We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Insights into the response mechanisms of Tetradesmus obliquus to aged polylactic acid and tetracycline exposure via transcriptome analysis and physiological evaluations
AI summary Read the abstract
Researchers studied how a freshwater green alga responds to aged biodegradable polylactic acid microplastics combined with the antibiotic tetracycline. They found that aged microplastics were more toxic than new ones, and when combined with the antibiotic, caused greater oxidative stress and disrupted photosynthesis at the genetic level. The findings suggest that as biodegradable plastics break down in the environment, they may become more harmful and can amplify the effects of other pollutants.
Microplastics (MPs) and antibiotics, identified as emerging pollutants, are extensively prevalent in aquatic environments and display prolonged durability. Unlike conventional plastics, biodegradable plastics are more susceptible to decomposition in the environment, resulting in the generation of microplastics and posing potential risks to the aquatic ecosystems. In this study, we assessed growth inhibition, chlorophyll a content, malondialdehyde content (MDA), and antioxidant enzyme activities. These measurements were integrated with transcriptome analysis to explore the response mechanisms of virgin and aged polylactic acid (vPLA and aPLA) and tetracycline (TC) following 14-day exposure to Tetradesmus obliquus, either individually or in combination. The findings indicated that exposure to vPLA did not significantly impact the growth of T. obliquus. Conversely, aPLA demonstrated growth-promoting effects on T. obliquus, particularly in the latter incubation stages. Moreover, a 14-day exposure significantly increased the chlorophyll a content and the activities of superoxide dismutase (SOD), catalase glutathione (CAT) and glutathione S-transferase (GST) within the algal cells. Apart from 1 mg L, the TC concentrations of 2.5, 5.0, and 10 mg L exhibited significant toxic effects on T. obliquus, including growth inhibition, decreased chlorophyll a content, elevated activities of SOD, CAT, and GST, and increased MDA levels. Exposure to a combination of 300 mg L aPLA and 5.0 mg L TC, compared to solely 5 mg L TC, demonstrated a notable reduction in TC toxicity to T. obliquus in the presence of aPLA. This was indicated by elevated algal cell density and chlorophyll a content, as well as a decrease in MDA content. Transcriptome analysis indicated an enrichment of differentially expressed genes (DEGs) in pathways linked to porphyrin metabolism, photosynthesis, carbon fixation, and metabolism within the aPLA + TC combined exposure. The study aid in expanding our knowledge of the potential ecological risks posed by biodegradable plastics and accompanying pollutants in aquatic environments.
More Papers Like This
Complex co-contaminant responses of Chlorella sp. and its phycosphere microbiota under co-exposure to PET microfibers and oxytetracycline
AI summary Read the abstract
Researchers exposed green algae and their surrounding microbial community to both PET microplastic fibers and an antibiotic, finding that combined exposure caused far greater genetic stress than either pollutant alone — with over 12,000 genes disrupted. The study also found that microplastic fibers promoted the spread of antibiotic resistance genes in the microbial community, raising ecological concerns about co-occurring plastic and drug pollution in waterways.
Ecotoxicological impact of virgin and environmental microplastics leachate on Chlorella vulgaris: Synergistic microbial-pollutant drivers cripple photosynthesis
AI summary Read the abstract
Researchers compared the toxic effects of leachate from new versus environmentally weathered microplastics on a common green algae species. They found that weathered microplastics were up to 3.4 times more toxic, severely disrupting photosynthesis and introducing hundreds of bacterial species and pollutants that compounded the damage. The findings highlight that microplastics become significantly more dangerous as they age in the environment.
Accelerated aging behavior of degradable and non-degradable microplastics via advanced oxidation and their adsorption characteristics towards tetracycline
AI summary Read the abstract
Researchers compared how biodegradable polylactic acid and conventional polystyrene microplastics age when exposed to advanced oxidation processes, and how aging changes their ability to adsorb the antibiotic tetracycline. They found that polylactic acid degraded more quickly and developed more surface changes during aging, leading to increased antibiotic adsorption. The findings suggest that as biodegradable plastics break down in the environment, they may become more effective at concentrating and transporting chemical contaminants.
Integrating transcriptomics and biochemical analysis to understand the interactive mechanisms of the coexisting exposure of nanoplastics and erythromycin on Chlorella pyrenoidosa
AI summary Read the abstract
Researchers used transcriptomics and biochemical analysis to study how nanoplastics and the antibiotic erythromycin interact when both are present in water with the green alga Chlorella pyrenoidosa. They found that the combined toxicity was dynamic, shifting from synergistic to antagonistic effects depending on nanoplastic concentration and exposure duration. The study indicates that co-exposure disrupts algal cell membranes, induces oxidative stress, and reduces photosynthetic efficiency.
The combined effects of aging polylactic acid microplastics and TCPP on the byssus genes of the mussel Mytilus coruscus
AI summary Read the abstract
Researchers exposed mussels to polylactic acid microplastics, both new and aged, combined with a flame retardant chemical for 14 days and measured effects on byssus thread gene expression. They found that aged biodegradable microplastics and the flame retardant each suppressed genes related to the adhesive byssal plaque, and their combined effects worsened with increasing concentration. The study emphasizes that even biodegradable plastics become more ecotoxic as they age in marine environments.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.