 6.00 and 7.28 mg/L at 48 h, respectively. Overall, honokiol and magnolol were promising lead compounds for the development of commercial drugs anti-Saprolegnia.

Protective efficacy of Chlorophytum borivilianum root extract against murine visceral leishmaniasis by immunomodulating the host responses

BACKGROUND

The available drugs for treating visceral leishmaniasis are limited. Moreover, the disease is associated with suppression of immune function. Therefore, therapies with effective immunomodulatory agents are needed which can decrease parasitic burden and enhance adaptive immunity.

OBJECTIVES

The present study was planned to evaluate the antileishmanial efficacy of crude ethanolic extract of roots of Chlorophytum borivilianum (CBREE) against murine visceral leishmaniasis through immunomodulation.

MATERIALS AND METHODS

The in vitro studies were carried out to check leishmanicidal activity against promastigote form and cytotoxicity against HeLa cells. The parasite load in liver smears, immunological and biochemical changes induced by 500 and 1000 mg/kg b.wt. of CBREE were assessed on 1, 7, 14 and 21 post treatment days in infected and treated BALB/c mice.

RESULTS

CBREE showed inhibitory effect on growth of promastigotes with IC50 of 28.25 μg/mL and negligible cytotoxicity. The extract was toxicologically safe in BALB/c mice when administered orally with 5 g/kg b.wt. of extract. A significant reduction in parasite load was observed along with active immunomodulation through enhanced Th1 type of immune responses and suppressed Th2 type of immune responses.

CONCLUSION

The treatment with both doses showed no toxic effect as evidenced by normal liver and kidney function tests and normal histological observations of liver and kidney. Therefore, it should be further explored for its active components in pursuit of the new effective antileishmanial agents in the plant kingdom.

Effect of salicylic acid and methyl jasmonate in the production of phenolic compounds in plant cell suspension cultures of Thevetia peruviana

The objective was to enhance the production of the phenolic compounds in plant cell suspension cultures of T. peruviana at shake flask scale. The effects of salicylic acid (SA), methyl-jasmonate (MeJA) and the combination of both (SA/MeJA) were studied. Elicitor concentration, elicitation time and harvest time of cells were optimized. Phenolic compound content (PCC), flavonoid content (FC) and antioxidant activity (AA) were determined by the folin-ciocalteu method, flavonoid-aluminum complexation method and the ABTS assay, respectively. Differences between intracellular metabolite profiles due to the mentioned treatments were analyzed by Thin-layer chromatography and High-performance liquid chromatography. Highest PCC, FC and AA were obtained under the following treatments: 3 μM MeJA > 3 μM MeJA/300 μM SA > 300 μM SA > control, when elicited on the 4^th day and harvested 96-h post-elicitation. It was demonstrated that exposure to 3 μM MeJA increase 1.49-fold of PCC, 1.66-fold of AA and 2.55-fold of FC compared to the control culture.

Antimicrobial metabolites from Saraca asoca impairs the membrane transport system and quorum-sensing system in Pseudomonas aeruginosa

This study was conducted to explore the antimicrobial mechanism of metabolites from Saraca asoca (SA1) using differential proteomics and metabolic profile of Pseudomonas aeruginosa after treatment with effective sub-MIC dose of 312 µg/mL. SA1 fraction was found to contain antibacterial metabolites catechol, protocatechuic acid, and epigallocatechin gallate. Proteome analysis revealed 33 differentially expressed proteins after SA1 treatment. Protein network analysis showed that SA1 treatment upregulated the DNA topological and metabolic processes. Furthermore, it revealed that T2SS, cellular component biogenesis, and response to chemical stimuli were inhibited by SA1 treatment, supported by down-regulated Na⁺/H⁺ antiporter, SdeX, ompK, and trbD proteins. Statistical analysis of mass data revealed the altered level of 20 metabolites includes HSLs, PQS, rhamnolipid, and pyocyanin. Proteome and metabolome results showed that treatment impaired cell membrane functions and quorum-sensing system. It was further confirmed by increased MDA (3.95 fold), and rhamnolipids (4.3 fold) production and, therefore, oxidative stress (36.9%) after SA1 treatment.

