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A plant’s stress response involves the production of phytochemicals, including phenolic compounds. Their synthesis can be modulated by organic (ORG) or non-organic (NORG) farming systems in which they are grown. To examine this issue, thirteen plant-based foods cultivated in ORG and NORG systems were compared in terms of antioxidant capacity, total content of phenolics, anthocyanins, flavan-3-ols and flavonols. The results showed that NORG fruits tended to have higher phenolic compounds content, whereas ORG fruits had more antioxidant capacity. NORG legume stood out for having higher values from all the parameters analyzed in comparison to its ORG equivalent. ORG nuts showed more flavan-3-ols and flavonols than their NORG counterparts, nonetheless, tended to be less antioxidant. ORG vegetables displayed higher phenolics and anthocyanins, which reflected in higher antioxidant capacity than NORG ones. These findings suggest that farming systems differentially modulate phenolic compound composition and antioxidant capacity based on the plant species studied.

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. Wine lees (WL) are by-products generated in the winemaking process. The aim of this study was to investigate the angiotensin-converting enzyme inhibitory (ACEi) activity, and the blood pressure (BP) lowering effect of WL from individual grape varieties. The relationship among their activities and phenolic profiles was also studied. Three WL, from Cabernet, Mazuela, and Garnacha grape varieties, were firstly selected based on their ACEi properties. Their phenolic profiles were fully characterized by UHPLC-ESI-Q-TOF-MS. Then, their potential antihypertensive effects were evaluated in spontaneously hypertensive rats (SHR). BP was recorded before and after their oral administrations (2, 4, 6, 8, 24, and 48 h) at a dose of 5 mL/kg bw. Cabernet WL (CWL) exhibited a potent antihypertensive activity, similar to that obtained with the drug Captopril. This BP-lowering effect was related to the high amount of anthocyanins and flavanols present in these lees. In addition, a potential hypotensive effect of CWL was discarded in normotensive Wistar– Kyoto rats. Finally, the ACEi and antihypertensive activities of CWL coming from a different harvest were confirmed. Our results suggest the potential of CWL for controlling arterial BP, opening the door to commercial use within the wine industry.

© 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism Background & aims: The peptide and protein composition of olive oil is mostly unknown and the few studies available have not focused on the study of its low molecular weight peptides. We hypothesised that olive oil could naturally contain low molecular weight peptides with antihypertensive effect. Methods: We produced virgin olive oil (unfiltered, var. Picual) and obtained a water-soluble peptide extract. We fractionated the peptide extract by FPLC and studied its angiotensin converting enzyme (ACE) inhibitory activity. We studied the antihypertensive effect of olive oil peptides on the systolic blood pressure (SBP) and diastolic blood pressure (DBP) using an animal model of hypertension (spontaneously hypertensive rats, SHR). The animals were randomly distributed into 3 study groups (n = 8 per group) and received an oral dose of olive oil peptides (0.425 mg/kg of BW), or a dose of Captopril (50 mg/kg of BW) or water. SBP and DBP were registered in the rats before administration and a at 2, 4, 6, 8, 24 and 48 h post-administration of the corresponding dose. Results: The peptide extract and FPLC purified fractions possessed angiotensin converting enzyme (ACE) inhibitory activity. Acute oral administration of olive oil water-soluble extract produced an average blood pressure reduction of 10 mmHg at 4 h (P < 0.01) and reached a maximum antihypertensive effect of 20 mmHg at 6 h, compared with baseline. Conclusion: Unfiltered virgin olive oil contains peptides and a water-soluble extract obtained from this oil possesses ACE inhibitory activity and in vivo antihypertensive effect.