Blechnum orientale Linn - a fern with potential as antioxidant, anticancer and antibacterial agent

Catharanthus roseus-assisted bio-fabricated zinc oxide nanoparticles for promising antibacterial potential against Klebsiella pneumoniae

This study emphasized on the synthesis of zinc oxide nanoparticles (ZnO NPs) in an environmentally friendly manner from the extract of Catharanthus roseus leaves and its antibacterial assessment against the pneumonia-causing pathogen Klebsiella pneumoniae. This simple and convenient phytosynthesis approach is found to be beneficial over conventional methods, wherein plants serve as excellent reducing, capping, and stabilizing agents that enables the formation of ZnO NPs without the use of harmful chemicals. The formation of ZnO NPs was confirmed through several characterization techniques such as UV-visible spectroscopy, XRD, FT-IR, SEM, HR-TEM, and EDX. XRD analysis revealed high polycrystallinity with crystallite size of approximately 13 nm. SEM and HR-TEM revealed the hexagonal structure of ZnO NPs with the particle size range of 20-50 nm. The EDX shows the elemental purity without any impurity. Furthermore, the antibacterial efficacy by the technique of disc diffusion exhibited clear inhibition zones in ZnO NPs-treated discs. In addition, 125 µg/mL of ZnO NP concentration showed minimum inhibition by the microbroth dilution method. The potent inhibitory activity was further validated with trypan blue dye exclusion and fluorescence microscopy. Finally, SEM examination confirmed the efficient antibacterial potential of ZnO NPs through disruption of the intact morphology of Klebsiella pneumoniae.

The traditional utilization, biological activity and chemical composition of edible fern species

ETHNOPHARMACOLOGICAL RELEVANCE

Ferns form an important part of the human diet. Young fern fiddleheads are mostly consumed as vegetables, while the rhizomes are often extracted for starch. These edible ferns are also often employed in traditional medicine, where all parts of the plant are used, mostly to prepare extracts. These extracts are applied either externally as lotions and baths or internally as potions, decoctions and teas. Ailments traditionally treated with ferns include coughs, colds, fevers, pain, burns and wounds, asthma, rheumatism, diarrhoea, or skin diseases (eczema, rashes, itching, leprosy).

AIM OF THE REVIEW

This review aims to compile the worldwide knowledge on the traditional medicinal uses of edible fern species correlating to reported biological activities and isolated bioactive compounds.

MATERIALS AND METHODS

The articles and books published on edible fern species were searched through the online databases Web of Science, Pubmed and Google Scholar, with critical evaluation of the hits. The time period up to the end of 2022 was included.

RESULTS

First, the edible fern species were identified based on the literature data. A total of 90 fern species were identified that are eaten around the world and are also used in traditional medicine. Ailments treated are often associated with inflammation or bacterial infection. However, only the most common and well-known fern species, were investigated for their biological activity. The most studied species are Blechnum orientale L., Cibotium barometz (L.) J. Sm., Diplazium esculentum (Retz.) Sw., Marsilea minuta L., Osmunda japonica Thunb., Polypodium vulgare L., and Stenochlaena palustris (Burm.) Bedd. Most of the fern extracts have been studied for their antioxidant, anti-inflammatory and antimicrobial activities. Not surprisingly, antioxidant capacity has been the most studied, with results reported for 28 edible fern species. Ferns have been found to be very rich sources of flavonoids, polyphenols, polyunsaturated fatty acids, carotenoids, terpenoids and steroids and most of these compounds are remarkable free radical scavengers responsible for the outstanding antioxidant capacity of fern extracts. As far as clinical trials are concerned, extracts from only three edible fern species have been evaluated.

CONCLUSIONS

The extracts of edible fern species exert antioxidant anti-inflammatory and related biological activities, which is consistent with their traditional medicinal use in the treatment of wounds, burns, colds, coughs, skin diseases and intestinal diseases. However, studies to prove pharmacological activities are scarce, and require chemical-biological standardization. Furthermore, correct botanical classification needs to be included in publications to simplify data acquisition. Finally, more in-depth phytochemical studies, allowing the linking of traditional use to pharmacological relevance are needed to be done in a standardized way.

Chemical composition, antioxidant and antibacterial activity of Piper chaba stem extracts with preservative effects on storage of raw beef patties

Piper chaba, a traditional South-east Asian medicinal herb and well-known curry spice, was studied to evaluate its suitability as a source of natural preservatives for beef products. Plant extracts that are high in phenolics and have high antimicrobial and antioxidant activities are likely to be useful as a natural preservative. Therefore, the phytochemical composition and the bioactivities of both ethanolic and methanolic extracts of P. chaba stem were examined first. The study revealed a significant antioxidant activities and potential antibacterial activity of P. chaba extracts. Next we investigated the preservation characteristics of P. chaba by using beef patties as a model system. Beef patties were produced and treated with 0.2 % ethanolic extract (mentioned as PEE) of P. chaba and 0.1 % commercial preservative (mentioned as PCP). They were then assessed for various storage quality parameters under refrigerated (4° C ± 1° C) conditions, including free fatty acid, antioxidant contents, and oxidative stability at 0, 6th, 16th, and 33rd days. No significant variations were observed across the products with regard to proximate composition study such as protein, ash and fat contents. In comparison to both PEE and PCP, the control product had higher free fatty acid values throughout the storage period. This indicates that the fat content of the PEE and PCP degraded at a slower rate than the control over the 33-day storage period. Our study also showed that both PCP and PEE had increased antioxidant capacity, implying that lipid oxidation is minimized. In contrast to the control, the oxidative stability of the P. chaba treated products was also higher. Altogether this study revealed that P. chaba could be utilized commercially, particularly in the food industry to preserve muscle foods.

Practical Applications

Natural preservatives are becoming more popular as a result of the different carcinogenic and toxic side effects of conventional preservatives. P. chaba, an exquisite culinary herb in Bangladesh, has long been used as a traditional medicine, because of its antimicrobial and antioxidant properties. This study revealed that P. chaba can be utilized as a food preservative, which opens up new possibilities for its development and use in functional foods.

