Eighty-eight extracts of different polarity obtained from 18 Lamiaceae medicinal and aromatic plants were screened for their antioxidant and antifungal properties. A TLC analysis combined with two bioassays were used to detect these activities. In most cases the highest radical scavenger capacity was detected in methanolic and aqueous extracts and polyphenols may be responsible. The most interesting antioxidant activity was observed in polar extracts obtained from Lycopus europaeus, Melissa officinalis, Origanum vulgare subsp. virens and Lavandula latifolia. On the contrary, the best results for the antifungal test against Rhizopus stolonifer were produced by non-polar herbal extracts. Phlomis lychnitis, Salvia pratensis and Calamintha sylvatica caused the highest inhibition on Rhizopus growth.

Available online A B S T R A C TTotal phenolic, flavonoid and anthocyanin contents of dichloromethane, ethyl acetate, ethanol, and aqueous extracts of branches, leaves and fruits from Prunus spinosa were quantified by spectrophotometrical methods and the results showed solvent and botanical organ dependence. In order to detect antioxidant activity, a method based on the reduction of DPPH was carried out. Activity of ethanol, ethyl acetate and aqueous extracts of branches demonstrated a higher scavenging capacity compared to other analysed extracts. Phytochemical analysis allowed detecting flavonoids, coumarins, phenolic acids and flavan-3-ols. Ethanolic extract of branches was subjected to an in vitro digestion. Buccal and gastric digestion had no substantial effect on any of the phenolic compounds. However, these compounds were significantly altered during intestinal digestion. The results showed that a significant proportion of these compounds would be transformed into other unknown and/or undetected structural forms. Furthermore, three phenolic acids, two coumarins, fourteen flavan-3-ols, and six flavonols were identified using HPLC-DAD-ESI-MS.

Aqueous and hydroalcoholic extracts from Verbena officinalis L were obtained and characterized. The analysis by HPLC-DAD and LC-MS allowed the detection and identification of three iridoids, fifteen flavonoids and four phenolic acid derivatives. Four flavonoids, scutellarein 7-diglucuronide (9), scutellarein 7-glucuronide (13), pedalitin 6-galactoside (15) and scutellarein 7-glucoside (19) are reported for the first time from this plant. In addition, three new flavonoids have been isolated: scutellarein 7-O-(2-O-feruloyl)-diglucuronide (5), pedalitin 6-O-diglucuronide (6) and pedalitin 6-O-(2-O-feruloyl)-diglucuronide (13). To our knowledge, these flavonoids have not been reported as natural products. Both extracts showed significant antioxidant activity using three in vitro model systems and the results have been correlated with total phenolic and total flavonoid contents. The results have allowed establishing an important relation structure-activity and significant correlations have also been found between the mineral content and the flavonoids present in both extracts.

No abstract

The effect of storage temperature (65°C, 48 hours) on the oxidative stability of a food-grade water-in-oil-in-water (W/O/W) emulsion was studied by comparison with an oil-in-water (O/W) emulsion. The emulsions were prepared with linseed oil or olive oil, and in each case, two antioxidants were evaluated, an aqueous Melissa lyophilized extract and BHA. Emulsions were characterized using brightfield light microscopy and the oxidation was monitored by measuring the lipid hydroperoxides, thiobarbituric acid reactive substances (TBARS),

Background: An ethnobotanical and medical study was carried out in the Navarre Pyrenees, an area known both for its high biological diversity and its cultural significance.

The bioaccessibility and antioxidant activity of rutin, caffeic acid and rosmarinic acid were evaluated using three in vitro gastrointestinal digestion models: filtration, centrifugation and dialysis. At intestinal level, a significant degradation of all compounds was observed when results were expressed on concentration basis (mg/mg lyophilized sample), mainly due to the dilution effect that occurs during digestion. However, when results were expressed as absolute amounts (total mg in the digested fraction), this degradation was much lower, or even absent in the case of rutin. Moreover, bioaccessibility (in terms of total mg) was higher in filtration and centrifugation than in the dialysis method. A significant reduction of antioxidant activity was observed after intestinal digestion of the three standards, regardless of the method used. In conclusion, the methodology and units used to report results are two critical parameters to take into account in bioaccessibility studies.

Melissa officinalis L. (Lamiaceae) is consumed as a traditional herbal tea in the Mediterranean region. The cytotoxic effect of the 50% ethanolic and aqueous extract, determined by the MTT and NR assays, was evaluated in vitro on Human Colon Cancer Cell Line (HCT-116), using Triton 10% as positive control. The 50% ethanolic extract showed significant differences after 72 h of treatment, reducing cell proliferation to values close to 40%, even the lowest dose tested (5 μg/ml). In the MTT assay, the same extract caused the lowest cell viability with 13% at a concentration of 1,000 μg/ml after 72 h of treatment, being a value lower than Triton 10%. The antioxidant activity was also confirmed evaluating the capacity of the extracts to scavenge ABTS and DPPH radicals, and IC(50) values were highly correlated with the total phenolic and flavonoid content. Bioassay guided fractionation led to the isolation of an anti-proliferative compound, rosmarinic acid. Its structural elucidation was performed by HPLC/DAD/ESI/MS analysis. High dose of rosmarinic acid (1,000 μg/ml) was clearly cytotoxic against HCT-116 cells, with a significant decrease in cell number since the earliest time point (24 h).