Phlorotannins are secondary metabolites produced mainly by brown seaweeds (Phaeophyceae) and belong to the class of polyphenolic compounds with diverse bioactivities. The key factors in the extraction of polyphenols are the selection of a suitable solvent, method of extraction and selection of optimal conditions. Ultrasonic-assisted extraction (UAE) is one of the advanced energy-saving methods suitable for the extraction of labile compounds. Methanol, acetone, ethanol and ethyl acetate are the most commonly used solvents for polyphenol extraction. As alternatives to toxic organic solvents, a new class of green solvents, natural deep eutectic solvents (NADES), has been proposed for the efficient extraction of a wide range of natural compounds including polyphenols. Several NADES were screened previously for the extraction of phlorotannins; however, the extraction conditions were not optimized and chemical profiling of NADES extract was not performed. The purpose of this work was to study the effect of selected extraction parameters on the phlorotannin content in NADES extract from Fucus vesiculosus, optimization of extraction conditions and chemical profiling of phlorotannins in the NADES extract. A fast and green NADES-UAE procedure was developed for the extraction of phlorotannins. Optimization was performed through an experimental design and showed that NADES (lactic acid:choline chloride; 3:1) provides a high yield (137.3 mg phloroglucinol equivalents per g dry weight of algae) of phlorotannins under the following extraction conditions: extraction time 23 min, 30.0% water concentration and 1:12 sample to solvent ratio. The antioxidant activity of the optimized NADES extract was equal to that of EtOH extract. In total, 32 phlorotannins have been identified (one trimer, two tetramers, six pentamers, four hexamers, six heptamers, six octamers and seven nonamers) in NADES extracts from arctic F. vesiculosus using the HPLC-HRMS and MS/MS technique. It was noted that all the above-mentioned phlorotannins were identified in both EtOH and NADES extracts. Our results suggest that NADES could be considered as an alternative to the conventional techniques for the effective extraction of phlorotannins from F. vesiculosus with high antioxidant potential.

Betulin is a natural triterpene, usually from birch bark, known for its potential wound-healing properties. Despite having a wide range of pharmacological targets, no studies have proposed betulin as a multitarget compound. Betulin has protective effects against cardiovascular and liver diseases, cancer, diabetes, oxidative stress, and inflammation. It reduces postprandial hyperglycemia by inhibiting α-amylase and α-glucosidase activity, combats tumor cells by inducing apoptosis and inhibiting metastatic proteins, and modulates chronic inflammation by blocking the expression of proinflammatory cytokines via modulation of the NFκB and MAPKs pathways. Given its potential to influence diverse biological networks with high target specificity, it can be hypothesized that betulin may eventually become a new lead for drug development because it can modify a variety of pharmacological targets. The summarized research revealed that the diverse beneficial effects of betulin in various diseases can be attributed, at least in part, to its multitarget anti-inflammatory activity. This review focuses on the natural sources, pharmacokinetics, pharmacological activity of betulin, and the multi-target effects of betulin on signaling pathways such as MAPK, NF-κB, and Nrf2, which are important regulators of the response to oxidative stress and inflammation in the body.

Diabetes remains a major health emergency in our entire world, affecting hundreds of millions of people worldwide. In conjunction with its much-dreaded complications (e.g., nephropathy, neuropathy, retinopathy, cardiovascular diseases, etc.) it substantially reduces the quality of life, increases mortality as well as economic burden among patients. Over the years, oxidative stress and inflammation have been highlighted as key players in the development and progression of diabetes and its associated complications. Much research has been devoted, as such, to the role of antioxidants in diabetes. Astaxanthin is a powerful antioxidant found mostly in marine organisms. Over the past years, several studies have demonstrated that astaxanthin could be useful in the treatment and management of diabetes. It has been shown to protect β-cells, neurons as well as several organs including the eyes, kidney, liver, etc. against oxidative injuries experienced during diabetes. Furthermore, it improves glucose and lipid metabolism along with cardiovascular health. Its beneficial effects are exerted through multiple actions on cellular functions. Considering these and the fact that foods and natural products with biological and pharmacological activities are of much interest in the 21st-century food and drug industry, astaxanthin has a bright prospect in the management of diabetes and its complications.

The chiral discrimination on interfaces functionalized by macrocyclic hosts, including cyclodextrins (CDs), chiral calix[n]arenes, pillar[n]arenes and cucurbit[n]uril.

The modification of chitosan represents a challenging task in obtaining biopolymeric materials with enhanced removal capacity for heavy metals. In the present work, the adsorption characteristics of chitosan modified with carboxyl groups (CTS-CAA) towards copper (II) and zinc (II) ions have been tested. The efficacy of the synthesis of CTS-CAA has been evaluated by studying various properties of the modified chitosan. Specifically, the functionalized chitosan has been characterized by using several techniques, including thermal analyses (differential scanning calorimetry and thermogravimetry), spectroscopies (FT-IR, XRD), elemental analysis, and scanning electron microscopy. The kinetics and the adsorption isotherms of CTS-CAA towards both Cu (II) and Zn (II) have been determined in the aqueous solvent under variable pH. The obtained results have been analyzed by using different adsorption models. In addition, the experiments have been conducted at variable temperatures to explore the thermodynamics of the adsorption process. The regeneration of CTS-CAA has been investigated by studying the desorption process using different eluents. This paper reports an efficient protocol to synthesize chitosan-based material perspective as regenerative adsorbents for heavy metals.