Phytochemicals: Extraction, Isolation, and Identification of Bioactive Compounds from Plant Extracts

There are concerns about using synthetic phenolic antioxidants such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) as food additives because of the reported negative effects on human health. Thus, a replacement of these synthetics by antioxidant extractions from various foods has been proposed. More than 8000 different phenolic compounds have been characterized; fruits and vegetables are the prime sources of natural antioxidants. In order to extract, measure, and identify bioactive compounds from a wide variety of fruits and vegetables, researchers use multiple techniques and methods. This review includes a brief description of a wide range of different assays. The antioxidant, antimicrobial, and anticancer properties of phenolic natural products from fruits and vegetables are also discussed.

Steroidal saponins from Chlorophytum deistelianum

Phytochemical investigation of the aerial parts of Chlorophytum deistelianum led to the isolation of four previously undescribed steroidal saponins called chlorodeistelianosides A-D with five known ones. Their structures were established mainly by extensive 1D and 2D NMR spectroscopic techniques and mass spectrometry as (25R)-3β-[(β-D-glucopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→4)]-β-D-xylopyranosyl-(1→3)-[β-D-glucopyranosyl-(1→2)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranosyl)oxy]-5α-spirostan-12-one, (24S,25S)-24-[(β-D-glucopyranosyl)oxy]-3β-[(β-d-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranosyl)oxy]-5α-spirostan-12-one, (25R)-26-[(β-D-glucopyranosyl)oxy]-2α-hydroxy-22α-methoxy-5α-furostan-3β-yl β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside, and (25R)-26-[(β-D-glucopyranosyl)oxy]-3β-[(β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranosyl)oxy]-5α-furost-20(22)-en-12-one. Cytotoxicity of most compounds was evaluated against one human cancer cell line (SW480) and one rat cardiomyoblast cell line (H9c2). Among them, three known spirostane-type glycosides exhibited cytotoxicity on both cell lines with IC50 ranging from 8 to 10 μM.

Chinese herbal medicines as a source of molecules with anti-enterovirus 71 activity

Enterovirus 71 (EV71) is one of the causative agents of hand, foot, and mouth disease (HFMD), which sometimes leads to severe neurological disease and death in the Asia-Pacific region. In Chinese medicine, HFMD is caused mainly by an accumulation of damp-heat and toxicity in the body. No effective drugs are currently available for the treatment and prevention of EV71 infection. This review summarizes the potential Chinese herbal extracts and isolated compounds with antiviral activity against EV71 and their clinical applications, especially those categorized as heat-clearing and detoxifying.

Herbal extracts in oral health care - A review of the current scenario and its future needs

BACKGROUND

Oral diseases are among the major public health problems and the commonest of chronic diseases that affect mankind. The application of natural products for the control of oral diseases is considered as an interesting alternative to synthetic antimicrobials due to their lower negative impact, and for the effort to overcome primary or secondary resistance to the drug during therapy.

OBJECTIVE

To review the current evidence on the antimicrobial efficacy of 10 plant extracts on dental caries and plaque microorganisms.

MATERIALS AND METHODS

A comprehensive literature search was made by one of the authors for 2 months in PubMed, PubMed Central, MEDLINE, LILACS/BBO, Cochrane database of systematic reviews, SCIENCE DIRECT, and Google scholar databases. The results from the relevant published literatures are discussed.

SUMMARY AND CONCLUSION

The extracts of Azadirachta Indica, Ocimum sanctum, Murraya koenigii L., Acacia nilotica, Eucalyptus camaldulensis, Hibiscus sabdariffa, Mangifera indica, Psidium guajava, Rosa indica, and Aloe barbadensis Miller have all been found to inhibit certain dental caries and periodontal pathogens. The current evidence is on individual plant extracts against bacteria involved in either caries or periodontitis. "Herbal shotgun" or "synergistic multitarget effects" are the terms used for the strategy of combining different extracts. The research assessing the antimicrobial efficacy of a combination of these plant extracts against dental caries and periodontal pathogens is the need of the hour, and such research will aid in the development of a novel, innovative method that can simultaneously inhibit two of the most common dental diseases of mankind, besides slowing the development of drug resistance.

Antimicrobial efficacy of Acacia nilotica, Murraya koenigii L. Sprengel, Eucalyptus hybrid, and Psidium guajava on primary plaque colonizers: An in vitro comparison between hot and cold extraction process

Background:

The potential drawbacks of the existing antiplaque agents call for innovative strategies that are safe, effective, and easily available.

