New Trends in Biosurfactants: From Renewable Origin to Green Enhanced Oil Recovery Applications.

Enhanced oil recovery (EOR) processes are technologies used in the oil and gas industry to maximize the extraction of residual oil from reservoirs after primary and secondary recovery methods have been carried out. The injection into the reservoir of surface-active substances capable of reducing the surface tension between oil and the rock surface should favor its extraction with significant economic repercussions. However, the most commonly used surfactants in EOR are derived from petroleum, and their use can have negative environmental impacts, such as toxicity and persistence in the environment. Biosurfactants on the other hand, are derived from renewable resources and are biodegradable, making them potentially more sustainable and environmentally friendly. The present review intends to offer an updated overview of the most significant results available in scientific literature on the potential application of biosurfactants in the context of EOR processes. Aspects such as production strategies, techniques for characterizing the mechanisms of action and the pros and cons of the application of biosurfactants as a principal method for EOR will be illustrated and discussed in detail. Optimized concepts such as the HLD in biosurfactant choice and design for EOR are also discussed. The scientific findings that are illustrated and reviewed in this paper show why general emphasis needs to be placed on the development and adoption of biosurfactants in EOR as a substantial contribution to a more sustainable and environmentally friendly oil and gas industry.

NMR Spectroscopy Applied to the Metabolic Analysis of Natural Extracts of Cannabis sativa.

Cannabis sativa is a herbaceous multiple-use species commonly employed to produce fiber, oil, and medicine. It is now becoming popular for the high nutritional properties of its seed oil and for the pharmacological activity of its cannabinoid fraction in inflorescences. The present study aims to apply nuclear magnetic resonance (NMR) spectroscopy to provide useful qualitative and quantitative information on the chemical composition of seed and flower Cannabis extracts obtained by ultra-sound-assisted extraction, and to evaluate NMR as an alternative to the official procedure for the quantification of cannabinoids. The estimation of the optimal ω-6/ω-3 ratio from the 1H NMR spectrum for the seed extracts of the Futura 75 variety and the quantitative results from the 1H and 13C NMR spectra for the inflorescence extracts of the Tiborszallasi and Kompolti varieties demonstrate that NMR technology represents a good alternative to classical chromatography, supplying sufficiently precise, sensitive, rapid, and informative data without any sample pre-treatment. In addition, different extraction procedures were tested and evaluated to compare the elaboration of spectral data with the principal component analysis (PCA) statistical method and the quantitative NMR results: the extracts obtained with higher polarity solvents (acetone or ethanol) were poor in psychotropic agents (THC < LOD) but had an appreciable percentage of both cannabinoids and triacylgliceroles (TAGs). These bioactive-rich extracts could be used in the food and pharmaceutical industries, opening new pathways for the production of functional foods and supplements.

Different BRIJ97 colloid systems as potential enhancers of acyclovir skin permeation and depot.

The low efficacy of Acyclovir topical therapy is due to its physicochemical properties that limit the permeation across the stratum corneum. The goal of this research was to evaluate the ability of biodegradable surfactant, Brij97, to self-assembly in different types of colloid systems which can improve the Acyclovir permeation and accumulation at the target site (the basal epidermis). New Acyclovir formulation based on Brij97 have been analyzed in order to investigate the effect of drug encapsulation on the structure. After that, the in vitro percutaneous permeation of Acyclovir has been compared with that one of the commercial specialty Zovirax® 5%. To estimate the potential of the new formulations proposed as topical delivery, it has been essential to quantify the Acyclovir in the skin layers. The results confirmed that the self-assembly of the surfactant in different nanosized structures improved the amount of permeated Acyclovir and the formation of intracutaneous drug reservoir. Furthermore, the different lipophilicity and structural organization of carriers based on Brij97 showed different influence on the promotion of permeation. The experimental data suggest that the designed carriers could be a valid alternative to improve the efficacy of the current antiviral therapy.