Facile green synthesis of zinc oxide nanoparticles using Ulva lactuca seaweed extract and its evaluation of photocatalytic, antibiofilm and larvicidal activity: impact on mosquito morphology and biofilm architecture

Publication date: Available online 7 November 2017
Source:Journal of Photochemistry and Photobiology B: Biology
Author(s): Ramachandran Ishwarya, Baskaralingam Vaseeharan, Subramanian Kalyani, Balan Banumathi, Marimuthu Govindarajan, Naiyf S. Alharbi, Shine Kadaikunnan, Mohammed N. Al-anbr, Jamal M. Khaled, Giovanni Benelli
The bioactivity of semiconductor nanocomplexes has been poorly studied in the field of pesticide science. In this research, the synthesis of zinc nanoparticles was accomplished through new effortless green chemistry process using the Ulva lactuca seaweed extract as a reducing and capping agent. The production of U. lactuca-fabricated ZnO nanoparticles (Ul-ZnO Nps) was characterized by powder X-ray diffraction (XRD), UV–visible and Fourier transform infrared (FTIR) spectroscopy, as well as transmission electron microscopy (TEM). The U. lactuca-fabricated ZnO NPs were tested for their photodegradative action against organic dyes, antibiofilm and larvicidal activities. The UV visible absorbance spectrum of Ul-ZnO Nps exhibits the absorbance band at 325nm and TEM image shows average crystallite sizes of nanoparticles at 10–50nm. Methylene blue (MB) dye was efficiently corrupted under sunlight in the presence of Ul-ZnO Nps. Excellent bactericidal activity was shown by the Ul-ZnO Nps on Gram positive (Bacillus licheniformis and Bacillus pumilis) and Gram negative (Escherichia coli, Proteus vulgaris) bacteria. High antibiofilm activity was noted under both dark and sunlight condition. The impact of a single treatment with Ul-ZnO Nps on biofilm architecture was also analyzed by confocal laser scanning microscopy (CLSM) on both Gram positive and Gram negative bacteria. Moreover, Ul-ZnO NPs led to 100% mortality of Aedes aegypti fourth instar larvae at the concentration of 50μg/ml within 24h. The effects of ZnO nanoparticle-based treatment on mosquito larval morphology and histology were also monitored. Overall, based on our results, we believe that the synthesis of multifunctional Ul-ZnO Nps using widely obtaining seaweed products can be promoted as a potential eco-friendly option to chemical methods currently used for nanosynthesis of antimicrobials and mosquito larvicides.

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