Objective:

The objective was to assess and compare antimicrobial efficacy of four plant extracts derived using hot and cold extraction methods against Streptococcus mutans, Streptococcus sanguis, and Streptococcus salivarius.

Materials and Methods:

The leaves of Acacia nilotica, P. guajava, Eucalyptus hybrid, and Murraya konigii L. Sprengel were collected from the surrounding areas, identified and authenticated by a taxonomist. The leaves were washed, shade-dried, and hand crushed to obtain coarse powder. This was subsequently ground into a fine powder and extracted using ethanol by cold infusion and hot extraction process. The antimicrobial efficacy testing was done on American Type Culture Collection strains of S. mutans, S. sanguis, and S. salivarius using agar well diffusion method. 0.2% chlorhexidine and dimethyl sulfoxide were used as positive and negative controls. The mean inhibition zone using 10% concentration of these extracts was compared using independent sample t-test and one-way analysis of variance.

Results:

All the four plant extracts inhibited the growth of S. mutans, S. sanguis, and S. salivarius irrespective of the method of extraction. The extracts of A. nilotica, P. guajava, and E. hybrid derived from both the methods of extraction exhibited a significantly higher inhibition zone against S. mutans in comparison with Murraya koenigii L. Sprengel and chlorhexidine. The cold extracts of A. nilotica and E. hybrid exhibited higher zone of inhibition against S. sanguis while the hot extracts of M. koenigii L. Sprengel exhibited a higher zone of inhibition against S. mutans.

Conclusion:

All the four plant extracts derived using either hot or cold extraction were effective against these bacteria and have the potential to be used as antiplaque agents.

Antimicrobial efficacy of the combinations of Acacia nilotica, Murraya koenigii L. sprengel, Eucalyptus hybrid and Psidium guajava on primary plaque colonizers

Background:

There is an urgent need for innovative strategies to combat the two most common dental diseases of mankind namely dental caries and periodontitis.

Objective:

The aim was to assess the antimicrobial efficacy of the double combinations of Acacia nilotica (AN), Murraya koenigii L. Sprengel (MKL), Eucalyptus hybrid and Psidium guajava on primary plaque colonizers.

Materials and Methods:

The plant extracts of AN, MKL. Sprengel, Eucalyptus hybrid and P. guajava were prepared using Soxhlet apparatus. The stock solutions of individual plant extracts (100 mg/ml) were prepared. Equal quantities of stock solutions were mixed to obtain six double combinations of herbal extracts. The antimicrobial efficacy testing was done against three primary plaque colonizers using agar well-diffusion method. 0.2% chlorhexidine and dimethyl sulfoxide were used as positive and as negative controls. The mean inhibition zone between the categories was compared using one-way Analysis of Variance and Tukey's post hoc test.

Results:

The combination of AN and P. guajava produced the highest mean diameter of inhibition zone (21.08 mm ± 2.11) against Streptococcus mutans. The chlorhexidine produced the least inhibition zone against S. mutans (14.50 ± 2.07). The combination of AN and P. guajava produced the maximum antimicrobial efficacy against Streptococcus sanguis (19.67 ± 1.03) and Streptococcus salivarius (20.33 ± 1.86).

Conclusion:

All the combinations of plant extracts have the potential to be used as antiplaque and anticaries agents. The combinations of herbal extracts offer enhanced antimicrobial efficacy due to the synergistic effects besides slowing the development of resistance.

Jatropha gossypiifolia L. (Euphorbiaceae): A Review of Traditional Uses, Phytochemistry, Pharmacology, and Toxicology of This Medicinal Plant

Jatropha gossypiifolia L. (Euphorbiaceae), widely known as “bellyache bush,” is a medicinal plant largely used throughout Africa and America. Several human and veterinary uses in traditional medicine are described for different parts and preparations based on this plant. However, critical reviews discussing emphatically its medicinal value are missing. This review aims to provide an up-to-date overview of the traditional uses, as well as the phytochemistry, pharmacology, and toxicity data of J. gossypiifolia species, in view of discussing its medicinal value and potential application in complementary and alternative medicine. Pharmacological studies have demonstrated significant action of different extracts and/or isolated compounds as antimicrobial, anti-inflammatory, antidiarrheal, antihypertensive, and anticancer agents, among others, supporting some of its popular uses. No clinical trial has been detected to date. Further studies are necessary to assay important folk uses, as well as to find new bioactive molecules with pharmacological relevance based on the popular claims. Toxicological studies associated with phytochemical analysis are important to understand the eventual toxic effects that could reduce its medicinal value. The present review provides insights for future research aiming for both ethnopharmacological validation of its popular use and its exploration as a new source of herbal drugs and/or bioactive natural products.

