Biosynthetic Pathway of Carotenoids (Capsanthin) in Capsicum [27] 

Contexts in source publication

Context 1

... molecular formula of capsanthin is C 40 H 56 O 3 ( Fig. 1) molecular weight is 584.871g mol , with density 1.012 g ml -1 and melting point is 177-178oC. Capsanthin has a long chain of conjugated double bond ending in one or two polar ketones efficiently absorb green light to give a red-orange hue. The hydroxyl group of ring structure is esterified with fatty acids into monoesters and diesters as well as appearing in the free form [10]. Capsanthin contains eleven conjugated double bonds, a conjugated keto group and a cyclopentane ring [11 , 12]. In the capsanthin molecule the double bond of the β-ionone ring is outside the polyene chain plane because of repulsion between the hydrogen atoms of the ring methyl groups and the hydrogen atoms of the polyene chain. While the carbonyl double bond in the other head group is very close to planarity with the polyene chain and no repulsion exist here [13]. Capsanthin is bioavailable in animal after feeding because capsanthin increases apolipoprotein A5 (apoA5) levels and lecithin cholesterol acyltransferase ( LCAT ) activity in plasma [15 , 16]. Capsanthin colors the egg yolk when fed to laying hens and the skin of broilers. The capsanthin 16 mg for laying hens and for skin pigmentation of hens 50mg capsanthin kg -1 feed is enough [17]. Pigmentation is also one of the important quality attributes of the aquatic animal for consumer acceptability. Carotenoids are responsible for pigmentation of muscle in food fish, skin color in ornamental fish [18] and abdomen and exoskeleton of Pacific white shrimp [19]. Carotenoids can boost antioxidant protection and immune strength and enrich the color of sexual ornaments like feathers in birds. Capsanthin is a fat soluble and enhances liposolubility by esterifying with short-chain saturated fatty acids. Capsanthin is distributed at the polar surface of lipoproteins and its clearance is faster than lycopen in the human body. Pérez-Gálvez, et al. [1] found that the bioavailability of capsanthin from paprika oleoresin is very low in human sample while oleoresin is a suitable sources for the pro-vitamin A carotenoids β-carotene and β-cryptoxanthin and the macular pigment zeaxanthin. The studies showed that dietary capsanthin was absorbed in to the body and distributed to plasma lipoprotein [20] and disappeared from plasma at faster rate than lycopene, while capsanthin is transported in to plasma lipoproteins in larger amounts and may be metabolized in the human body more rapidly than lycopene [21]. In a study of Maeda, et al. [22] obesity is related to various diseases, such as diabetes, hyperlipidemia, and hypertension. Adipocytokine, which is released from adipocyte cells, affects insulin resistance and blood lipid level disorders. Further, adipocytokine is related to chronic inflammation in obesity condition adipocyte cells. They have reported that paprika pigments, which contain high proportion of capsanthin, affect the liver and improve lipid disorders of the blood. They have further suggested that paprika (Capsanthin) ameliorates chronic inflammation in adipocytes caused by obesity, adjusts adipocytokine secretion and affect antimetabolic syndrome diseases. Capsanthin has greater anti-oxidative activity than other xanthophylls [23] which is because of its structure particularly the keto groups by lowering the autoxidation. Capsanthin is regarded as an antipromoter of cancer [24] and anti-tumor- promotion activity, even though it exhibits no pro-vitamin A activity. The epidemiological studies showed that capsanthin have inhibitory effect on colon carcinogenesis. So capsanthin rich foods are helpful to keep healthy [25]. Capsanthin also inhibit the growth and toxic productions of some poisonous fungus. Aflatoxin is among the most potent mutagenic and carcinogenic compounds produced by Aspergillus flavus in nature, which is globally health hazard to humans and animals. Capsanthin completely inhibited both the growth and toxin production of Aspergillus flavus [26] . Capsanthin is an end product of carotenoids in pepper carotenoids biosynthesis pathway (Fig. 2). The carotenoid (capsanthin) biosynthetic pathway starts from geranylgeranyl pyrophosphate (GGPP). Phytoene synthase (PSY) convert two molecules of GGPP to phytoene. Phytoene is desaturated into lycopene through ζ- carotene, which is catalyzed by two enzymes phytoene desaturase (PDS) and ζ-carotene desaturase (ZDS). The lycopene undergoes a cyclization reaction on both ends by