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Reactive oxygen species (ROS) are involved in the pathophysiology of several health disorders, among others inflammation. Polyphenols may modulate ROS related disorders. In this work, thirty-two phenolic compounds were tentatively identified in a leaf extract from Eugenia supra-axillaris Spring. ex Mart. using HPLC-MS/MS, five of which were also individually isolated and identified. The extract displayed a substantial in vitro antioxidant potential and was capable of decreasing ROS production and hsp-16.2 expression under oxidative stress conditions in vivo in the Caenorhabditis elegans model. Also, the extract showed higher inhibitory selectivity towards COX-2 than COX-1 in vitro with higher selectivity towards COX-2 than that of diclofenac. The extract also exhibited anti-inflammatory properties: It attenuated the edema thickness in a dose dependent fashion in carrageenan-induced hind-paw odema in rats. In addition, the extract reduced the carrageenan-induced leukocyte migration into the peritoneal cavity at the highest dose. Furthermore, the extract showed antipyretic and analgesic activities in a mouse model. Eugenia supra-axillaris appears to be a promising candidate in treating inflammation, pain and related oxidative stress diseases.

In the current work, the phytochemical composition of a leaf methanol extract from Albizia anthelmintica was thoroughly investigated. The antioxidant, anti-inflammatory, analgesic, and antipyretic activities of the extract were investigated. In the carrageenan induced hind paw edema bioassay; the extract significantly reduced the edema thickness in rats and diminished the leukocyte migration to the peritoneal cavity in mice. The extract exhibited central and peripheral anti-nociceptive effects; it significantly decreased the number of acetic acid induced writhes and prolonged the latency time in the hot plate test. The extract showed a substantial antipyretic activity as it decreased significantly the elevated rectal temperature in mice after intraperitoneal injection of Brewer's yeast. Molecular docking of some major compounds in the extract to COX-1, COX-2 and 5-LOX, enzymes involved in the inflammation cascade, revealed appreciable interactions with the conserved amino acid residues in these target proteins. These findings were confirmed with in vitro enzyme inhibitory assays in which the extract showed IC 50 values of 4.11, 0.054, and 1.74 μg/mL towards COX-1, COX-2 and 5-LOX, respectively. The extract displayed solid antioxidant properties as well with a TAC value of 35.13 U/L and EC 50 of 5.36 μg/mL in DPPH assay. These findings suggested that Albizia anthelmintica is a good antioxidant with potential therapeutic efficacy for treating inflammation, pain and related oxidative stress disorders., (Copyright © 2019 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Ethnopharmacological Relevance: Cassia abbreviata is a small to medium sized branched umbrella-shaped deciduous tree. It is widely spread in the tropics, especially in Africa, having a long history in traditional medicine for the treatment of numerous conditions such as headaches, diarrhea, constipation, some skin diseases, malaria, syphilis, pneumonia, stomach troubles, uterine pains, and against gonorrhea., Aim of the Study: We investigated the phytochemical constituents of a root extract from Cassia abbreviata using HPLC-PDA-ESI-MS/MS. We also determined the antioxidant activities in vitro and in vivo using the nematode Caenorhabditis elegans as a model organism. The hepatoprotective activities in case of D-galactosamine (D-GaIN)-induced hepatotoxicity were studied in a rat model., Materials and Methods: HPLC-PDA-ESI-MS/MS analysis allowed the identification of the secondary metabolites of the methanol extract. DPPH and FRAP assays were used to determine the antioxidant activities in vitro. Using the C. elegans model, survival rates under juglone induced oxidative stress, intracellular ROS content, quantification of Phsp-16.2: GFP expression and subcellular DAF-16: GFP localization were investigated to determine the antioxidant activities in vivo. The in vivo hepatoprotective potential of the root extract was evaluated for D-galactosamine (D-GaIN)-induced hepatotoxicity in rats. The activity of the liver enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (GGT), in addition to liver peroxidation product malondialdehyde (MDA) and glutathione content (GSH), as well as albumin and total bilirubin concentration, were determined. A histopathological study was also performed., Results and Conclusions: C. abbreviata root extract is rich in polyphenolics, particularly proanthocyanidins. HPLC-PDA-ESI-MS/MS analysis resulted in the identification of 57 compounds on the bases of their mass spectra. (epi)-Catechin, (epi)-afzelechin, (epi)-guibourtinidol, and (ent)-cassiaflavan monomers as well as their dimers, trimers, and their diastereomers are the main components of the extract. The total phenolic content amounted for 474mg/g root extract expressed as gallic acid equivalent using the Folin-Ciocalteu method. The extract exhibited powerful antioxidant activity with EC 50 of 6.3μg/mL in DPPH and 19.15mM FeSO 4 equivalent/mg sample in FRAP assay. In C. elegans model, the extract (200μg/mL) was able to increase the survival rate by 44.56% and reduced the ROS level to 61.73%, compared to control group. Pretreatment of rats with 100mg extract/kg (b. wt.) reduced MDA by 47.36% and elevated GSH by 59.1%. The extract caused a significant reduction of ALT, AST and GGT activities by 11%, 35.7% and 65%, respectively. The findings of this study suggest that the proanthocyanidin-rich extract from C. abbreviata may be an interesting candidate for hepatoprotective activity in case of hepatocellular injury., (Copyright © 2017 Elsevier B.V. All rights reserved.)

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., Competing Interests: The authors declare no conflict of interest.

