Mineral composition of Aegle marmelos (L.) Corrêa ash: Exploration of its ability to mimic the function of different metalloenzymes

Abstract

The motivation to find functional models of different metalloenzymes comes from their potential to develop better catalysts inspired by nature. Generally, metalloenzymes can activate aerial dioxygen due to the metal ions in it. Amongst the numerous metalloenzymes, catechol oxidase, and phenoxazinone synthase are the two most discussed metalloenzymes that are of interest to the research community for their ability to oxidize small organic substrates in an eco-friendly way. In this research work, Aegle marmelos (L.) Corrêa (a plant Indigenous to India) ash has been prepared as per the method mentioned in the Ayurvedic Pharmacopoeia of India (API). The ash's mineral composition has been evaluated using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The ability of Aegle marmelos (L.) Corrêa ash to mimic the function of catechol oxidase, and phenoxazinone synthase-like metalloenzymes have been explored. The results of this study confirm that Aegle marmelos (L.) Corrêa ash can as a catalyst for promoting the aerobic oxidation of the organic substrates 3,5-di-tert-butylcatechol (3,5-DTBC) and o-aminophenol (OAPH) to their corresponding chromophores, which are the functions of catechol oxidase and phenoxazinone synthase metalloenzymes respectively. The average values of Vmax and KM-like kinetic parameters for catechol oxidase mimicking activity of ash are (3.4826 ± 0.0896) x 10-5 M S-1 and (512.9146 ± 13.7268) x 10-5 M, respectively. Similarly, the average values of Vmax and KM-like kinetic parameters for phenoxazinone synthase mimicking activity of ash are (1.8871 ± 0.0461) x 10-5 M S-1 and (1823.0084 ± 25.3384) x 10-5 M, respectively.