Oxidative stress plays a significant role in the pathogenesis of metabolic syndrome including diabetes mellitus (DM). The inhibition of alpha-amylase is an important therapeutic target in the regulation of postprandial increase of blood glucose in diabetic patients. The present study investigated the alpha-amylase inhibitory and antioxidant potential of selected herbal drugs used in the treatment of DM by the traditional healers in Isiala Mbano and Ikwuano regions of southeastern Nigeria. Antioxidant activity was evaluated in terms of free radical scavenging, reducing power, and total phenolic (TPC) and flavonoid content (TFC) in consonance with the TLC profiling. The results showed that methanol crude extracts from Anacardium occidentale (AO) and Ceiba pentandra (CP) recorded higher TPC and TFC, potent free radical scavenging, and efficient reducing power (RP) as compared with other plant samples. All the plant extracts exhibited a relative alpha-amylase inhibition apart from Strophanthus hispidus (SH) extract with a negative effect. We discovered a mild to weak correlation between alpha-amylase inhibition or antioxidative capacity and the total phenol or flavonoid content. At least in part, the results obtained in this work support the traditional use of certain plant species in the treatment of patients with DM.

No abstract

Background: The continuous search for new lead compounds of therapeutic importance has become necessary in the face of treatment failures and multidrug resistance plaguing the world. While many plants and higher fungi are sources of bioactive compounds yet to be fully harnessed, understanding the bioactive components in macrofungus could serve as a lead for investigating its biological activities and medicinal potentials. Materials and Methods: The bioactive compounds in the ethanolic extract of Lentinus Squarrosulus, an edible Nigerian macrofungus, were investigated by Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Results: There were nine bioactive compounds in this edible macrofungus. Of these compounds, 9,12-Octadecanoic acid ethyl ester (37.39%; RT:39.815) was the highest in quantity, followed by Hexadecanoic acid ethyl ester (14.49%; RT:36.550). Other fatty acids, their ethyl esters and other compounds identified included 2-Butenethioic acid,3-(ethylthio)-S-(1-methylethyl) ester (4.51%; RT:15.866), n-Hexadecanoic acid (4.74%; RT:36.034), 9,12-Octadecadienoic acid (Z,Z)- (11.88%; RT:39.429), 9,17-Octadecadienal,(Z)- (5.01%; RT:39.500), ethyl oleate (5.27%; RT:39.898), 3a,6-Methano-3aH-indene,2,3,6,7 tetrahydro (4.04%; RT:48.379), and 9,12-Octadecadienoic acid (Z,Z)-,2 hydroxy-1-(hydroxymethyl) ethyl ester (12.68%; RT:48.682). Some of these compounds have antimicrobial, antioxidant, hepatoprotective, hypocholesterolemic as well as cancer preventive activities amongst others. Conclusion: This study showed the bioactive components of therapeutic potentials in L. squarrosulus while creating a platform for screening, isolating and identifying many bioactive components which may be useful in the treatment of the various ailments, disorders and diseases in the nearest future.

Medicinal plants used for wound healing and skin diseases are the key to unlocking the doors to combating problematic skin diseases as resistance of pathogens to pharmaceuticals and allopathic management continues to increase. The study aimed at investigating the antimicrobial efficacies, phenolic content, and cytotoxicity effects of 11 medicinal plant extracts commonly used for treating skin conditions and wound healing in traditional medicine within KwaZulu-Natal. Eleven plant species were separated into different plant parts (bulbs, roots, leaves) and extracted with different solvents. The extracts were assessed for antimicrobial activity against six Gram-positive and seven Gram-negative bacterial strains and four fungi commonly associated with skin conditions using disc diffusion and microdilution techniques. The aqueous methanolic extracts were screened for phenolic content while cytotoxicity tests were performed on all extracts using the brine shrimp lethality and tetrazolium–based colorimetric (MTT) assays. Extracts from Aloe ferox, A. arborescens, and Hypericum aethiopicum were the most active against almost all of the tested bacterial and fungal strains. All plant species exhibited some degree of antimicrobial activity. Total phenolic levels, flavonoids and tannins were also higher for A. ferox, followed by A. arborescens and H. aethiopicum, respectively. The cytotoxicity results of all plant extracts were in the range of 90–100% survival after 24 h in the brine shrimp assay. Extracts considered lethal would demonstrate >50% shrimp death. The MTT cytotoxicity test yielded LC50 values of >1 mg/mL on all extracts indicating that they are not cytotoxic. The observed antimicrobial efficacy demonstrated by some plant species and the general lack of cytotoxic effects on all the tested extracts presents some promising and beneficial aspects of these medicinal plant extracts in the treatment of skin diseases and wound healing. The two Aloe species and H. aethiopicum were among the best extracts that exhibited consistently good antimicrobial activity and warrants further investigations and possible isolation of bioactive principles.