Phytochemical Characterization and In Vitro and In Silico Biological Studies from Ferns of Genus Blechnum (Blechnaceae, Polypodiales)

The genus Blechnum represents one of the most ecologically and therapeutically important groups of ferns that grow in tropical, subtropical and temperate regions. In this work, the chemical fingerprint of lyophilized extracts of Blechnum chilense, B. hastatum, B. magellanicum and B. penna-marina species, the determination of their antioxidant activity through ORAC, FRAP and DPPH assays and inhibition of cholinesterase enzymes (AChE and BChE), and an in silico analysis of selected majority compounds on cholinesterase enzymes were identified. Nineteen compounds were recorded for B. chilense, nine in B. hastatum, seventeen in B. magellanicum and seventeen in B. penna-marina by liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UHPLC-ESI-QTOF-MS). The content of phenolic compounds, flavonoids, antioxidant activity and enzyme inhibition were variable among species, with best results for B. penna-marina. Molecular docking evidenced low toxicities, significant pharmacokinetic properties, and significant binding affinities of the tested compounds for the AChE and BChE enzymes. These fern species show high diversity of bioactive compounds and represent a promising resource in phytotherapy, especially for their optimal levels of phenolic compounds that support their antioxidant activity.

Traditional Uses, Phytochemistry, and Pharmacological Properties of the Genus Blechnum—A Narrative Review

Blechnum L. is a genus belonging to the Blechnaceae family with 236 accepted species that grow in intertropical, subtropical, and southern temperate regions. Several species of the genus have long been used in folk medicines to treat a broad spectrum of ailments, including typhoid, urinary infections, influenza, wounds, pulmonary complaints, blisters, boils, and antihelmintic-related complications. So far, about 91 chemical compounds have been isolated from different parts of 20 Blechnum species. Among these metabolites, phenolic compounds, sterols, and fatty acids are the main constituents. Modern pharmacological investigations revealed several isolated compounds and extracts to exhibit exceptional biological properties including the antioxidant, antimicrobial, anti-inflammatory, anticancer, insecticidal, antitrematocidal and wound healing. In various tests, both quercetin-7′,3′,4′-trimethoxy and phytol metabolites showed potential antioxidant and antitrematocidal properties, while ponasterone exhibited insecticidal activity. Despite having a broad range of traditional medicinal benefits and biological properties, understanding the scientific connotations based on the available data is still challenging. This article presents a comprehensive review of the traditional uses, phytochemical compounds, and pharmacological aspects of the Blechnum species.

Traditional Uses, Phytochemistry, and Pharmacological Properties of the Genus Blechnum—A Narrative Review

Blechnum L. is a genus belonging to the Blechnaceae family with 236 accepted species that grow in intertropical, subtropical, and southern temperate regions. Several species of the genus have long been used in folk medicines to treat a broad spectrum of ailments, including typhoid, urinary infections, influenza, wounds, pulmonary complaints, blisters, boils, and antihelmintic-related complications. So far, about 91 chemical compounds have been isolated from different parts of 20 Blechnum species. Among these metabolites, phenolic compounds, sterols, and fatty acids are the main constituents. Modern pharmacological investigations revealed several isolated compounds and extracts to exhibit exceptional biological properties including the antioxidant, antimicrobial, anti-inflammatory, anticancer, insecticidal, antitrematocidal and wound healing. In various tests, both quercetin-7′,3′,4′-trimethoxy and phytol metabolites showed potential antioxidant and antitrematocidal properties, while ponasterone exhibited insecticidal activity. Despite having a broad range of traditional medicinal benefits and biological properties, understanding the scientific connotations based on the available data is still challenging. This article presents a comprehensive review of the traditional uses, phytochemical compounds, and pharmacological aspects of the Blechnum species.

Phytochemical analysis and anticancer activity of Falcaria vulgaris Bernh growing in Moghan plain, northwest of Iran

Background

Falcaria vulgaris Bernh among the most important member of Apiaceae family has been used for medical investigation in Iran and some regions in the world. This plant possesses a range of coumarin and flavonoids compounds that have many therapeutic properties such as gastrointestinal and liver diseases, skin ulcers, gastric ulcers, and intestinal inflammation. It has also been found that these compounds lead to cytotoxic effects.

Objective

This study contains concentrates on the cytotoxic effect and induction of apoptosis on cancerous cells (SW-872) through various extracts and essential oil of Falcaria vulgaris Bernh. It considers the volatile compounds of effective samples.

Methods

The shoot of the plant was extracted by the Soxhlet apparatus and its essential oil was taken by the Clevenger apparatus. The cytotoxicity of the samples was evaluated by the MTT method and the mechanism of cancer cell death by flow cytometry and finally, the volatile compounds of essential oils and effective extracts were identified by GC-MS.

Results

The results demonstrated that n-Hexane extract and 40% VLC fraction had the greatest cytotoxic effect on SW-872 cells. While, the most abundant volatile compounds in essential oil and 40% VLC fraction of n-Hexane extract were terpenoid compounds like (+) spathulenol and caryophyllene oxide, in n-Hexane extract tetradecan, and spathulenol were the most, respectively.

Conclusion

The fraction of 40% n-Hexane was in a concentration-dependent manner and significantly with controlling cells inhibited the growth of cancer cells. A plausible explanation could be made to account for this effect. This inhibition was made through induction of apoptosis and due to the presence of effective volatile compounds such as terpenoids and non-terpenoids which could be considered as valuable natural sources for the isolation of anti-cancer compounds.

Isolation and characterization of endophytic fungi having plant growth promotion traits that biosynthesizes bacosides and withanolides under in vitro conditions

Endophytes are regarded with immense potentials in terms of plant growth promoting (PGP) elicitors and mimicking secondary metabolites of medicinal importance. Here in the present study, we explored Bacopa monnieri plants to isolate, identify fungal endophytes with PGP elicitation potentials, and investigate secretion of secondary metabolites such as bacoside and withanolide content under in vitro conditions. Three fungal endophytes isolated (out of 40 saponin producing isolates) from leaves of B. monnieri were examined for in vitro biosynthesis of bacosides. On morphological, biochemical, and molecular identification (ITS gene sequencing), the isolated strains SUBL33, SUBL51, and SUBL206 were identified as Nigrospora oryzae (MH071153), Alternaria alternata (MH071155), and Aspergillus terreus (MH071154) respectively. Among these strains, SUBL33 produced highest quantity of Bacoside A3 (4093 μg mL-1), Jujubogenin isomer of Bacopasaponin C (65,339 μg mL-1), and Bacopasaponin C (1325 μg mL-1) while Bacopaside II (13,030 μg mL-1) was produced by SUBL51 maximally. Moreover, these aforementioned strains also produced detectable concentration of withanolides-Withaferrin A, Withanolide A (480 μg mL-1), and Withanolide B (1024 μg mL-1) respectively. However, Withanolide A was not detected in the secondary metabolites of strain SUBL51. To best of our knowledge, the present study is first reports of Nigrospora oryzae as an endophyte in B. monnieri with potentials of biosynthesis of economically important phytomolecules under in vitro conditions.

