The health benefits of extra virgin olive oil (EVOO), including improved cardiovascular health and metabolic function, are linked to its phenolic content. This study evaluated how storage duration and packaging affect the phenolic composition and sensory quality of Corbella EVOO. Oils were analyzed at production and after 6 and 12 months of storage in two types of packaging: bag-in-box; stainless steel containers with a nitrogen headspace. UPLC-MS/MS profiling quantified 23 phenolic compounds, predominantly secoiridoids such as oleuropein and ligstroside aglycones. Oleuropein aglycone increased over time, whereas ligstroside aglycone peaked mid-storage before declining, likely converting to oleocanthal. Lignans and flavonoids degraded during storage, although luteolin increased, potentially due to glucoside hydrolysis. Bag-in-box packaging better preserved phenolic content than stainless steel. A sensory analysis corroborated the chemical findings, with oils stored in stainless steel showing greater reductions in pungency and astringency. A Pearson correlation linked bitterness with oleuropein aglycone (r = 0.44) and oleacein (r = 0.66), pungency with oleocanthal (r = 0.81), and astringency with oleacein (r = 0.86) and oleocanthal (r = 0.71). These findings highlight the importance of packaging in preserving the phenolic composition responsible for the sensory qualities of EVOO over time.

Background: Phenylketonuria (PKU) is a rare metabolic disorder caused by a deficiency in the enzyme phenylalanine hydroxylase, leading to the accumulation of phenylalanine (Phe). Raised Phe levels can result in neurocognitive deficits, intellectual disabilities, and behavioral or psychiatric disorders. Aim of review: To conduct a systematic review of human studies on metabolites identified through metabolomics in individuals with PKU, compared to healthy controls, and to provide insights into their biological significance. Key scientific concepts of review: A total of 26 human studies analyzing metabolites in urine and blood met the inclusion criteria. In total, 544 metabolites that differed between patients with PKU and healthy controls were identified through different metabolomic techniques (LC-MS, GC-MS, NMR). Differences were primarily observed in blood samples, which accounted for 95% of the total metabolites, with only 5% detected in urine samples, reflecting the limited use of this body fluid in only five studies. We found 60% of blood metabolites upregulated in patients with PKU, including Phe, Phe-related metabolites, lipids, and other amino acids, while tryptophan and kynurenine, among others, were downregulated (40%). Additionally, 35 metabolites (6% of the total) exhibited inconsistent directions of change (both up- and downregulated), including amino acids, carnitine derivatives, and lipids. These findings may be attributed to clinical factors (dietary adherence, supplementation, and treatment) and methodological differences in blood-derived matrices. Consequently, the high heterogeneity across studies, biological matrices and analytical platforms represents limitations for establishing a unique metabolomic signature. Overall, these results emphasize the metabolic complexity of PKU and highlight the potential of metabolomics to advance disease monitoring and management.

Walnuts (Juglans regia L.) are attracting increasing interest from consumers, industries, and the healthcare community due to their high content of bioactive compounds, including (poly)phenols, carotenoids, tocopherols, and omega-3 fatty acids. Despite the continued growth in global walnut production, the effective valorisation of walnut processing by-products remains a challenge. While most research has focused on the edible kernel, emerging evidence suggests that underutilised walnut fractions may also represent valuable sources of compounds with antioxidant and anti-inflammatory properties. This study aimed to characterise the bioactive compound profiles of green walnuts, defective walnuts, and walnut shells in comparison with commercial whole walnuts and kernels. Samples collected from an orchard located in Huesca (Spain) were homogenized and analysed in triplicate. Proximate composition was determined using official methods, the fatty acid profile was determined by GC-FID, the phenolic profile by UHPLC-ESI-MS/MS, and carotenoids and tocopherols by UPLC-DAD. Green walnuts contained exceptionally high concentrations of carotenoids, especially β-carotene (629.7 ± 39.4 mg kg⁻¹). Walnut shells were the richest source of phenolic compounds, notably ellagic acid (713.3 ± 7.6 mg kg⁻¹) and catechin (71.9 ± 1.2 mg kg⁻¹). Tocopherols were mainly concentrated in the kernel, dominated by γ-tocopherol (226.9 ± 8.1 mg kg⁻¹), while defective walnuts showed a compositional profile similar to commercial walnuts. This comparative analysis highlights the significant potential of walnut processing by-products as sources of nutritionally relevant bioactive compounds. These findings support their valorisation as functional ingredients for agro-food and cosmetic applications within a circular economy framework.