Research Articles

Lycium ruthenicum polysaccharides (LRP) are known to possess antioxidant effects. However, a systematic evaluation across chemical, cellular, and in vivo models have been lacking. The underlying metabolomic mechanisms also remain unexplored. This study systematically evaluated the antioxidant effects of LRP through in vitro assays, H₂O₂-induced AML12 hepatocytes, and liver tissue from mice, supplemented by untargeted metabolomic analysis of cell extracts to explore LRP’s antioxidant mechanisms. Results showed that LRP possessed significant oxygen radical absorbance capacity and potent scavenging activity against ABTS•⁺, DPPH•, and •OH radicals in vitro. In AML12 cells, LRP increased activities of antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), and glutathione reductase (GSH-Px), while effectively reducing intracellular reactive oxygen species (ROS) and malondialdehyde (MDA) levels (P<0.05). In mouse liver tissues, LRP may have slightly improved SOD and CAT levels while decreasing MDA levels (P>0.05). Furthermore, untargeted metabolomics revealed that LRP attenuated oxidative damage by modulating metabolic pathways, particularly glutathione metabolism, the tricarboxylic acid (TCA) cycle, and amino acid metabolism. These findings confirm the significant antioxidant potential of LRP, supporting its promise as a functional food ingredient.

Cotton is a vital fiber crop and major agricultural product worldwide. It was genetically engineered with Cry genes from Bacillus thuringiensis (Bt), producing insecticidal proteins called Cry (Bt) toxins. Bt cotton efficacy depends on the expression level of these toxins, which abiotic stress negatively affects. This study examined how salinity and drought stress influence Cry1Ac endotoxin levels in transgenic Bt cotton. Initially, Cry1Ac transgene presence was confirmed using polymerase chain reaction (PCR) and immunostrip assays. Genotypes were then subjected to varying levels of salinity and drought stress under controlled conditions. Bt toxin levels were quantified using a commercial ELISA kit. Results showed that increasing drought and salt stress led to a decline in Bt protein expression. Toxin concentrations in genotypes MNH-886 and Bt-121 varied across different exposure durations (days three and six) during salinity treatment. FH-113 and 3701 genotypes exhibited variable Bt protein expression in response to drought. Specifically, genotype FH-113 exhibited higher toxin levels under drought conditions (20% PEG) compared to genotype 3701. These findings indicate that genetic background influenced Bt toxin expression under drought stress. In conclusion, increasing salinity and drought result in decreasing Cry1Ac toxin levels, which may negatively impact insect resistance efficacy of Bt cotton.