In vitro assessment of antioxidant,neuroprotective,anti-urease and anti-tyrosinase capacities of Tamarix africana leaves extracts

OBJECTIVE:To characterize the chemical profile of methanolic crude extract and its fractions(Ethyl acetate,n-butanol and aqueous)using liquid chromatographymass spectrometry(LC-MS)analysis,to evaluate their biological and pharmacological properties:antioxidant(1,1-diphenyl-2-pycrylhydrazyl(DPPH),2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic)(ABTS·+),galvinoxyle free radical scavenging,reducing power,phenanthroline andβcarotene-linoleic acid bleaching assays),enzymes inhibitory ability against several enzymes[acetylcholinesterase(AChE),buthyrylcholinesterase(BChE),urease and tyrosinase].METHODS:Secondary metabolites were extracted from Tamarix africana air-dried powdered leaves by maceration,the crude extract was fractionated using different solvents with different polarities(Ethyl acetate,n-butanol and aqueous).The amount of polyphenols,flavonoids and tannins(hydrolysable and condensed)were determined using colorimetric assays.A variety of in vitro biochemical tests were carried out to assess antioxidant and oxygen radical scavenging properties using DPPH,ABTS,galvinoxyle free radical scavenging,reducing power,phenanthroline andβcarotene-linoleic acid bleaching methods.Neuroprotective effect was examined against acetylcholinesterase and buthyrylcholinesterase enzymes.The anti-urease and antityrosinase activities were performed against urease and tyrosinase enzymes respectively.The extract’s components were identified using LC-MS and compared to reference substances.RESULTS:The results indicated that Tamarix africana extracts presented a powerful antioxidant activity in all assays and exhibited a potent inhibitory effect against AChE and BChE as well as urease and tyrosinase enzymes.LC-MS analysis identified amount of eight phenolic compounds were revealed in this analysis;Apigenin,Diosmin,Quercetin,Quercetine-3-glycoside,Apigenin 7-O glycoside,Rutin,Neohesperidin and Wogonin in methanolic extract and its different fractions of Tamarix africana from leaves.CONCLUSIONS:Based on these findings,it is reasonable to assume that Tamarix africana could be considered as a potential candidate for pharmaceutical,cosmetics,and food industries to create innovative health-promoting drugs.

Photoprotective Effect of the Hydroalcoholic Extract from Red and Black Peruvian Varieties of <i>Phaseolus vulgaris</i>L.

Introduction: Ultraviolet radiation can be harmful to the skin and can create serious problems when a protective substance or equipment is not used regularly, for this reason the present study set out to evaluate the photoprotective effect of the hydroalcoholic extracts of the integument of the red and black varieties of pop beans (Phaseolus vulgaris). Materials and Method: The extracts were obtained by macerating the tegument of the two varieties of pop beans, black and red, in an ethanol/water (80:20) solution. The thin-layer chromatographic method was used to observe anti-tyrosinase activity, using the 0.05% kojic acid standard as a positive control. The photoprotective effect was evaluated in female mice of seven-week-old, Mus musculus Balb/c, with shaved back and exposed to UV-C radiation for 30 minutes once a day for thirty days to induce photo-damage in the skin. The treatments consisted in the application of extracts at 2% and 5% W/V in gel on the shaved area. Only the gel formulation, sunscreen or no treatment at all was used for the control group. Acute photodamage was quantified using the Draize scale, measuring the degree of erythema and edema;and the degree of photoaging using the Glogau scale at 7 days and 30 days. Results: It was found that the ethanolic extracts of the integument of both varieties of Phaseolus vulgaris, red and black, are practically non-toxic in mice by oral and dermal routes at a limit dose of 5000 mg/kg. The anti-tyrosinase effect at a qualitative level, evaluated by thin layer chromatography, showed the black variety were more active than the red one and both can be compared to the activity of the kojic acid. The two extracts of the two varieties showed photoprotective effect, however the extracts in 5% gel to a greater degree. Conclusions: It was concluded that the hydroalcoholic extract of the pop black beans tegument at 5% in gel has photoprotective effect.

Syntheses of phenyl benzoate compounds and their bioactivity investigation

Eight phenyl benzoate compounds were synthesized in one step, and then their antioxidant, anti-tyrosinase, and anti-pancreatic lipase activities were evaluated in the present study. The total yields ranged from 31% to 85%. Compound 4 c exhibited a stronger antioxidant activity compared with Trolox, with half maximal inhibitory concentrations(IC50) of approximately 13.06 μM, and the antioxidant mechanism was further studied using computational chemistry. Compounds 1 c–5 c exhibited minimal anti-tyrosinase activity. Compounds 4 c, 5 d, 6 c and 6 d exhibited weak anti-pancreatic lipase activity, with an inhibition rate of 33.52%, 15.76%, 18.37% and 20.77%, respectively. These results demonstrated that all compounds had reference significance, especially compound 4 c.

The phytochemical,proximate,pharmacological,GC-MS analysis of Cyperus esculentus(Tiger nut):A fully validated approach in health,food and nutrition

Cyperus esculentus(Tiger nut)has been grossly underutilized and unexploited despite its nutritional and medicinal potentials.This research aimed to evaluate the phytochemical,proximate,GC-MS and pharmacological properties such as antioxidant,anticancer,anti-elastase,anti-melanogenic and anti-tyrosinase activity in ethanol and n-hexane extracts of tiger nut.The pharmacological activities were measured using spectrophotometry,agar well diffusion,MCF-7 and HeLa cell methods.The tiger nut extracts(ethanol and n-hexane)in the phytochemical and proximate analysis showed the existence of bioactive compounds such as alkaloids,glycosides,flavonoids,crude fibres,tannins,proteins,carbohydrates,oxalates,phytates and fats content.The ethanol extract showed superior pharmacological(anticancer,antibacterial,anti-melanogenic and antioxidant)activities,especially against the MCF-7 cell line.The results for scavenging activity of ethanol extract(IC_(50)=535.57μg/mL)showed significant differences(p<0.05)when compared with n-hexane extract(IC_(50)=645.5μg/mL).The GC-MS assessment of both extracts showed the existence of bioactive compounds.Different concentrations(100,200 and 350 mg/mL)of tiger nut extracts against Shigella sp.,Salmonella sp.,Staphylococcus aureus and Escherichia coli demonstrated the highest level of inhibitions at 350 mg/mL.The findings of the current research showed that tiger nut has a high content of nutrients and bioactive phytochemicals.

Synthesis of prenylated and geranylated xanthones and their bioactivities

Nine prenylated and geranylated xanthones were synthesized in two steps with total yields ranging from 11%to 36%.All of the compounds were first reported.Then,the antitumor,anti-tyrosinase,anti-pancreatic lipase,antifungal and antibacterial activities of all or part of compounds 1–9 were evaluated.Compound 9 exhibited clear antitumor activity,and its cytotoxicity against MCF-7 and MDA-MB-231 cells was stronger compared with cisplatin.Compounds 1–4 and 6–7 also exhibited certain activity other than the antitumor activity described above.These results demonstrated that compounds 1–4,6–7 and 9 were very promising leads for further structural modification.