Background: Liver diseases and diabetes are serious health disorders associated with oxidative stress and ageing. Some plant polyphenols can lower the risk of these diseases., Purpose: We investigated the phytochemical profiling of a root extract from Ximenia americana var. caffra using HPLC-PDA-ESI-MS/MS. The antioxidant activities in vitro were investigated. The hepatoprotective activities were studied in rat models with d-galactosamine (d-GaIN)-induced hepatotoxicity and the antidiabetic activities in STZ-diabetic rats were also investigated., Materials and Methods: HPLC-PDA-ESI-MS/MS was used to identify plant phenolics. The antioxidant activities in vitro were determined using DPPH and FRAP assays. The in vivo hepatoprotective activities were determined for d-GaIN-induced hepatotoxicity in rats. We determined the liver markers alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (GGT), liver peroxidation product malondialdehyde (MDA), glutathione content (GSH), albumin and total bilirubin concentration. The histopathological changes in rat liver were also studied. The antidiabetic activities were also investigated in STZ-diabetic rats and serum glucose, serum insulin hormone, and lipid peroxides were determined., Results: The root extract is rich in tannins with 20 compounds including a series of stereoisomers of (epi)catechin, (epi)catechin-(epi)catechin, (epi)catechin-(epi)catechin-(epi)catechin, and their galloyl esters. Promising antioxidant potential was observed in vitro in DPPH assay with EC 50 of 6.5 µg extract / 26 µg raw material and in FRAP assay with 19.54 mM FeSO 4 compared with ascorbic acid (EC 50 of 2.92 µg/ml) and quercetin (FeSO 4 24.04 mM/mg), respectively. Significant reduction of serologic enzymatic markers and hepatic oxidative stress markers such as ALT, AST, MDA, GGT, and total bilirubin, as well as elevation of GSH and albumin were observed in rats with d-galactosamine-induced liver damage treated with the extract. These findings agree with a histopathological examination suggesting a hepatoprotective potential for the root extract. The root extract can mediate an antidiabetic effect by reducing elevated blood glucose and serum lipid peroxides levels and by increasing insulin in STZ-diabetic rats by -107, -31.1, +11.3%, respectively., Conclusions: The results of this study suggest that the tannin-rich extract from Ximenia americana var. caffra could be an interesting candidate for the treatment of several health disorders associated with oxidative stress such as hepatocellular injury and diabetes., (Copyright © 2017. Published by Elsevier GmbH.)

Natural products are considered as an important source for the discovery of new drugs to treat aging-related degenerative diseases and liver injury. The present study profiled the chemical constituents of a methanol extract from Senna singueana bark using HPLC-PDA-ESI-MS/MS and 36 secondary metabolites were identified. Proanthocyanidins dominated the extract. Monomers, dimers, trimers of (epi)catechin, (epi)gallocatechin, (epi)guibourtinidol, (ent)cassiaflavan, and (epi)afzelechin represented the major constituents. The extract demonstrated notable antioxidant activities in vitro: In DPPH (EC 50 of 20.8 µg/mL), FRAP (18.16 mM FeSO₄/mg extract) assays, and total phenolic content amounted 474 mg gallic acid equivalent (GAE)/g extract determined with the Folin-Ciocalteu method. Also, in an in vivo model, the extract increased the survival rate of Caenorhabditis elegans worms pretreated with the pro-oxidant juglone from 43 to 64%, decreased intracellular ROS inside the wild-type nematodes by 47.90%, and induced nuclear translocation of the transcription factor DAF-16 in the transgenic strain TJ356. Additionally, the extract showed a remarkable hepatoprotective activity against d-galactosamine (d-GalN) induced hepatic injury in rats. It significantly reduced elevated AST (aspartate aminotransferase), and total bilirubin. Moreover, the extract induced a strong cytoplasmic Bcl-2 expression indicating suppression of apoptosis. In conclusion, the bark extract of S. sengueana represents an interesting candidate for further research in antioxidants and liver protection., Competing Interests: The authors declare no conflict of interest.

Syzygium aqueum is widely used in folk medicine. A polyphenol-rich extract from its leaves demonstrated a plethora of substantial pharmacological properties. The extract showed solid antioxidant properties in vitro and protected human keratinocytes (HaCaT cells) against UVA damage. The extract also reduced the elevated levels of ALT, AST, total bilirubin (TB), total cholesterol (TC) and triglycerides (TG) in rats with acute CCl4 intoxication. In addition to reducing the high MDA level, the extract noticeably restored GSH and SOD to the normal control levels in liver tissue homogenates and counteracted the deleterious histopathologic changes in liver after CCl4 injection. Additionally, the extract exhibited promising anti-inflammatory activities in vitro where it inhibited LOX, COX-1, and COX-2 with a higher COX-2 selectivity than that of indomethacin and diclofenac and reduced the extent of lysis of erythrocytes upon incubation with hypotonic buffer solution. S. aqueum extract also markedly reduced leukocyte numbers with similar activities to diclofenac in rats challenged with carrageenan. Additionally, administration of the extract abolished writhes induced by acetic acid in mice and prolonged the response latency in hot plate test. Meanwhile, the identified polyphenolics from the extract showed a certain affinity for the active pockets of 5-lipoxygenase (5-LOX), cyclooxygenase-1 (COX-1) and cyclooxygenase- 2 (COX-2) explaining the observed anti-inflammatory activities. Finally, 87 secondary metabolites (mostly phenolics) were tentatively identified in the extract based on LCMS/ MS analyses. Syzygium aqueum displays good protection against oxidative stress, free radicals, and could be a good candidate for treating oxidative stress related diseases. [ABSTRACT FROM AUTHOR]