Flow in the tube: crosslinking of peroxidase from agricultural waste for dye removal in microtubular reactor

Abstract

Agro-industrial waste has gained special attention as an abundatly available natural carbon source, which can be used for value-added products such as generating power, biofuel, biogas and biofertilizers production. Further application of agro-industrial waste may be as a substrate for solid state fermentation for production of antibiotics, enzymes, and phytochemicals. Isolation of enzymes from waste material as crude extracts contributes to the concept of sustainability and lowers their cost significantly. The enzyme of interest in this study was peroxidase isolated from soybean hull. Furthermore, the crude peroxidase from soybean hull was crosslinked by oxidized pectin onto the inner walls of PTFE microtubular reactor. The influence of the crosslinker concentration on the enzyme activity and crosslinking efficiency was evaluated, together with the effect of the reagents flow rate on the enzyme activity and crosslinking efficiency. Two different microtubular diameters were examined for the crude peroxidase crosslinking: 0.5 and 0.8 mm. After the immobilization, the possibility of anthraquinone dye removal by crosslinked peroxidase in the microtubular reactor was examined. The reusability of the immobilized enzyme was also evaluated in this study.

Poljoprivredni otpad predstavlja lako dostupan prirodni izvor ugljenika, koji se može koristiti za dobijanje proizvoda sa dodatom vrednošću. Poljoprivredni otpad se može koristiti kao sirovina za proizvodnju električne energije, biogorivo, biogas i proizvodnju biođubriva. Dalja primena poljoprivrednog otpada može biti kao supstrat za fermentaciju u čvrstom stanju (eng. solid state fermentation), za proizvodnju antibiotika, enzima i fitohemikalija. Izolovanje enzima iz otpadnog materijala kao sirovi ekstrakt doprinosi konceptu održivosti i značajno smanjuje cenu enzima. Enzim od interesa u ovom radu je peroksidaza izolovana iz sojinih ljuspica. Sirova peroksidaza iz sojinih ljuspica umrežena je oksidovanim pektinom na unutrašnje zidove PTFE cevnog mikroreaktor, i ispitivan je uticaj koncentracije umreživača na aktivnost enzima i efikasnost umrežavanja, kao i uticaj protoka reagensa na aktivnost enzima i efikasnost umrežavanja. Nakon toga, vršeno je ispitivanje uticaja prečnika cevnog mikroreaktora na efikasnost umrežavanja i aktivnost peroksidaze: 0,5 i 0,8 mm. Nakon imobilizacije ispitana je mogućnost uklanjanja antrahinonske boje umreženom peroksidazom u cevnom mikroreaktoru. U ovom radu je takođe je ispitivana mogućnost ponovne upotrebe imobilisanog enzima.