HPLC/ESI-MS Characterization of Phenolic Compounds from Cnicus benedictus L. Roots: A Study of Antioxidant, Antibacterial, Anti-Inflammatory, and Anti-Alzheimer's Activity.

The phenolic composition of Cnicus benedictus roots from four Algerian regions was investigated. Extractions were performed in both hydro-methanolic (30 : 70, v/v) and hydro-ethanolic (30 : 70, v/v) solvents. Their efficiency was determined in terms of the qualitative and quantitative composition in phenolic compounds by HPLC-LC/MS of the different extracts isolated from C. Benedictus roots. Cnicus benedictus roots extract have been characterized by high content of phenolic compounds, where the trans chalcone, 2,3-dihydro flavone, 3-hydroxy flavone and cinnamic acid constitute the major components, in addition to fourteen minor acidic compounds and flavonoids as rutin. The hydro-methanolic extract was the richest in phenolic compounds yield from C benedictus. On the other hand, hydro methanolic (30 : 70, v/v) and hydro ethanolic (30 : 70, v/v) extracts exhibited a high anti-inflammatory activity by in vitro 5-lipoxygenase inhibitory activity (IC50 : 6.05±94.16 µg/mL) as well as by in silico docking according two methods. Likewise, anti-Alzheimer activity of extracts was confirmed by this last technique taking into account the major compounds identified. Antibacterial tests revealed interesting results compared to amoxicillin for the different regions studied with a high content in trans chalcone and 3-hydroxy Flavone.

A new method of extracting polyphenols from honey using a biosorbent compared to the commercial resin amberlite XAD2.

A new extraction method of polyphenols from honey using a biodegradable resin was developed and compared with the common commercial resin amberlite XAD2. For this purpose, three honey samples of Algerian origin were selected for the different physicochemical and biochemical parameters study. After extraction of the target compounds by both resins, the polyphenol content was determined, the antioxidant activity was tested, and liquid chromatography-mass spectrometry analyses were performed for identification and quantification. The results showed that physicochemical and biochemical parameters meet the norms of the International Honey Commission, and the H1 sample seemed to be of high quality. The optimal conditions of extraction by biodegradable resin were a pH of 3, an adsorption dose of 40 g/L, a contact time of 50 min, an extraction temperature of 60°C, and no stirring. The regeneration and reuse number of both resins was three cycles. The polyphenol contents demonstrated a higher extraction efficiency of biosorbent than of XAD2, especially in H1. Liquid chromatography-mass spectrometry analyses allowed for the identification and quantification of 15 compounds in the different honey samples extracted using both resins and the most abundant compound was 3,4,5-trimethoxybenzoic acid. In addition, the biosorbent extracts showed stronger antioxidant activities than the XAD2 extracts.

Headspace Solid Phase Microextraction Coupled to GC/MS for the Analysis of Volatiles of Honeys from Arid and Mediterranean Areas of Algeria.

The volatile composition of seven honey samples collected from various regions of Algeria and feeding on different plants have been determined. The Headspace Solid-Phase MicroExtraction (HS-SPME) coupled with Gas Chromatography-Mass Spectrometry (GC/MS) was used to achieve the purpose. In this work, different parameters of the HS-SPME analytical method were investigated in order to reach maximal sensitivity, and thus to obtain maximum information about the volatile profile of Algerian honey. These parameters include saline medium, HS extraction temperature, and the nature of the fiber used. The results showed a great diversity in the chemical composition, in total 124 compounds from different chemical classes were identified, including compounds found for the first time in honey. The Ascending Hierarchical Classification (AHC) demonstrated the importance of choosing SPME extraction conditions to find volatile compounds, which could be as specific markers of the floral or geographical origin of honey, the latter was optimized in the parameter PDMS-55 °C.

DFT study of the mechanisms of nonenzymatic DNA repair by phytophenolic antioxidants.

Reactive oxygen species (ROS) can oxidize and thus damage DNA. Exposure to high levels of ROS is therefore linked with the development of severe illnesses such as cancer, diabetes, and coronary heart disease. Effective treatments for these diseases are yet to be found, despite intensive research. However, it is known that the natural nonenzymatic repair of DNA damage using phytophenols occurs more rapidly than the corresponding enzymatic repair process. Carvacrol, thymol, thymohydroquinone, and p-cymene-2,3-diol are strong natural antioxidant phytophenols that are found in medicinal plants. Their antioxidant activities, which involve reacting with and eliminating ROS before they reach and damage DNA, were studied in this work. Homolytic and heterolytic antioxidant mechanisms that allow these phytophenol antioxidants to eliminate the ROS .OH and .O2- in both vacuum and water (physiological environment) were investigated using density functional theory (DFT). The results showed that the homolytic mechanism is preferred in vacuum, whereas the heterolytic mechanisms are more probable in polar environments. In addition, the electronic properties of these phytophenols were studied and correlated with their antioxidant activities. It appears that these phytophenols can be used as antioxidants in vitro and in vivo to protect living systems from dangerous ROS. Graphical abstract Antioxidant reaction of carvacrol with OH. and .O-2 radicals.