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Olive leaves currently represent a waste from olive oil industry that can be reused as source of polyphenols and other compounds. The objective of this study was to test whether incorporation of olive leaf powder directly in olive oils can enhance and modify its chemical‐sensory quality. Thus, leaves from cultivar "Koroneiki" were washed, sanitized, dried (37–40°C for 48 h) and milled until obtaining a powder that was added to "Arbequina" and "Koroneiki" extra virgin olive oils, at 1% and 3%. The oils were stored in dark conditions at room temperature and samples were checked after 0, 3, 6 and 12 months. The quality parameters, sensory properties, and nutrition quality (total phenolics, antioxidant, oleuropein and alpha‐tocopherol) were evaluated. The olive leaves affected quality and chemical composition, mainly increasing resistance to oxidation, which was not verified in samples without leaves addition. The incorporation of leaves powder significantly increased the contents of C6‐C5 alcohols/aldehydes, intensity of the green fruity and bitter, also artichoke, herbs, tomato leaf, olive leaves and banana peels sensations. [ABSTRACT FROM AUTHOR]

Aqueous and hydro-ethanolic extracts of Bauhinia microstachya leaves (AEBM and HEBM) were investigated for their phenolic content and phytochemical profile (by spectrophotometry and HPLC), and for their antioxidant activities and free radical scavenging potential in different in vitro systems (TRAP, TEAC, TBARS, nitric oxide, superoxide and hydroxyl radical). HEBM presented a 27.4% higher content of phenolics when compared to AEBM and a distinct phytochemical profile was observed. Our work suggests that both extracts have potent antioxidant activities and that their antioxidant capacity and efficiency vary according to the radical-generating system. In general, HEBM was more effective than AEBM in avoiding ROS-generating damage and in scavenging the various radicals formed. Nevertheless, when results were normalized to total phenolic content, a different profile of antioxidant activities and free radical scavenging potential was observed, particularly against oxidative lipid damage and superoxide radical. B. microstachya extracts may be considered an interesting source of natural antioxidants as well as other phenolic-rich plants.