Effect of Ultraviolet Light Absorbers on Photostabilization of Azadirachtin-A in Solution (Part: II)

Abstract

The effect of photostabilization of azadirachtin-A (Aza-A) was examined in solutions when exposed to UV radiation, in the presence of four structurally different UV absorbers namely, p-aminobenzoic acid, 2,4-dihydroxybenzophenone, 4,4'-dihydroxybenzophenone and phenyl salicylate. The percentages of Aza-A recovered from the solutions after 6 h exposed to UV radiation in the presence and absence of UV absorbers indicated that the order of stabilization of Aza-A by these absorbers was similar to that obtained in the solid phase experiments in accordance with our previous observations. It is observed that the addition of phenyl salicylate in Aza-A (in 1:1 mole ratio) provides the excellent photostabilization of Aza-A molecule in solid phase as well as in solution among the four absorbers studied.

Octahydrogenated retinoic acid‐conjugated glycol chitosan nanoparticles as a novel carrier of azadirachtin: Synthesis, characterization, and in vitro evaluation

“…AZA is a hydrophobic pesticide with low water solubility (0.26 mg mL −1 , 20 °C) . Sunlight or UV can quickly degrade AZA because its molecules contain unstable groups, such as olefinic bond, epoxy, and enol structures . However, traditional formulations of emulsifiable AZA concentrates and dusts employ a large amount of organic reagents, which are not conducive to reducing environmental pollution, promoting food safety and human health.…”

Impact of Ultraviolet-Absorbing 2-Hydroxy-4-Quaternaryammoniumalkoxy Benzophenone Motif on Photodegradation of Disulfoton: A Case Study

“…Photodegradation of pesticides in various phases has been comprehensively studied by several groups. (Maliakal et al 2002; McGarry et al 1997; Klopffer 1977; Franko et al 2005; Katagi 2004; Ishaque et al 2013; Eyheraguibel et al 2010; Trivella and Richard 2014; Nguyen et al 2012b; Nguyen et al 2012a; Cohen et al 2001; El-Nahhal et al 2001; Margulies et al 1987;Deota et al 2002) Earlier we reported that phenyl salicylate provides e cient photoprotection of azadirachtin, a neem-based biopesticide, which nds an important place in integrated pest management (IPM), in thin-lm as well as in solution (Fig.3) (Deota et al 2002;Deota et al 2003). Recently we reported effective photostabilization of chlorpyrifos by dialkoxy benzil derivatives (Fig.4) (Patel et al 2019).…”