Antioxidant and antimicrobial properties of polyphenolics from Withania adpressa (Coss.) Batt. against selected drug-resistant bacterial strains

Withania adpressa (Coss.) Batt. (W. adpressa) is a wild medicinal plant in the family Solanaceae, which is used as an alternative medicine. The present study aims to investigate the chemical composition, antioxidant, and antibacterial potentials of polyphenol-rich fraction from the leaves of W. adpressa. Polyphenol-rich fraction was characterized by use of high-performance liquid chromatography (HPLC). Antioxidant potency was determined by use of 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and total antioxidant capacity (TAC) assays. Antibacterial activity was assessed against gram-positive and gram-negative bacteria by use of disc diffusion and microdilution assays. Chromatographic analysis by HPLC showed four compounds in the polyphenol-rich fraction including 1-O-Caffeoyl glucose, Luteolin-7-diglucuronide, Apigenin-O-pentoside, and Quercetin-3-O-glucuronide. Polyphenol-rich fraction exhibited important antioxidant activity as assessed by DPPH and FRAP assays, with IC50 and EC50 values of 14.27 ± 0.43 and 39.48 ± 0.81 µg/mL, respectively, while butylated hydroxytoluene (BHT) and Quercetin exhibited IC50 values of 28.92 ± 0.24 and 22.48 ± 0.54 µg/mL. Results of TAC showed that the polyphenol-rich fraction scored 781.74 ± 2.83 µg AAE/mg. Polyphenol-rich fraction showed an important antibacterial effect vs gram-positive and gram-negative strains recording inhibition zone diameters varying from 19.5 to 29.2 mm, while antibiotics were almost ineffective toward all strains except for E. coli. It can be concluded that W. adpressa polyphenol-rich fraction possesses promising phenols with strong antioxidant and antibacterial properties, which may help fight pathogenic bacteria and free radicals.

Promising Antioxidant and Antimicrobial Potencies of Chemically-Profiled Extract from Withania aristata (Aiton) Pauquy against Clinically-Pathogenic Microbial Strains

Withania aristata (Aiton) Pauquy, a medicinal plant endemic to North African Sahara, is widely employed in traditional herbal pharmacotherapy. In the present study, the chemical composition, antioxidant, antibacterial, and antifungal potencies of extract from the roots of Withania aristata (Aiton) Pauquy (RWA) against drug-resistant microbes were investigated. Briefly, RWA was obtained by maceration with hydro-ethanol and its compounds were identified by use of high-performance liquid chromatography (HPLC). The antioxidant activity of RWA was determined by use of ferric-reducing antioxidant power (FRAP), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and total antioxidant capacity (TAC). The evaluation of the antimicrobial potential of RWA was performed against drug-resistant pathogenic microbial strains of clinical importance by use of the disc diffusion agar and microdilution assays. Seven compounds were identified in RWA according to HPLC analysis, including cichoric acid, caffeic acid, apigenin, epicatechin, luteolin, quercetin, and p-catechic acid. RWA had excellent antioxidant potency with calculated values of 14.0 ± 0.8 µg/mL (DPPH), 0.37 ± 0.08 mg/mL (FRAP), 760 ± 10 mg AAE/g (TAC), and 81.4% (β-carotene). RWA demonstrated good antibacterial potential against both Gram-negative and Gram-positive bacteria, with inhibition zone diameters ranging from 15.24 ± 1.31 to 19.51 ± 0.74 mm, while all antibiotics used as drug references were infective, except for Oxacillin against S. aureus. Results of the minimum inhibitory concentration (MIC) assay against bacteria showed that RWA had MIC values ranging from 2.13 to 4.83 mg/mL compared to drug references, which had values ranging from 0.031 ± 0.003 to 0.064 ± 0.009 mg/mL. Similarly, respectable antifungal potency was recorded against the fungal strains with inhibition zone diameters ranging from 25.65 ± 1.14 to 29.00 ± 1.51 mm compared to Fluconazole, used as a drug reference, which had values ranging from 31.69 ± 1.92 to 37.74 ± 1.34 mg/mL. Results of MIC assays against fungi showed that RWA had MIC values ranging from 2.84 ± 0.61 to 5.71 ± 0.54 mg/mL compared to drug references, which had values ranging from 2.52 ± 0.03 to 3.21 ± 0.04 mg/mL. According to these outcomes, RWA is considered a promising source of chemical compounds with potent biological properties that can be beneficial as natural antioxidants and formulate a valuable weapon in the fight against a broad spectrum of pathogenic microbes.

In Vitro Studies on the Antimicrobial and Antioxidant Activities of Total Polyphenol Content of Cynara humilis from Moulay Yacoub Area (Morocco)

In Morocco, Cynara humilis L. is used in traditional medicine. The objective of this research was to research the antioxidant and antimicrobial properties of hydroethanolic extracts from the C. humilis plant's leaves and roots. The content of polyphenols and flavonoids was evaluated using Folin-Ciocalteu's and aluminum chloride assays. Two techniques were used to evaluate antioxidant properties: antioxidant capacity in total (TAC) and 2,2-diphenyl-1-picrylhdrazyl (DPPH). In antimicrobial assays, five pathogenic microbial strains were studied including two Escherichia coli, one coagulase-negative Staphylococcus and Klebsiella pneumoniae, and one Candida albicans, by two techniques: agar disk diffusion and microdilution. Leaves had a greater content of flavonoids 27.07 mg QE/g of extract and the polyphenols 38.84 mg GAE/g of extract than root 24.39 mg QE/g of extract and 29.39 mg GAE/g of extract, respectively. The TAC test value of the 0.77 mg AAE/g extract in the leaf extract was found to be significantly greater than that of the 0.60 mg EAA/g extract in the root extract. The DPPH antioxidant assay IC₅₀ values of the root and leaf extract were 0.23 and 0.93 µg/mL, respectively. C. humilis extracts showed an antimicrobial effect against all tested strains, the inhibitory zone (DIZ) have values in the range between 12 and 15 mm. Moreover, the root extract showed the lowest minimum inhibitory concentration (MIC) against coagulase-negative Staphylococcus with an IC₅₀ value of 6.25 mg/mL. The higher content of flavonoids and polyphenols in the hydroethanolic extracts of C. humilis leaves and roots demonstrates that they have a significant antimicrobial and antioxidant effect, as found in this study.

Status analysis of herbal drug therapies in epilepsy: advancements in the use of medicinal plants with anti-inflammatory properties

BACKGROUND

Use of plants and plant products in health care has shown exponential increase in past two decades.

INTRODUCTION

In-spite of the availability of well-established pharmacotherapy for epilepsy, a large no of population still explores alternative treatments due to refractory seizures, adverse effects of drugs, chronic treatment, inaccessibility of standard therapies in rural areas and the social stigma attached to the disease. Various studies on medicinal plants showed the protective effect of herbals in animal models of epilepsy.

METHOD

In the present review, a status analysis of the traditional use of various medicinal plants in epilepsy with a special focus on plats having anti-inflammatory potential is recorded.

RESULT AND CONCLUSION

The shortcomings of research on medicinal plants which needs to be explored further in order to tackle the growing need of safer and effective drugs for epilepsy are discussed. Overall, there is a huge scope of herbal drugs in CNS disorders especially epilepsy, either as an adjunct by reducing the dose and thus side effects of standard anti-epileptic drugs or as standalone agent . Although, there is still an urgent need of well planned randomized controlled clinical trials to validate their efficacy and safety.