Searching for new sources of innovative products for the food industry within halophyte aromatic plants: In vitro antioxidant activity and phenolic and mineral contents of infusions and decoctions of Crithmum maritimum L.

Aromatic halophyte plants are an outstanding source of bioactive compounds and natural products with potential use in the food industry. This work reports the in vitro antioxidant activity, toxicity, poly phenolic profile and mineral contents of infusions and decoctions from stems, leaves and flowers of Crithmum maritimum L, an aromatic and edible maritime halophyte (sea fennel). Aspalathus linearis (Burm.f.) Dahlg. (rooibos) herbal tea was used as a reference. Sea fennel's tisanes, particularly from leaves, were rich in phenolic compounds and five of them (p-hydroxybenzoic and ferulic acids, epicatechin, pyrocatechol and 4-hydroxybenzaldehyde) were here described in C maritimum for the first time. Chlorogenic acid was the dominant phenolic determined. Na was the most abundant mineral in all tisanes followed by Ca and Mg in leaves' tisanes and K in flowers. Sea fennel's samples had a similar antioxidant activity than those from A. linearis, and had no significant toxicity towards four different mammalian cell lines. Altogether, our results suggest that sea fennel can be a source of products and/or molecules for the food industry with antioxidant properties and minerals in the form, for example, of innovative health-promoting herbal beverages.FCT Investigator Programme [IF/00049/2012

Biological activities and chemical composition of methanolic extracts of selected Autochthonous microalgae strains from the Red Sea

Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 mu g/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and -carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value.National Science, Technology and Innovation Program of King Abdulaziz Medical City for Science and Technology, Riyadh, Saudi Arabia [NPST, 11-ENE 1719-02]; Foundation for Science and Technology (FCT), Portugal [SFRH/BD/78062/2011]; FCT [IF/00049/2012, SFRH/BPD/86071/2012, Pest-OE/QUI/UI0612/2013]info:eu-repo/semantics/publishedVersio

Exploring Caralluma europaea (Guss.) NEBr. as a potential source of bioactive molecules: In vitro antioxidant and antidiabetic properties, and phenolic profile of crude extracts and fractions

Caralluma europaea (Guss.) N.E.Br is a succulent medicinal species used in the Moroccan traditional medicine for its anticancer and antidiabetic properties. In this work, this species was explored for the in vitro antidiabetic and antioxidant properties of crude methanol and dichloromethane extracts, and obtained fractions, from its aerial organs. In vitro antidiabetic properties were evaluated towards baker's yeast and rat's intestinal alpha-glucosidase, and alpha-amylase. Four in vitro methods were used to appraise the antioxidant potential, namely radical scavenging activity (RSA) on 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and iron and copper chelating assays. Finally, the profile of the main phenolic compounds present in the samples was assessed by high-performance liquid chromatography equipped with diodearray detection (HPLC-DAD). The highest inhibition of baker's yeast alpha-glucosidase was obtained with the methanol extract (87%), and its fractions, with a maximum inhibition of 83% at the concentration of 10 mg/ml. The most significant inhibition of mammalian alpha-glucosidase was obtained with the dichloromethane crude extract (85%), and corresponding fractions at 10 mg/ml. Moderate activity was achieved with the two extracts against a-amylase (52-53%) at 10 mg/ml, but no relevant activity was detected for most fractions. Crude extracts had a significant RSA against DPPH and ABTS, with range values of 83-98% (methanol extracts) and 53-80% (dichloromethane extracts). Fractions from the methanol extract were more active against tested radicals. Crude extracts had chelating activity on both metals, and the highest copper chelation was achieved with the methanol extract, while the dichloromethane extract and the majority of fractions from both extracts presented the highest iron chelation at 10 mg/ml. A total of 21 phenolic compounds were identified and quantified by HPLC-DAD in the samples, and the main compounds detected were catechine hydrate and salicylic and caffeic acids. Our results suggest that C. europaea extracts contain compounds with in vitro antioxidant and antidiabetic properties with potential applications in the pharmaceutical and food industries.Foundation for Science and Technology (FCT)Portuguese Foundation for Science and TechnologyPortuguese National Budget [CCMAR/Multi/04326]FCT Scientific Employment Stimulus [CEECIND/00425/2017]FCTPortuguese Foundation for Science and Technology [SFRH/BD/116604/2016]FCT Investigator Programme [IF/00049/2012