HPLC-DAD-ESI-MS/MS analysis of fruits from Firmiana simplex (L.) and evaluation of their antioxidant and antigenotoxic properties

High resolution UPLC-MS/MS profiling of polyphenolics in the methanol extract of Syzygium samarangense leaves and its hepatoprotective activity in rats with CCl4-induced hepatic damage

Oxidative stress plays a crucial role in the development of several liver diseases. Many natural polyphenols can attenuate oxidative stress and liver injury. In this study, a phytochemical profiling of a methanol extract from leaves of Syzygium samarangense revealed 92 compounds belonging to flavonoids, phenolic acids, condensed tannins, and ellagitannins. The S. samarangense extract exhibited a noticeable antioxidant activity with an EC₅₀ of 5.80 μg/mL measured by DPPH scavenging capacity assay, 2632 Trolox equivalents, 10 mM Fe²⁺ equivalents/mg of samples by TEAC and FRAP assays, respectively. The total phenolic content was 419 mg gallic acid equivalent GAE/g extract. In a cell-based model (HaCaT cells), the extract completely inhibited ROS production induced by UVA, and prevented GSH-depletion and p38 phosphorylation. In addition, the extract exhibited a substantial antioxidant and hepatoprotective activities in CCl₄-treated rats, with an increase in GSH (reduced glutathione) and SOD (superoxide dismutase) activities by 84.75 and 26.27%, respectively, and a decrease of 19.08, 63.05, 52.21, 37.00, 13.26, and 15.15% in MDA, ALT, AST, TB (total bilirubin), TC (total cholesterol), and TG (total glycerides), respectively. These results were confirmed by histopathological analyses. We believe that Syzygium samarangense is a good candidate for further evaluation as an antioxidant and liver protecting drug.

HPLC-PDA-MS/MS Characterization of Bioactive Secondary Metabolites from Turraea fischeri Bark Extract and Its Antioxidant and Hepatoprotective Activities In Vivo

Turraea fischeri is an East African traditional herb, which is widely used in traditional medicine. In this study, we profiled the secondary metabolites in the methanol extract of T. fischeri bark using HPLC-PDA-ESI-MS/MS, and 20 compounds were tentatively identified. Several isomers of the flavonolignan cinchonain-I and bis-dihydroxyphenylpropanoid-substituted catechin hexosides dominated the extract. Robust in vitro and in vivo antioxidant properties were observed in 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay (DPPH) and ferric reducing antioxidant power (FRAP) assay, and in the model organism Caenorhabditis elegans. Additionally, the extract exhibited promising hepatoprotective activities in D-galactosamine (D-GaIN) treated rats. A significant reduction in the elevated levels of aspartate aminotransferase (AST), total bilirubin, gamma-glutamyltransferase (GGT), and malondialdehyde (MDA) and increase of glutathione (GSH) was observed in rats treated with the bark extract in addition to D-galactosamine when compared with rats treated with D-galactosamine alone. In conclusion, T. fischeri is apromising candidate for health-promoting and for pharmaceutical applications.

Polyphenolics from Albizia harveyi Exhibit Antioxidant Activities and Counteract Oxidative Damage and Ultra-Structural Changes of Cryopreserved Bull Semen

Albizia harveyi is a tropical deciduous tree, found across South and Eastern Africa and widely used in traditional medicine. The leaf extract ameliorated the damaging effects of the frozen-thawing process in cryopreserved bull semen. In a dose-dependent pattern, sperm motility, viability, and membrane integrity were improved compared to the untreated control. Furthermore, the extract increased the percentage of viable sperm cells and reduced the percentages of early apoptotic and apoptotic sperm cells as well as the damage in sperm ultra-structure. These activities are in agreement with the robust antioxidant properties in vitro and in the seminal fluid as observed in the total antioxidant capacity and the lipid peroxidation parameter malondialdehyde. LC-MS yielded 35 compounds. The extract was dominated by quercetin-O-galloyl-hexoside and quercetin-O-pentoside, along with other flavonoid glycosides. The polyphenols are probably responsible for the observed activities. In conclusion, the current findings show that A. harveyi leaves are rich in bioactive polyphenols with functional properties, validating its traditional use.