Introduction/Objective: The ethanolic pretreatment of stevia leaves is considered ecologically favorable and increases its yield, purity level, and sensory profile of sweeteners. We investigated the by-product generated so that we can provide a viable and applicable destination to effectively contribute to the production and industrial chain of stevia sweeteners. Recently, an antioxidant and antidiabetic fraction was obtained through stevia methanolic extraction. However, this process is costly, has a low yield, and is non-green. In this study, we got an antioxidant fraction of stevia from its pretreatment by-product, the ethanolic extract, characterized its bioactive compounds – mainly phenolic acids and flavonoids – and evaluated its antidiabetic and antilipid capacity. Methods: The ethanolic extract was fractionated, then the ethyl acetate fraction was microencapsulated. Physicochemical, Mass Spectrometry (UHPLC/MS-MS), scanning electron microscopy, microencapsulation efficiency, and antioxidant capacity analyses were carried out. The antioxidant capacity was evaluated. Antihyperglycemic capacity was assessed by inhibition of α-glucosidase and α-amylase. For antilipid potential, inhibition of pancreatic lipase was measured. Results: Antioxidant potential was observed mainly in the fraction. Microencapsulation improved the stability of the fraction. Mass spectrometry allowed comparison with phenolic and flavonoid compounds from the methanolic and ethanolic fractions of the by-product. Many compounds were coincident, which may explain the similar antioxidant capacity found. The samples showed more than 90% inhibition of alpha-glucosidase, which may indicate potential antidiabetic activity. All samples showed inhibition of the pancreatic lipase enzyme higher than 80%, reaching 91.05% for the free fraction. Conclusion: This study represented the recovery of a by-product and showed that this antioxidant fraction deserves further investigation for its bioactive potential, especially antioxidant, antidiabetic, and anti-lipid.

Important arboviruses for public health such as Dengue, Zika, and Chikungunya are transmitted by mosquito vectors, primarily Aedes aegypti and Aedes albopictus. The control of populations of these mosquitoes can be carried out by mechanical, chemical, and biological control. In view of the environmental impacts caused by synthetic chemical insecticides, the search for botanical larvicides with larvicidal potential has intensified. The objective of this work is to investigate the occurrence of acetylcholinesterase inhibition and histopathological alterations in Aedes aegypti and Aedes albopictus submitted to treatment with the ethanolic extract of the leaves of Acmella oleracea as possible mechanisms of larvicidal action. Larvae of Aedes aegypti and Aedes albopictus were exposed to treatment with the ethanolic extract of Acmella oleracea for an exposure period of 24 hours. After this time, larval mortality was recorded, and the larvae were separated in order to investigate the mechanisms of action. The ethanolic extract of Acmella oleracea had an LC50 of 29.15 µg.mL−1 and 16.00 µg.mL−1 against Aedes aegypti and Aedes albopictus, respectively. Significant reductions in acetylcholinesterase activity were observed in larvae treated with the ethanolic extract of Acmella oleracea, as well as histopathological changes in the midgut of treated larvae, including loss of integrity of the intestinal epithelium, vacuolation of the cell cytoplasm, and disruption of the peritrophic matrix. These results suggest that that the mechanism of action of the ethanolic extract of Acmella oleracea against Aedes larvae includes the potential to inhibit acetylcholinesterase and cause histopathological alterations in the midgut.