Sinefrina: desenvolvimento e validação de método indicativo da estabilidade e avaliação da toxicidade em extrato seco de Citrus aurantium L

Abstract

The incidence of overweight and obesity in the general population is proving to be a serious public health problem. This fact, coupled with existing parameters of beauty, which consider the thinness, generate an unbridled pursuit for "natural" formulations which contains substances called slimming. In this sense, Citrus aurantium, popularly known as bitter orange, it is being widely used. However, so far there are no methods for quality control of these products and stability studies of its marker, synephrine. Therefore, this study aims to develop and validate the stability indicating method, perform a stability preliminary study and the toxicity of synephrine and photolytic degradation products formed. Stability indicating method was developed by HPLC - PDA for determination of synephrine in Citrus aurantium dry extract. The chromatographic separation used C18 (250 x 4.6 mm, 5μm) column and a mobile phase consisting of acetonitrile: 0.01% orthophosphoric acid (pH 3.0) in the ratio 15:85, flow rate 1 mL min -1 and detection at 220 nm. The detector response was linear in the range 7.5-45 mg mL -1 . The specificity and stability indicating capability were confirmed using forced degradation under conditions of acidic, basic, oxidative and photolytic. Both the extract and synephrine shown to be susceptible to degradation in all conditions tested. Intraday precision shown RSD values lower than 1.77% and interday precision of 2.48% RSD. The average recovery accuracy of the test was 102.03%. The photodegradation kinetics was calculated for both samples, through the concentration of the drug in function of time. The degradation of synephrine SQR diluted in acetonitrile followed second-order kinetics, while the extract of Citrus aurantium showed first-order kinetics. The toxicological study of synephrine in the presence of degradation products formed was performed. The results indicate that the samples showed no mutagenic effect, but its highest concentration showed DNA damage and decreased the cell viability. Data obtained collaborate with studies in the area and can be used as input for the preparation of pharmaceutical preparations or dietary supplements that the base substance.