Blanching alters the phenolic constituents and in vitro antioxidant and anticholinesterases properties of fireweed [Crassocephalum crepidioides]

Objective: This research investigated the effect of blanching on the phenolic distribution and in vitro antioxidant and anticholinesterase properties of the HCl-methanolic extracts from fireweed

Methods: Phenolic-rich extracts were prepared by extracting the powdered blanched and unblanched fireweed leaves with a mixture of absolute 1 M HCl and methanol [1:1 v/v]. The phenolic constituents were analysed using high-performance chromatography coupled to a diode array detector [HPLC-DAD]. Furthermore, the extracts' in vitro antioxidant [1,1-diphenyl-2-picrylhydrazyl [DPPH], 2,2-azinobis[3-ethylbenzo-thiazoline-6-sulfonate [ABTS] radical scavenging and Fe[2+] chelating abilities and inhibition of Fe[2+]-induced lipid peroxidation in isolated rat brain] properties and inhibitory effects against acetylcholinesterase [AChE] and butyrylcholinesterase [BChE] were determined in vitro

Results: The HPLC-DAD analysis detected four phenolic acids [gallic, chlorogenic, caffeic and ellagic acids] and three flavonoids [catechin, rutin and quercetin] that were abundant in the unblanched fireweed extract. The findings further showed that the unblanched fireweed extract had higher antioxidant and AChE and BChE inhibitory properties compared to the blanched fireweed extract

Conclusion: The increased antioxidant and anticholinesterase properties of the unblanched fireweed extract could be linked to its higher concentrations of the phenolic constituents compared to the blanched firewood. Therefore, blanching leads to a decrease in the antioxidant and anticholinesterase properties of fireweed, as evidenced by a reduction/loss in the polyphenolic content from the blanched fireweed

Antioxidant effects of Phyllanthus niruri tea on healthy subjects

OBJECTIVE@#To investigate the potential antioxidant effects of Phyllanthus niruri (P. niruri, Euphorbiaceae) tea on healthy subjects.@*METHODS@#Five non-smoking, male healthy volunteers, 20 to 31 years old, were enrolled. Each subject was treated twice, following a randomized crossover fashion regarding the ingestion of P. niruri infusion (5 g/750 mL) (tea group) or 750 mL of water (control group). Fasting venous blood samples were collected prior to and at 1, 2 and 4 h after infusion drinking. Samples were tested for plasmatic gallic acid and ascorbic acid levels, erythrocytic catalase and superoxide dismutase activities, and intracellular DCFH fluorescence in granulocytes, monocytes and lymphocytes.@*RESULTS@#Catalase and superoxide dismutase activities were not altered by tea ingestion. Plasma levels of gallic acid were significantly increased at 1, 2 and 4 h after P. niruri ingestion and plasma ascorbic acid at 1 h after P. niruri ingestion.@*CONCLUSIONS@#Ingestion of P. niruri tea is associated with a slight increase in antioxidant markers in human blood (ascorbic acid and gallic acid), which may contribute to its pharmacological effects.

In Vitro Trypanocidal Activity of Macela (Achyrocline satureioides) Extracts against Trypanosoma evansi

The aim of this study was to verify the trypanocidal effectiveness of aqueous, methanolic, and ethanolic extracts of Achyrocline satureioides against Trypanosoma evansi in vitro. A. satureioides extracts, known as macela, were used on trypomastigotes at different concentrations (1, 5, 10, 50, 100, 500, and 1,000 microg/ml) and exposure times (0, 1, 3, 6, and 9 hr). A dose-dependent effect was observed when the 3 extracts were tested. The concentrations of 1, 5, and 10 microg/ml were not able to kill trypomastigotes until 3 hr after exposure, and the highest concentrations (500 and 1,000 microg/ml) were able to kill all trypomastigotes after 1 hr. When the time of exposure was increased up to 9 hr, the concentrations at 50 and 100 microg/ml were 100% effective to 3 extracts. The chemical analysis of the extracts revealed the presence of flavonoids, a trypanocidal compound already described. Based on the results, we can conclude that the A. satureioides extracts exhibit trypanocidal effects.