Seasonal and altitudinal variation in oil yield chemical composition and biosynthesis of nanoparticles mediated by Cymbopogon flexuosus essential oil and evaluation of its bioactivities and photocatalytic assessment

Abstract

newline xvi newlineABSTRACT newlineNanotechnology has become one of the most promising technologies applied in all fields of Science. Biofabrication of metallic nanoparticles mediated from plants has gained attention due to their trouble-free, fast and eco-friendly nature. In the present study, a very simple rapid, cost-effective, and environmental friendly pathway was followed for the fabrication of gold, silver, magnesium and zinc oxide nanoparticles using essential oil Cymbopogon flexuosus collected from different altitudes. The main focus of the research is to evaluate the effect of seasonal and altitudinal variation on the bioactivities and photocatalytic efficiency of fabricated nanoparticles from different altitudes (Palampur, Dehradun and Khizrabad). Phyto-constituents were analyzed by GC-MS. Phytochemical analysis of essential oil of C. flexuosus showed the presence of different phytoconstituents in variable amounts in the essential oil collected from different altitudes in different seasons. newlineBiofabricated gold, silver, Mg and ZnO nanoparticles were characterized by UV-visible spectroscopy, XRD, FTIR, and TEM analysis. UV-visible spectrum of AuNPs from different altitudes (Palampur, Khizrabad and Dehradun) showed absorption peaks at 557nm, 559nm and 559nm, respectively of summer season whereas, 559nm, 558nm and 559nm of winter season. AgNPs showed absorption peaks at 429nm, 416nm and 411nm of summer season whereas, 410nm, 413nm and 426nm, respectively of winter season. MgNPs showed maximum absorption peaks at 306nm, 280nm and 274nm of summer season while 303nm, 285nm and 264nm of winter season. ZnO NPs showed absorption maxima at 361nm, 359nm and 363nm of summer season whereas, 363nm, 360nm and 365nm of winter season. The presence of various functional groups in the fabricated Au, Ag, Mg and ZnO nanoparticles of different altitudes in both seasons were confirmed by FTIR spectroscopy. The crystalline nature of synthesized nanoparticles was established from the XRD analysis. Average crystalline size of nanoparticles evaluated from TEM revealed that size range of gold nanoparticles was 10-32 nm. Silver nanoparticles have average size range between 7-50 nm, magnesium nanoparticles have average size range between 8-90 nm whereas, average size of ZnO nanoparticles ranges between 10-70 nm in size. Gold, magnesium, silver and zinc-oxide nanoparticles were subjected for evaluation of antibacterial, antifungal and photocatalytic assessment. The antibacterial activities of synthesized nanoparticles from essential oil of C. flexuosus of different sites in both seasons were checked newlinexvii newlineagainst S. aureus and E. coli. Gold nanoparticles showed maximum antibacterial activity against both the bacteria s. Antifungal activity of fabricated nanoparticles was evaluated against Fusarium oxysporum. Maximum antifungal activity of synthesized Au nanoparticles was given by AuS1 and AuS3. For silver nanoparticles AgS2 showed highest %age inhibition against F. oxysporum. For magnesium nanoparticles highest activity was shown by MgS3 whereas, for ZnO nanoparticles highest activity was shown by ZnOS3. Photocatalytic degradation was carried out against methylene blue (MB) Dye. Maximum photocatalytic degradation from all the fabricated nanoparticles, ZnO nanoparticles showed maximum photocatalytic degradation i.e. 93% from site-II of winter season. newlineThe current research reported an effortless and efficient approach for the fabrication of gold, magnesium, silver and ZnO nanoparticles and seasonal and altitudinal variation in the fabrication of nanoparticles as well as in the antibacterial, antifungal and photocatalytic efficiency which may be helpful for medicine and drug manufacturing and also for removal of organic pollutants from waste water.