RESUMO
Cytotoxicity and instability are the limitations when using bioactive compounds in cosmetic and pharmacology products. This study assesses Vernonia amygdalina leaf extracts for their antityrosinase, antiamylase, and antioxidant activities. Group A extracts were obtained using an aqueous solvent system [70% (v/v) of methanol (BTL70ME), ethanol (BTL70ET), and acetone (BTL70AC)]. Group B extracts were obtained using organic solvents of varying polarities. The results displayed that all extracts exhibited antityrosinase, antiamylase, and antioxidant activities in vitro. The most potent antityrosinase activity was observed in BTL70AC, with a half-maximal inhibitory concentration (IC50) value of 20 µg/mL. BTL_Ethyl acetate and BTL70AC showed potential antiamylase activity. BTL_Isopropanol and BTL_Ethanol exhibited potential antioxidant activity, with IC50 values of 4.0 µg/mL. The total phenolic content of BTL70ME, BTL70ET, and BTL70AC was 72.29±14.14, 65.98±11.91, and 69.37±7.72 mg gallic acid/g extract, respectively. The total flavonoid content was 53.04±5.22, 44.35±13.17, and 61.74±13.17 mg quercetin/g extract, respectively. Group A extracts contained polyphenols, flavonoids, saponins, terpenoids, steroids, and cardiac glycosides. These biological properties can potentially be attributed to the types and quantities of phytochemicals present. Bioactive compounds in the extracts may exert synergistic effects in vitro by interfering with the conformational changes of tyrosinase during substrate binding. Both groups of extracts have the potential to suppress biomolecule degradation, promote antiaging and antimelasma effects, and their phytochemicals can help lower blood glucose levels in diabetes.
RESUMO
Pesticides are widely used to eradicate insects, weed species, and fungi in agriculture. The half-lives of some pesticides are relatively long and may have the dire potential to induce adverse effects when released into the soil, terrestrial and aquatic systems. To assess the potential adverse effects of pesticide pollution in the aquatic environment, zebrafish (Danio rerio) and Daphnia magna are two excellent animal models because of their transparent bodies, relatively short development processes, and well-established genetic information. Moreover, they are also suitable for performing high-throughput toxicity assays. In this study, we used both zebrafish larvae and water flea daphnia neonates as a model system to explore and compare the potential toxicity by monitoring locomotor activity. Tested animals were exposed to 12 various types of pesticides (three fungicides and 9 insecticides) for 24 h and their corresponding locomotor activities, in terms of distance traveled, burst movement, and rotation were quantified. By adapting principal component analysis (PCA) and hierarchical clustering analysis, we were able to minimize data complexity and compare pesticide toxicity based on locomotor activity for zebrafish and daphnia. Results showed distinct locomotor activity alteration patterns between zebrafish and daphnia towards pesticide exposure. The majority of pesticides tested in this study induced locomotor hypo-activity in daphnia neonates but triggered locomotor hyper-activity in zebrafish larvae. According to our PCA and clustering results, the toxicity for 12 pesticides was grouped into two major groups based on all locomotor activity endpoints collected from both zebrafish and daphnia. In conclusion, all pesticides resulted in swimming alterations in both animal models by either producing hypo-activity, hyperactivity, or other changes in swimming patterns. In addition, zebrafish and daphnia displayed distinct sensitivity and response against different pesticides, and the combinational analysis approach by using a phenomic approach to combine data collected from zebrafish and daphnia provided better resolution for toxicological assessment.