Assessment of antibacterial, anti-inflammatory, and cytotoxic effects of different extracts of Gynura procumbens leaf

Background

In Southeast Asia, Gynura procumbens has been utilized as a traditional medicinal herb for many diseases. The nontoxic effects of the leaves of G procumbens can be consumed safely for the treatment of many diseases, especially diabetes mellitus.

Objectives

This study aimed to assess the antibacterial, anti-inflammatory, and cytotoxic effects of G procumbens leaves through different extracts.

Methods

Cold extraction was employed for G procumbens leaves. Disc diffusion, bovine serum albumin denaturation, brine shrimp lethality assays, and microscopic examination of tissues (ie, liver, kidney, and heart) were performed to measure antibacterial, anti-inflammatory, and cytotoxic activities, and histopathologic analysis, respectively.

Results

The distinct concentrations of aqueous, ethanol, and n-hexane extracts showed prominent antibacterial activity against four pathogenic bacterial strains (Chromobacterium sp, Staphylococcus aureus, Enterococcus faecium, and Escherichia coli 0157:H7:LT). The aqueous extract of G procumbens at a concentration of 200 µg/mL showed potential antibacterial activities against S aureus and E faecium, with mean (SD) zones of inhibition of 15 (1.0) mm and 10 (0.55) mm, respectively. At a concentration of 40 µg/mL, the aqueous extract of G procumbens exhibited significant (P < 0.01) anti-inflammatory activity compared with that of the other 2 extracts in the bovine serum albumin denaturation assay. The n-hexane extract showed moderate cytotoxic activity compared with that of vincristine sulfate. The median lethal concentration values of the aqueous, ethanol, and n-hexane extracts were 427.66, 218.56, and 114.51 μg/mL, respectively. The aqueous extract exhibited lower cytotoxicity than that exhibited by the ethanol and n-hexane extracts. The histopathologic analysis results showed that the aqueous extract of G procumbens had no harmful effects on the different organs of the experimental mice.

Conclusions

The aqueous extract of G procumbens could be a potential source for treating various infectious and chronic diseases. (Curr Ther Res Clin Exp. 2021; 82:XXX–XXX)

Antimicrobial activity, phytochemical characterization and gas chromatography-mass spectrometry analysis of Aspilia pluriseta Schweinf. extracts

Aspilia pluriseta is associated with various bioactivities, although with limited scientific justification. In this study, we evaluated the antimicrobial activity, and characterized the phytochemicals of root extracts of A. pluriseta aimed at validating its therapeutic potential. We used BACTEC MGIT™ 960 system to test for antitubercular activity, disc-diffusion together with the microdilution method to evaluate antimicrobial activities and qualitative phytochemical tests together with gas chromatography-mass spectrometry (GC-MS) analysis to determine the phytochemicals that associated with A. pluriseta extracts activity. We show that methanolic crude extract (at 1 g/mL) had high Mycobacterium tuberculosis (MTB) inhibitory activity (0 growth unit) and considerable potency against Escherichia coli (11.7 mm), Staphylococcus aureus (9.0 mm), and Candida albicans (7.7 mm). All the extract fractions exerted remarkable antimycobacterial activities with minimum inhibitory activity of between 6.26 – 25 μg/mL. The highest antimicrobial activity of petroleum ether and dichloromethane fraction was against E. coli at inhibition zone diameters of 8.3 mm, and 8.0 mm, respectively, while ethyl acetate fraction was against S. aureus with an inhibition zone of 8.7 mm. Methanolic fraction exhibited broad-spectrum activity against 87.5% of the tested microbes (inhibition zones 6.3–8.3 mm). Furthermore, we qualitatively detected terpenoids, alkaloids, and phenolics such as flavonoids, and anthraquinones in extract fractions. GC-MS analysis detected an abundance of fatty acid esters, 2-hydroxy-1-(hydroxymethyl) ethyl ester-hexadecanoic acid, and 2,3-dihydroxy propyl ester-octadecanoic acid and four alkanes. Taken together, we show that A. pluriseta extract fractions (especially ethyl acetate and methanolic fractions) have strong selective antitubercular activity, and thus, we scientifically validate the use of A. pluriseta as a potential source for the discovery of novel antitubercular agents.

Biological and toxicological evaluation of Rhus trilobata Nutt. (Anacardiaceae) used traditionally in mexico against cancer

BACKGROUND

Rhus trilobata Nutt. (Anacardiaceae) (RHTR) is a plant of Mexico that is traditionally used as an alternative treatment for several types of cancer. However, the phytochemical composition and potential toxicity of this plant have not been evaluated to support its therapeutic use. Therefore, this study aimed to evaluate the biological activity of RHTR against colorectal adenocarcinoma cells, determine its possible acute toxicity, and analyze its phytochemical composition.

METHODS

The traditional preparation was performed by decoction of stems in distilled water (aqueous extract, AE), and flavonoids were concentrated with C18-cartridges and ethyl acetate (flavonoid fraction, FF). The biological activity was evaluated by MTT viability curves and the TUNEL assay in colorectal adenocarcinoma (CACO-2), ovarian epithelium (CHO-K1) and lung/bronchus epithelium (BEAS-2B) cells. The toxicological effect was determined in female BALB/c mice after 24 h and 14 days of intraperitoneal administration of 200 mg/kg AE and FF, respectively. Later, the animals were sacrificed for histopathological observation of organs and sera obtained by retro-orbital bleeding for biochemical marker analysis. Finally, the phytochemical characterization of AE and FF was conducted by UPLC-MSE.

