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. 2023 Sep 28;21(10):514. doi: 10.3390/md21100514

Table 2.

Astaxanthin: Summary of its presence in various organisms and its origin.

Taxon Scientific Name Common Name Astaxanthin Reference
Form † Stereoisomer
(3R,3′R, meso, 3S,3′S)		 Content (mg/100 g) Origin
Bacteria, Prtoteobacteria, Alphaproteobacteria
Paracoccus carotinifaciens
(w/. mutation)		 PanaFerd-AX Free form 3S,3′S 2180
(50.2% of total Car)		 De novo
synthesis		 [329,330]
Paracoccus sp. strain N81106
(NBRC 101723)
(Agrobacterium auranticum)
(w/. mutation)		 N/A Free form and glycoside 3S,3′S ~800
(63.2% of total Car)		 De novo
synthesis		 [331]
Brevundimonas sp. M7
(w/. mutation)		 N/A Free form ** 3S,3′S ** 130 De novo
Synthesis **		 [186]
Sphingomonas astaxanthinifaciens
TDMA-17		 N/A Free form 3S,3′S ** 96.0
(34.3% of total Car)		 De novo
Synthesis **		 [182]
Paracoccus haeundaensis
KCCM 10460
(Co-culture w/. Lactic Acid Bacteria) 		N/A Free form 3S,3′S ** 82.1 De novo
synthesis		 [332]
Paracoccus bogoriensis BOG6T (DSM16578, LMG2279) N/A Free form 3S,3′S 40
(10.8% of total Car)		 De novo
synthesis		 [183]
Brevundimonas spp. N/A Free form ** 3S,3′S ** 2.8~36.5 De novo
Synthesis **		 [186]
Sphingomicrobium astaxanthinifaciens
CC-AMO-30B		 N/A Free form 3S,3′S ** 4.0 De novo
Synthesis **		 [185]
Brevundimonas sp. strain SD212
(NBRC 101024)		 N/A Free form 3S,3′S N/A
(9.9% of total Car)		 De novo
synthesis		 [181]
Archaea
Halobacterium salinarium NRC-1 N/A Free form ‡ N/D 26.5
(c.a.73% of total Car)		 De novo
Synthesis *		 [203]
Haloarcula hispanica ATCC 33960 N/A Free form ‡ N/D 1.7
(c.a.1.3% of total Car)		 De novo
Synthesis* 		[203]
Eukaryota, Fungi
Xanthophyllomyces dendrorhous
(ATCC SD 5340)		 Phaffia Yeast Free form 3R,3′R 723.5~1247.8
(c.a. 73% of total Car)		 De novo
synthesis		 [327,333]
Eukaryota, Plantae
Adonis amurensis
(Reddish flower varieties)		 Amur adonis,
pheasant’s eye		 Fatty acid esters 3S,3′S ** ~3310
(in upper red part of petal)
(c.a. 70% of total Car)		 De novo
Synthesis **		 [334]
Adonis annua Autumn pheasant’s eye, blooddrops Fatty acid esters 3S,3′S 120~1000
(in dry petal)
(c.a. 75% of total Car)		 De novo
Synthesis **		 [17,50]
Adonis aestivalis Summer pheasant’s eye Fatty acid esters 3S,3′S 166
(in wet petal)
(87.4% of total Car)		 De novo
synthesis		 [265]
Eukaryota, Plantae, Chlorophyta
Haematococcus lacustris Haematococcus
pluvilialis,
Haematococcus algae		 Fatty acid esters 3S,3′S ~9800
(in red cyst)
(>90% of total Car)		 De novo
synthesis		 [64,328]
Neochloris wimmeri CCAP-213/4 N/A Fatty acid esters 3S,3′S ** ~1920
(c.a 85% of total Car)		 De novo
Synthesis **		 [227,228,232]
Asterarcys quadricellulare PUMCC 5.1.1 N/A N/A 3S,3′S** ~1550
(c.a 13% of total Car)		 De novo
Synthesis **		 [236]
Protosiphon botryoides SAG-731/1a N/A Fatty acid esters 3S,3′S** ~1430
(c.a 80% of total Car)		 De novo
Synthesis **		 [227,228]
Scotiellopsis oocystiformis
SAG-277/1		 N/A Fatty acid esters 3S,3′S ** ~1090
(c.a 70% of total Car)		 De novo
Synthesis **		 [227,228]
Chlorococcum sp. N/A Fatty acid esters 3S,3′S ** ~c.a. 700
(c.a. 32% of total Car)		 De novo
Synthesis **		 [335,336,337]
Chlorella zofingiensis SAG-211/14 Chlorella Fatty acid esters 3S,3′S ** ~680
(c.a. 75% of total Car)		 De novo
Synthesis **		 [227,228]
Scenedesmus vacuolatus
SAG-211/15 		N/A Fatty acid esters 3S,3′S ** ~270
(40–50% of total Car)		 De novo
Synthesis **		 [227,228]
Chlamydocapsa spp.
