MS tools for a systematic approach in survey for carotenoids and their common metabolites.

Metabolism of the carotenoids in humans is often reserved to bioconversion of provitamin A carotenoids in retinoids and oxidative/degradative products arising from enzymatic eccentric cleavage, yielding apo-carotenoids. Nevertheless, additional metabolic routes should be available, and some of the structures of those metabolites have only been anticipated. The identification of carotenoids and their metabolites is commonly performed by HPLC coupled to MS. The acquisition of MS data in different instrumental modes and hardware configurations allows the detailed structural description of the target compound. Indeed, the MS data of carotenoids and their metabolites available in literature could be collected in a database to automatically perform a screening of the theoretical MS data included in the database with the MS experimental values. This review describes the required fundamentals for a systematic pursuit of carotenoids and their metabolites. Highlights on the use of appropriate hyphenated HPLC-MS systems and the requirements for the identification are discussed, while the application of software tools to apply filtering rules and the implementation of post-processing workflow, which uses two orthogonal criteria for the identification from the mass spectra data, are described.

Trials of bioremediation on a beach affected by the heavy oil spill of the Prestige.

The objective of this study was to assess the efficiency of several bioremediation products in accelerating the in situ biodegradation of the heavy fuel oil spill of the Prestige. Trials of bioremediation were conducted in sand, rocks and granite tiles on the beach of Sorrizo (A Coruña, NW Spain) that was polluted by the spill. Neither the added microorganisms nor the nutrients significantly enhanced the degradation rate of the fuel oil in rocks, granite tiles or sand. PAH degradation up to 80% was determined in sand and tiles. In tiles the oxygen content of the residual oil increased from 1.6% up to 8% in 90 days, which could be explained by the accumulation of products coming from the partial oxidation of the hydrocarbons. Eighteen months after the spill, the rocks of the beach were still coated by a black layer of weathered fuel oil. For this reason an oleophilic product, sunflower biodiesel was tested on a rock. The application of biodiesel accelerated the gradually clean-up of the polluted surface and could also accelerate the degradation of the residual oil.

Astaxanthin is the major carotenoid in tissues of white storks (Ciconia ciconia) feeding on introduced crayfish (Procambarus clarkii).

We studied the carotenoid pigments in plasma, skin and body fat of white storks (Ciconia ciconia) from a colony in Spain feeding mainly on the recently introduced red swamp crayfish (Procambarus clarkii). In control colonies, where crayfish was absent, plasma was collected for comparison. Our objective was to determine whether the astaxanthin contained in the crayfish reached the blood, accumulated in fat, and finally was deposited in the red-colored bill and legs. If that was true, the visual cues provided by those tegumentary areas would be altered, with potential behavioral consequences. Plasma carotenoids were directly extracted with acetone, whereas skin and fat samples needed harsher conditions, i.e. grinding, sonication and extraction with diethyl ether. The extracts were analyzed by thin-layer chromatography (TLC) and UV/Vis spectroscopy. In crayfish-eating storks, astaxanthin was confirmed to be the dominant pigment in all analyzed tissues. This red pigment was absorbed unchanged in the gut, and was responsible for the red color of plasma and the abnormal orange pigmentation of the feather-covered skin. It was also present in large quantities in the exposed bill and tarsi, which are typically red-colored in the stork. Control storks with no crayfish in the diet only presented lutein in their plasma.

Carotenoid content of the varieties Jaranda and Jariza (Capsicumannuum L.) and response during the industrial slow drying and grinding steps in paprika processing.

Fruits of the pepper varieties Jaranda and Jariza (Capsicum annuum L. ) ripen as a group, enabling a single harvesting, showed a uniform carotenoid content that is high enough (7.9 g/kg) for the production of paprika. The drying system at mild temperature showed that fruits with moisture content of 85-88% generated a dry product with carotenoid content equal to or higher than the initial one. Those high moisture levels allowed the fruits to have a longer period of metabolic activity, increasing the yellow fraction, the red fraction, or both as a function of what biosynthetic process was predominant. This fact indicates under-ripeness of the fruits in the drying step. The results obtained allow us to establish that both varieties, Jaranda and Jariza, fit the dehydration process employed, yielding a dry fruit with carotenoid concentration similar to that the initial one. During the grinding step of the dry fruit, the heat generated by the hammers of the mill caused degradation of the yellow fraction, while the red fraction is maintained. The ripeness state of the harvested fruits and the appropriateness or severity of the processing steps are indicated by the ratio of red to yellow (R/Y) and/or red to total (R/T) pigments, since fluctuations in both fractions and in total pigments are reflected in and monitored by these parameters.

Diet explains interpopulation variation of plasma carotenoids and skin pigmentation in nestling white storks.

Carotenoids have a dietary origin in birds, but mechanisms by which they are absorbed in the gut, transported in the blood, metabolized at various sites, and deposited in the integument remain poorly understood. Variation in both plasma carotenoid levels and external color may reflect different access to dietary carotenoids or individual physiological differences in the uptake and deposition of carotenoids. We compared total plasma carotenoid concentration in nestling white storks (Ciconia ciconia) from 11 Spanish colonies in two consecutive years. The main food item in one of the colonies was the red swamp crayfish (Procambarus clarkii), a recently introduced species. Storks in the remaining colonies ate a variety of foods but no crayfish. Total plasma carotenoid levels in the colony where crayfish were consumed were about five times higher than in any other colony. These differences were maintained after controlling for the significant interyear variability, as well as for sex, age, and body mass of birds. Skin pigmentation also differed, being intensely orange in storks that consumed crayfish but white (unpigmented) in the remaining individuals. With thin-layer chromatography (TLC) and electronic absorption spectroscopy, astaxanthin was confirmed as the major carotenoid in crayfish as well as in the plasma, skin, and body fat of crayfish-eating storks, whereas lutein was the main carotenoid in plasma samples from the other colonies. These results indicate that a newly available carotenoid in the environment, astaxanthin, can be absorbed in large quantities from the gut and be transported in the blood before deposition in different tissues.

Detection of bixin, lycopene, canthaxanthin, and beta-apo-8'-carotenal in products derived from red pepper.

An analytical method using either thin layer or liquid chromatography is proposed for the detection of 4 pigments (bixin, lycopene, canthaxanthin and beta-apo-8'-carotenal) that can be used fraudulently to intensify the natural color of products derived from red pepper (oleoresins, paprika, paprika paste, etc.). Similarly, the addition of other colorant natural products containing some of these pigments as major pigments (such as tomato for lycopene and Bixa orellana seeds for bixin) can be detected. The method proposed can also be used to control the aforementioned pigments in their natural sources as well as in food products.