RESULTS

In the MTT assays, AE and FF at 5 and 18 μg/mL decreased the viability of CACO-2 cells compared with cells treated with vehicle or normal cells (p ≤ 0.05, ANOVA), with changes in cell morphology and the induction of apoptosis. Anatomical and histological analysis of organs did not reveal important pathological lesions at the time of assessment. Additionally, biochemical markers remained normal and showed no differences from those of the control group after 24 h and 14 days of treatment (p ≤ 0.05, ANOVA). Finally, UPLC-MSE analysis revealed 173 compounds in AE-RHTR, primarily flavonoids, fatty acids and phenolic acids. The most abundant compounds in AE and FF were quercetin and myricetin derivates (glycosides), methyl gallate, epigallocatechin-3-cinnamate, β-PGG, fisetin and margaric acid, which might be related to the anticancer properties of RHTR.

CONCLUSION

RHTR exhibits biological activity against cancer cells and does not present adverse toxicological effects during its in vivo administration, supporting its traditional use.

A review on medicinal plant extracts and their active ingredients against methicillin-resistant and methicillin-sensitive Staphylococcus aureus

Staphylococcus aureus is among the pathogens capable of developing a broad spectrum of infections in human beings. In addition to the hospital, the bacterium is present in the community and has a high resistance to antibiotics, which is also increasing on an ongoing basis. Resistance to β-lactam antibiotic family is one of the concerns about the bacterium that has encountered the treatment of such infections with difficulty. Due to the increased resistance and importance of this bacterium, new strategies are needed to control this pathogen. One of these approaches is the use of medicinal plants, which has attracted many researchers in the last decade. Several studies have been carried out or are being designed using various herbs to find active ingredients to deal with this bacterium. The aim of this study was to present the antibacterial activity of different medicinal plants and the effects of their active ingredients on methicillin-resistant and methicillin-sensitive S. aureus and to clarify the pathway to further studies in this regard.

Identification of Potential Anticancer Protein Targets in Cytotoxicity Mediated by Tropical Medicinal Fern Extracts

Background:

Medicinal fern species represent a potentially important source for both food and medicinal applications. Previously, two underutilized tropical fern species (Blechnum orientale and Phymatopteris triloba) were reported with cytotoxic activities against selected cancer cell lines. However, the exact mechanism remains elusive.

Objective:

In this paper, we reported the identification of six differentially expressed proteins isolated from cancer cells, following exposure to the cytotoxic fern extracts.

Materials and Methods:

The identities of these cancer proteins were determined by matrix-assisted laser desorption ionization time-of-flight protein sequencing.

Results:

The cancer proteins were identified as follows: elongation factor 1-γ, glyceraldehydes-3-phosphate dehydrogenase, heat shock protein 90-β, heterogeneous nuclear ribonucleoprotein-A2/B1, truncated nucleolar phosphoprotein B23, and tubulin-β chain. To the best of our knowledge, this paper represents the first time these cancer proteins are being reported, following exposure to the aforementioned cytotoxic fern extracts.

Conclusion:

It is hoped that further efforts in this direction could lead to the identification and development of target-specific chemotherapeutic agents.

SUMMARY

Cytotoxic fern extracts were tested in anti-cancer proteomic works.

Six differentially-expressed cancer proteins were identified.

Potential anti-cancer protein targets were reported.

Abbreviations used: EF: Elongation factor; HRP: Horseradish peroxidase; HSP: Heat shock protein; MALDI: Matrix-assisted laser desorption/ionization.

A review of the use of pteridophytes for treating human ailments

The aim of this review was to explore the pharmacological activity of early tracheophytes (pteridophytes) as an alternative medicine for treating human ailments. As the first vascular plants, pteridophytes (aka, ferns and fern allies) are an ancient lineage, and human beings have been exploring and using taxa from this lineage for over 2000 years because of their beneficial properties. We have documented the medicinal uses of pteridophytes belonging to thirty different families. The lycophyte Selaginella sp. was shown in earlier studies to have multiple pharmacological activity, such as antioxidant, anti-inflammatory, anti-cancer, antidiabetic, antiviral, antimicrobial, and anti-Alzheimer properties. Among all the pteridophytes examined, taxa from the Pteridaceae, Polypodiaceae, and Adiantaceae exhibited significant medicinal activity. Based on our review, many pteridophytes have properties that could be used in alternative medicine for treatment of various human illnesses. Biotechnological tools can be used to preserve and even improve their bioactive molecules for the preparation of medicines against illness. Even though several studies have reported medicinal uses of ferns, the possible bioactive compounds of several pteridophytes have not been identified. Furthermore, their optimal dosage level and treatment strategies still need to be determined. Finally, the future direction of pteridophyte research is discussed.

Identification of compounds from non-polar fractions of Blechnum spp and a multitarget approach involving enzymatic modulation and oxidative stress

OBJECTIVES

The hexane (HEX) and dichloromethane (DCM) fractions from Blechnum binervatum, Blechnum brasiliense and Blechnum occidentale were studied about phytochemicals and biological properties using multitarget approach.

METHODS

The chemical composition was performed by gas chromatography coupled with mass spectrometry detector (GC-MS) analysis. Antioxidant capacity was evaluated against free radicals and on lipid peroxidation. Monoamine oxidases (MAO) and cholinesterases enzymatic modulation, as well as effects on rat and human cells, were assessed.

KEY FINDINGS

The CG-MS analysis allowed the identification of a non-polar compound series, being neophytadiene the major constituent in all DCM fractions and in HEX fractions from B. binervatum and B. occidentale. In B. brasiliense HEX fraction, β-sitosterol was the main compound. In general, B. brasiliense DCM fraction presented the highest antioxidant activity, with IC₅₀ values around 9, 2 and 1.2 times lower than those found for the other species, against HO˙, NO˙ and on lipid peroxidation, respectively. Regarding enzyme modulations, B. brasiliense DCM fraction presented higher MAO-A inhibition (IC₅₀ : 31.83 μg/ml), with a better selectivity index (SI MAO-A/MAO-B: 6.77). The lack of harmful effects was observed in rat cells, also highlighted in the stem cells for all Blechnum samples.

CONCLUSION

These findings encourage the search for multibinding natural products, mainly from B. brasiliense DCM fraction.

Treatment for diabetic ulcer wounds using a fern tannin optimized hydrogel formulation with antibacterial and antioxidative properties

ETHNOPHARMACOLOGICAL RELEVANCE

Blechnum orientale Linn. (B. orientale) is a fern traditionally used by the natives as a poultice to treat wounds, boils, ulcers, blisters, abscesses, and sores on the skin.