Studies on Antimicrobial and Immunomodulatory Effects of Hot Aqueous Extract of Acacia nilotica L. Leaves against Common Veterinary Pathogens

Acacia nilotica is a plant species that is almost ubiquitously found in different parts of the world. Various preparations of it have been advocated in folk medicine for the treatment of tuberculosis, leprosy, smallpox, dysentery, cough, ophthalmia, toothache, skin cancer as astringent, antispasmodic, and aphrodisiac since immemorial times. The present study investigates the antibacterial, antifungal, antiviral, and immunomodulatory potential of hot aqueous extract (HAE) of Acacia nilotica leaves. On dry matter basis, the filtered HAE had a good extraction ratio (33.46%) and was found to have carbohydrates, glycosides, phytosterols, phenolic compounds, saponins, and flavonoids as major constituents. HAE produced dose dependent zone of inhibition against Klebsiella pneumoniae, Pseudomonas aeruginosa, E. coli, Bacillus cereus, Staphylococcus aureus, and Streptococcus uberis and fungal pathogens Aspergillus niger and Aspergillus fumigates; however, no antiviral activity was recorded against IBR virus. HAE of A. nilotica revealed both proliferative and inhibitory effects on the rat splenocytes and IL-10 release depending on the dose. Detailed studies involving wide spectrum of bacterial, fungal, and viral species are required to prove or know the exact status of each constituents of the plant extract.

Anticariogenic activity and phytochemical studies of crude extract from some Indian plant leaves

Aim:

The aim was to screen the selected Indian plants for their antibacterial efficacy against four cariogenic bacteria Lactobacillus acidophilus (LA)(Microbial Type Culture Collection [MTCC]-*447), Lactobacillus casei (LC) (MTCC-1423), Streptococcus mutans (SMU) (MTCC-890) and Staphylococcus aureus (MTCC-96). To identify and characterize active principle present in these plants for the treatment of dental caries.

Materials and Methods:

The dried plant leaves materials are extracted by cold extraction using hexane, ethyl acetate, methanol, and distilled water. The solvents were evaporated, and the dried masses were suspended in dimethyl sulfoxide and used for anticariogenic activity by agar well diffusion method. Minimum inhibitory concentration (MIC) was evaluated by two-fold serial broth dilution method. Preliminary phytochemical analysis of effective extract was carried out by thin-layer chromatography (TLC) and bioautography.

Results:

Ethyl acetate and hexane extract of Eucalyptus globules was found most effective against L. acidophilus with MIC value 31 μg/ml and 62 μg/ml, respectively. Ethyl acetate extracts of Acacia nilotica and methanolic extract of E. globules also exhibited antibacterial activity against SMU and L. casei with MIC value of 50 μg/ml. Qualitative analysis of E. globules revealed the presence of alkaloids, terpenoids, phenolic compounds, and cardiac glycosides. The active principle responsible for the anticariogenic activity from E. globules were separated by TLC and subjected to bioautography using SMU, LA and LC.

Conclusion:

Anticariogenic activity and preliminary phytochemical analysis revealed that E. globule have potential to treat dental caries.

Safed musli (Chlorophytum borivilianum): a review of its botany, ethnopharmacology and phytochemistry

ETHNOPHARMACOLOGICAL RELEVANCE

Safed musli (Chlorophytum borivilianum) is an eminent medicinal plant of India and considered as a 'white gold' or 'divya aushad' in Indian systems of medicine. In Ayurveda, Chlorophytum borivilianum belongs to the group of "Vajikaran Rasayana" corroborated to its rejuvenating, aphrodisiac, natural sex tonic properties and effective in alleviating sexual disorders. It is largely used as ethnic medicine by local healers of indigenous communities of India.

MATERIALS AND METHODS

A thorough bibliographic investigation was carried out by analyzing worldwide accepted scientific data base (Pub Med, SciFinder, Scopus and Web of Science), thesis, recognized books, non impact and non indexed journals.

