Structures, NMR Spectroscopic Features, and Cytotoxic Properties of Oligomeric Hellinoyl (m-GO-m-GOG)-Type Ellagitannins from the Galls of Tamarix aphylla

Phytochemical and pharmacological properties of the genus Tamarix: a comprehensive review

The genus Tamarix in the Tamaricaceae family consists of more than 100 species of halophyte plants worldwide that are mainly used to improve saline-alkali land and for coastal windbreaks, sand fixation, and afforestation in arid areas. A considerable number of species in this genus are also used as traditional medicines to treat various human diseases, especially in Asian and African countries. This review presents a comprehensive summary of 655 naturally occurring compounds derived from the genus Tamarix, categorized into flavonoids (18.0%), phenols (13.9%), tannins (9.3%), terpenoids (10.5%), essential oils (31.0%), and others (17.3%). The investigation revealed that the crude extracts and phytochemicals of this genus exhibited significant therapeutic potential, including anti-inflammatory, anti-Alzheimer, anticancer, antidiabetic, antibacterial, and antifungal activities. Six species of Tamarix have anticancer effects by causing cancer cell death, inducing autophagy, and stopping cell division. Seven species from the same genus have the potential for treating diabetes by inhibiting α-glycosidase activity, suppressing human islet amyloid polypeptide, regulating blood glucose levels, and modulating autophagy or inflammation. The focus on antibacterial and antidiabetic effects is due to the presence of volatile oil and flavonoid components. Extensive research has been conducted on the biological activity of 30 constituents, including 15 flavonoids, 5 phenols, 3 terpenoids, 1 tannin, and 6 others. Therefore, future research should thoroughly study the mechanisms of action of these and similar compounds. This is the most comprehensive review of the phytochemistry and pharmacological properties of Tamarix species, with a critical assessment of the current state of knowledge.

New Megastigmane and Polyphenolic Components of Henna Leaves and Their Tumor-Specific Cytotoxicity on Human Oral Squamous Carcinoma Cell Lines

Polyphenols have a variety of phenolic hydroxyl and carbonyl functionalities that enable them to scavenge many oxidants, thereby preserving the human redox balance and preventing a number of oxidative stress-related chronic degenerative diseases. In our ongoing investigation of polyphenol-rich plants in search of novel molecules, we resumed the investigation of Lawsonia inermis L. (Lythraceae) or henna, a popular ancient plant with aesthetic and therapeutic benefits. The leaves' 70% aq acetone extract was fractionated on a Diaion HP-20 column with different ratios of H2O/an organic solvent. Multistep gel chromatographic fractionation and HPLC purification of the Diaion 75% aq MeOH and MeOH fractions led to a new compound (1) along with tannin-related metabolites, benzoic acid (2), benzyl 6'-O-galloyl-β-D-glucopyranoside (3), and ellagic acid (4), which are first isolated from henna. Repeating the procedures on the Diaion 50% aq MeOH eluate led to the first-time isolation of two O-glucosidic ellagitannins, heterophylliin A (5), and gemin D (6), in addition to four known C-glycosidic ellagitannins, lythracin D (7), pedunculagin (8), flosin B (9), and lagerstroemin (10). The compound structures were determined through intensive spectroscopic investigations, including HRESIMS, 1D (1H and 13C) and 2D (1H-1H COSY, HSQC, HMBC, and NOESY) NMR, UV, [α]D, and CD experiments. The new structure of 1 was determined to be a megastigmane glucoside gallate; its biosynthesis from gallic acid and a β-ionone, a degradative product of the common metabolite β-carotin, was highlighted. Cytotoxicity investigations of the abundant ellagitannins revealed that lythracin D2 (7) and pedunculagin (8) are obviously more cytotoxic (tumor specificity = 2.3 and 2.8, respectively) toward oral squamous cell carcinoma cell lines (HSC-2, HSC-4, and Ca9-22) than normal human oral cells (HGF, HPC, and HPLF). In summary, Lawsonia inermis is a rich source of anti-oral cancer ellagitannins. Also, the several discovered polyphenolics highlighted here emphasize the numerous biological benefits of henna and encourage further clinical studies to profit from their antioxidant properties against oxidative stress-related disorders.

Dietary Polyphenols as Prospective Natural-Compound Depression Treatment from the Perspective of Intestinal Microbiota Regulation

The broad beneficial effects of dietary polyphenols on human health have been confirmed. Current studies have shown that dietary polyphenols are important for maintaining the homeostasis of the intestinal microenvironment. Moreover, the corresponding metabolites of dietary polyphenols can effectively regulate intestinal micro-ecology and promote human health. Although the pathogenesis of depression has not been fully studied, it has been demonstrated that dysfunction of the microbiota-gut-brain axis may be its main pathological basis. This review discusses the interaction between dietary polyphenols and intestinal microbiota to allow us to better assess the potential preventive effects of dietary polyphenols on depression by modulating the host gut microbiota.

Design, Characterization, and Antimicrobial Evaluation of Copper Nanoparticles Utilizing Tamarixinin a Ellagitannin from Galls of Tamarix aphylla

The application of plant extracts or plant-derived compounds in the green synthesis of metal nanoparticles (NPs) was researched. Determining the exact metabolite implicated in the formation of NPs would necessitate comprehensive investigations. Copper nanoparticles (CuNPs) are gaining a lot of attention because of their unique properties and effectiveness against a wide range of bacteria and fungi, as well as their potential for usage in catalytic, optical, electrical, and microelectronics applications. In the course of this study, we aimed to formulate CuNPs utilizing pure tamarixinin A (TA) ellagitannin isolated from Tamarix aphylla galls. The main particle size of the formed CuNPs was 44 ± 1.7 nm with zeta potential equal to −23.7 mV, which emphasize the stability of the CuNPs. The X-ray diffraction spectroscopy showed a typical centered cubic crystalline structure phase of copper. Scanning electron microscopy images were found to be relatively spherical and homogeneous in shape. The antimicrobial properties of TA, as well as its mediated CuNPs, have been evaluated through well diffusion assays against four bacterial, Bacillus subtilis NCTC 10400, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 27853, and two fungal, Candida albicans and Aspergillus flavus, strains. The distinctive antimicrobial activities were noted against the fungal strains and the Gram-negative bacterial strains P. aeruginosa ATCC 27853, and E. coli ATCC 25922. In conclusion, CuNPs mediated by TA can be applied for combating a wide range of bacterial and fungal species especially C. albicans, Asp. flavus, and P. aeruginosa in a variety of fields.