AIM OF THE STUDY

To investigate the wound healing ability of a concentrated extract of B. orientale in a hydrogel formulation in healing diabetic ulcer wounds.

MATERIALS AND METHODS

The water extract from the leaves of B. orientale was separated from the crude methanolic extract and subjected to flash column chromatography techniques to produce concentrated fractions. These fractions were tested for phytochemical composition, tannin content, antioxidative and antibacterial activity. The bioactive fraction was formulated into a sodium carboxymethylcellulose hydrogel. The extract-loaded hydrogels were then characterized and tested on excision ulcer wounds of streptozotocin-induced diabetic rats. Wound size was measured for 14 days. Histopathological studies were conducted on the healed wound tissues to observe for epithelisation, fibroblast proliferation and angiogenesis. All possible mean values were subjected to statistical analysis using One-way ANOVA and post-hoc with Tukey's T-test (P<0.05).

RESULTS

One fraction exhibited strong antioxidative and antibacterial activity. The fraction was also highly saturated with tannins, particularly condensed tannins. Fraction W5-1 exhibited stronger antioxidant activity compared to three standards (α-Tocopherol, BHT and Trolox-C). Antibacterial activity was also present, and notably bactericidal towards Methicillin-resistant Staphylococcus aureus (MRSA) at 0.25mg/ml. The extract-loaded hydrogels exhibited shear-thinning properties, with high moisture retention ability. The bioactive fraction at 4% w/w was shown to be able to close diabetic wounds by Day 12 on average. Other groups, including controls, only exhibited wound closure by Day 14 (or not at all). Histopathological studies had also shown that extract-treated wounds exhibited re-epithelisation, higher fibroblast proliferation, collagen synthesis, and angiogenesis.

CONCLUSION

The ethnopharmacological effects of using B. orientale as a topical treatment for external wounds was validated and was also significantly effective in treating diabetic ulcer wounds. Thus, B. orientale extract hydrogel may be presented as a potential treatment for diabetic ulcer wounds.

Combining in vitro and in silico approaches to evaluate the multifunctional profile of rosmarinic acid from Blechnum brasiliense on targets related to neurodegeneration

Natural products are important sources of chemical diversity leading to unique scaffolds that can be exploited in the discovery of new drug candidates or chemical probes. In this context, chemical and biological investigation of ferns and lycophytes occurring in Brazil is an approach adopted by our research group aiming at discovering bioactive molecules acting on neurodegeneration targets. In the present study, rosmarinic acid (RA) isolated from Blechnum brasiliense showed an in vitro multifunctional profile characterized by antioxidant effects, and monoamine oxidases (MAO-A and MAO-B) and catechol-O-methyl transferase (COMT) inhibition. RA showed antioxidant effects against hydroxyl (HO(•)) and nitric oxide (NO) radicals (IC50 of 29.4 and 140 μM, respectively), and inhibition of lipid peroxidation (IC50 of 19.6 μM). In addition, RA inhibited MAO-A, MAO-B and COMT enzymes with IC50 values of 50.1, 184.6 and 26.7 μM, respectively. The MAO-A modulation showed a non-time-dependent profile, suggesting a reversible mechanism of inhibition. Structural insights on RA interactions with MAO-A and COMT were investigated by molecular docking. Finally, RA (up to 5 mM) demonstrated no cytotoxicity on polymorphonuclear rat cells. Taken together, our results suggest that RA may be exploited as a template for the development of new antioxidant molecules possessing additional MAO and COMT inhibition effects to be further investigated on in vitro and in vivo models of neurodegenerative diseases.

Antimicrobial and cytotoxicity properties of the organic solvent fractions of Clerodendrum myricoides (Hochst.) R. Br. ex Vatke: Kenyan traditional medicinal plant

Background/Aim:

Clerodendrum myricoides is a Kenyan herbal plant used in the management of respiratory diseases. In the current study, we investigated in vitro antimicrobial activity, cytotoxicity, and phytochemical screening of C. myricoides

Materials and Methods:

Antimicrobial activities of C. myricoides organic fractions against array of microorganisms including: (i) Mycobacterium tuberculosis (MTB) H37Rv, (ii) Staphylococcus aureus, (iii) Klebsiella pneumoniae, (iv) Escherichia coli, (v) Candida albicans, (vi) Pseudomonas aeruginosa, (vii) Cryptococcus neoformans, (viii) Salmonella typhi, (ix) Shigella sonnei, and (x) Methicillin-resistant S. aureus (MRSA) were investigated by disc diffusion and microdilution techniques. Antituberculous activity was investigated using BACTEC MGIT 960 system while cytotoxicity was analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on HEp-2 cells. Finally, phytochemicals were screened using standard procedures.

Results:

Methanolic fractions exhibited a broad spectrum activity inhibiting 75% of test pathogens. It had the highest activity with minimal inhibition concentration (MIC) values of ≤62.5 µg/ml recorded against 62.5% tested microbes. It yielded the highest zone of inhibition of 20.3 mm (S. aureus), lowest MIC of <12.5 µg/ml (MTB), and the lowest minimal bactericidal concentration of 62.5 µg/ml (C. albicans), within the acceptable toxicity limit (CC₅₀ >90 µg/ml). The phytochemicals largely believed to be responsible for the observed activity included: Alkaloid, phenols, anthraquinones, terpenoids, and flavonoids.

Conclusion:

Methanolic fraction had remarkable activity against MRSA, S. aureus, E. coli, S. sonnei, C. albicans, and MTB, which are of public health concerns due to drug resistance and as sources of community and nosocomial infections. To the best of our knowledge, this is the first report exploring the antituberculous activity of C. myricoides and thence a major output in search of novel, safe drug leads to mitigate the global tuberculosis threat.

Antimicrobial and cytotoxicity properties of the crude extracts and fractions of Premna resinosa (Hochst.) Schauer (Compositae): Kenyan traditional medicinal plant

Background

Premna resinosa (Hochst.) Schauer also called “mukarakara” in Mbeere community of Kenya is used in the management of respiratory illness. In this study we investigated antituberculous, antifungal, antibacterial activities including cytotoxicity and phytochemical constituents of this plant.

