Caracterização química e avaliação das atividades biológicas de extratos glicólicos de Cecropia pachystachya Trécu

Abstract

Cecropia pachystachya Trécul popularly known as embaúba, imbaúba andumbaúba, the plant is widelydistributed in Brazil. The speciebelongs to Urticaceaefamily in the Cecropiagenus. Its leaves revealed an important anti-inflammatory, healing and hypoglycemic activity. Glycolic extractsof C. pachystachyawere not reported in the literature yet. Therefore, the followed work aimed to evaluate the chemical and biological activity of Cecropia pachystachya, for the development of cutaneous phytocosmetics products. For this reason, dried and crushed leaves were submitted to maceration with propylene glycol (PG), glycerin (GLY) and grainalcohol (GA).After vacuum filtration two extracts were obtained by two different solvents 1) GLY:GA(70:30 v/v) (EGCP01) e 2) PG:GA(70:30 v/v) (EGCP02).The chemical characterization of each extract was performed by chromatographic methods.Antioxidant activity was evaluated in vitro by DPPH reduction assay, β-carotene/linoleic acid method and by inhibition of nitric oxide production.The antimicrobial potential was determined by minimum inhibitory concentration (MIC) against Staphylococcus aureus(ATCC®25923™), Staphylococcus epidermidis(ATCC®0016™) and Streptococcus pyogenes(ATCC®19615™)strains. The depigmenting activity of glycolic extracts was assessed by enzymatic inhibition of tyrosinase.Cell viability was investigated in fibroblast (L929) and keratinocyte (HaCaT) lines by reducing MTT to formazan. The obtained glycolic extracts are in liquid form and presenteda homogeneous appearance.Regarding coloration, EGCP01 extract was characterized as light brown andEGCP02 in dark green.The concentration for EGCP01 and EGCP02 was 33.1 mg/mL and 36.6 mg/mL, respectively. The EGCP01 extract showed a greater extraction capacity for phenolic compounds and flavonoids when compared toEGCP02 extract.5-O-caffeoylquinic acid was identified and quantified by HPLC-UV, 3,27 ± 0,31 and 8,45 ± 0,24 mg/g for the respective extractsEGCP01 andEGCP02. After HPLC-MS , negative mode, the followed compounds were suggested: quinic acid (m/z191), chlorogenic acid (m/z353), procyanidins B2, B3 and/or B5 (m/z577), procyanidin C1 (m/z865), catechin/epicatechin (m/z289), cinchona Ib/Ia (m/z451), orientin/isoorientin (m/z447), 2"-O-xylosyl-isoorientin (m/z579), isovitexin/vitexin (m/z431) and rutin (m/z609).The extracts were considered statistically similar to standardquercetin forDPPH reduction assay.In the β-carotene/linoleic acid method, the IC(50)values presented by EGCP01 and EGCP02 were 8.25 ± 1.03 μg/mL and 6.82 ± 0.57 μg/mL,respectively.Regardingthe inhibition of NO production, the values for concentrations of 400; 200; 100; 50; 25; 12.5 μg/mL were respectively 71.48; 45.58; 33.72; 23.56; 12.76; 10.84% for EGCP01 and 45.16; 38.02; 29.01; 21.62; 5.22; 1.14% for EGCP02. In relation to antimicrobial activity, both extracts showed a MIC of 500 μg/mL for S. aureusand S. pyogenes.Considering S. epidermidisstrain, theobtainedMIC for EGCP01 and EGCP02extracts were250 μg/mL. A high inhibitory activity on tyrosinase was observed, with IC(50)of 49.42 ± 10.49 μg/mL and 57.92 ± 0.11 μg/mL for EGCP01 and EGCP02extracts, respectively.In addition, the extracts maintained the cell viability for L929 and HaCaT at all tested concentrations (35 to 2.20 μg/mL). Based on the found results, it wasconcluded that the glycolic extracts showed promising physical-chemical and biological characteristics for incorporation in cutaneous cosmetic formulations.