Influence of organic and mineral-based conventional fertilization practices on nutrient levels, anti-proliferative activities and quality of sweet red peppers following cold storage

Abstract

The demand for organic food products has increased over the last decades; however, the health effects of organically grown products are controversial and knowledge about how different fertilization regimes affect nutritionally and health relevant components is still limited. The aim of the present study was to determine the effect of organic and conventional mineral-based fertilizers on the quality of sweet red peppers. The parameters tested were anti-proliferative activity against cancer cells and the concentrations of antioxidants, flavonoids, phenolics, and vitamin C. The decay incidence, percentage of weight loss, and total soluble solids (TSS) content were also evaluated. The different parameters were tested in fresh peppers immediately after harvest and after cold storage. Our results show that the anti-proliferative activity of pepper extracts against colon cancer cells is similar in fresh organically and conventionally fertilized sweet red peppers. While in conventionally fertilized peppers the extent of the anti-proliferative activity was not affected by long storage, stored organic peppers lost 50% of their inhibitory activity. We also found that the levels of antioxidants, polyphenols, flavonoids, and vitamin C, as well as the general quality of the peppers were not significantly affected by the different fertilization practices nor by long storage.