Contemporary civilization is facing more than thousands of disorders accompanied with free radicals. Antioxidants from edible and non-edible mushrooms are gaining importance to fight these disorders. The current investigation was intended to evaluate antioxidant and cytotoxic effects of a well known edible oyster mushroom, Pleurotus highking (P. highking). Antioxidant activity of the methanolic crude extracts of Pleurotus highking was done on total phenolic contents and reducing power activity. Cytotoxic study was performed by brine shrimp lethality bioassay with the larvae of Artemia salina. Total phenolic contents of the extracts was found to be 20.100±0.049 mg of catechin/gm of dried extract whereas the reducing power activity of the extracts was found to be dose depended and was 0.062, 0.091, 0.146, 0.283 and 0.618 at concentration of 6.25 µg/ml, 12.5 µg/ml, 25 µg/ml, 50 µg/ml and 100 µg/ml of the extract respectively. The cytotoxic potentiality of the extracts was found as dose and time depended manner. 100% mortality rate of the brine shrimp larvae was found at a concentration of 480 µg/ml and more. The LC50 of the extracts was found to be 7.94 µg/ml. The present study suggests that the P. highking possesses remarkable antioxidant and cytotoxic property.
Introduction: Recently there has been a great deal of interest in the health benefits of phytochemicals, particularly prenylated and allylated flavonoids. Chalcones (1, 3-diaryl-2-propen-1-ones) and their derivatives are important intermediates of the flavonoid synthetic pathway.
Aims: To synthesis chalcones, and investigate their antimicrobial properties by determining their diameters of inhibition; minimum inhibitory concentration (MIC); and their minimum bactericidal and fungicidal concentrations (MBC), using the Kirby-Bauer diffusion and microdilution method.
Study Design: Experimental analytical study.
Place and Duration of Study: The study was done in the Laboratory of Organic Chemistry of the Faculty of Science, University of Yaounde1 and the Bacteriology Laboratory of the Yaoundé University Teaching Hospital.
The study was done in a period of 6 months, from the 15th of December 2014 to the 22nd of May 2015.
Methodology: The chalcones (3a-c) were synthesized by the Claisen Schmidt condensation reaction of vanillin (1) with different acetophenone derivatives (2a-c).
Results: The structures of the compounds were confirmed by spectral data (1H and 13C Nuclear Magnetic Resonance). Compound 3c is a new compound while the compounds 3a and 3b have already been reported [26,27]. The synthesized compounds were tested for their antimicrobial activities (agar disc-diffusion and microdilution methods). All the synthesized chalcones were active against the test microbes: The most potent compound was 3c; bactericidal on 50% of strains with a MIC between 62.5 and 250 μg/mL, the most sensitive strains being S. aureus and C. albicans, and the least sensitive being E. faecalis.
Conclusion: Synthesized chalcones showed antimicrobial properties and are very promising as lead compounds for drug development.
We demonstrated that all the test microbes were susceptible to the 3 synthesized chalcones at low concentrations. The halogenated chalcone (3c) was the most potent of the synthesized chalcones against reference strains of Gram negative and Gram positive bacteria, and the clinical strain of C. albicans. Therefore the presence of halogens in chalcones increases their microbial susceptibility.
Acacia mearnsii is characterized as a tree with dark green leaves and grow on any types of soil. Its bipinnate leaves with individual leaflets that are used in folk medicine in wound healing, antioxidant, anti-inflammatory and antiviral. Phytochemical tests demonstrated the presence of saponins, flavonoids and tannins. The haemolytic activity evaluation of dry crude buthanolic leaves extract of A. mearnsii confirming the presence of saponins as a chemical marker of this species presenting a low haemolytic content in comparison with Tribullus terrestres, herbal reference product.
This study was designed to determine the acute and subacute toxicity of non-ionic surfactant, sorbitan monostearate (Span 60) vesicles in a Sprague Dawley rat model. The primary aim was to investigate the acute toxicity of Span 60 niosomes after single intraperitoneal (IP) as well as once daily bolus dose for 5 days. Niosomes were prepared by the thin-film hydration method and subjected to ultracentrifugation to produce a final concentration of 30 mg of span 60 in 1 ml of niosome suspension. Acute toxicity study was performed following OECD test guideline 423 with modifications. Animals were divided into four groups, two control groups and two treatment groups. Group 1 animals were administered single 600 mg/kg IP bolus dose, whilst group 2 animals received 120 mg/kg/day IP for 5 days. The controls for each treatment group was administered an equivalent volume of phosphate buffered saline (PBS). Their body weight, food intake, water intake, fecal mass and urine output were measured daily. All clinical signs, time of onset, duration, and reversibility of toxicity or mortality were documented. Gross necropsies were performed on all animals terminated at 14 days post injection. There was no treatment related deaths and no toxic signs were observed in the two treatment groups. There was an initial decrease in food intake and, hence, body weight with IP niosome injection. However, weight loss was less than 10 percent in both groups of animals. All other parameters measured showed no statistical significance between niosome treated group and placebo. Necropsy performed at day 14 showed no signs of local reaction and there was no discernible effect on major organs. Results indicated that the LD50 of IP injected Span 60 was greater than 600 mg/kg. Therefore, Span 60-based niosomes appear to be non-toxic at the tested doses and experimental conditions and may not contribute to the potential toxicity of drug-loaded niosomes of this surfactant.
