Phenolic compounds (flavonoids and phenolic acid derivatives) are major active constituents of the resinous fraction of propolis, and also represent its allergenic principles. We have developed a chromatography electrospray ionisation tandem mass spectrometry (HPLC-ESI-MS/MS) method to characterise the polyphenolic fraction of propolis rapidly and quali-quantitatively. With precursor ion scanning, selective detection of caffeic esters was easily achieved, confirming the identification of prenyl caffeate, benzyl caffeate and phenylethyl caffeate by comparison with synthetic standards. The ionisation and fragmentation behaviour of the major propolis flavonoids was rationalised and applied to selected real samples. Taken together, the results of this study show that the introduction of precursor ion analysis leads to a significant improvement in the characterisation of the phenolic fraction of propolis, paving the way to the establishment of a better quality control for this important natural remedy.

Triacylglycerols (TAG) from milk-fat from different sources (cow, goat and human milks) were characterised using non-aqueous reversed phase high-performance liquid chromatographyatmospheric-pressure chemical ionisation, coupled to MS/MS (RP HPLC-APCI MS/MS). The fatty-acid content of all samples was also established by methyl transesterification and GC-MS analysis. Optimisation of the HPLC gradient, combined with APCI tandem MS, enables TAGs complex mixtures to be analysed without prior separation. More than 160 different glycerides were identified; between 50 and 70 compounds were identified in the chromatograms of each sample. This method also enabled the principal TAG regioisomers to be recognized. The study focused on the investigation of the structure of TAGs containing very-long-chain PUFA, namely all 7,10,13,16, C 22:6, ) and all 8,11,14, C 20:5, n-3 ), both in human and in n-3-enriched cow's milks. Ten TAGs containing DHA were identified in human milk and only one in milk from cows fed an n-3 enriched diet.

The popularity of small berries has rapidly increased in Western countries given their antioxidant, anti-inflammatory, and antimicrobial activities and health-promoting properties. The aim of this study was to compare the fatty acid (FA) profile, phenolic compounds, and antioxidant capacity of extracts of 11 berries cultivated in the North West of Italy. Berry samples were extracted and evaluated for FA profile and total anthocyanin (TAC), total flavonoid contents (TFC), ferric-reducing antioxidant power (FRAP), and for their radical scavenging activities against 2,2′-diphenyl-1-picrylhydrazyl (DPPH•) radical. The main polyphenols of berry extracts were characterized by HPLC-DAD-UV-ESI HRMS in positive ion mode. Results showed that the highest TAC and TFC contents were recorded in black currants, blackberries, and blueberries. Maximum and minimum DPPH• radical scavenging activities, Trolox Equivalent Antioxidant Capacity, and FRAP measurements confirmed the same trend recorded for TAC and TFC values. HPLC-HRMS analyses highlight how blueberries and blackberries have the highest concentration in polyphenols. Palmitic, stearic, oleic, linoleic, α-linolenic, and γ-linolenic acids significantly differ between berries, with oleic and α-linolenic acid representing the most abundant FAs in raspberries. Among the berries investigated, results of phytochemical characterization suggest choosing black currants and blueberries as an excellent source of natural antioxidants for food and health purposes.

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