Background. This study was aimed at evaluating the antibacterial activity of the acetone extract of A. mearnsii and its interactions with antibiotics against some resistant bacterial strains. Methods. The antibacterial susceptibility testing was determined by agar diffusion and macrobroth dilution methods while the checkerboard method was used for the determination of synergy between the antibiotics and the extract. Results. The results showed that the susceptibility of the different bacterial isolates was concentration dependent for the extract and the different antibiotics. With the exception of S. marcescens, the inhibition zones of the extract produced by 20 mg/mL ranged between 18 and 32 mm. While metronidazole did not inhibit any of the bacterial isolates, all the antibiotics and their combinations, except for ciprofloxacin and its combination, did not inhibit Enterococcus faecalis. The antibacterial combinations were more of being antagonistic than of being synergistic in the agar diffusion assay. From the macrobroth dilution, the extract and the antibiotics exerted a varied degree of inhibitory effect on the test organisms. The MIC values of the acetone extract which are in mg/mL are lower than those of the different antibiotics which are in μg/mL. From the checkerboard assay, the antibacterial combinations showed varied degrees of interactions including synergism, additive, indifference, and antagonism interactions. While antagonistic and additive interactions were 14.44%, indifference interaction was 22.22% and synergistic interaction was 37.78% of the antibacterial combinations against the test isolates. While the additivity/indifference interactions indicated no interactions, the antagonistic interaction may be considered as a negative interaction that could result in toxicity and suboptimal bioactivity. Conclusion. The synergistic effects of the herbal-drug combinations may be harnessed for the discovery and development of more rational evidence-based drug combinations with optimized efficiency in the prevention of multidrug resistance and therapy of multifactorial diseases.

The present study assessed the antibacterial, cytotoxicity and antioxidative capacity of hydroalcoholic extract from the whole parts of Artemisia vulgaris (AV) using various in vitro assay models. Lipid Peroxidation (LPO), Protein Glycation (PG), Xanthine Oxidases (XO) and the stable 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) radical scavenging assays were used to evaluate the antioxidative capacity of AV extract. The Total Phenolic Content (TPC) was estimated based on Folic Ciocalteau reagent whilst, the phenolic compounds were characterized by HPLC-DAD. Here, the cytotoxicity nature of AV extract was evaluated using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) reagent on HepG2 hepatocarcinomal cells. Furthermore, the antibacterial potential was determined by using agar dilution method against our panel of bacterial strains. A mild antibacterial activity was exhibited against P. vulgaris ATCC 6830, E. faecalis ATCC 29212, S. mercescens ATCC 9986, S. aureus OK1 and OK3 having MIC value of 0.4 mg mLG 1 but less active towards other test bacteria. Similarly, the AV extract demonstrated a moderate inhibition of DPPH* (IC 50 : 0.976 µg mLG 1), LPO (IC 50 : 360 µg mLG 1), XO (IC 50 : 112.51 µg mLG 1) and PG (IC 50 : 968.4 µg mLG 1). The TPC was found to be 28.04±0.05 mg GAE gG 1 , which corresponds to the HPLC fingerprint. The AV extract exhibited non-toxic effect towards mammalian cells having an IC 50 value of 246.32±5.21 µg mLG 1. The data showed that Artemisia vulgaris had a mild antibacterial and antioxidative capacity despite its low phenolic composition and at least in part support its medicinal uses in folklore medicinal system.

No abstract

Rosa canina (RC, the Dog Rose) is used in European folk medicine for the treatment of various human ailments. The crude methanol extract of this botanical was tested against multidrug-resistant (MDR) bacterial strains including methicillin-resistant Staphylococcus aureus SA1199B, EMRSA-16 and XU212 harbouring NorA, PBP2a and TetK resistance mechanisms, respectively, as well as S. aureus ATCC25923, a standard antimicrobialsusceptible laboratory strain. Inhibition of the conjugal transfer of plasmids PKM101 and TP114 by the RC extract was also evaluated. The RC extract demonstrated a mild to poor antibacterial activity against the panel of bacteria having MIC values ranging from 256 to >512 mg/L, but strongly potentiated tetracycline activity (64-fold) against XU212, a tetracycline-effluxing and resistant strain. Furthermore, the extract showed moderate capacity to inhibit the conjugal transfer of TP114 and PKM101; transfer frequencies were between 40% and 45%. Cytotoxicity analysis of the RC extract against HepG2 cells line showed the IC50 >500µg/mL and thus was considered non-toxic toward human cells. Phytochemical characterisation of the extracts was performed by the assessment of total phenolic content (RC: 60.86 mg TAE/g) and by HPLC fingerprint determination. The results from this study provide new mechanistic evidence justifying, at least in part, the traditional use of this extract. However, the inhibition of bacterial plasmid conjugation opens the possibility of combination therapies to overcome antibiotic-resistance.