Beer is a fermented beverage in which antioxidants can contribute to the oxidative stability and nutraceutical properties of the product. Aronia berries are antioxidant-rich fruits of distinct sour and astringent taste, limiting their culinary uses. Previously, fermentation has proven to be effective in the removal of astringent tastes from various fruit juices. In this study, a single malt pale ale was produced and infused with Aronia berries under various process conditions by adding the antioxidant-rich fruits at different stages of the beer brewing process. The polyphenol content, antioxidant potential and color were determined. There was a positive correlation between the Aronia amount added and antioxidant capacity. Higher concentrations of added Aronia also increased the polyphenol content and EBC color rating, while no change in the resulting pH was observed. An increase in the Aronia amount increased the attenuation, showing a positive effect on sugar utilization during fermentation. The addition of Aronia after the boil yielded the highest coloration and antioxidative capacity, while addition before the boil yielded a similar antioxidative capacity with a lower EBC rating. Taken together, the infusion of pale ale with Aronia berries can increase the EBC rating, polyphenol content and antioxidative capacity of the beer.

Heavy metals have adverse effects on microalgae metabolism and growth. Photosynthesis and lipid profile are quite sensitive to heavy metal toxicity. The impact of hexavalent chromium—Cr(VI) on photosynthesis and lipid accumulation in Mucidosphaerium pulchellum and Micractinium pusillum exposed to different concentrations (0–500 μg L⁻¹) was investigated for 11 days. A significant (p < 0.05) increase in lipid content was observed with increasing Cr(VI) concentration. However, growth was suppressed at higher concentrations exceeding 100 μg L⁻¹. Addition of Cr(VI) in the cell culture medium showed a negative effect on quantum yield (F_v/F_m), and a photosynthetic inhibition of >65% was noted in both species at 500 μg L⁻¹. However, the lipid gravimetric analysis presented inner cell lipid content up to 36% and 30% of dry weight biomass for M. pulchellum and M. pusillum, respectively. The fatty acids profiles of both microalgae species showed higher levels of hexadecenoic acid as well as ω3, ω6, and ω7 fatty acids. The effect of Cr(VI) on photosynthesis and lipid accumulation in both microalgae species was concentration and exposure time dependent. This shows that an appropriate concentration of Cr(VI) in culture medium could be beneficial for higher lipid accumulation in freshwater eukaryotic microalgae species.

Heavy metals have adverse effects on microalgae growth and metabolism. Photosynthesis and lipid profile are quite sensitive to heavy metal toxicity. The impact of chromium (Cr) on growth and photosynthetic activity of Dictyosphaerium pulchellum and Micractinium pusillum exposed to different concentrations (0 – 500 μg L-1) was investigated for 11 days. The influence of Cr on cell density and cell number followed similar trends, indicating a possible correlation among these growth responses. A significant (p < 0.05) increase in lipid content was observed with the increasing concentration of Cr however, growth was suppressed at higher concentrations exceeding 100 μg L-1. Addition of Cr in the cell culture medium showed a negative effect on quantum yield (Fv/Fm) and a photosynthetic inhibition of > 65% was noted in both species at 500 μg L-1. However, the lipid gravimetric analysis presented inner cell lipid content up to 36% and 30% of dry weight biomass for D. pulchellum and M. pusillum, respectively. The effects of chromium on growth and lipid accumulation in both microalgae species was concentration and exposure time dependent. This shows that an appropriate concentration of chromium in culture medium could be beneficial for higher lipid accumulation in freshwater eukaryotic microalgae species.