Investigation of gaseous ozone as an anti‐fungal fumigant for stored wheat

Abstract

In this study, gaseous ozone was used as a fungicide to preserve stored wheat. The following operating parameters were investigated for their effects on the fungicidal efficacy of ozone: (1) the applied ozone dose; (2) ozonation time; (3) water activity of the wheat; and (4) temperature of the wheat. The effect of ozonation on germination of the wheat was also studied. Experimental results revealed that gaseous ozone was very effective in the inactivation of fungi associated with the wheat. Within 5 min of ozonation, 96.9% of the fungal spores were inactivated by applying 0.33 mg of ozone (g wheat) −1 min −1 . It was also found that increases in both water activity and temperature of the wheat enhanced the fungicidal efficacy of ozone. In addition, results of this study indicated that the inactivation processes could be controlled by simply monitoring the ozone exiting from the reactor and, consequently, the time-consuming microbial examination processes could be avoided. This finding would make the application of ozone in the preservation of cereal grains easier, simpler, and more cost-effective. It was also found that although the applied ozone doses above certain thresholds may reduce the germination of wheat, the inactivation of fungi could be achieved using applied ozone doses far below those thresholds.

Ozone as fungicide in rice grains

“…(not object of this study). This occurred due to its large antimicrobial spectrum, which makes it also efficient in the control of bacteria and protozoa (Akbas & Ozdemir, 2008;Wu et al, 2006). Table 4.…”

“…It is known that, in agricultural products, the ozone gas inhibits or delays the development of fungi from the genera Fusarium, Geotrichum, Myrothecium and Mucor (Wu et al, 2006), besides other microorganisms, such as bacteria (Aguayo et al, 2013).…”

Decomposition kinetics of gaseous ozone in peanuts

“…Of the various types of mycotoxins, aflatoxins stand out as presenting high acute and chronic toxicity in animals, including human beings; they can also cause liver damage, such as cirrhosis and hepatocellular carcinoma, in addition to teratogenic effects (ABDULKADAR et al, 2000). In this context, ozone has been proposed as either a fungicide, preventing aflatoxins from being produced, or as a healing agent that can detoxify contaminated products (MCKENZIE et al, 1998;GÜZEL-SEYDIM et al, 2004;WU et al, 2006;YOUNG et al, 2006;ZOTTI et al, 2008).…”

Saturação do ozônio em coluna contendo grãos de amendoim e efeito na qualidade

“…O ozônio pode evitar e/ou inibir o desenvolvimento dos fungos potencialmente aflatoxigênicos (ALENCAR et al, 2012) e, consequentemente, diminuir o risco de produção de aflatoxinas. Encontram-se, na literatura, diversos relatos que descrevem o efeito do ozônio sobre microrganismos, dentre os quais, os fungos dos gêneros Aspergillus, Fusarium, Geotrichum, Myrothecium, Alternaria, Penicillium, Botrytis e Mucor (RAILA et al, 2006;WU et al, 2006;ZOTTI et al, 2008), além de vírus, protozoários e bactérias (KIM et al, 1999a;KHADRE et al, 2001;AGUAYO et al, 2006;ÖZTEKIN et al, 2006). A inativação de microrganismos pelo ozônio, segundo Cullen et al (2009), é atribuída, principalmente, à ruptura do envoltório celular e posterior dispersão dos constituintes citoplasmáticos, uma vez que esse gás apresenta alto potencial oxidativo.…”