α-Glucosidase inhibitory phenolics from Echeveria subrigida (B. L. Rob & Seaton) leaves.

Echeveria subrigida is native to Mexico and its methanol extract (ME) shows relevant biological activities for human health, including the α-glucosidase inhibitory (αGI) activity that suggests its antidiabetic potential. Fractionation of the ME based on the αGI activity (IC50 in µg/mL) showed that quercetin-3-O-ß-glucoside (131.1), isorhamnetin-3-O-ß-glucoside (166.4), and dimers to heptamers proanthocyanidins (9.6) were among the main responsible of αGI activity in the ME. The purified compounds showed better activity than acarbose (IC50 = 4426 µg/mL).

Antifungal activity of fruit pulp extract from Psidium sartorianum.

The methanol extract of the fruit pulp of Psidium sartorianum was evaluated against seven Candida spp. and nine other fungal strains that are human pathogens. The extract showed a significant activity against seven Trichophyton species. Candida species were insensitive.

Antifungal activity of fruit pulp extract from Bromelia pinguin.

The methanol extract of the fruit pulp of Bromelia pinguin was evaluated for its antifungal activity. The extract showed a significant activity against some Trichophyton strains, although Candida strains were generally insensitive.

Natural pigments: carotenoids, anthocyanins, and betalains--characteristics, biosynthesis, processing, and stability.

Pigments are present in all living matter and provide attractive colors and play basic roles in the development of organisms. Human beings, like most animals, come in contact with their surroundings through color, and things can or cannot be acceptable based on their color characteristics. This review presents the basic information about pigments focusing attention on the natural ones; it emphasizes the principal plant pigments: carotenoids, anthocyanins, and betalains. Special considerations are given to their salient characteristics; to their biosynthesis, taking into account the biochemical and molecular biology information generated in their elucidation; and to the processing and stability properties of these compounds as food colorants.

Effects of Sunlight Illumination of Marigold Flower Meals on Egg Yolk Pigmentation.

The effect of sunlight illumination of marigold flower meal on the pigmentation of feed for laying hens and of their resulting egg yolks was evaluated by high-performance liquid chromatography and by subjective and light reflectance colorimetry techniques. Illumination did not have an effect on the identity of carotenoids in the flower meal. Interestingly, illuminated marigold flower meals yielded an oleoresin with a higher all-trans-zeaxanthin level, with respect to meals kept in darkness. A higher level of all-trans-zeaxanthin was also present in feed pigmented with that oleoresin. Additionally, this pigmented feed showed the best color values and resulted in egg yolks with good color; remarkably, these egg yolks had a low pigment content with respect to control treatments. Thus, sunlight illumination of marigold flower meal showed a positive effect on egg yolk color; the main factors contributing to this effect were not the identity or quantity of carotenoids in laying hen feed or egg yolks, but rather other as yet unidentified marigold component(s) which was (were) somehow influenced by sunlight illumination.

Enzymatic treatment to enhance carotenoid content in dehydrated marigold flower meal.

The effect of enzymatic treatments using a commercial enzyme (Econase-cep at pH 5.0 and 0.1% w/w concentration) at different levels of dehydrated marigold meal (5, 10, 15 and 20% dry weight), to enhance carotenoid extraction, was evaluated. The AOAC method consisting of a simultaneous extraction and saponification by using hexane-ethanol-acetone-toluene (10:6:7:7 v/v) and metanolic KOH (40% w/v) was used to evaluate the carotenoid content. The measurement of carotenoids was also carried out in samples in which the water soluble compounds were previously eliminated (AOAC-H2O). Total carotenoids ranged from 11.4 to 17.4 g/kg and 18 to 24.7 g/kg of control and treated marigold meal, respectively. Highest amount of carotenoids were noted when 5% level of treated meal was used.