1H NMR and HPLC-DAD-MS for the characterization of ellagitannins and triterpenoids of less investigated Anogeissus leiocarpus DC (Combretaceae) stem bark

Mechanistic Insights into the Biological Effects and Antioxidant Activity of Walnut (Juglans regia L.) Ellagitannins: A Systematic Review

Walnuts (Juglans regia L.) are an important source of ellagitannins. They have been linked to positive effects on many pathologies, including cardiovascular disorders, neurodegenerative syndromes, and cancer. The limited bioavailability of ellagitannins prevents them from reaching significant circulatory levels, despite their antioxidant, anti-inflammatory, and chemopreventive properties. Urolithins are ellagitannin gut microbiota-derived metabolites. They have better intestinal absorption and may be responsible for the biological activities of ellagitannins. Recent evidence showed that walnut ellagitannins and their metabolites, urolithins, could have positive outcomes for human health. This study aims to synthesize the current literature on the antioxidant activity and mechanistic pathways involved in the therapeutic potential of walnut ellagitannins and their metabolites. In the eligible selected studies (n = 31), glansreginin A, pedunculagin, and casuarictin were the most prevalent ellagitannins in walnuts. A total of 15 urolithins, their glucuronides, and sulfate metabolites have been identified in urine, blood, feces, breast milk, and prostate tissue in analyzed samples. Urolithins A and B were associated with antioxidant, anti-inflammatory, cardioprotective, neuroprotective, anticarcinogenic, and anti-aging activities, both in preclinical and clinical studies. Despite the promising results, further well-designed studies are necessary to fully elucidate the mechanisms and confirm the therapeutic potential of these compounds in human health.

Anogeissus leiocarpus (DC.) Guill. & Perr. (Combretaceae): A review of the traditional uses, phytochemistry and pharmacology of African birch

Anogeissus leiocarpus (DC.) Guill. & Perr. belongs to the family Combretaceae and is used both by African traditional medical practitioners and livestock rearers to treat diseases such as African trypanosomiasis, animal diarrhoea, asthma, cancer, cough, diabetes, dysentery, erectile dysfunction, fever, giardiasis, helminthiases, meningitis, menstrual disorders, monkeypox, oral infections, poliomyelitis, sickle cell anaemia, snake bites, toothache, urinary schistosomiasis, and yellow fever. Some of these activities have been associated with the presence of polyphenols in the plant which include ellagic acid derivatives, flavonoids, stilbenes, tannins, and triterpenes. Several bioactive molecules have been identified from A. leiocarpus. These include the main active constituents, ellagitannins, ellagic acid derivates, flavonoids and triterpenes. Pharmacological studies have confirmed its antibacterial, antifungal, antihyperglycemic, antihypertensive, antimalarial, antioxidative, antiparasitic, antitumour and anti-ulcer effects. The stem bark has been investigated mainly for biological activities and phytochemistry, and it is the most mentioned plant part highlighted by the traditional users in ethnomedicinal surveys. In vitro and in vivo models, which revealed a wide range of pharmacological actions against parasites causing helminthiasis, leishmaniasis, malaria and trypanosomiasis, have been used to study compounds from A. leiocarpus. Because of its uses in African traditional medicine and veterinary practices, A. leiocarpus has received considerable attention from researchers. The current review provides a comprehensive overview and critical appraisal of scientific reports on A. leiocarpus, covering its traditional uses, pharmacological activities and phytochemistry.

