Udayabhanu Jinu, Kannan Vaitheeswari, Tiwari Manish, Natesan Geetha, Giovanni Benelli, Perumal Venkatachalam
Department of Biotechnology, Periyar University, Periyar Palkalai Nagar, Salem 636 011, Tamil Nadu, India.
Department of Plant Systems Biology, VIB, Ghent University, Gent 9000, Belgium.
J Photochem Photobiol B. 2018 Jan;178:496-504. doi: 10.1016/j.jphotobiol.2017.12.005. Epub 2017 Dec 6.
Textile industries release tonnes of harmful toxic dyes into the environment, causing severe effects on living organisms, including humans. Mosquitoes vectors spread important diseases which cause millions of human deaths worldwide. To control mosquitoes a number of synthetic mosquitocidal agents have been employed but all these pesticides pose harmful effects to human health and non-target species and also led to resistance development in treated vectors. Microbial strains are also developing resistance to the available antibiotics, this currently represents a major public health challenge. The current study is focused on the green synthesis of titanium dioxide nanoparticles (TiO NPs) using aqueous leaf extracts of Euphorbia hirta. Results suggested an efficient remedy for the above mentioned problems using TiO NPs against the dye degradation, mosquito larvae and bacterial pathogens. The fabrication of TiO NPs was confirmed by UV-visible spectroscopy, the biomolecules involved in the synthesis process were evidenced by Fourier transform infra-red spectroscopy (FT-IR), the crystalline structure was observed by using X-ray powder diffraction (XRD) analysis. Spherical shaped TiONPs were recorded using field emission scanning electron microscopy (FESEM). Energy dispersive X-ray spectroscopy (EDX) results showed the elemental composition of TiO NPs. Enhanced rate of photocatalytic dye degradation efficacy was recorded in in methylene blue (95.8%) followed by crystal violet (86.7%). Antibacterial activity assays indicated growth inhibition was highest in Staphylococcus epidermidis and Proteus vulgaris. The LC of TiO NPs and E. hirta extract on Aedes aegypti larvae were 13.2mg/l and 81.2mg/l, while on Culex quinquefasciatus they were 6.89mg/l and 46.1mg/l respectively. Overall, based on the results of the present study, the green engineered nanotitania could be considered as novel and promising photocatalytic, antibacterial, and mosquitocidal agent.
纺织工业向环境中排放大量有害有毒染料,对包括人类在内的生物造成严重影响。蚊子作为病媒传播重要疾病,在全球导致数百万人死亡。为了控制蚊子,人们使用了多种合成灭蚊剂,但所有这些杀虫剂都对人类健康和非目标物种造成有害影响,并且还导致被处理病媒产生抗药性。微生物菌株也在对现有的抗生素产生抗药性,这目前是一个重大的公共卫生挑战。当前的研究集中在利用大戟叶的水提物绿色合成二氧化钛纳米颗粒(TiO NPs)。结果表明,使用TiO NPs可以有效解决上述问题,用于染料降解、蚊子幼虫和细菌病原体。通过紫外可见光谱确认了TiO NPs的制备,通过傅里叶变换红外光谱(FT-IR)证明了参与合成过程的生物分子,通过X射线粉末衍射(XRD)分析观察了晶体结构。使用场发射扫描电子显微镜(FESEM)记录了球形的TiONPs。能量色散X射线光谱(EDX)结果显示了TiO NPs的元素组成。在亚甲基蓝(95.8%)中记录到光催化染料降解效率提高,其次是结晶紫(86.7%)。抗菌活性测定表明,表皮葡萄球菌和普通变形杆菌的生长抑制率最高。TiO NPs和大戟提取物对埃及伊蚊幼虫的LC分别为13.2mg/l和81.2mg/l,而对致倦库蚊的LC分别为6.89mg/l和46.1mg/l。总体而言,基于本研究的结果,绿色工程化的纳米二氧化钛可被视为一种新型且有前景的光催化剂、抗菌剂和灭蚊剂。