Phytotoxic and Cytotoxic Effects, Antioxidant Potentials, and Phytochemical Constituents of Stevia rebaudiana Leaves.

Stevia (Stevia rebaudiana), recognized for its low-calorie, sugar-free attributes, and various health benefits, has potential applications beyond human consumption, particularly in agriculture. This study explored the potential uses of Stevia in both agricultural and healthcare contexts by examining its plant-inhibitory, cytotoxic, and antioxidant effects. The methanolic extract of Stevia leaves was fractionated into hexane, ethyl acetate, chloroform, and water fractions. These fractions were then subjected to the bioassay analyses above and underwent identification of their chemical constituents. The results indicated that the ethyl acetate fraction demonstrated significant inhibitory effects on weed germination and growth of Beggars tick (Bidens frondosa) (100% inhibition at 1000 ppm of dose). This fraction also exhibited the highest antioxidant activity, total phenolic, and total flavonoid contents (IC50 DPPH = 18.67 µg/mL, 103.50 mg GAE/g fraction, and 410.16 mg QE/g fraction, respectively). In contrast, the chloroform fraction showed the highest cytotoxic effect (LC50 = 700.01 ppm) in the brine shrimp (Artemia salina) mortality evaluation. Pearson's correlation analysis revealed a positive correlation among plant inhibitory effects, antioxidant potentials, and phenolic/flavonoid contents of Stevia. FTIR spectra confirmed the presence of phenols and nonpolar components in the ethyl acetate and chloroform fractions. In addition, GC-MS analysis successfully identified Stevia's key constituents, including tetracontane, hexadecane, hexadecanoic acid, methyl ester in the ethyl acetate fraction, and spiro [4.5] decan-7-one and 6-hydroxy-4,4,7a-trimethyl-5,6,7,7a-tetrahydrobenzofuran-2(4H)-one in the chloroform fraction. This study underscores the potential of S. rebaudiana as a source of natural antioxidants and herbicides, offering valuable insights into its diverse applications in agriculture.

Steaming Maintains Fatty Acids, Antioxidants, and Proximate Content in Snack Bar Products from Cocoa Beans.

Chocolate products on the market are generally in the form of chocolate bars as snacks made from cocoa powder. Fat and powder are separated first through a pressing process to obtain the cocoa powder. Cocoa powder loses most of its fat content during processing. Therefore, the study aimed to determine the effect of steaming time on the cocoa bean content of fatty acids, free fatty acids, proximate levels, and antioxidant activity of snack bar products made from steamed cocoa beans. Seven steaming time intervals for cocoa beans were studied. The results showed that a longer steaming time affects the fatty acids, saturated fatty acids, antioxidants, and proximate in cocoa beans. Steaming time treatment at 45 minutes increased oleic acid, palmitic acid, and antioxidant activity. In addition, reducing free fatty acids represents a quality improvement that meets international Codex Alimentarius standards, offering a competitive advantage in the market. The food industry can adopt this steaming technique to develop snack bars and new products that are healthier and more sustainable by using steaming as an effective processing method in maintaining and increasing the nutritional value of products.