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Insects are introduced as the largest group of animals in the animal kingdom. There is always a risk of disease outbreaks from insects that greatly affects people's health. Hundreds of thousands of species have been determined, whereas many others remained unnamed and unidentified. This study was carried out to identify the insect species obtained in Mo Cay Bac district, Ben Tre province, Vietnam, and identify the human pathogenic bacteria that parasitize on this insect. The study results showed that the insect carried Bacillus cereus and Micrococcus luteus, two strains of bacteria capable of causing festering wounds; whereas, the antibiotic Gentamicin (10 µg/mL) was shown to be capable of inhibiting Bacillus cereus and Micrococcus luteus. Based on morphological characteristics and DNA fragment of COII gene, the insect species has been identified as a species belonging to the Scatopsidae family, which belongs to complete metamorphosis. Its life cycle lasts 7-8 days and goes through 4 stages, including egg (1 day), larva (3-4 days), pupa (2-3 days), and adult. This insect species carry the biological characteristics of an entirely new insect species.

The study aimed to evaluate the toxic ability of the ethanol extract of Ricinus communis (L.) in Drosophila melanogaster fruit fly model. The toxicity was determined through different criteria, including the ability to cause harmful effects on second instar larvae, reproduction, growth and development, and the movement ability of fruit flies. The results showed that the ethanol extract of Ricinus communis expressed its high toxicity against 2nd instar larvae of Drosophila melanogaste with the LD50 value of 64.63 mg/mL. In addition, Ricinus communis extract reduced the growth rate, reproduction and decreased the movement ability of Drosophila melanogaster. The total flavonoid and polyphenol content of the ethanol extract of Ricinus communis were 338.26 mgQE/g extract and 160.43 mgGAE/g extract, respectively. These findings contribute to confirming the toxic properties of ethanol extract of Ricinus communis and their potential use in preventing and controlling pest.

Allelopathy is a common biological phenomenon happened when an allelopathic plant produces allelochemicals that positively or negatively affect the growth, survival, development, and reproduction of other plant species nearby in the same ecosystem. Wild plants are known as plants that are available in nature in large quantities, with the ability to reproduce quickly and many biologically active substances. Many studies have shown that wild plants are capable of synthesizing many allelochemicals. Wild plant species such as Mimosa pigra L., Leucaena leucocephala (Lamk.) de Wit., Wedelia trilobata (L.) Hitchc, Leucaena glauca Benth and Ageratum conyzoides L. are common in Vietnam and invade most cultivated land areas, affecting the productivity and growth of the surrounding crops. This review was based on the ability to inhibit weed species of some wild plants to identify the potential plants containing biologically active substances or compounds for herbicides with biosafety for agro-ecosystems.

Lipid storage droplet-2 (LSD-2) of Drosophila melanogaster is a member of the lipid storage droplet membrane surface-binding protein family. LSD-2 is detected in many specific tissues: germline precursor cells, fat body, and is associated with lipid metabolism, lipid storage, and regulation of lipid droplet transport. However, the roles of this gene in development remain unclear. To investigate these functions, we performed tissue-specific knockdown of Lsd-2 in Drosophila using the combination of GAL4/UAS system and RNAi. Here we report that the knockdown of Lsd-2 in the wing led to abnormal wing phenotype and cell death in the wing pouch of 3rd-instar larvae, suggesting an essential role of Lsd-2 in development of the Drosophila wing. This function of Lsd-2 is dependent on the transcription factor dFoxO, as dFoxO depletion suppresses cell death and the abnormal wing pattern formation induced by Lsd-2-knockdown. Furthermore, Lsd-2-knockdown up-regulated the expression of the dFoxO transcription target reaper, which constitutes a pro-apoptosis gene. This study provides the first evidence that Lsd-2-knockdown causes cell death mediated by dfoxO.

Perilipins are evolutionarily conserved from insects to mammals. Lipid storage droplet-1 (LSD-1) is a member of the lipid droplet's surface-binding protein family and counterpart to mammalian perilipin 1. The role of LSD-1 has already been reported in lipid metabolism of Drosophila. However, the function of this gene during specific tissue development is still under investigation. Here, we found that LSD-1 is expressed in the notum of the wing imaginal disc, and notum-specific knockdown of Lsd-1 by pannir-GAL4 driver leads to split thorax phenotype in adults, suggesting an essential role of LSD-1 in development of Drosophila thorax. As overexpression of JNK homolog, bsk (basket) suppresses Lsd-1 knockdown phenotype, the role of LSD-1 in thorax development was proved to be dependent on the activity of the Drosophila c-Jun N-terminal kinase (JNK). The puckered (puc) expression led to significant decrease in the JNK activity in wing discs of Lsd-1 knockdown flies. In addition, we also detected that depletion of Lsd-1 enhances apoptotic cell death in the wing notum area. Taken together, these data demonstrated that LSD-1 functions in Drosophila thorax development by regulating JNK pathway.

