The daily ingestion of chlorophylls has been estimated at 50 g, but the knowledge about their bioaccessibility is limited. Different in vitro models have been utilized to estimate their potential ...bioavailability, but among other factors, the diversity of structures, chemical properties, and lability of chlorophylls hamper the investigations. By the first time, three extreme food matrices, one rich in fiber (vegetable puree), one rich in fat (virgin olive oil), and one liquid (fruit juice), have been assayed for chlorophyll bioaccessibility, controlling crucial variables. Chlorophyll polarity and food matrix were the determining factors, but surprisingly, chlorophyll bioaccessibility was affected during the application of the in vitro standardized protocol. Therefore, the present research has identified the reactions that can be biased during the estimation of chlorophyll bioaccessibility, defining a specific protocol in the function of chlorophyll structures.
The color of virgin olive oils, ranging from intense green to brown-yellow, is one of the main selection factors for consumers and a quality criterion in specific legislations. Such coloration is due ...to their chlorophyll content and depends on the composition of the olive fruit. Through analytical chemistry (HPLC-hrMS n ), biochemistry (enzymatic activity), and molecular biology (qRT-PCR) approaches, we have analyzed the origin of the differences in the chlorophyll content among several varieties of olive fruit throughout their ripening process. The higher chlorophyll biosynthetic capacity in olive fruits is due to the enzyme protochlorophyllide reductase, whereas chlorophyll degradation is accomplished through the stay-green and pheophytinase pathways. For the first time, the implication of chlorophyll dephytylase during the turnover of chlorophylls in fruit is shown to be responsible for the exclusive accumulation of dephytylated chlorophyll in Arbequina fruit. The multiomics results excluded the in vivo participation of chlorophyllase in chlorophyll degradation in olive fruits.
Chlorophylls and carotenoids are natural pigments that are present in our daily diet, especially with the increasing tendency towards more natural and healthy behaviors among consumers. As disturbed ...antioxidant homeostasis capacities seem to be implicated in the progress of different pathologies, the antioxidant properties of both groups of lipophilic compounds have been studied. The objective of this review was to analyze the state-of-the-art advances in this field. We conducted a systematic bibliographic search (Web of Science™ and Scopus®), followed by a comprehensive and critical description of the results, with special emphasis on highly cited and more recently published research. In addition to an evaluative description of the methodologies, this review discussed different approaches used to obtain a physiological perspective, from in vitro studies to in vivo assays using oxidative biomarkers. From a chemical viewpoint, many studies have demonstrated how a pigment's structure influences its antioxidant response and the underlying mechanisms. The major outcome is that this knowledge is essential for interpreting new data in a metabolic networks context in the search for more direct applications to health. A promising era is coming where the term "antioxidant" is understood in terms of its broadest significance.
•Cooking improves the chl recovery in green and brown seaweeds, but not in red algae.•Boiling is more drastic than microwaving for chl recovery only in green seaweeds.•Cooking decreases chl ...micellarization in brown and red but not in green seaweeds.•The chl bioaccessibility is higher in microwaved seaweeds than in boiling seaweeds.•Cooking enhances chl bioaccesibility in brown but decreases in red seaweeds.
Edible seaweeds are highly consumed food with a rich chlorophyll profile. Although seaweeds are mainly cooked ingested, the influence of cooking on the chlorophyll bioaccessibility remains unknown. In this research, cooked Nori, Sea Lettuce and Kombu were subjected to an in vitro digestion and following micellarization investigations. The processing of red seaweed does not affect the chlorophyll recovery, while cooking green and brown seaweeds implies an important increase in chlorophyll recovery after in vitro digestion. In this line, while cooking affects negatively the micellarization rate of chlorophyll derivatives in Nori and Kombu, it does not modify the micellarization in Sea Lettuce. Generally, the chlorophyll bioaccessibility of microwaved seaweeds is always higher than that of boiled ones. However, cooking improves the chlorophyll bioaccessibility in brown seaweeds, while decreases in red seaweeds. In conclusion, the characteristics of food matrix are the determinant factor on the chlorophyll bioaccessibility of cooked seaweeds.
Green Natural Colorants Viera, Isabel; Pérez-Gálvez, Antonio; Roca, María
Molecules (Basel, Switzerland),
01/2019, Letnik:
24, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Although there is no legal and clear definition of the term "natural food colorant", the market trends, and consequently industrial and commercial interest, have turned to foods with added natural ...pigments. This progressive substitution of artificial colorants has faced chemical complications with some colors, with a lack of stable green hues being one of them. Several strategies have been applied for green color stabilization in processed foods, from the formation of metallochlorophylls to the microencapsulation of green pigments. However, at present, the utilization of green coloring foodstuffs, which are considered an ingredient in the EU, seems to be the more successful solution for the market. Besides those topics, the present review aims to clarify the current confusion between the different chlorophyll compounds that form part of the authorized green food colorants. In this sense, legislations from different countries are compared. Finally, and in line with current concerns, the knowledge gathered so far in relation to the absorption, distribution, metabolism and excretion of all green natural food colorants is reviewed.
•Seaweed structure is the determining factor over chlorophylls in cooking process.•Chlorophyll transformations during cooking are more important in green seaweeds.•It has been studied by first time ...the impact of cooking on chlorophyll c.•Differences between microwave and boiling methods depend on seaweed classes.