Integrated mass spectrometry imaging and single-cell transcriptome atlas strategies provide novel insights into taxoid biosynthesis and transport in Taxus mairei stems

Taxol, which is a widely used important chemotherapeutic agent, was originally isolated from Taxus stem barks. However, little is known about the precise distribution of taxoids and the transcriptional regulation of taxoid biosynthesis across Taxus stems. Here, we used MALDI-IMS analysis to visualize the taxoid distribution across Taxus mairei stems and single-cell RNA sequencing to generate expression profiles. A single-cell T. mairei stem atlas was created, providing a spatial distribution pattern of Taxus stem cells. Cells were reordered using a main developmental pseudotime trajectory which provided temporal distribution patterns in Taxus stem cells. Most known taxol biosynthesis-related genes were primarily expressed in epidermal, endodermal, and xylem parenchyma cells, which caused an uneven taxoid distribution across T. mairei stems. We developed a single-cell strategy to screen novel transcription factors (TFs) involved in taxol biosynthesis regulation. Several TF genes, such as endodermal cell-specific MYB47 and xylem parenchyma cell-specific NAC2 and bHLH68, were implicated as potential regulators of taxol biosynthesis. Furthermore, an ATP-binding cassette family transporter gene, ABCG2, was proposed as a potential taxoid transporter candidate. In summary, we generated a single-cell Taxus stem metabolic atlas and identified molecular mechanisms underpinning the cell-specific transcriptional regulation of the taxol biosynthesis pathway.

Effect of the Standardized ZnO/ZnO-GO Filter Element Substrate driven Advanced Oxidation Process on Textile Industry Effluent Stream: Detailed Analysis of Photocatalytic Degradation Kinetics

A simple process of synthesizing coated filter element substrates (FES) containing zinc oxide (ZnO) nanorods and ZnO graphene-oxide nanocomposite for a pilot-scale industrial dye-effluent treatment plant is proposed. This work reports a detailed analysis of the photocatalysis mechanism on real industrial effluent streams containing a mixture of dyes. The analysis is very relevant for conducting advanced oxidation process-assisted effluent remediation at a field-level treatment operation. Estimation of the dye concentration shows nearly complete (≥98%) degradation from an initial dye sample concentration. A detailed study for the analysis of the initial reactive dyes and their degradation products was performed for quantification and identification of the degradation products through various spectral techniques. A design of the remediation mechanism through degradation pathways is proposed for characterizing the organic compounds in the degraded dye products. A regeneration and reusability study was performed on the FES presenting the durability of the FES-designed synthesis process originally for 11 cycles and regenerated FES for six cycles for achieving a threshold of 60% degradation efficiency. The experimental results demonstrate the efficacy of FES through the designed immobilized approach for the complete remediation of textile dye effluents for a 4 h treatment plant process and the consistent operability of the FES for the combined dye wastewater treatment operations.

Ellagitannins and triterpenoids extracts of Anogeissus leiocarpus stem bark extracts: Protective effects against osteoarthritis

Osteoarthritis (OA) is a complex joint disease characterized by persistent pain. Unfortunately, current pharmacological therapies are unsatisfactory and characterized by side effects, reason why new strategies are needed. We tested the efficacy of different classes of compounds, ellagitannins and olean-type triterpenoids, contained in Anogeissus leiocarpus extract (Combretaceae family) in comparison to ellagitannins of Castanea sativa extract in a rat model of osteoarthritis induced by the intra-articular injection of sodium monoiodoacetate (MIA). The decoction of stem bark of A. leiocarpus AL-DEC-TOT (300 mg/kg; 4.8% triterpenoids; 11.0% tannins), the butanol extract AL-BuOH-EXT (120 mg/kg; triterpenoids 20.9%; tannins 6.4%) and its correlated aqueous residue AL-Res-H₂ O (300 mg/kg; triterpenoids 0.7%; tannins 8.7%) and the decoction of C. sativa, CS-DEC-TOT, (240 mg/kg; triterpenoids 0.65%; tannins 10.8%) were orally administered for two weeks starting from the day of the damage. Behavioural tests highlighted that all stem bark extracts of A. leiocarpus counteracted hypersensitivity development, reduced spontaneous pain, and improved motor skills. Histologically, AL-DEC-TOT, AL-BuOH-EXT and AL-Res-H₂ O were effective in preventing joint alterations. In conclusion, all the extracts were effective demonstrating that both olean-type triterpenoid and ellagitannin fractions have anti-hypersensitivity and restorative properties running the stem bark extracts of A. leiocarpus as a candidate in the treatment of OA.

