Phomopsin-A and Quinolizidine Alkaloids Concentrations in Lupinus albus Seeds: Effect of Aqueous and Gaseous Ozone Application

TL;DR

This study explores using ozone to reduce harmful substances in lupin seeds, a potential meat substitute, to improve safety.

Contribution

The study introduces ozone treatment as a sustainable method to detoxify lupin seeds from quinolizidine alkaloids and phomopsin-A mycotoxins.

Findings

Aqueous ozone reduced phomopsin-A by about 20% and some quinolizidine alkaloids in lupin seeds.

Aqueous ozone also significantly reduced the count of Diaporthe toxica after 4 hours of treatment.

Gaseous ozone treatments showed no significant effect on reducing phomopsin-A or quinolizidine alkaloids.

Abstract

Recent studies on novel protein sources unveiled lupins as a promising substitute for meat consumption. However, lupin cultivation and processing include significant safety concerns, such as quinolizidine alkaloids (QAs) and the possible growth of toxigenic fungi as Diaporthe toxica, which produces the mycotoxin phomopsin-A (PHO-A). Therefore, this study aims to assess the influence of gaseous and aqueous ozone on lupin beans as environmentally sustainable methods for detoxifying QAs and PHO-A mycotoxins, thereby addressing both these safety challenges. Three distinct aqueous and gaseous ozone treatments (4, 6, and 8 h, at 7.00 ppm O3 concentration) were applied on lupin seeds inoculated with D. toxica DSM 1894. A good effectiveness of aqueous O3 in the reduction in PHO-A (about 20%) was demonstrated, independently of the treatment duration, along with the reduction in some QAs typically encountered in lupin. Additionally, a significant reduction in D. toxica count was observed after 4 h treatment with aqueous O3. In contrast, results for gaseous O3 treatments did not show any significant effectiveness on either PHO-A or QAs. Conversely, none of the treatments applied significantly affected lupin color. In conclusion, aqueous ozone treatment demonstrated significant potential for the reduction in PHO-A and QAs, and the insights acquired from this work may aid in mitigating the dangers associated with lupin intake. Nevertheless, additional research is required to cover current knowledge gaps. Specifically, toxicological assays on PHO-A degradation by-products or O3 combination with other hurdles is required to enhance treatments and preserve lupins’ nutrients.

Figures