Strain 101-99/R2		 N/A N/A 3S,3′S ** ~44.4
(20.3% of total Car)		 De novo
Synthesis **		 [338]
Neochloris oleoabundans UTEX#1185 N/A Fatty acid esters 3S,3′S ** N/A De novo
Synthesis **		 [232]
Dysmorphococcus globosus-HI N/A Free form/
Fatty acid esters		 3S,3′S ** ~517,090?? De novo
Synthesis **		 [243]
Eukaryota, Chromista, Bigyra, Labyrinthulomycetes
Aurantiochytrium sp. RH-7A-7
(w/. mutation)		 Labyrinthulomycetes N/A 3S,3′S ** -470
(c.a. 85% of total Car)		 De novo
Synthesis *		 [218]
Thraustochytrium sp. CHN-3
(FERM P-18556)		 Labyrinthulomycetes Free form ** 3S,3′S ** ~280
(~60% of total Car)		 De novo
Synthesis *		 [339]
Aurantiochytrium sp. KH-10 Labyrinthulomycetes Fatty acid esters/
Free form		 3S,3′S ** ~81
(28% of total Car)		 De novo
Synthesis *		 [340]
Thraustochytrium sp. CHN-1 Labyrinthulomycetes Free form 3S,3′S 50
(c.a. 50% of total Car)		 De novo
Synthesis *		 [341,342]
Eukaryota, Chromista, Gyrista , Eustigmatales
Nannochloropsis gaditana strain S4
(w/. mutation)		 Nannochloropsis Free form 3S,3′S? ~219
(14.4% of total Car)		 De novo
Synthesis		 [219]
Nannochloropsis oculata Nannochloropsis Free form 3S,3′S? 3.4 ng/106 cells De novo
Synthesis		 [343]
Nannochloropsis salina Nannochloropsis Free form 3S,3′S? 9.6 ng/106 cells De novo
Synthesis		 [343]
Eukaryota, Excavata, Euglenozoa
Euglena sanguinea Euglena Fatty acid
esters/free		 3S,3′S ~1.9
(80% of total Car)		 De novo
Synthesis		 [256,344]
Trachelomonas volvocina Euglena Fatty acid esters/
Free form		 3S,3′S * N/A De novo
Synthesis		 [215]
Animals (Invertebrate), Coelenterata
Velella velella By-the-wind sailor
(Jerry fish)		 Free form Mixtures of
stereoisomers		 N/A Accumulated from dietary Crustaceans [98]
Aurelia aurita (Jerry fish) Fee form/
Fatty acid esters (minor)		 N/A 12.2
(c.a.67% of total Car)		 N/A [279]
Metridium senile var. fimbriatum Frilled anemone
(Sea anemone)		 Fatty acid esters
(in ovary) 		Mixtures of
stereoisomers		 N/A Oxidative metabolite of
β-carotene		 [345,346]
Corynactis californica Strawberry anemone
(Sea anemone)		 Fatty acid
esters		 N/A N/A Oxidative
metabolite of
β-carotene		 [347]
Animals (Invertebrate), Mollusca , Gastropoda
Clione limacina Sea angel Free form 3S,3′S 0.051
(1.1% of total Car)		 Oxidaive
metabolite of
zeaxanthin		 [348]
Paedoclione doliiformis Sea angel Free form 3S,3′S 0.8
(5.5% of total Car)		 Oxidaive
metabolite of
zeaxanthin		 [348]
Semisulcospira libertina Terestorial Snail
(Kawanina in Japanese)		 Free form 3S,3′S 0.2
(6.5% of total Car)		 Oxidaive metabolite of zeaxanthin [349]
Fushinus perplexu Spindle shell Free form 3S,3′S 0.2
(4.0% of total Car)		 Oxidative
metabolite of
β-carotene		 [350]
Pomacea canaliculata Apple snail Free form 3S,3′S 5.0 in gonad, 2.31 in egg
(~75% of total Car)		 Oxidative
metabolite of
β-carotene		 [351]
Animals (Invertebrate), Mollusca , Cephalopoda
Octopus vulgaris Common octopus Fatty acid esters/
Free form		 Mixtures of stereoisomers
(46:22:32)		 3.2 in liver
(c.a.80% of total Car)		 Accumulated from dietary crustaceans [288]
Watasenia scintillans Firefly squid Fatty acid esters/
Free form		 Mixtures of stereoisomers
(40:6:54)		 5.0 in liver
(>90% of total Car)		 Accumulated from dietary crustaceans [288]
Animals (Invertebrate), Mollusca, Polyplacophora
Placiphorella japoonica Chiton Free form Mixtures of stereoisomers
