Characterization and application of Croton blanchetianus Baill extract for lamb ribs preservation

Antibiofilm Effects of Oleuropein against Staphylococcus aureus: An In Vitro Study

Staphylococcus aureus has posed a huge threat to human health and the economy. Oleuropein has antibacterial activities against various microorganisms but research on its effect on the S. aureus biofilm is limited. This research aimed to estimate the antibiofilm activities of oleuropein against S. aureus. The results suggest that the minimum inhibitory concentration of oleuropein against S. aureus ATCC 25923 was 3 mg/mL. The biomass of biofilms formed on the microplates and coverslips and the viability of bacteria were significantly reduced after the treatment with oleuropein. The scanning electron microscopy observation results indicated that the stacking thickness and density of the biofilm decreased when S. aureus was exposed to oleuropein. It had a bactericidal effect on biofilm bacteria and removed polysaccharides and proteins from mature biofilms. The effects of oleuropein on the biofilm could be explained by a reduction in bacterial secretion of extracellular polymeric substances and a change in bacterial surface hydrophobicity. Based on the above findings, oleuropein has the potential to be used against food pollution caused by S. aureus biofilms.

Phytochemical profile analysis by LC-ESI-MSn and LC-HR-ESI-MS and validated HPLC method for quantification of rutin in herbal drug and products from leaves of Croton blanchetianus

Phytochemical analysis of Croton blanchetianus leaves was performed by. After that, a high performance liquid chromatography method was developed and validated for the determination of rutin in herbal drug and products of C. blanchetianus. The separation was achieved on a C18 column, and the mobile phase was composed of ultrapure water and methanol (acidified with trifluoroacetic acid) with a gradient of 0.8 ml/min. The method was validated following international guidelines. The chemical analysis revealed the presence of flavonoids. Among them rutin was used as the standard for validation. In the HPLC the presence of rutin was observed at 24.7 min. The method was robust, with no significant variations, and linear in the range evaluated with R2  > 0.99. Regarding the matrix effect, it was possible to prove the absence of interference of the constituents in the herbal drug. The precision was determined with a relative standard deviation of <1.34%. The recovery results were achieved between 89.29 and 101.21%. Furthermore, with partial validation, the method was proved to be suitable for the liquid extract, dry extract and effervescent granules. Therefore, this study demonstrated that the method is effective for the quality control analysis of C. blanchetianus leaves and products.

An overview of the natural antimicrobial alternatives for sheep meat preservation

Sheep meat is consumed and appreciated all over the world for its nutritional value and flavor. However, this meat is very perishable and easily subjected to the action of both spoilage and pathogenic microorganisms. For this reason, in combination with cold storage, effective preservation techniques are required. There is increasing interest in the application of natural antimicrobials, such as essential oils, extracts, spices, and by-products of the food industry. This review analyses the studies on natural antimicrobials in sheep meat and sheep meat products and gathers evidence about the encouraging results achieved on the reduction and/or elimination of spoilage and pathogenic microorganisms. The use of these natural antimicrobial alternatives might open up important perspectives for industrial application, considering that this specific meat is often traded over long distances. In fact, on the basis of scientific literature, natural antimicrobials can be considered a sustainable and affordable alternative to extend the shelf life of sheep meat and guarantee its safety, although many factors need to be further investigated, such as the sensory impact, potential toxicity, and economic aspects. For all these issues, investigated in some of the studies reviewed here, it is fundamental to obtain the antimicrobial effect with the minimum amount of effective substance to avoid sensory modifications, toxic effects, and unbearable costs. This study sets foundations for the possible direction of future studies, which will contribute to identify effective solutions for industrial applications of natural antimicrobials in the sheep meat industry.

Study on the Chemical Composition and the Biological Activities of Vitis vinifera Stem Extracts

Vitis vinifera (V. vinifera) is a herbaceous plant, cultivated worldwide and known for its biological benefits. The aim of this study is the investigation of the chemical composition as well as the determination of the biological potential of different grape stem extracts obtained by maceration and accelerated solvent extraction (ASE). The HPLC analysis of the tested extracts led to the identification of 28 compounds of which 17 were identified for the first time in grape plants, in addition to seven revealed in the stem part for the first time. Twenty-nine volatile molecules have been detected by GC-MS in the grape stem part; among them seven were identified for the first time in the grape plant. For the biological analysis, the ethyl acetate extract (EtOAc) obtained by maceration showed a significant potential regarding antioxidant activity (IC₅₀ = 42.5 µg/mL), anti-Alzheimer (IC₅₀ = 14.1 µg/mL), antidiabetic (IC₅₀ = 13.4 µg/mL), cytotoxic with HCT-116 (IC₅₀ = 12.5 µg/mL), and anti-inflammatory (IC₅₀ = 26.6 µg/mL) activities, as well as showing the highest polyphenol content (207.9 mg GAE/g DW).