Abstract：
BACKGROUND: Mosquitoes are widespread globally and have contributed to transmitting pathogens to humans and the burden of vector-borne diseases. They are effectively controlled at their larval stages by biocontrol agents. Unravelling natural sources for microbial agents can lead us to novel potential candidates for managing mosquito-borne diseases. In the present study, an attempt was made to isolate a novel bacterium from the field-collected agricultural soil for larvicidal activity and promising bacterial metabolites for human healthcare.
RESULTS: Field-collected soil samples from the Union territory of Puducherry, India, have been used as the source of bacteria. Isolate VCRC B655 belonging to the genus Lysinibacillus was identified by 16S rRNA gene sequencing and exhibited promising larvicidal activity against different mosquito species, including Culex (Cx.) quinquefasciatus, Anopheles (An.) stephensi, and Aedes (Ae.) aegypti. The lethal concentration (LC) of Lysinibacillus sp. VCRCB655 was observed to be high for Cx. quiquefasciatus: LC50 at 0.047 mg/l, LC90 at 0.086 mg/l, followed by An. stephensi and Ae. aegypti (LC50: 0.6952 mg/l and 0.795 mg/l) respectively. Additionally, metabolic profiling of the culture supernatant was carried out through Gas chromatography and Mass spectrophotometry (GC/MS) and identified 15 major secondary metabolites of different metabolic classes. Diketopiperazine (DKPs), notably pyro lo [1, 2-a] pyrazine1, 4-dione, are the abundant compounds reported for antioxidant activity, and an insecticide compound benzeneacetic acid was also identified.
CONCLUSIONS: A new bacterial isolate, Lysinibacillus sp. VCRC B655 has been identified with significant larvicidal activity against mosquito larvae with no observed in non-target organisms. GC-MS analysis revealed diverse bioactive compounds with substantial biological applications. In conclusion, Lysinibacillus sp. VCRC B655 showed promise as an alternative biocontrol agent for mosquito vector control, with additional biological applications further enhancing its significance.
RESULTS: Field-collected soil samples from the Union territory of Puducherry, India, have been used as the source of bacteria. Isolate VCRC B655 belonging to the genus Lysinibacillus was identified by 16S rRNA gene sequencing and exhibited promising larvicidal activity against different mosquito species, including Culex (Cx.) quinquefasciatus, Anopheles (An.) stephensi, and Aedes (Ae.) aegypti. The lethal concentration (LC) of Lysinibacillus sp. VCRCB655 was observed to be high for Cx. quiquefasciatus: LC50 at 0.047 mg/l, LC90 at 0.086 mg/l, followed by An. stephensi and Ae. aegypti (LC50: 0.6952 mg/l and 0.795 mg/l) respectively. Additionally, metabolic profiling of the culture supernatant was carried out through Gas chromatography and Mass spectrophotometry (GC/MS) and identified 15 major secondary metabolites of different metabolic classes. Diketopiperazine (DKPs), notably pyro lo [1, 2-a] pyrazine1, 4-dione, are the abundant compounds reported for antioxidant activity, and an insecticide compound benzeneacetic acid was also identified.
CONCLUSIONS: A new bacterial isolate, Lysinibacillus sp. VCRC B655 has been identified with significant larvicidal activity against mosquito larvae with no observed in non-target organisms. GC-MS analysis revealed diverse bioactive compounds with substantial biological applications. In conclusion, Lysinibacillus sp. VCRC B655 showed promise as an alternative biocontrol agent for mosquito vector control, with additional biological applications further enhancing its significance.
摘要：
背景：蚊子在全球范围内广泛传播，并导致将病原体传播给人类和媒介传播疾病的负担。它们在幼虫阶段被生物防治剂有效地控制。解开微生物制剂的天然来源可以使我们成为管理蚊媒疾病的新潜在候选人。在本研究中,尝试从田间收集的农业土壤中分离出一种新型细菌，以具有杀幼虫活性和有希望的细菌代谢产物，用于人类保健。
结果：从Puducherry联盟领土实地收集的土壤样品，印度,被用作细菌的来源。通过16SrRNA基因测序鉴定了属于Lysinibacillus属的VCRCB655分离株，并表现出对不同蚊子的有希望的杀幼虫活性，包括Culex(Cx.)quinquefasciatus，按蚊（An。)Stephensi,和伊蚊（Ae.)埃及伊蚊。溶血芽孢杆菌的致死浓度（LC）。观察到VCRCB655对于Cx是高的。Quiquefasciatus：LC50为0.047mg/l，0.086mg/l的LC90，其次是一个。Stephensi和Ae.埃及伊蚊(LC50:0.6952mg/l和0.795mg/l)。此外,通过气相色谱和质谱(GC/MS)对培养上清液进行代谢分析,并鉴定出不同代谢类别的15种主要次级代谢物。二酮哌嗪（DKP），特别是pyrolo[1，2-a]吡嗪1，4-二酮，是据报道具有抗氧化活性的丰富化合物，并鉴定出一种杀虫剂化合物苯乙酸。
结论：一种新的细菌分离株，溶血芽孢杆菌。已鉴定出VCRCB655对蚊子幼虫具有显着的杀幼虫活性，在非目标生物中未观察到。GC-MS分析揭示了具有大量生物学应用的多种生物活性化合物。总之,溶血芽孢杆菌。VCRCB655显示出有望作为蚊子媒介控制的替代生物防治剂，随着额外的生物应用进一步增强其意义。
结果：从Puducherry联盟领土实地收集的土壤样品，印度,被用作细菌的来源。通过16SrRNA基因测序鉴定了属于Lysinibacillus属的VCRCB655分离株，并表现出对不同蚊子的有希望的杀幼虫活性，包括Culex(Cx.)quinquefasciatus，按蚊（An。)Stephensi,和伊蚊（Ae.)埃及伊蚊。溶血芽孢杆菌的致死浓度（LC）。观察到VCRCB655对于Cx是高的。Quiquefasciatus：LC50为0.047mg/l，0.086mg/l的LC90，其次是一个。Stephensi和Ae.埃及伊蚊(LC50:0.6952mg/l和0.795mg/l)。此外,通过气相色谱和质谱(GC/MS)对培养上清液进行代谢分析,并鉴定出不同代谢类别的15种主要次级代谢物。二酮哌嗪（DKP），特别是pyrolo[1，2-a]吡嗪1，4-二酮，是据报道具有抗氧化活性的丰富化合物，并鉴定出一种杀虫剂化合物苯乙酸。
结论：一种新的细菌分离株，溶血芽孢杆菌。已鉴定出VCRCB655对蚊子幼虫具有显着的杀幼虫活性，在非目标生物中未观察到。GC-MS分析揭示了具有大量生物学应用的多种生物活性化合物。总之,溶血芽孢杆菌。VCRCB655显示出有望作为蚊子媒介控制的替代生物防治剂，随着额外的生物应用进一步增强其意义。
