ABSTRACT
Objective:To investigate the effect of iron nanoparticles and melatonin on yield and quality of <italic>Fritillaria przewalskii</italic> and provide technical support for its domesticated cultivation. Method:Hundred grain weight was measured by conventional method；alkaloid content was detected according to protocols of the edition of 2020 <italic>Chinese Pharmacopoeia</italic>，chlorophyll，hydrogen peroxide，malondialdehyde，superoxide dismutase （SOD），peroxidase （POD） and catalase （CAT） were detected by spectrophotometric analysis，auxins，cytokinins，gibberellins，salicylic acid，jasmonic acid and abscisic acid were detected by ultra performance liquid chromatography tandem mass spectrometry analysis. Result:Zero-valent iron nanoparticles and melatonin significantly increased the hundred grain weight without affecting the quality. The effect of the two treatments on physiological and biochemical indexes in different stages were quite different，but the effects on content of endogenous hormones were basically the same. Correlation analysis showed that hundred grain weight was negatively correlated with malondialdehyde content，SOD activity and jasmonic acid content，but positively correlated with POD activity，salicylic acid content，gibberellins content，auxin content and abscisic acid content. The two treatments were separated effectively by principal component analysis，indicating that there were some differences in the mechanisms of growth promoting. The treatment of zero-valent iron nanoparticles mainly affected auxins，salicylic acid and abscisic acid. The treatment of melatonin mainly affected SOD，malondialdehyde and gibberellins. Conclusion:Zero-valent iron nanoparticles and melatonin can be used as a simple and practical technology to improve the stress resistance and yields of <italic>F. przewalskii</italic> in domesticated cultivation conditions.
ABSTRACT
The present study evaluates the effect of integrated nano-bio hybrid system involving nanoscale zero-valent iron (nFe0) and yeast Candida sp. SMN04 on degradation of cefdinir in aqueous medium. The nanoparticle was chemically synthesised and characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), EDAX analysis and particle size analyser. Nano-bio hybrid system was prepared using optimal concentration (50 mg/mL) of chemically synthesized nFe0, which were coated on the surface of yeast cells without causing any lethal effects to the cell. The survival and viability of the yeast cells were monitored by AFM and SEM images. Cefdinir (250 mg/L) degradation was studied, in both, the individual and hybrid system. The nano-bio hybrid system showed more effective cefdinir degradation compared to native yeast cell and nano zero-valent iron solely. The adherence of nanoparticles on the surface of the yeast cells increased the permeability of the cell membrane, thereby enhancing the entry of cefdinir into the cell. The kinetic data showed the half-life of cefdinir as 1.34 days for nano-bio hybrid system, 3.99 days for nFe0 and 2.96 days for native yeast, Candida sp. SMN04 confirming that nano-bio hybrid system reduced the half-life to less than half of the time taken by the yeast alone. This study signifies the potential efficacy of the nano-bio hybrid system to serve as an effective remedial tool for the treatment of pharmaceutical wastewater.