lycopene β-cyclase (LCYB), thus producing β-carotene. β-carotene is then converted to β-cryptoxanthin, zeaxanthin and Antheraxanthin. The reactions are triggered by β-carotene hydroxylase (β-CH) and zeaxanthin epoxidase (ZE) respectively. Antheraxanthin is catalyzed by capsanthin- capsorubin synthase (CCS) to form Capsanthin (Fig. 2). The studies about the color of the pepper showed that the red, yellow or orange fruit color is control by three loci which are known as c1, c2 and y gene [28]. Kormos and Kormos [29] stated that the red pigment is determined by r + and yellow by r. They have mentioned that the precursor gene c + is required for the full expression of r + and r and in its absence the pigments are formed from the polyenes which accompany chlorophyll, while in the absence of c + and chlorophyll, only traces of pigment are formed. Later Lefebvre, et al. [30] find out that the red color is determined by the y+ dominant allele and yellow by y recessive allele. The red color is dominant over white and yellow in the F 1 cross of a red capsicum with a white and yellow capsicum producing only red F 1 progeny and it is controlled by a single gene corresponding to the y locus was subsequently determined to be the capsanthin- capsorubin synthase ( Ccs ) gene. The capsicum orange color is as result from the absence of the Ccs gene [31 , 32]. Thorup et al. [33] used the Ccs gene to determine the genotype of capsicums with different fruit colors at the y locus. They have find out that in BC1 segregants from a red × white cross, the red and peach-fruited progenies had the wild type allele at the Ccs locus, while the orange, yellow and white-fruited progenies had the mutant allele. Their experimental results showed that the capsanthin-capsorubin synthase ( Ccs ) locus, shown to cosegregate with Y, capsicum fruit color locus, mapped to capsicum chromosome 6. A full understanding of the regulation of the carotenoid (capsanthin) pathway, both structural and regulatory genes is necessary in order to manipulate carotenoid levels in crops. The studies showed that capsanthin is major pigment in the red fruits and synthesized by enzyme capsanthin-capsorubin synthase (CCS), which was purified from a membrane fraction of capsicum fruits by Bouvier, et al. [34]. Expression studies on selected carotenoid structural genes show that pigment-related transcripts are detected as the fruit begins to ripen. Phytoene synthase ( Psy ), phytoene desaturase ( Pds ), and capsanthin/capsorubin synthase ( Ccs ) genes expression are high with high levels of total carotenoid in pepper [3]. In immature capsicum fruits Capsanthin/capsorubin synthase ( Ccs ) gene does not express and â-carotene and lutein are the main carotenoids. Capsanthin/capsorubin synthase ( Ccs ) gene begins to express and increased gradually with color-changed period of capsicum fruits and at the same time, the lutein disappear and capsanthin accumulation begin. A deletion of Ccs detected in yellow capsicums was considered to be causal in the fruit phenotype [30]. The capsanthin capsorubin synthase ( Ccs ) gene is specifically expressed during chromoplast development in fruits accumulating ketocarotenoids, but not in mutants impaired [34] in biosynthetic pathway of capsanthin. The chromoplasts indeed differentiate from preexisting chloroplasts while chromoplast development process is entirely independent of the chloroplasts [35]. The transcripts of nuclear genes coding for chloroplast proteins, such as the major chlorophyll a/b-binding protein (encoded by cab) and the small subunit of ribulose-l, 5-bisphosphate carboxylase (encoded by rbcS) were detected by Kuntz et al. [36] in chromoplast-containing bell pepper leaves, whilst they disappeared in bell pepper fruit chromoplasts. According to Ha et al. [3] that capsicum yellow color at ripening is not because of deletion of Ccs gene but because of the nonsense-mediated transcriptional gene silencing of Ccs . Sequence analyses of the Ccs gene further revealed two structural mutations in yellow capsicums that may result in either a premature stop-codon or a frame-shift. So as a result the Ccs transcript is not detectable in yellow capsicums. A further analysis of the relationship between yellow ripe-fruit color and the capsanthin-capsorubin synthase ( Ccs ) gene in pepper ( Capsicum spp .) was studied by Li et al. [37]. They have identified a new ccs variant in the yellow fruit cultivar CK7 which has low genetic similarity to other yellow C. annuum varieties. In the coding sequence of this ccs allele, they have detected a premature ...