Evaluation of Antiproliferative, Antimicrobial, Antioxidant, Antidiabetic and Phytochemical Analysis of Anogeissus dhofarica A. J. Scott

In the current study, methanol (ADAM) extracts and their fractions, including chloroform (ADAC), ethyl acetate (ADAE), n-hexane (ADAH), and aqueous (ADAA) fractions, were prepared from aerial parts of Anogeissus dhofarica and evaluated for phytochemical assessment, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) analysis, and in vitro bioassays. The qualitative analysis determined that, except alkaloids, all the representative groups were found to be present in the analyzed samples. Samples under quantitative study displayed the highest amount of total phenolic contents in the ADAE fraction, while total flavonoid contents were highest in the ADAM extract. The ADAM extract was subjected to HR-ESI-MS to identify the chemical constituents that presented twenty-two bioactive ingredients, outlined for the first time from A. dhofarica, mainly contributed by sub-class flavanones. In the case of antimicrobial activity, the ADAE extract revealed an effective zone of inhibition (ZOI) against the Gram-positive bacterial strain (Staphylococcus aureus) with an MIC value of 0.78 ± 0.3 mg/mL, while the ADAA extract exhibited higher ZOI (34 ± 0.12 mm) against the fungal strain Candida kruzei with an MIC of 0.78 mg/mL. In the DPPH (2,2-diphenyl-1-picrylhydrazyl) analysis, the ADAE extract exhibited a maximum scavenging potential with an IC₅₀ of 9.8 ± 1.2 μg/mL, succeeded by the ADAM extract with an IC50 of 17.4 ± 0.4 μg/mL free radical scavenging capability. In the antidiabetic assessment, the ADAE extract was the most effective, with an IC₅₀ of 6.40 ± 0.1 μg/mL, while the same extract demonstrated prominent activity with 30.8% viability and an IC₅₀ of 6.2 ± 0.3 μg/mL against breast cancer cell lines. The brine shrimp lethality assay demonstrated a correlation with the in vitro cytotoxicity assay, showing the ADAE extract as the most active, with a 70% mortality rate and an LC₅₀ of 300.1 μg/mL. In conclusion, all the tested samples, especially the ADAE and ADAM extracts, have significant capabilities for the investigated activities that could be due to the presence of the bioactive compounds.

Antidiabetic and antioxidant potential of total extract and supernatant fraction of the roots of Anogeissus leiocarpus in HFD-fed and Streptozocin -induced diabetic rats

The aim of this study was to evaluate the antidiabetic properties of hydro alcoholic extract and supernatant fraction of the roots of Anogeissus leiocarpus, a plant used by traditional healers to treat Diabetes mellitus. Diabetes mellitus was induced by a single intraperitoneal administration of Streptozocin to Sprague Dawley rats under a fructose-enriched fat diet. Diabetic rats were treated with 500 mg/kg of total extract and 100 mg/kg of supernatant. The antidiabetic activity was assessed by measuring blood glucose level, lipid profile, insulin and biochemical parameters together with the antioxidant potential. The administration of total extract and supernatant exhibited significant decrease (p < 0.01) of the blood glucose level in the diabetic rats after 7 days of treatment compared to the diabetic rats. A significant reduction in the serum concentrations of cholesterol (19.7 %) and triglycerides (56.7 %) was observed in the treated diabetic rats. The levels of insulin did not differ across all the groups. However, compared to diabetic rats, HOMA-IR (Homeostasis Model Assessment for Insulin-resistance) and HOMA-β (Homeostasis Model Assessment for β cell function) showed a statistical decrease in insulin resistance and an increase in pancreatic β cell function in the treated diabetic rats. Moreover, total extract and supernatant significantly increased GSH level and decreased lipid peroxidation because of their antioxidant properties. In comparison, the supernatant fraction exerted stronger antidiabetic and antioxidant effects than the total extract. Hence, the roots of Anogeissus leiocarpus are a potent antidiabetic agent that can be developed as an alternative medicine for diabetes and its complications.