Validation of an UV spectrophotometric method for determining diffractaic acid from Usnea sp. in inclusion complexes with hydroxypropyl-β-cyclodextrin

Diffractaic acid (DA) presents several biological activities. The goal of this study was to develop and validate a UV spectrophotometric method for determining diffractaic acid in inclusion complexes with hydroxypropyl-β-cyclodextrin. Validation parameters were determined according to international guidelines for standardization. The linearity range of analytical curve was from 1 to 5 μg/mL and the regression equation: CDA = (Area - 0.0053)/0.1541 (r2 = 0.99998; n = 3). The intermediate precision indicated that the difference between the means was statistically insignificant (p < 0.05). Accuracy revealed a mean recovery percentage of diffractaic acid in inclusion complexes of 100.1 %. The method was robust and the formulation excipients did not interfere on diffractaic acid quantification. Limits of detection and quantification of diffractaic acid were 0.03 and 0.08 μg/mL, respectively. The proposed method proved to be accurate, precise and reproducible, thus being able to quantify diffractaic acid in raw material and inclusion complexes.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Hepatic toxicity caused by PLGA-microspheres containing usnic acid from the lichen C ladonia substellata (AHTI) during pregnancy in Wistar rats

ABSTRACT This study aimed to evaluate the teratogenic and hepatotoxic potential of the usnic acid encapsulated into PLGA-microspheres. In total, 12 female Wistar rats in pregnancy were randomly distributed in the control group (n= 6) that received 1.0 mL of physiological solution and treatment group (n= 6) that received 25 mg/kg of encapsulated usnic acid by oral administration. All females were euthanized at day 20 of pregnancy and their fetuses were removed and analyzed. During the pregnancy was observed a reduction in weight gain. There was no difference in serum transaminases levels analyzed as well as any difference in liver weight in both groups. The histomorphometric analysis of the liver from the treatment group revealed an increase in number of hepatocytes and a decrease in nuclear area of these cells. Moreover, no alteration was observed in cell area of hepatocytes or number of Kupffer cells. The fetuses had an increase in total number of hepatocytes and a reduction in the amount of megakaryocytes. These results show the hepatotoxic potential of usnic acid during pregnancy. However, its toxicity can be minimized by encapsulation in microspheres