RESULTS

Traditionally, Chlorophytum borivilianum is well known for treating male impotency in India. The multi therapeutic and nutritional importance of Chlorophytum borivilianum is attributed to the rich source of phytochemicals particularly saponins. Recently, Chlorophytum borivilianum has gained a well established domestic (Indian) and international market for being the herbal alternative of "Viagra" without any side effects. Under the trade name 'Nai Chetna', the state government of Gujarat, India, has launched a novel potency drug from Chlorophytum borivilianum. Modern pharmacological studies of Chlorophytum borivilianum have demonstrated a wide range of pharmacological activities, most importantly aphrodisiac, immunomodulatory and anticancer activities.

CONCLUSION

The increased commercial exploitation of Chlorophytum borivilianum and low productivity of this endangered plant has raised the concern over its conservation. It has been envisaged that efforts should be made to standardize, encourage and popularize the cultivation of Chlorophytum borivilianum as a commercial crop. The analysis of previous pharmacological investigations suggested lack of substantial scientific evidences in various studies and do not stand the test of critical assessment. Due to high economic value, Chlorophytum borivilianum has also encountered a problem of adulteration with closely resembling medicinally inferior species. The studies available on toxicity, safety and quality of Chlorophytum borivilianum are inadequate for providing information on commercial utilization. Thus, the present review summarizes comprehensive information on Chlorophytum borivilianum and possible scope for future research to fill the existing lacunae on its different aspects of the study.

β-sitosterol in different parts of Saraca asoca and herbal drug ashokarista: Quali-quantitative analysis by liquid chromatography-mass spectrometry

β-sitosterol is an important component in food and herbal products and beneficial in hyperlipidemia. Its higher concentrations in serum may lead to coronary artery disease in case of sitosterolemia. Therefore, it is essential to determine the quantity of β-sitosterol in food and herbal drugs. Saraca asoca and its preparations have been widely used by traditional healers are also a source of β-sitosterol. In the present study, quantitative estimation of β-sitosterol present in hot and cold water extracts of bark, regenerated bark, leaves and flowers of the S. asoca and Ashokarista drugs were carried out first time using high performance liquid chromatography coupled (HPLC) with quadrupole time-of-flight mass spectrometry. Different concentrations of β-sitosterol and crude extracts were estimated by HPLC and targeted mass spectrometry. Standard curve for β-sitosterol was prepared from the intensities of transitions (397.50 → 147.0987 m/z) having regression coefficient (r (2)) 0.9952. Out of eight extracts and two drugs used in the study bark water, leaves water and leaves hot water extracts were found to have a considerable quantity of β-sitosterol, i.e. 170, 123.5 and 19.3 ng/mL, respectively. The results showed significant differences in the distribution of β-sitosterol among different organs of S. asoca and drugs prepared from its bark. HPLC/electrospray ionizationmass spectroscopy method is accurate, reproducible and requires less specimen, sample preparation and analysis time over HPLC assay. This type of approaches could be helpful for the quality control of herbal medicines and provides necessary information for the rational utilization of plant resources.

Cytotoxic activity screening of Bangladeshi medicinal plant extracts

The cytotoxic activity of 23 crude methanol extracts from 19 Bangladeshi medicinal plants was investigated against healthy mouse fibroblasts (NIH3T3), healthy monkey kidney (VERO) and four human cancer cell lines (gastric, AGS; colon, HT-29; and breast, MCF-7 and MDA-MB-231) using MTT assay. High cytotoxicity across all cell lines tested was exhibited by Aegiceras corniculatum (fruit) and Hymenodictyon excelsum (bark) extracts (IC50 values ranging from 0.0005 to 0.9980 and 0.08 to 0.44 mg/mL, respectively). Fourteen extracts from 11 plant species, namely Clitoria ternatea (flower and leaf), Dillenia indica (leaf), Diospyros peregrina (leaf), Dipterocarpus turbinatus (bark and leaf), Ecbolium viride (leaf), Glinus oppositifolius (whole plant), Gnaphalium luteoalbum (leaf), Jasminum sambac (leaf), Lannea coromandelica (bark and leaf), Mussaenda glabrata (leaf) and Saraca asoca (leaf), were also significantly cytotoxic (IC50 < 1.0 mg/mL) against at least one of the cancer cell lines tested. More selectively, Avicennia alba (leaf), C. ternatea (flower and leaf), Caesalpinia pulcherrima (leaf), E. viride (leaf) and G. oppositifolius (whole plant) showed cytotoxicity only against both of the breast cancer cell lines (MCF-7 and MDA-MB-231). In contrast, C. ternatea (flower and leaf) exhibited high cytotoxic activity against MDA-MB-231 (IC50 values of 0.11 and 0.49 mg/mL, respectively), whereas E. viride and G. oppositifolius whole plant extracts exhibited high activity against MCF-7 cells (IC50 values of 0.06 and 0.15 mg/mL, respectively). The cytotoxic activity test results for 9 of the plant species correlate with their traditional use as anticancer agents, thus making them interesting sources for further drug development.

