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a b s t r a c tAlginates are naturally occurring components of organic matter in natural soil whose effects on nanoparticles (NPs) toxicity to plants is not well understood. In the present study, corn plants were grown for one month in soil spiked with 400 mg/kg CeO 2 NPs with various alginate concentrations. After one month of growth in the NPs impacted soil, plants were harvested and analyzed for Ce and mineral element concentrations. Chlorophyll concentration and heat shock protein 70, used as biomarkers for oxidative stress, were also evaluated. Results showed that, compared to CeO 2 NPs treatment, alginate at 10, 50, and 100 mg/kg increased Ce concentration in roots by approximately 46%, 38%, and 29% and by 115%, 45%, and 56% in shoots, respectively. CeO 2 NPs without alginate increased Mn accumulation in roots by 34% compared to control. CeO 2 NPs with low and medium alginate increased Mn by ca. 92% respect to NPs without alginate and by ca. 155% respect to control. CeO 2 NPs without/with alginate significantly increased accumulation of Fe and Al in roots. In addition, alginate at 50 mg/kg increased Zn accumulation in roots by 52% compared to control. In shoots, K increased at all NP treatments but the accumulation of other elements was not affected. Alginate enlarged the impact of CeO 2 NPs to corn plants by reducing chlorophyll a content and triggering overexpression of heat shock protein 70.

The effect of processing on potential changes of antioxidant activity (DPPH and ABTS), total phenolic content (TPC) and total flavonoids (FLAV) of feijoa pulp during storage was investigated. In addition, possible modifications in the phenolic composition of the pulp. The pulp was subjected to refrigeration (control, 5 °C), pasteurization (85 °C/5 min) and irradiation (2.0 kGy). TPC, FLAV, DPPH and ABTS were measured during 28 days, whereas the identification and quantification of phenolic compounds were conducted after processing. The results were submitted to principal component analysis (SAS 9.4). Pasteurization preserved TPC, DPPH and ABTS for 21 days, while in the irradiated samples and control, the values were decreased and FLAV were maintained at high levels. The profile of phenolic compounds was different for each sample with six compounds being identified.