Chemical composition and antimicrobial activity of essential oils of Ocimum basilicum, Ocimum canum and Ocimum gratissimum in function of harvesting time

BACKGROUND: The aim of present the study was to investigate the chemical composition and the antimicrobial activity of essential oils of Ocimum basilicum, Ocimum canum and Ocimum gratissimum from Benin as affected by harvesting time. The chemical composition of hydrodistillated essential oils were analyzed by GC-FID (gas chromatography – flame ionization detector) and GC-MS (gas chromatography-mass spectrometry). Disc diffusion and broth microdilution assays were used to evaluate the antibacterial activity of essential oils against two foodborne pathogens. RESULTS: Based on the composition analysis, major components were as follows: estragol (43.0 -44.7 %) and linalool (24.6 -29.8 %) in O. basilicum oils; carvacrol (12.0 -30.8 %) and p-cymene (19.5 -26.2 %) in O. canum oils; thymol (28.3 -37.7 %) and γ-terpinene (12.5 -19.3 %) in O. gratissimum oils. The tested oils and their components exhibited notable antimicrobial activities against Listeria monocytogenes and Salmonella typhimurium. The O. canum and O. gratissimum oils collected at 7h and 19h showed significant higher activities against L. monocytogenes and S. typhimurium (MICs and MBCs 0.34 – 2.5 µL/mL) (p < 0.05), whereas O. basilicum showed lower activity (MICs and MBCs 2.0 – 8.0 µL/mL) at any daytime of harvest, the weakest being at 19h (MIC and MBC 12.0 – 32.0 µL/mL). CONCLUSION: The daytime of harvest can influence the composition of oils and their activities on bacteria

Commune agroecosystem analysis to support decision making for water allocation for fisheries and agriculture in the Tonle Sap wetland system

The Project on Commune Agroecosystem Analysis to Support Decision Making for Water Allocation for Fisheries and Agriculture in the Tonle Sap Wetland System was undertaken with the aim of improving fisheries considerations in the Commune Agroecosystem Analysis (CAEA) process undertaken in Cambodia, to facilitate better planning at the commune level. Under this project a number of changes were made to the CAEA tools and process and pilot tested in an adaptive, iterative manner in four communes – two that had conducted a CAEA previously and two that had not. Results and analyses indicated that the project had significantly strengthened the manner in which livelihoods, water resources and fisheries are now addressed by CAEA. The revised CAEA guidance manual has also shown potential for having wider uptake, and a number of tools have been used by several other projects within Cambodia

The antifungal plant defensin AhPDF1.1b is a beneficial factor involved in adaptive response to zinc overload when it is expressed in yeast cells

Antimicrobial peptides represent an expanding family of peptides involved in innate immunity of many living organisms. They show an amazing diversity in their sequence, structure, and mechanism of action. Among them, plant defensins are renowned for their antifungal activity but various side activities have also been described. Usually, a new biological role is reported along with the discovery of a new defensin and it is thus not clear if this multifunctionality exists at the family level or at the peptide level. We previously showed that the plant defensin AhPDF1.1b exhibits an unexpected role by conferring zinc tolerance to yeast and plant cells. In this paper, we further explored this activity using different yeast genetic backgrounds: especially the zrc1 mutant and an UPRE-GFP reporter yeast strain. We showed that AhPDF1.1b interferes with adaptive cell response in the endoplasmic reticulum to confer cellular zinc tolerance. We thus highlighted that, depending on its cellular localization, AhPDF1.1b exerts quite separate activities: when it is applied exogenously, it is a toxin against fungal and also root cells, but when it is expressed in yeast cells, it is a peptide that modulates the cellular adaptive response to zinc overload

South African Menopause Society revised consensus position statement on menopausal hormone therapy

The South African Menopause Society (SAMS) consensus position statement on menopausal hormone therapy (HT) 2014 is a revision of the SAMS Council consensus statement on menopausal HT published in the SAMJ in May 2007. Information presented in the previous statement has been re-evaluated and new evidence has been incorporated. While the recommendations pertaining to HT remain similar to those in the previous statement, the 2014 revision includes a wider range of clinical benefits for HT, the inclusion of non-hormonal alternatives such as selective serotonin reuptake inhibitors and serotonin noradrenaline reuptake inhibitors for the management of vasomotor symptoms, and an appraisal of bioidentical hormones and complementary medicines used for treatment of menopausal symptoms. New preparations that are likely to be more commonly used in the future are also mentioned. The revised statement emphasises that commencing HT during the 'therapeutic window of opportunity' maximises the benefit-to-risk profile of therapy in symptomatic menopausal women

Engineering Synthetic Microbial Communities through a Selective Biofilm Cultivation Device for the Production of Fermented Beverages

Production of Cambodian rice wine involves complex microbial consortia. Indeed, previous studies focused on traditional microbial starters used for this product revealed that three microbial strains with complementary metabolic activities are required for an e ective fermentation, i.e., filamentous fungi (Rhizopus oryzae), yeast (Saccharomyces cerevisiae), and lactic acid bacteria (Lactobacillus plantarum). Modulating the ratio between these three key players led to significant di erences, not only in terms of ethanol and organic acid production, but also on the profile of volatile compounds, in comparison with natural communities. However, we observed that using an equal ratio of spores/cells of the three microbial strains during inoculation led to flavor profile and ethanol yield close to that obtained through the use of natural communities. Compartmentalization of metabolic tasks through the use of a biofilm cultivation device allows further improvement of the whole fermentation process, notably by increasing the amount of key components of the aroma profile of the fermented beverage (i.e., mainly phenylethyl alcohol, isobutyl alcohol, isoamyl alcohol, and 2-methyl-butanol) and reducing the amount of o -flavor compounds. This study is a step forward in our understanding of interkingdom microbial interactions with strong application potential in food biotechnology

Fortified interpenetrating polymers – bacteria resistant coatings for medical devices

Infections arising from contaminated medical devices are a serious global issue, contributing to antibiotic resistance and imposing significant strain on healthcare systems. Since the majority of medical device-associated infections are biofilm related, efforts are being made to generate either bacteria-repellent or antibacterial coatings aimed at preventing bacterial colonisation. Here, we utilise a nanocapsule mediated slow release of a natural antimicrobial to improve the performance of a bacteria repellent polymer coating. Poly(lauryl acrylate) nanocapsules containing eugenol (4-allyl-2-methoxyphenol) were prepared and entrapped within a interpenetrating network designed to repel bacteria. When coated on a catheter and an endotracheal tube, this hemocompatible system allowed slow-release of eugenol, resulting in notable reduction in surface-bound Klebsiella pneumoniae and methicillin resistant Staphylococcus aureus