Accumulation Of Malondialdehyde Content Research Articles

From tissue lesions to neurotoxicity: The devastating effects of small-sized nanoplastics on red drum Sciaenops ocellatus

Nanoplastic pollution typically exhibits more biotoxicity to marine organisms than microplastic pollution. Limited research exists on the toxic effects of small-sized nanoplastics on marine fish, especially regarding their post-exposure resilience. In this study, red drum (Sciaenops ocellatus) were exposed to small-sized polystyrene nanoplastics (30 nm, PS-NPs) for 7 days for the exposure experiments, followed by 14 days of recovery experiments. Histologically, hepatic lipid droplets and branchial epithelial liftings were the primary lesions induced by PS-NPs during both exposure and recovery periods. The inhibition of total superoxide dismutase activity and the accumulation of malondialdehyde content throughout the exposure and recovery periods. Transcriptional and metabolic regulation revealed that PS-NPs induced lipid metabolism disorders and DNA damage during the initial 1–2 days of exposure periods, followed by immune responses and neurotoxicity in the later stages (4–7 days). During the early recovery stages (2–7 days), lipid metabolism and cell cycle were activated, while in the later recovery stage (14 days), the emphasis shifted to lipid metabolism and energy metabolism. Persistent histological lesions, changes in antioxidant capacity, and fluctuations in gene and metabolite expression were observed even after 14 days of recovery periods, highlighting the severe biotoxicity of small-sized PS-NPs to marine fish. In summary, small-sized PS-NPs have severe biotoxicity, causing tissue lesions, oxidative damage, lipid metabolism disorders, DNA damage, immune responses, and neurotoxicity in red drum. This study offers valuable insights into the toxic effects and resilience of small-sized nanoplastics on marine fish.

Controlled freezing storge (CFS) maintains quality of fresh edible buds of daylily (Hemerocallis citrina) by enhancing antioxidant capacity, energy charge and unsaturation of fatty acids

Fresh buds of daylily flowers (Hemerocallis citrina) have been consumed as a nutritious vegetable, but they are very perishable after harvest. In this study, the freezing point of daylily buds with different lengths was detected and compared. Then, the buds were stored at a controlled temperature higher than the freezing point but less than 0 °C. The controlled freezing storage (CFS) set at −0.95 ± 0.25 °C remarkably maintained the edible quality and extended postharvest life of daylily buds, compared to the storage at 1 ± 0.5 °C. CFS preserved vibrant color by hindering chlorophyll reduction and fostering carotenoid accumulation. CFS notably inhibited the decline in soluble protein and the accumulation of malondialdehyde content. Additionally, CFS maintained a robust level of radical scavenging ability and energy charge, and effectively delayed the reduction in unsaturation of fatty acids. Thus, CFS can effectively mitigate the senescence progression of daylily buds in practice.

Biological Effects of Low Energy N+ Beams Implantation on Calluses of Autotetraploid Rice

Calluses of two autotetraploid rice (DPR (4) and Zijing (4)) were implanted with 30 KeV N+ beams at doses ranging from 1.0×1015 to 9.0×1015 ions cm−2. The differentiation rates of calluses, the concentration of malondialdehyde (MDA), the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), and the change of esterase (EST) spectrum were measured and analyzed on the calluses stage. The results showed that differentiation rates of calluses under 3.0×1015 ions cm−2 ((46.12±2.01)%) were higher than the other treatment groups in DPR (4), and those of Zijing (4) were similar under the doses of 1.0×1015, 3.0×1015 and 5.0×1015 ions cm−2 ((40.55±2.74), (37.77±3.04) and (34.56±2.65)%) and were higher than that of 7.0×1015 and 9.0×1015 ions cm−2. When the doses were 3.0×1015 and 5.0×1015 ions cm−2, the activities of SOD, POD and CAT were notably enhanced, and the accumulation of MDA content was markedly alleviated in the implanted calluses of two materials, as well as the activity of EST was increased by the additional isforms DPR (4). Whereas the anti-oxidative systems and enzymes spectrum of EST were destroyed seriously, the accumulation of MDA was significantly aggravated, also the differentiation rate of calluses reduced sharply and almost closed to zero when the implantation doses were 7.0×1015 and 9.0×1015 ions cm−2. It suggested that the proper dose of ion implantation effectively maintained the normal membrane structure and metabolism, and it would be also a feasible approach for autotetraploid rice to improve its genetic characteristics at calluses stage. Additionally, the differences of the radiation resistance between DPR (4) and Zijing (4) could be related to the different genotypes.