Alga marinha Gracilaria birdiae: avaliação de atividades biológicas in vivo e in vitro e utilização em preparações culinárias

Abstract

The red seaweed Gracilaria birdiae (GB) is cultivated and ingested as food in Northeast Brazil. However, the economic potential of this algae is little explored. To enable both the direct consumption and diversification of GB products, it is necessary to evaluate its effects in vivo. Therefore, the aim of this research was to evaluate, in Mus musculus mice, GB's antioxidant action, protective effect against harmful agent, and the potential acute and chronic toxicity. GB's culinary use was also a part of this study. In order to do that, the animals were divided in three groups, being one the control group and the other two the experimental groups (which had GB added to their food). During the analysis it was observed that GB was able to reduce weight gain and blood glucose level in mice. Besides that, it increased the antioxidant capacity and the levels of glutathione reductase and catalase in the treated animals when compared with the animals of the control group. Some mice also received carbon tetrachloride (CCl4). In this case, histological, enzymatic and antioxidant tests showed GB may be able to protect the animals from this toxic agent. In addition, the GB aqueous extract inhibited 50% differentiation of 3T3-L1 cells into adipocytes. When evaluating the chronic and acute toxicity of this seaweed, it was observed that the animals that were submitted to 90 days of treatment with GB showed a weight loss, lower glycemia and lower levels of triglycerides, and no morphological changes were observed. Regarding the use of GB in culinary, several preparations were tested through a sensorial evaluating of which results showed satisfactory acceptance by the participants. The results of this study suggest that GB helps to reduce weight gain, decrease glycemia and blood triglycerides, increase antioxidant capacity and the levels of glutathione reductase and catalase, as well as the protective effect against CCl4 in mice. These findings suggest that GB has health protective action in vivo and do not show toxicity to mice, which highlights Gracilaria birdiae's health benefits and the possibility of its use for human consumption.