The Mucoadhesive drug delivery system has occupied an important place in the field of pharmaceutical research. Mucoadhesive tablets prolong the residence time of the drug at the site of application and provide extended therapeutic effect. Mucoadhesive tablets have been prepared for various sites thus offering localization as swell as systemic control of drug release. The present study focuses on the concept of formulation of fluconazole as a mucoadhesive vaginal tablet, for improving the sustained release of drug and localized action of the drug. Different polymers, such as Hydoxypropylmethylcellulose M 15, Carbopol71G-NFand Guar Gum were used with different concentrations in order to get the desired sustained release profile over a period of more than12 hrs. The tablets were prepared by direct compression method. All the formulations were evaluated for crushing strength, friability, swelling behavior, adhesion time, drug content and in vitro drug release profile. All the formulation tested showed good physical and adhesive properties. It was found that the controlled release rate of the formulation increases with increasing polymer concentration. Kinetican modeling of release data supports an anomalous non-fickian release behavior. The antimycotic activity of selected formulations containing fluconazole (100 mg) was determined using an agar diffusion technique. Formulations tested showed activity against C. albicans.
The thermostability of aqueous extracts of Tetrapleura tetraptera pods (AETTP) and its in-vitro antibacterial activities on multidrug-resistant (MDR) clinical isolates were carried out using standard bacteriological and disc diffusion techniques. Eleven genera comprising Staphylococcus, Escherichia, Proteus, Streptococcus, Klebsiella, Pseudomonas, Citrobacter, Enterobacter, Salmonella, Enterococcus and Serratia were obtained from the clinical samples. The results showed that between 19 /35 (54.3%) and 30 /35 (85.7%) faecal isolates were sensitive to all the antibiotics, while Streptococcus pyogenes isolated from wound samples were highly sensitive to gentamycin, nalidixic acid, ciprofloxacin and ofloxacin. Less than 31 (32.6%) of the bacteria showed resistance to multiple antibiotics with 19 (20%) showing resistance to ≥ 4 antibiotics. The phytochemical screening and qualitative estimations of AETTP revealed the presence of alkaloids, anthraquinones, tannins, flavonoids, steroids, reducing sugar, saponins, cardiac glycoside and protein in varied concentrations. The MDR bacteria were markedly inhibited by 40 mgml-1 and 80 mgml-1 AETTP kept at 26ºC with inhibitory zones ranging from 10.3 ± 1.0 mm to 17.4 ± 2.2 mm, while decrease in the inhibitory zones were observed when AETTP boiled to 50ºC, 75ºC and 100ºC were used. The AETTP boiled to 1000C immensely lost its antibacterial activities, as ≥ 42.1% of the bacteria were resistant to AETTP. The MIC values of AETTP ranged from 5 to 40 mgml-1, while the MBC values ranged from 20 to 160 mgml-1. The highest MIC of 40 mgml-1 and MBC of 160 mgml-1 were obtained when the AETTP was tested against S. aureus (SAU5) and Salmonella spp (SSS2). Although, AETTP has antibacterial activities on both MDR Gram positive and Gram negative bacteria, could be used to develop a novel and broad-spectrum antibiotic for the treatment of MDR bacterial infections, its antibacterial activities could be markedly lost by high temperature.
Several pathogenic bacteria are developing antibiotic resistance. Recovery from multidrug resistant (MDR) infections is a problematic issue and requires a multiple treatment with broad-spectrum antibiotics which are less effective, more toxic and more expensive. Silver nanoparticles (AgNPs) are attracting much interest because of their potent antibacterial and anti-biofilm activities. These nanoparticles are extensively synthesized and used as an effective broad spectrum antibacterial agent against Gram negative and Gram positive bacteria including antibiotic resistant bacteria. Silver attacks multiple targets in the microorganism therefore decreases its ability to develop resistance. Effect of coating on AgNPs stability, toxicity on the microbial host and their antimicrobial activity was discussed. The incorporation of AgNPs into hydrogels magnifies the antibacterial activity according to their characteristics, hydrogels work as an efficient stabilizer of AgNPs and control the release of AgNPs. In the present review, the silver nanoparticles-hydrogel and their components as well as their antibacterial activities and wound healing efficacies are reviewed and discussed on the bases of component variabilities and characteristics. Different factors and topics are considered since there are challenges and problematic issues need to be faced and solved for development of new ideal antibacterial formulation.