Edible seaweeds are rich in chlorophyll pigments, although their modifications during cooking remain unknown. Consequently, the three most consumed seaweeds of different categories: Nori (Porphyra umbilicales), Sea Lettuce (Ulva sp.) and Kombu (Laminaria ochroleuca) were subjected to two cooking processes, boiling and microwaving. The chemical reactions of the chlorophyll pigments were determined by HPLC-UV/Vis. Besides the main chlorophyll transformations already described in fruits and vegetables (pheophytinisation and decarboxymethylation), the cooking of seaweeds caused a high level of oxidative reactions. Statistically, Nori was the most resistant algae to heating, while Sea Lettuce was the most labile seaweed. We report the thermal stability of c series for the first time, which were significantly less stable than a series in Kombu. Differences after microwaving and boiling methods depend mainly on the seaweed class. In conclusion, the seaweed structure is the main factor that determines the influence of cooking on the chlorophyll profile.
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•It’s the first time to find that oxidized chlorophylls are micellarizated.•Chlorophylls a and c are better micellarizated than chlorophyll b.•Nori chlorophylls are the most ...bioaccessible compared with those in Sea Lettuce and Kombu.•Pheophorbide c is the most Caco-2 cell absorbable chlorophyll derivative.•It’s the first time to find that chlorophyll oxidation occurs during cell absorption.
For the first time, the uptake of chlorophyll pigments from the main edible seaweeds (Nori, Sea Lettuce and Wakame) has been investigated. During the micellarisation process, dephytylated chlorophylls were favoured over phytylated chlorophylls (a and c series were favoured over b series and oxidised chlorophylls were preferentially micellarised). This is the first time chlorophyll b derivatives have been found to be resistant to the in vitro digestion of the food matrix, indicating they are also potentially absorbable by enterocytes during the ingestion of green vegetables and fruits. Nori chlorophylls stand out as the most bioaccessible, followed by those in Sea Lettuce and Kombu. During the Caco-2 cell absorption process, dephytylated chlorophyll derivatives were also favoured over phytylated ones, with pheophorbide c being the most absorbable chlorophyll pigment. It is also the first time that chlorophyll oxidation reactions have been observed during cell absorption. The uptake of chlorophyll derivatives from edible seaweeds resulted in Caco-2 cell lines with a chlorophyll profile dominated by dephytylated and oxidised derivatives.
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•The presence of salt in foods induces chlorophyll degradation during digestion.•Independently of food composition, final digesta are formed by 90% of pheophytins.•Foods with high ...carbohydrates favored pheophorbide stability.•Foods with high protein content favor pheophytin micellarization.•Pheophytins are more stable to digestion than pheophorbides.
Chlorophylls are ingested and effectively absorbed by our organism daily, but the effect of food composition on its bioaccessibility is unknown. Therefore, the present research analyses the chlorophyll bioaccessibility of ten commercial foods (guacamole, virgin olive oil, tortellini, basil hummus, creamed spinach, vegetable pasta, green tea chocolate, avocado and kiwi juices, and pesto sauce), selected based on their different nutritional (fat, fiber, protein, and carbohydrates) and chlorophyll composition and content. The most unexpected result was to correlate chlorophyll degradation during in vitro digestion with the salt content of the digested food. Surprisingly, independently of the foods’ nutritional composition or the chlorophyll content, the chlorophyll profile after in vitro digestion was formed by 90% pheophytins and 10% chlorophylls and pheophorbides. Such a pattern can only be modified when the ingested food contains a high proportion of pheophorbides (˃20%) that prevailed up to the mixed micelles.
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•Identified fifteen new chlorophyll compounds in green food colorants.•Eight of them were new structures while seven ones were only noted by synthesis.•Green coloring foodstuffs are ...analyzed for the first time.•Identified specific qualifier ions to distinguish among different chlorophylls.•Outlined chemical pathway responsible for chl modification during colorant production.
Consumers demand higher levels of food quality and safety, so food legislative organizations need full knowledge of food composition to develop regulations that guarantee quality and safety criteria. This is the context for green natural food colorants and the new category green “coloring foodstuffs”. We have exploited the capabilities of targeted metabolomics assisted by powerful software and algorithms to unravel the comprehensive chlorophyll composition in commercial samples of both colorant categories. With the aid of an in-house library, at first, seven new chlorophylls have been identified, among all the samples analyzed, providing data on their structural configuration. Next, taking advantage of an expert-curated database, eight more chlorophylls non-described previously have been found, which will be significant for the chemistry of chlorophylls. Finally, we have deciphered the sequence of chemical reactions that take place during the manufacturing of green food colorants and propose the whole pathway that explains the occurrence of the chlorophylls they contain.
Sodium copper chlorophyllins (SCC) are used worldwide to brightly color green foods as authorized food colorants, although their composition is only partially known. This study applied a combination ...of experimental and in silico techniques to describe the SCC profile in commercial colorant products and coloring foods. Different approaches have allowed identifying five new chlorophyll compounds in the food colorants besides the description of unique product ions able to distinguish among different chlorophyll isomers for the first time. In addition, a detailed isotope cluster analysis has revealed the formation of two new structures of copper chlorophyllins, featuring the copper in peripheral positions instead of the central pocket. Finally, a computational study of thermodynamic parameters and molecular descriptors has determined the factors responsible for the formation of the two main copper chlorophyllins present in the food colorants. This information will sustain alternative processing leading to SCC products with tailored composition.
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