Methods

Antibacterial and antifungal activities were investigated by disc diffusion and micro dilution techniques. Antituberculous activity was investigated using BACTEC MGIT 960 system while cytotoxicity was analyzed by MTT assay on Vero cells (Methanolic crude extract) and HEp-2 cells (fractions). Finally, phytochemicals were profiled using standard procedures.

Results

P. resinosa had high antituberculous activity with a MIC of <6.25 μg/ml in ethyl acetate fraction. The antibacterial activity was high and broad spectrum, inhibiting both Gram positive and Gram negative bacteria. Dichloromethane fraction had the best antibacterial MIC of 31.25 μg/ml against Methicillin-resistant S. aureus while Ethyl acetate fraction had the highest zone of inhibition of 22.3 ± 0.3 against S. aureus. Its effects on tested fungi were moderate with petro ether fraction giving an inhibition of 10.3 ± 0.3 on C. albicans. The crude extract and two fractions (petro ether and methanol) were not within the acceptable toxicity limits, however dichloromethane and ethyl acetate fractions that exhibited higher activity were within the acceptable toxicity limit (CC₅₀ < 90). The activity can to some extent be associated to alkaloids, flavonoids, terpenoids, anthraquinones and phenols detected in this plant extracts.

Conclusion

Our findings demonstrate that P. resinosa has high selective potential as a source of novel lead for antituberculous, antibacterial and antifungal drugs. Of particular relevance is high activity against MRSA, S. aureus, C. albicans and MTB which are great public health challenge due to drug resistance development and as major sources of community and hospital based infections.

Alhagi: a plant genus rich in bioactives for pharmaceuticals

Alhagi, a plant genus from family Fabaceae, is widely distributed in many countries of Asia, Australia and Europe. Commonly known as camel thorn, Alhagi has many species famous for feed and folk medicinal uses. Different species of Alhagi such as Alhagi pseudalhagi, A. graecorum, A. sparsifolia, A. kirgisorum, A. maurorum, A. camelorum and A. persarum have been explored for their antioxidant potential and nutritive value along with various medicinal properties. A wide array of pharmacologically active secondary metabolites such as flavonoids, alkaloids (alhacidin and alhacin), steroids, pseudalhagin A, phospholipids and polysaccharides have been reported from different parts of Alhagi species. A broad range of biological activities such as antioxidant, cardiovascular, anti-ulcer, hepatoprotective, antispasmodic, antidiarrheal, antinociceptive, antipyretic, anti-inflammatory, anti-rheumatic, antibacterial and antifungal have been ascribed to different parts of Alhagi. In addition, Alhagi plants are also valued as a rich source of digestible protein and important minerals. This review focuses on the medicinal applications and detailed profile of high-value bioactive phytochemicals along with pharmacological attributes and therapeutic potential of these multi-purpose plants.

In-Vitro and in-Silico characterization of Sophora interrupta plant extract as an anticancer activity

Sophora interrupta belongs to the family of Fabaceae and the species in this genus have a diverse medicinal importance as a folk medicine for preventing many ailments including cancer. In order to evaluate the anticancer activity of S.interrupta, we have performed in vitro anti-oxidant, anti-inflammatory, anti-proliferative, and cell based anticancer activity in MCF-7 and PC-3 cell lines. Secondary metabolites of S.interrupta were used to identify anticancer compounds using Open Eye software. The antioxidant activity of the S.interrupta root ethylacetate (SEA) extract at 100 µg/ml is equal to that of ascorbic acid at 50 µg/ml. The antiinflammatory activity of SEA is half of that of diclofenac at 50 µg/ml. Anticancer activity was detected by measuring the mitochondrial dehydrogenase activity (MTT assay). The half maximal inhibitory concentrations (IC₅₀) for MCF-7 and PC-3 cell lines are 250 and 700 µg/ml respectively. This was supported by the morphological changes such as membrane blebbing, cell detachment and rounded cell morphology when compared to the parental cells. In addition, we observed few green cells (live) over red cells (dead) based on the uptake of acridine orange and ethidium bromide dyes. Kaempferol-3-O-b-D-glucopyranoside, a Secondary metabolite of S.interrupta form 6 hydrogen bond interactions with Arg 202, Gln 207, Gly 227, Gly 229, Thr 231 and Ala 232 human DEAD box RNA helicase, DDX3 protein and is equivalent to crystal structure of adenosine mono phosphate to DDX3. Overall, it suggests that the SEA extract has anticancer compounds, and it can be used to enhance death receptor mediated cancer cell death.

Synergy of antibacterial and antioxidant activities from crude extracts and peptides of selected plant mixture

BACKGROUND

A plant mixture containing indigenous Australian plants was examined for synergistic antimicrobial activity using selected test microorganisms. This study aims to investigate antibacterial activities, antioxidant potential and the content of phenolic compounds in aqueous, ethanolic and peptide extracts of plant mixture.

METHODS

Well diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays were used to test antibacterial activity against four pathogenic bacteria namely Staphylococcus aureus, Escherichia coli, Bacillus cereus, and Pseudomonas aeruginosa. DPPH (2, 2-diphenyl-1- picrylhydrazyl) and superoxide dismutase (SOD) assays were used to evaluate antioxidant activity. HPLC and gel filtration were used for purification of the peptides. Scanning electron microscope was applied to investigate the mode of attachment of the peptides on target microbial membranes.

RESULTS

Aqueous extraction of the mixture showed no inhibition zones against all the test bacteria. Mean diameter of inhibition zones for ethanol extraction of this mixture attained 8.33 mm, 7.33 mm, and 6.33 mm against S. aureus at corresponding concentrations of 500, 250 and 125 mg/ml while E .coli showed inhibition zones of 9.33 mm, 8.00 mm and 6.66 mm at the same concentrations. B. cereus exhibited inhibition zones of 11.33 mm, 10.33 mm and 10.00 mm at concentrations of 500, 250 and 125 mg/ml respectively. The peptide extract demonstrated antibacterial activity against S. aureus, E. coli and B. cereus. The MIC and MBC values for ethanol extracts were determined at 125 mg/ml concentration against S. aureus and E. coli and B. cereus value was 31.5 mg/ml. MIC and MBC values showed that the peptide extract was significantly effective at low concentration of the Australian plant mixture (APM). Phenolic compounds were detected in hot aqueous and ethanolic extracts of the plant mixture. Hot aqueous, ethanol and peptides extracts also exhibited antioxidant activities.

