Aqueous extract from urucum (Bixa orellana L.): antimicrobial, antioxidant, and healing activity

Background: Annatto was obtained from seed B orellana (urucum) and is commonly used in food and cosmetic industries. The objective of this study was to identify the antimicrobial and antioxidant activity of the aqueous extract from urucum seeds and its skin healing potential in exposed cutaneous lesions in rats treated with the gel containing the extract. Methods: Three types of extracts from seeds were made using chloroform, sodium hydroxide, water, and estimated bixin and norbixin. In the presence of antioxidants, antibacterial was observed and then evaluated the skin healing in rats using aqueous extract. Results: Annatto dyes have been evaluated in all three extracts. When the seeds were extracted with chloroform, bixin was detected. If extraction was performed by sodium hydroxide or water, norbixin was detected. For healing use, 10% of aqueous extract was mixed in a gel base. The finding obtained from the antioxidant assay revealed that the activities of the water extract could be used as a source of polyphenolic compounds. In chloroform extract, the antioxidant was not effective because it has weak radical scavengers. With respect to antimicrobial activity, it has been observed that aqueous extract has more effect. For skin healing assay, a total of 3 study groups were tested: negative control group (gel base), positive control group (fibrinase), and test group (gel with urucum aqueous extract). After 7 days of treatment, animals treated with fibrinase had an improvement of 4.7% in total wound area when compared with the negative control while those treated with urucum aqueous extract presented an improvement of 51.55% in comparison. After 14 days, the total wound area of animals within the test group had a decrease of 94.97% when compared with the negative control (gel base) results while the control group presented an improvement of 56.58% in total wound area. These results indicate that wounds treated with urucum aqueous extract were 38.39% more efficient than fibrinase, a cream used for skin healing. Conclusions: It is possible to conclude that gel with aqueous extract is effective in skin healing in rats, being used as a phytotherapic, besides possessing antioxidant and antimicrobial activity.