Effect of ionizing radiation on antioxidant compounds present in cork wastewater

Quercus suber: A Promising Sustainable Raw Material for Cosmetic Application

There is a drive within the cosmetic industry towards the development of more sustainable products, supported by consumer awareness of the environmental footprint. The cosmetic industry is rising to meet consumer demand by following practices, such as the use of by-products from agro-industrial waste. Quercus suber is a tree prevalent in the Mediterranean basin. The extraction of cork is considered sustainable, as this process does not harm the tree, and the amount of cork produced increases with the number of extractions. Beyond this, the cork industry produces by-products that are used to sustain the industry itself, such as cork powder, which is reused for generating energy. Additionally, cork and cork by-products contain bioactive compounds mainly with antioxidant activity that can be of use to the cosmetic industry, such as for antiaging, anti-acne, anti-inflammatory, and depigmenting cosmetic products. We provide the reader with an overview of the putative cosmetic applications of cork and its by-products as well as of their bioactive compounds. It is noteworthy that only a few cork-based cosmetic products have reached the market, namely antiaging and exfoliant products. Clearly, the use of cork upcycled cosmetic ingredients will evolve in the future considering the wide array of biological activities already reported.

The Green Method in Water Management: Electron Beam Treatment

During the prebiotic era, radiolytic transformations in the oceans played a key role in purifying water from toxic impurities and, thus, played a role in the formation of the aquatic environment of our planet, making it suitable for the emergence of life. Today, the planet again faces the challenge of how to provide people with clean water. Therefore, it is reasonable to look back at past historical stages and again consider the possibility of neutralizing pollutants in water by means of radiolysis, which has already been tested by time. Modern radiolytic treatments can be much faster and safer thanks to the advent of powerful electron accelerators and high-rate electron beam treatment (ELT) of water and wastewater. Radiolytic treatment of water using accelerated electrons corresponds to the essence of advanced oxidative technologies and green chemistry. The ELT of water instantly generates a high concentration of short-lived radicals that can quickly neutralize and decompose chemical and bacterial pollutants. Due to the ability of accelerated electrons to penetrate into a substance, ELT provides the decomposition of both dissolved and suspended pollutants. The cleaning effect of ELT is due to the ability to inactivate toxic and chromophore functional groups, transform impurities into an easily removable form, damage the DNA of microorganisms and their spore forms, and increase the biodegradability of organic impurities. The use of ELT in water treatment provides significant savings in chemical reagents, thereby improving quality and reducing the number of cleaning steps. The compactness, high degree of automation of the equipment used, energy efficiency, high productivity, and excellent compatibility with traditional water treatment methods are important advantages of ELT. Unlike conventional chemicals, the excess radicals generated in the ELT process are converted back to water and hydrogen; thus, the chemical and corrosive activity of water does not increase. Equipping research institutes with electron accelerators, developing cheaper accelerators, and granting government support for pilot projects are key conditions for introducing ELT into water treatment practice.

Recovery of phenolic compounds from multi-component solution by a synthesized activated carbon using resorcinol and formaldehyde

The adsorption of four phenolic compounds (gallic acid, protocatechuic acid, vanillic acid and syringic acid) is investigated using a synthesized mesoporous carbon on both single and multi-component synthetic solutions. Some correlation of the adsorption capacity of the carbon and the nature of adsorbate could be made, except for gallic acid whose concentration decrease seems to be not exclusively due to adsorption but also to polymerization reaction. In the multi-component mixture, negative effects in the adsorption capacity are observed probably due to competition for the active centers of the adsorbent surface. In desorption studies, ethanol presents better performance than water and acetonitrile. Vanillic acid is the compound with the higher adsorption and interestingly it is then possible to desorb a relatively high amount of it from the adsorbent, which may represent a possibility for a selective recovery of vanillic acid. These results present a potential way to treat the wastewater from the cork industry.

Effects of gamma radiation on cork wastewater: Antioxidant activity and toxicity

A comprehensive assessment of the toxicity and antioxidant activity of cork boiling wastewater and the effects of gamma radiation on these parameters was performed. Antioxidant activity was evaluated using different methodologies as DPPH radical scavenging activity, reducing power and inhibition of β-carotene bleaching. The results have shown that gamma radiation can induce an increase on the antioxidant activity of cork boiling wastewater. Toxicity tests were performed to access the potential added value of the irradiated wastewaters and/or minimization of the impact for discharge in the environment. Two different methods for toxicity evaluation were followed, bacterial growth inhibition test and cytotoxicity assay, in order to predict the behavior of different cells (prokaryotic and eukaryotic) in the presence of cork wastewater. Non-treated cork boiling wastewater seemed to be non-toxic for prokaryotic cells (Pseudomonas fluorescens and Bacillus subtilis) but toxic for eukaryotic cells (A549 human cells and RAW264.7 mouse cells). The gamma radiation treatment at doses of 100 kGy appeared to increase the toxicity of cork compounds for all tested cells, which could be related to a toxic effect of radiolytic products of cork compounds in the wastewaters.