CONCLUSIONS

It was concluded that APM possessed good antibacterial and antioxidant activities following extraction with different solvents. The results suggest that APM provide a new source with antibacterial agents and antioxidant activity for nutraceutical or medical applications.

Ferns and lycopods--a potential treasury of anticancer agents but also a carcinogenic hazard

Many species of seedless vascular plants-ferns and lycopods-have been used as food and folk medicine since ancient times. Some of them have become the focus of intensive research concerning their anticancer properties. Studies on the anticancer effect of crude extracts are being increasingly replaced by bioactivity-guided fractionation, as well as detailed assessment of the mechanism of action. Numerous compounds-especially flavonoids such as amentoflavone and protoapigenone, and also simpler phenolic compounds, steroids, alkaloids and terpenoids-were isolated and found to be cytotoxic, particularly pro-apoptotic, or to induce cell cycle arrest in cancer cell lines in vitro. In in vivo experiments, some fern-derived compounds inhibited tumour growth with little toxicity. On the other hand, many ferns-not only the well-known Bracken (Pteridium)-may pose a significant hazard to human health due to the fact that they contain carcinogenic sesquiterpenoids and their analogues. The objective of this review is to summarise the recent state of research on the anticancer properties of ferns and lycopods, with a focus on their characteristic bioactive constituents. The carcinogenic hazard posed by ferns is also mentioned.

Absorption of Hazardous Pollutants by a Medicinal FernBlechnum orientaleL

A Chinese medicinal fernBlechnum orientale(Linn) was separately collected from polluted and unpolluted sites to determine whether it could accumulate hazardous pollutants or not. Metal concentrations (Cu, Zn, Mn, Pb, Cd, Cr, As, and Hg) both in the fronds and roots and polycyclic aromatic hydrocarbons (PAHs) in the fronds of this fern were quantified. At both sites, roots ofB. orientalehad significantly higher heavy metals than the fronds. Concentrations of Pb, As, Hg, Cd, and Cu in the fronds at the polluted site were more than 2, 6, 7, 14, 5, and 13 times of those at the unpolluted site. Translocation factor and bioaccumulation factor implied thatB. orientaledid not have a good ability to transport heavy metals from the roots to the fronds. Total PAHs in the fronds at the polluted site were significantly higher than those at the unpolluted site, indicating the physiological PAHs absorption byB. orientalegrowing at polluted sites. Uptake of pollutants via stomata might be the main reason causing the significant accumulation of hazardous pollutants in the fronds ofB. orientale. Large-scale systematical survey and intensive monitoring on pollutants in this medicinal fern should be necessarily strengthened.

Potential dermal wound healing agent in Blechnum orientale Linn

BACKGROUND

Blechnum orientale Linn. (Blechnaceae) is used ethnomedicinally to treat wounds, boils, blisters or abscesses and sores, stomach pain and urinary bladder complaints. The aim of the study was to validate the ethnotherapeutic claim and to evaluate the effects of B. orientale water extract on wound healing activity.

METHODS

Water extract of B. orientale was used. Excision wound healing activity was examined on Sprague-Dawley rats, dressed with 1% and 2% of the water extract. Control groups were dressed with the base cream (vehicle group, negative control) and 10% povidone-iodine (positive control) respectively. Healing was assessed based on contraction of wound size, mean epithelisation time, hydroxyproline content and histopathological examinations. Statistical analyses were performed using one way ANOVA followed by Tukey HSD test.

RESULTS

Wound healing study revealed significant reduction in wound size and mean epithelisation time, and higher collagen synthesis in the 2% extract-treated group compared to the vehicle group. These findings were supported by histolopathological examinations of healed wound sections which showed greater tissue regeneration, more fibroblasts and angiogenesis in the 2% extract-treated group.

CONCLUSIONS

The ethnotherapeutic use of this fern is validated. The water extract of B. orientale is a potential candidate for the treatment of dermal wounds. Synergistic effects of both strong antioxidant and antibacterial activities in the extract are deduced to have accelerated the wound repair at the proliferative phase of the healing process.

Assessment of phytochemical content, polyphenolic composition, antioxidant and antibacterial activities of Leguminosae medicinal plants in Peninsular Malaysia

Background

Many medicinal plants from Leguminosae family can be found easily in Malaysia. These plants have been used as traditional medicines by local ethnic groups, where they are prepared as decoction, pastes for wound infections, and some have been eaten as salad. This paper focused on the assessment of antioxidant potential, antibacterial activity and classes of phytochemicals of nine plants from the Leguminosae family.

Methods

Acacia auriculiformis, Bauhinia kockiana, Bauhinia purpurea, Caesalpinia pulcherrima, Calliandra tergemina, Cassia surattensis, Leucaena leucocephala, Peltophorum pterocarpum, and Samanea saman were extracted with aqueous methanol and dichloromethane:methanol mixture to test for antioxidant and antibacterial activities. The Folin-Ciocalteu assay was conducted to quantify the total phenolic content and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to determine the free radical quenching capacity. Antibacterial activity was assessed using disc diffusion (Kirby-Bauer) assay. Screening for major classes of phytochemical was done using standard chemical tests.

Results

B. kockiana flowers and C. pulcherrima leaves contained high total phenolic content (TPC) and strong DPPH radical scavenging ability with TPC of 8280 ± 498 mg GAE/100 g, IC₅₀ of 27.0 ± 5.0 μg/mL and TPC of 5030 ± 602 mg GAE/100 g, IC₅₀ of 50.0 ± 5.0 μg/mL respectively. Positive correlation was observed between TPC and free radical scavenging ability. Most extracts showed antibacterial activity against Gram positive bacteria at 1 mg, while none showed activity against Gram negative bacteria at the same dose. All extracts (except Samanea saman flower) showed antibacterial activity against two strains of methicillin resistant Staphylococcus aureus (MRSA) with MID values ranging between 100 μg/disc and 500 μg/disc.

Conclusion

The potential source of antioxidant and antibacterial agents, especially for MRSA infection treatments were found in B. kockiana, C. pulcherrima, C. tergemina and P. pterocarpum. These preliminary results would be a guide in the selection of potential candidates for further pharmacological study and in search of new drug candidate in treating MRSA infections.