Although triacylglycerol, the major component for lipid storage, is essential for normal physiology, its excessive accumulation causes obesity in adipose tissue and is associated with organ dysfunction in non-adipose tissue. Here, we used Drosophila as a model for study the function of genes localized on surface of lipid droplets. In Drosophila melanogaster, the brummer (bmm) gene related to the regulation of lipid storage is homologous with human adipocyte triglyceride lipase, while perilipins are evolutionarily conserved from Drosophila to humans, the Lipid storage droplet 1 (Lsd1) is a Drosophila homolog of human perilipin 1. In the present study, we established a Drosophila model for monitoring bmm expression by using the green fluorescent protein (GFP) gene as a downstream reporter of the bmm promoter. The third instar larvae of Drosophila showed the GFP signal in all tissues observed and specifically in the salivary gland nucleus. Analyzing glucose diets on bmm promoter activity confirmed the relationship between bmm expression and obesity. Drosophila flies administered with high-glucose diets showed higher lipid contents, indicating the obesity phenotype, whereas weaker intensity of the GFP signal as well as reduced bmm mRNA expression. These results demonstrated this transgenic Drosophila model is obviously useful for screening anti-obesity agents. Lsd1’s function as a regulator of lipolysis in Drosophila has been demonstrated while its functions during development are still under investigation. In order to determine the function of Lsd1 during development, Lsd1 was knocked down in Drosophila using the GAL4-UAS system. Selective knockdown of Lsd1 in the dorsal wing disc caused an atrophied wing phenotype. The generation of reactive oxygen species in the wing pouch compartment of the Lsd1-knockdown flies was significantly higher than in the control. Immunostaining with caspase-3 antibody revealed a greater number of apoptotic cells in Lsd1-knockdown wing discs than in the control. Cell death by autophagy was induced in the knockdown flies. Moreover, cells deprived of Lsd1 showed mitochondrial expansion and decreased ATP levels. These results highlight the roles of Drosophila Lsd1 during wing development.

Perilipins are evolutionarily conserved from Drosophila to humans, the lipid storage droplet 1 (Lsd1) is a Drosophila homolog of human perilipin 1. The function of Lsd1 as a regulator of lipolysis in Drosophila has been demonstrated, as the Lsd1 mutant causes an increase of lipid droplet size. However, the functions of this gene during development are still under investigation. In order to determine the function of Lsd1 during development, Lsd1 was knocked down in Drosophila using the GAL4-UAS system. Selective knockdown of Lsd1 in the dorsal wing disc caused an atrophied wing phenotype. The generation of reactive oxygen species in the wing pouch compartment of the Lsd1-knockdown flies was significantly higher than in the control. Immunostaining with caspase-3 antibody revealed a greater number of apoptotic cells in Lsd1-knockdown wing discs than in the control. Cell death by autophagy was also induced in the knockdown flies. Moreover, cells deprived of Lsd1 showed mitochondrial expansion and decreased ATP levels. These results strongly suggest that knockdown of Lsd1 induces mitochondrial stress and the production of reactive oxygen species that result in cell death, via apoptosis and the autophagy pathway. These results highlight the roles of Drosophila Lsd1 during wing development.

Although triacylglycerol, the major component for lipid storage, is essential for normal physiology, its excessive accumulation causes obesity in adipose tissue and is associated with organ dysfunction in nonadipose tissue. Here, we focused on theDrosophilamodel to develop therapeutics for preventing obesity. The brummer (bmm) gene inDrosophila melanogasteris known to be homologous with human adipocyte triglyceride lipase, which is related to the regulation of lipid storage. We established aDrosophilamodel for monitoringbmmexpression by introducing the green fluorescent protein (GFP) gene as a downstream reporter of thebmmpromoter. The third-instar larvae ofDrosophilashowed the GFP signal in all tissues observed and specifically in the salivary gland nucleus. To confirm the relationship betweenbmmexpression and obesity, the effect of oral administration of glucose diets onbmmpromoter activity was analyzed. TheDrosophilaflies given high-glucose diets showed higher lipid contents, indicating the obesity phenotype; this was suggested by a weaker intensity of the GFP signal as well as reducedbmmmRNA expression. These results demonstrated that the transgenicDrosophilamodel established in this study is useful for screening antiobesity agents. We also report the effects of oral administration of histone deacetylase inhibitors and some vegetables on thebmmpromoter activity.