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- Volatile chemical characterization and biological activity assessment of Portuguese honey types : importance of botanical originPublication . Machado, Alexandra; Figueiredo, Ana Cristina; Miguel, Maria Graça; Vilas Boas, MiguelHoney is recognized as a high-quality food product with increased consumption in recent years, and with consumer´s showing a trend for honeys with distinctive organoleptic characteristics. This encourages honey falsification, but also promotes analytical tools development to ensure compliance with quality criteria. Honey biological properties have also gained interest in a world of consumers with increased health awareness, seeking wellbeing through food. In this study, fifty-one producers’ labelled monofloral honeys, from mainland Portugal and Azores islands, were evaluated, namely, carob tree, chestnut, eucalyptus, bell heather, incense, lavender, orange, rape, raspberry, rosemary, sunflower, and strawberry tree honeys. This work aimed at contributing to the knowledge of monofloral Portuguese honeys considering a) melissopalynological analysis, b) microbiological quality control, c) physicochemical characterization, d) volatile profile evaluation, e) botanical source differentiation, f) in vitro biological activities assessment and g) phenolic content of selected honey types. Regarding botanical source 53% of the honeys were confirmed as monofloral and the remaining as multifloral. The honeys showed microbiological quality for human consumption, within the acceptance criteria for aerobic mesophilic bacteria, and for yeasts and moulds. Physicochemical characterization defined that electrical conductivity, colour, free and total acidity, and diastase activity could contribute to monofloral honeys differentiation. n-Nonadecane, n-heneicosane, n-tricosane, n-pentacosane, palmitic, linoleic and oleic acids were the main volatiles found in the honey samples, while in lower amounts, cis- and trans-linalool oxide (furanoid), hotrienol, α-isophorone, benzene acetaldehyde and 3,4,5-trimethylphenol were also identified. Fully grown classification tree analysis identified twelve volatile compounds able to fully discriminate between eleven honey types, according to the botanical source. Antimicrobial activity against Staphylococcus aureus and reactive oxygen species (ROS) formation reduction were more pronounced with chestnut, eucalyptus, bell heather, and strawberry tree honeys, while wound healing activity with orange and incense honeys. Bell heather and strawberry tree honeys showed the highest amount in total phenolics. To date this is the first study integrating several characteristics of Portuguese monofloral honeys and providing putative parameters to differentiate them. This work also highlights the great therapeutic potential of some honeys for the development of pharmaceutical formulations.
- Influence of orchards fertilization management and post-harvest storage time on Malus domestica cv. ‘Gala’ fruit volatiles and quality parametersPublication . Figueiredo, Ana Cristina; da Silva, Anabela Bernardes; Tavares, Cláudia; Pastaneira, Mafalda; Melo, Juliana; Ferro Rodrigues, Carolina; Machado, Alexandra; Antunes, Marília; Cruz, Cristina; da Silva, Jorge Marques; Matos, Ana Rita; Pedro, Luís; Barroso, José; Almeida, Patrícia; Maurício, Anabela; Rosa, Cristina; Faria, João; de Sousa, Miguel L.; Santos, Ricardo; Raimundo, Délio; Oliveira, Cristina“Maçã de Alcobaça” is a type of apple from the West coast of Portugal with Protected Geographical Indication (PGI). This study evaluated the influence of the orchard’s fertilization and post-harvest storage time on the quality of “Maçã de Alcobaça”, ‘Gala’ cultivar. Five orchards were studied for four years, using three fertilization treatments [Standard, twice Standard (2xStandard) and twice Standard including organic matter (2xStandard_OM)]. The fruits’ volatile profile, emanation index, and quality parameters were determined in apples after harvest time (T0), three- (T3) and five months (T5) after storage. At T0, the intact apples volatiles were dominated by trans,trans-α-farnesene (48–79 %). trans,trans-α-Farnesene emanation index was larger in T0 apples independently of the orchard and fertilization treatment, and showed an accentuated decrease from T0 to T5. Fruits quality at T0 and T5, showed significant differences per orchard, but their average weight, TSS, and firmness, were not significantly altered with fertilization treatment. Storage did not significantly affect the fruits weight, but TSS and firmness always decreased regardless of the orchard or fertilization treatment. Among other things, the observed variations among orchards after fertilization treatments may relate to the cultural practices of each orchard as well as the fact that their ages and rootstocks varied.
- Azorean Cryptomeria japonica immature female cones essential oil: Effect of hydrodistillation fractionation on the chemical composition and in vitro antifungal activity against Thielaviopsis paradoxaPublication . Arruda, Filipe; Lima, Ana; Janeiro, Alexandre; Rodrigues, Tânia; Baptista, José; Rosa, José S.; Machado, Alexandra; Figueiredo, Ana Cristina; Lima, ElisabeteCryptomeria japonica's wood production in Azores generates large amounts of underutilized biomass residues, such as immature female cones (Az–CJIFC), that can be used to produce essential oils (EOs). Hydrodistillation (HD) can be used both to obtain and to fractionate EOs. In this study, EOs from Az–CJIFC, grinded (GR) and non-grinded (NGr) fresh samples, were obtained via HD over 4 h, yielding 1.0 % and 0.5 %, w/w, respectively. Thus, GR Az–CJIFC was chosen to obtain six EO fractions (Frs. 1–6), collected at sequential HD timeframes (HDTs: 0–2, 2–10, 10–30, 30–60, 60–120, and 120–240 min). The obtained EO samples (crude EOs and fractions) were evaluated for their chemical composition (GC–FID/GC–MS analyses) and antifungal activity (micro-atmosphere method) against phytopathogenic fungi (Penicillium italicum, P. digitatum and Thielaviopsis paradoxa). Results indicated that all samples were active only towards T. paradoxa, however, with a differential efficacy, due to their specific composition. Fraction 4 vapor treatment displayed the strongest activity, but lower than that of (–)-terpinen-4-ol, a key oxygen-containing monoterpene (OCM) of Az–CJIFC EO, peaking its concentration in Fr3 (14.5 %) and Fr4 (13.8 %). This latter fraction was the richest in the OCM α-terpineol (a minor Az–CJIFC EOs' component). On the other hand, Frs.1–3 and EOs were dominated by monoterpene hydrocarbons (65.0–96.5 %), mainly α-pinene (19.0–28.4 %) and sabinene (19.9–50.5 %), while Frs.5 and 6 were the richest in oxygen-containing sesquiterpenes (47.1–70.8 %; chiefly elemol plus α-, β- and γ-eudesmol) and diterpene hydrocarbons (5.2–6.4 %; mostly phyllocladene). In conclusion, new high value-added products can now be targeted in Az–CJIFC EO by adjusting the HDT, with potential importance in pineapple fruit black rot disease management caused by T. paradoxa on Ananas comosus in the Azores, and also contributing for the local C. japonica’s EO industry development and sustainable circular bio-economy.