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Background: Insects encounter various environmental stresses, in response to which they generate reactive oxygen species (ROS). Superoxide dismutase (SOD) is an antioxidant metalloenzyme that scavenges superoxide radicals to prevent oxidative damage. Objective: To investigate expressions of SODs under oxidative stress in Tenebrio molitor. Methods: Here, we investigated the transcriptional expression of SODs by pesticide and heavy metals in Tenebrio moltior. First, we searched an RNA-Seq database for T. molitor SOD (TmSOD) genes and identified two SOD isoforms (TmSOD1-iso1 and iso2). We examined their activities under developmental stage, tissue-specific, and various types (pesticide and heavy metal) of oxidative stress by using qPCR. Results: Our results revealed two novel forms of TmSODs. These TmSODs had a copper/zinc superoxide dismutase domain, active site, Cu2+ binding site, Zn2+ binding site, E-class dimer interface, and P-class dimer interface. TmSODs (TmSOD1-iso1 and iso2) were expressed in diverse developmental phases and tissues. Pesticides and heavy metals caused an upregulation of these TmSODs. Conclusion: Our findings suggest that the two TmSODs have different functions in T. molitor, providing insights into the detoxification ability of T. molitor. [ABSTRACT FROM AUTHOR]

Human advancements in agriculture, urbanization, and industrialization have led to various forms of environmental pollution, including heavy metal pollution. Insects, as highly adaptable organisms, can survive under various environmental stresses, which induce oxidative damage and impair antioxidant systems. To investigate the peroxidase (POX) family in Tenebrio molitor, we characterized two POXs, namely TmPOX-iso1 and TmPOX-iso2. The full-length cDNA sequences of TmPox-iso1 and TmPox-iso2 respectively consisted of an open reading frame of 1815 bp encoding 605 amino acids and an open reading frame of 2229 bp encoding 743 amino acids. TmPOX-iso1 and TmPOX-iso2 homologs were found in five distinct insect orders. In the phylogenetic tree analysis, TmPOX-iso1 was clustered with the predicted POX protein of T. castaneum, and TmPOX-iso2 was clustered with the POX precursor protein of T. castaneum. During development, the highest expression level of TmPox-iso1 was observed in the pre-pupal stage, while that of TmPox-iso2 expression were observed in the pre-pupal and 4-day pupal stages. TmPox-iso1 was primarily expressed in the early and late larval gut, while TmPox-iso2 mRNA expression was higher in the fat bodies and Malpighian tubules. In response to cadmium chloride treatment, TmPox-iso1 expression increased at 3 hours and then declined until 24 hours, while in the zinc chloride-treated group, TmPox-iso1 expression peaked 24 hours after the treatment. Both treated groups showed increases in TmPox-iso2 expression 24 hours after the treatments. [ABSTRACT FROM AUTHOR]

Seaweed beds are productive marine ecosystems; they provide habitat and serve as spawning, breeding, and feeding sites for fish and shellfish. Seaweed beds are declining with environmental change and pollution. In affected areas, including "urchin barrens" and those affected by "whitening events," coralline algae appear, preventing the attachment of seaweed spores to the substrate. Many methods have been used to restore seaweed beds, such as those employing artificial reefs, seaweed ropes, spore bags, and transplanted cultures. However, such efforts are insufficient to overcome the disappearance of seaweed beds from coastal areas. This study examined the use of a new technique that involves encapsulating seaweed zygotes with polysaccharide-like alginates to improve their attachment using the brown alga Sargassum fulvellum, which plays an important role in seaweed forests. We tested the efficacy of encapsulated zygotes using polyvinyl chloride (PVC) panels and concrete bricks in the sea. In the laboratory, the germination percentage of encapsulated Sargassum zygotes was 70% ± 1.6%, similar to the rate of unencapsulated zygotes. In the field experiment, PVC panels and concrete bricks were coated with encapsulated and unencapsulated zygotes; the germination density and growth rates of encapsulated zygotes were 4 (p < 0.001) and 7 times (p < 0.016) greater, respectively, than those of unencapsulated zygotes. The germination density and growth rate of encapsulated zygotes on concrete bricks were also greater. Therefore, encapsulation should increase the attachment of seaweed spores in marine environments. [ABSTRACT FROM AUTHOR]

The algal cell immobilization is a commonly used technique for treatment of waste water, production of useful metabolites and management of stock culture. However, control over the size of immobilized droplets, the population of microbes, and production rate in current techniques need to be improved. Here, we use drop-on-demand inkjet printing to immobilize spores of the alga Ecklonia cava within alginate microparticles for the first time. Microparticles with immobilized spores were generated by printing alginate-spore suspensions into a calcium chloride solution. We demonstrate that the inkjet technique can control the number of spores in an ejected droplet in the range of 0.23 to 1.87 by varying spore densities in bioink. After the printing-based spore encapsulation, we observe initial sprouting and continuous growth of thallus until 45 days of culture. Our study suggest that inkjet printing has a great potential to immobilize algae, and that the ability to control the number of encapsulated spores and their microenvironments can facilitate research into microscopic interactions of encapsulated spores. [ABSTRACT FROM AUTHOR]