Quantitative analysis of catechins in Saraca asoca and correlation with antimicrobial activity

Herbal medicines are highly complex and have unknown mechanisms in diseases treatment. Saraca asoca (Roxb.), De. Wild has been recommended to treat gynecological disorders and used in several commercial polyherbal formulations. In present study, efforts have been made to explore antimicrobial activity and its co-relation with the distributions of catechins in the organs of S. asoca using targeted MS/MS. Eight extracts (cold and hot water) from four different organs of S. asoca and two drugs were prepared and antimicrobial activity was assessed by microbroth dilution assay. Quantitative and qualitative analysis of catechins in crude extracts was done by using targeted and auto-MS/MS and correlated with antimicrobial activity. (+)-Catechin and (+)-epicatechin and their biosynthesis related compound were found to be up-regulated in regenerated bark and leaves extracts. (−)-Epigallocatechin was found to be significantly higher in bark water extract as compared to others but showed low antimicrobial activity. Result showed down-regulation of (−)-epigallocatechin and up-regulation of (+)-catechin and (+)-epicatechin in the regenerated bark and leaves of S. asoca. It might be the contributing factor in the antimicrobial activity of regenerated bark and leaves of the plant. The concentration of (+)-epicatechin in processed drugs (Ashokarishta) from Baidyanath was found to be seven times higher than that of Dabur Pvt. Ltd., but no antimicrobial activity was observed, indicating the variations among the plant based drugs. This will be helpful in rational use of S. asoca parts. Furthermore, the analytical method developed is sensitive, repeatable and reliable; therefore, it is suitable for quality control of herbal drugs.

Folk medicinal uses of Verbenaceae family plants in Bangladesh

Folk medicinal practitioners form the first tier of primary health-care providers to most of the rural population of Bangladesh. They are known locally as Kavirajes and rely almost solely on oral or topical administration of whole plants or plant parts for treatment of various ailments. Also about 2% of the total population of Bangladesh are scattered among more than twenty tribes residing within the country's borders. The various tribes have their own tribal practitioners, who use medicinal plants for treatment of diseases. The objective of the present survey was to conduct an ethnomedicinal survey among the Kavirajes and tribal practitioners to determine which species of plants belonging to the Verbenaceae family are used by the practitioners. The Verbenaceae family plants are well known for constituents having important bio-active properties. The present survey indicated that 13 species belonging to 8 genera are used by the folk and tribal medicinal practitioners of Bangladesh. A comparison of their folk medicinal uses along with published reports in the scientific literature suggests that the Verbenaceae family plants used in Bangladesh can potentially be important sources of lead compounds or novel drugs for treatment of difficult to cure debilitating diseases like malaria and rheumatoid arthritis.

Screening of antibacterial potentials of some medicinal plants from Melghat forest in India

Cyperus rotundus, Caesalpinia bonducella, Tinospora cordifolia, Gardenia gummifera, Ailanthus excelsa, Acacia arabica, Embelia ribes and Ventilago maderspatana from Melghat forest were screened for their antibacterial potential against Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Proteus vulgaris, Salmonella typhi, Shigella flexneri, Salmonella paratyphi, Salmonella typhimurium, Pseudomonas aeruginosa, Enterobacter aerogenes by disc diffusion method. Out of these medicinal plants Caesalpinia bonducella, Gardenia gummifera and Acacia arabica showed remarkable antibacterial potential. The phytochemical analysis had showed the presence of Cardiac glycosides in all extracts (aqueous, acetone, ethanol and methanol) of Acacia arabica, Gardenia gummifera and ethanol, methanol extracts of Caesalpinia bonducella. Flavonoids were present in Gardenia gummifera, Ailanthus excelsa and acetone, methanol extracts of Acacia Arabica. Tannins and phenolic were present in Cyperus rotundus, Embelia ribes, and organic extracts of Ventilago maderspatana.