Phytochemical and biological evaluation of metabolites produced by alginate-immobilized Bionts isolated from the lichen Cladonia substellata vain.

In this work, new biotechnological procedures have been optimized on the basis of immobilization in alginate of bionts isolated from the lichen C. substellata. From these immobilizates, soluble and biologically active phenolics can be obtained. During bionts-immobilization, stictic, norstictic and usnic acids were secreted to the medium. The amount produced of each of them differed depending on the immobilization time, the precursor supplied and the type of biont used. Greater amounts of stictic acid were detected and maintained over time in all bioreactors. The opposite occurs in non-immobilized thallus. Virtually, all lichen phenols exhibit antioxidant activity to a greater or lesser degree, so that the antioxidant capacity of stictic acid (82.13% oxidation inhibition) was tested. The soluble extract of immobilized algae co-incubated in sodium acetate with fungal hyphae contained carbohydrates and exhibited a potent antioxidant capacity after 13 days of immobilization (94.87%). Therefore, attempts have been made to relate both parameters. On the other hand, the growth of Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae was inhibited by phenolic compounds produced by immobilizates, although the organic extract of the whole lichen showed the highest activity due to a possible synergy with other indeterminate compounds. Thus, C. substellata immobilized bionts are a potential source of different natural antioxidant and antimicrobial compounds.

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

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.

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.

Açäo de alcalóides indólicos sobre o sistema nervoso / Action of indole alkaloids on nervous system

Das cascas do tronco da Tabernaemontana fuchsiaefolia, foi isolada uma mistura de alcalóides indólicos que apresentaram atividade depressora sobre o sistema nervoso central (SNC) e estimulaçäo das contraçöes espontâneas em útero isolado de rata

Alcalóides indólicos de açäo endócrina potencial / Indole alkaloids of potential endocrine effect

Os alcalóides indólicos isolados das folhas de Ervatamia coronaria em útero isolado de rata, estimularam as contraçöes espontâneas seguidas de diminuiçäo gradativa da amplitude. Testes realizados com um dos alcalóides isolados da mistura, a 10-metoxi-11-hidroxiheyneanina, mostraram uma única contraçäo de grande amplitude. No teste agudo de toxicidade geral (hipocrático) da mistura de alcalóides totais näo foi observada nenhuma açäo