Context 2

... molecular formula of capsanthin is C 40 H 56 O 3 ( Fig. 1) molecular weight is 584.871g mol , with density 1.012 g ml -1 and melting point is 177-178oC. Capsanthin has a long chain of conjugated double bond ending in one or two polar ketones efficiently absorb green light to give a red-orange hue. The hydroxyl group of ring structure is esterified with fatty acids into monoesters and diesters as well as appearing in the free form [10]. Capsanthin contains eleven conjugated double bonds, a conjugated keto group and a cyclopentane ring [11 , 12]. In the capsanthin molecule the double bond of the β-ionone ring is outside the polyene chain plane because of repulsion between the hydrogen atoms of the ring methyl groups and the hydrogen atoms of the polyene chain. While the carbonyl double bond in the other head group is very close to planarity with the polyene chain and no repulsion exist here [13]. Capsanthin is bioavailable in animal after feeding because capsanthin increases apolipoprotein A5 (apoA5) levels and lecithin cholesterol acyltransferase ( LCAT ) activity in plasma [15 , 16]. Capsanthin colors the egg yolk when fed to laying hens and the skin of broilers. The capsanthin 16 mg for laying hens and for skin pigmentation of hens 50mg capsanthin kg -1 feed is enough [17]. Pigmentation is also one of the important quality attributes of the aquatic animal for consumer acceptability. Carotenoids are responsible for pigmentation of muscle in food fish, skin color in ornamental fish [18] and abdomen and exoskeleton of Pacific white shrimp [19]. Carotenoids can boost antioxidant protection and immune strength and enrich the color of sexual ornaments like feathers in birds. Capsanthin is a fat soluble and enhances liposolubility by esterifying with short-chain saturated fatty acids. Capsanthin is distributed at the polar surface of lipoproteins and its clearance is faster than lycopen in the human body. Pérez-Gálvez, et al. [1] found that the bioavailability of capsanthin from paprika oleoresin is very low in human sample while oleoresin is a suitable sources for the pro-vitamin A carotenoids β-carotene and β-cryptoxanthin and the macular pigment zeaxanthin. The studies showed that dietary capsanthin was absorbed in to the body and distributed to plasma lipoprotein [20] and disappeared from plasma at faster rate than lycopene, while capsanthin is transported in to plasma lipoproteins in larger amounts and may be metabolized in the human body more rapidly than lycopene [21]. In a study of Maeda, et al. [22] obesity is related to various diseases, such as diabetes, hyperlipidemia, and hypertension. Adipocytokine, which is released from adipocyte cells, affects insulin resistance and blood lipid level disorders. Further, adipocytokine is related to chronic inflammation in obesity condition adipocyte cells. They have reported that paprika pigments, which contain high proportion of capsanthin, affect the liver and improve lipid disorders of the blood. They have further suggested that paprika (Capsanthin) ameliorates chronic inflammation in adipocytes caused by obesity, adjusts adipocytokine secretion and affect antimetabolic syndrome diseases. Capsanthin has greater anti-oxidative activity than other xanthophylls [23] which is because of its structure particularly the keto groups by lowering the autoxidation. Capsanthin is regarded as an antipromoter of cancer [24] and anti-tumor- promotion activity, even though it exhibits no pro-vitamin A activity. The epidemiological studies showed that capsanthin have inhibitory effect on colon carcinogenesis. So capsanthin rich foods are helpful to keep healthy [25]. Capsanthin also inhibit the growth and toxic productions of some poisonous fungus. Aflatoxin is among the most potent mutagenic and carcinogenic compounds produced by Aspergillus flavus in nature, which is globally health hazard to humans and animals. Capsanthin completely inhibited both the growth and toxin production of Aspergillus flavus [26] . Capsanthin is an end product of carotenoids in pepper carotenoids biosynthesis pathway (Fig. 2). The carotenoid (capsanthin) biosynthetic pathway starts from geranylgeranyl pyrophosphate (GGPP). Phytoene synthase (PSY) convert two molecules of GGPP to phytoene. Phytoene is desaturated into lycopene through ζ- carotene, which is catalyzed by two enzymes phytoene desaturase (PDS) and ζ-carotene desaturase (ZDS). The lycopene undergoes a cyclization reaction on both ends by lycopene β-cyclase (LCYB), thus producing β-carotene. β-carotene is then converted to β-cryptoxanthin, zeaxanthin and Antheraxanthin. The reactions are triggered by β-carotene hydroxylase (β-CH) and zeaxanthin epoxidase (ZE) respectively. Antheraxanthin is catalyzed by capsanthin- capsorubin synthase (CCS) to form Capsanthin (Fig. 2). The studies about the color of the pepper showed that the red, yellow