Assessment of antiproliferative and antiplasmodial activities of five selected Apocynaceae species

Background

Studies have shown that the barks and roots of some Apocynaceae species have anticancer and antimalarial properties. In this study, leaf extracts of five selected species of Apocynaceae used in traditional medicine (Alstonia angustiloba, Calotropis gigantea, Dyera costulata, Kopsia fruticosa and Vallaris glabra) were assessed for antiproliferative (APF) and antiplasmodial (APM) activities, and analysed for total alkaloid content (TAC), total phenolic content (TPC) and radical-scavenging activity (RSA). As V. glabra leaf extracts showed wide spectrum APF and APM activities, they were further screened for saponins, tannins, cardenolides and terpenoids.

Methods

APF and APM activities were assessed using the sulphorhodamine B and lactate dehydrogenase assays, respectively. TAC, TPC and RSA were analysed using Dragendorff precipitation, Folin-Ciocalteu and DPPH assays, respectively. Screening for saponins, tannins, cardenolides and terpenoids were conducted using the frothing, ferric chloride, Kedde and vanillin-H₂SO₄ tests, respectively.

Results

Leaf extracts of A. angustiloba, C. gigantea and V. glabra displayed positive APF activity. Dichloromethane (DCM) extract of C. gigantea, and DCM and DCM:MeOH extracts of V. glabra showed strong APF activity against all six human cancer cell lines tested. DCM extract of A. angustiloba was effective against three cancer cell lines. Against MCF-7 and MDA-MB-231 cell lines, DCM extract of C. gigantea was stronger than standard drugs of xanthorrhizol, curcumin and tamoxifen. All five species were effective against K1 strain of Plasmodium falciparum and three species (C. gigantea, D. costulata and K. fruticosa) were effective against 3D7 strain. Against K1 strain, all four extracts of V. glabra displayed effective APM activity. Extracts of D. costulata were effective against 3D7 strain. Selectivity index values of extracts of A. angustiloba, C. gigantea and V. glabra suggested that they are potentially safe for use to treat malaria. Extracts of K. fruticosa had the highest TAC while D. costulata had the highest TPC and RSA. Phytochemical screening of extracts of V. glabra also showed the presence of terpenoids, tannins and saponins.

Conclusions

Leaf extracts of C. gigantea and V. glabra showed great promise as potential candidates for anticancer drugs as they inhibited the growth of all six cancer cell lines. Against K1 strain of P. falciparum, all four extracts of V. glabra displayed effective APM activity. The wide spectrum APF and APM activities of V. glabra are reported for the first time and this warrants further investigation into its bioactive compounds.

Oxidative DNA damage preventive activity and antioxidant potential of plants used in Unani system of medicine

BACKGROUND

There is increasing recognition that many of today's diseases are due to the "oxidative stress" that results from an imbalance between the formation and neutralization of reactive molecules such as reactive oxygen species (ROS) and reactive nitrogen species (RNS), which can be removed with antioxidants. The main objective of the present study was to evaluate the antioxidant activity of plants routinely used in the Unani system of medicine. Several plants were screened for radical scavenging activity, and the ten that showed promising results were selected for further evaluation.

METHODS

Methanol (50%) extracts were prepared from ten Unani plants, namely Cleome icosandra, Rosa damascena, Cyperus scariosus, Gardenia gummifera, Abies pindrow, Valeriana wallichii, Holarrhena antidysenterica, Anacyclus pyrethrum, Asphodelus tenuifolius and Cyperus scariosus, and were used to determine their total phenolic, flavonoid and ascorbic acid contents, in vitro scavenging of DPPH(·), ABTS(·+), NO, (·)OH, O₂(·-) and ONOO(⁻), and capacity to prevent oxidative DNA damage. Cytotoxic activity was also determined against the U937 cell line.

RESULTS

IC₅₀ values for scavenging DPPH(·), ABTS(·+), NO, (·)OH, O₂(·⁻) and ONOO(⁻) were in the ranges 0.007 ± 0.0001 - 2.006 ± 0.002 mg/ml, 2.54 ± 0.04 - 156.94 ± 5.28 μg/ml, 152.23 ± 3.51 - 286.59 ± 3.89 μg/ml, 18.23 ± 0.03 - 50.13 ± 0.04 μg/ml, 28.85 ± 0.23 - 537.87 ± 93 μg/ml and 0.532 ± 0.015 - 3.39 ± 0.032 mg/ml, respectively. The total phenolic, flavonoid and ascorbic acid contents were in the ranges 62.89 ± 0.43 - 166.13 ± 0.56 mg gallic acid equivalent (GAE)/g extract, 38.89 ± 0.52 - 172.23 ± 0.08 mg quercetin equivalent (QEE)/g extract and 0.14 ± 0.09 - 0.98 ± 0.21 mg AA/g extract. The activities of the different plant extracts against oxidative DNA damage were in the range 0.13-1.60 μg/ml. Of the ten selected plant extracts studied here, seven - C. icosandra, R. damascena, C. scariosus, G. gummifera, A. pindrow, V. wallichii and H. antidysenterica - showed moderate antioxidant activity. Finally, potentially significant oxidative DNA damage preventive activity and antioxidant activity were noted in three plant extracts: C. icosandra, R. damascena and C. scariosus. These three plant extracts showed no cytotoxic activity against U937 cells.

CONCLUSIONS

The 50% methanolic extracts obtained from different plant parts contained significant amounts of polyphenols with superior antioxidant activity as evidenced by the scavenging of DPPH(·), ABTS(·+), NO, (·)OH, O₂(·⁻) and ONOO(⁻). C. icosandra, R. damascena and C. scariosus showed significant potential for preventing oxidative DNA damage and radical scavenging activity, and the G. gummifera, A. pindrow, V. wallichii, H. antidysenterica, A. pyrethrum, A. tenuifolius and O. mascula extracts showed moderate activity. The extracts of C. icosandra, R. damascena and C. scariosus showed no cytotoxicity against U937 cells. In conclusion, these routinely used Unani plants, especially C. icosandra, R. damascena and C. scariosus, which are reported to have significant activity against several human ailments, could be exploited as potential sources of natural antioxidants for plant-based pharmaceutical industries.