or orange fruit color is control by three loci which are known as c1, c2 and y gene [28]. Kormos and Kormos [29] stated that the red pigment is determined by r + and yellow by r. They have mentioned that the precursor gene c + is required for the full expression of r + and r and in its absence the pigments are formed from the polyenes which accompany chlorophyll, while in the absence of c + and chlorophyll, only traces of pigment are formed. Later Lefebvre, et al. [30] find out that the red color is determined by the y+ dominant allele and yellow by y recessive allele. The red color is dominant over white and yellow in the F 1 cross of a red capsicum with a white and yellow capsicum producing only red F 1 progeny and it is controlled by a single gene corresponding to the y locus was subsequently determined to be the capsanthin- capsorubin synthase ( Ccs ) gene. The capsicum orange color is as result from the absence of the Ccs gene [31 , 32]. Thorup et al. [33] used the Ccs gene to determine the genotype of capsicums with different fruit colors at the y locus. They have find out that in BC1 segregants from a red × white cross, the red and peach-fruited progenies had the wild type allele at the Ccs locus, while the orange, yellow and white-fruited progenies had the mutant allele. Their experimental results showed that the capsanthin-capsorubin synthase ( Ccs ) locus, shown to cosegregate with Y, capsicum fruit color locus, mapped to capsicum chromosome 6. A full understanding of the regulation of the carotenoid (capsanthin) pathway, both structural and regulatory genes is necessary in order to manipulate carotenoid levels in crops. The studies showed that capsanthin is major pigment in the red fruits and synthesized by enzyme capsanthin-capsorubin synthase (CCS), which was purified from a membrane fraction of capsicum fruits by Bouvier, et al. [34]. Expression studies on selected carotenoid structural genes show that pigment-related transcripts are detected as the fruit begins to ripen. Phytoene synthase ( Psy ), phytoene desaturase ( Pds ), and capsanthin/capsorubin synthase ( Ccs ) genes expression are high with high levels of total carotenoid in pepper [3]. In immature capsicum fruits Capsanthin/capsorubin synthase ( Ccs ) gene does not express and â-carotene and lutein are the main carotenoids. Capsanthin/capsorubin synthase ( Ccs ) gene begins to express and increased gradually with color-changed period of capsicum fruits and at the same time, the lutein disappear and capsanthin accumulation begin. A deletion of Ccs detected in yellow capsicums was considered to be causal in the fruit phenotype [30]. The capsanthin capsorubin synthase ( Ccs ) gene is specifically expressed during chromoplast development in fruits accumulating ketocarotenoids, but not in mutants impaired [34] in biosynthetic pathway of capsanthin. The chromoplasts indeed differentiate from preexisting chloroplasts while chromoplast development process is entirely independent of the chloroplasts [35]. The transcripts of nuclear genes coding for chloroplast proteins, such as the major chlorophyll a/b-binding protein (encoded by cab) and the small subunit of ribulose-l, 5-bisphosphate carboxylase (encoded by rbcS) were detected by Kuntz et al. [36] in chromoplast-containing bell pepper leaves, whilst they disappeared in bell pepper fruit chromoplasts. According to Ha et al. [3] that capsicum yellow color at ripening is not because of deletion of Ccs gene but because of the nonsense-mediated transcriptional gene silencing of Ccs . Sequence analyses of the Ccs gene further revealed two structural mutations in yellow capsicums that may result in either a premature stop-codon or a frame-shift. So as a result the Ccs transcript is not detectable in yellow capsicums. A further analysis of the relationship between yellow ripe-fruit color and the capsanthin-capsorubin synthase ( Ccs ) gene in pepper ( Capsicum spp .) was studied by Li et al. [37]. They have identified a new ccs variant in the yellow fruit cultivar CK7 which has low genetic similarity to other yellow C. annuum varieties. In the coding sequence of this ccs allele, they have detected a premature stop codon derived from a C to G change, as well as a downstream frame-shift caused by a 1-bp nucleotide deletion. Guzman et al. [14] cloned and sequenced four carotenoid biosynthetic genes of Psy, Lcyb, CrtZ-2 and Ccs of capsicum cultivars (Valencia, Orange Grande, Oriole, Fogo, Dove, Canary and NuMex Sunset). They observed a new variant of Ccs by observing that Lcyb and Ccs contained no introns but did exhibit polymorphisms resulting in amino acid changes. The Lang et al. [31] find out that in orange color of capsicum phenotype the deletion of amino terminus of CCS is consider being causal. They have crossed red fruit (cv. 227 long) and orange fruit (cv. Ms GTY-1) pepper and observed a polymorphism of Ccs ...