(5:3:2)		 1.25
(~34% of total Car)		 Oxidative
metabolite of
β-carotene		 [352]
Acanthochitona defilippii Chiton Free form 3S,3′S 1.55 in gonad
(~4.0% of total Car)		 Oxidative
metabolite of
β-carotene		 [352]
Liolophura japonica Chiton Free form 3S,3′S 0.8 in viscera
(~10% of total Car)		 Oxidative
metabolite of
β-carotene		 [352]
Animals (Invertebrate), Echinodermata
Peronella japonica Sea urchin Free form Mixtures of stereoisomers
(3:7:90)		 ~3.0 in gonad
(c.a.43% of total Car)		 Oxidative
metabolite of
β-carotene		 [301]
Asteria pectinifera Starfish Free form Mixtures of stereoisomers
(50:25:25)		 ~1.35
(% of total Car)		 Oxidative
metabolite of
β-carotene		 [305]
Asterias amurensis Starfish Free form Mixtures of stereoisomers
(48:25:27)		 ~4.64
(% of total Car)		 Oxidative
metabolite of
β-carotene		 [305]
Animals (Invertebrate), Arthropoda, Crustacea, Decapoda (Lobsters, rock lobsters and crawfishes)
Procambarus clarkii Louisiana crawfish Fatty acid ester/
Free form		 Mixtures of stereoisomers 7.9–19.8 in carapace Oxidative
metabolite of
β-carotene		 [353]
Pontastacus leptodactylus
(Astacus leptodactylus)		 Turkish crayfish Fatty acid esters
/Free form		 Mixtures of stereoisomers ** 5.0 in carapace
0.13 in muscle
0.98 in intestine
(82.5% of total Car)		 Oxidative
metabolite of
β-carotene **		 [354]
Panulirus japonicus Japanese Spiny Lobster
(Ise-ebi)		 Free form/
Fatty acid esters		 Mixtures of stereoisomers
(20:20:56)		 3.3 in carapace
(65% of total Car)		 Oxidative
metabolite of
β-carotene		 [355]
Animals (Invertebrate), Arthropoda, Crustacea, Copepoda
Tigriopus californicus Red marine copepod Free form
(major)		 3S,3′S
(major)		 ~423 Oxidative
metabolite of
β-carotene		 [290,356]
Animals (Invertebrate), Arthropoda, Crustacea, Eucarida
Euphausia superba Antarctic krill Fatty acid esters/
Free form		 3R,3′R
(Major, ~70%)		 ~566 in eye Oxidative
metabolite of
β-carotene ?		 [291,357]
Euphausia pacifica Pacific krill (Isada) Fatty acid esters/
Free form		 3R,3′R
(Major)		 ~ 252 in eye Oxidative
metabolite of
β-carotene ?		 [357,358]
Animals (Invertebrate), Arthropoda, Crustacea, Decapoda (Prawns and shrimps) ***
Pandalus borealis Atlantic shrimp
(Northern prawn)		 Fatty acid esters/
Free form		 Mixtures of
stereoisomers
(25:52:23) 		~28.48 in carapace Oxidative
metabolite of
β-carotene		 [62,359,360]
Penaeus japonicus Japanese tiger prawn
(Kuruma-ebi)		 Fatty acid esters/
Free form		 Mixtures of stereoisomers
(12:40:48)		 ~13 in carapace Oxidative
metabolite of
β-carotene		 [361,362]
Penaeus semisulcatus Green tiger prawn Fatty acid esters/
Free form		 Mixtures of stereoisomers
(19:44:57)		 ~15.6 in carapace Oxidative
metabolite of
β-carotene		 [362]
Penaeus monodon Black tiger prawn Fatty acid esters/
Free form		 Mixtures of stereoisomers
(16:43:41)		 ~7.3 in carapace Oxidative
metabolite of
β-carotene		 [362]
Litopenaeus vannamei Whiteleg shrimp Fatty acid esters/
Free form		 Mixtures of stereoisomers
(23:44:32)		 ~5.8 in carapace Oxidative
metabolite of
β-carotene		 [362]
Metapenaeus joyneri Shiba shrimp Fatty acid esters/
Free form		 Mixtures of stereoisomers
(14:46:40)		 ~3.3 in carapace Oxidative
metabolite of
β-carotene		 [362]
Animals (Invertebrate), Arthropoda, Crustacea, Decapoda , Brachyura (Crabs) ***
Chionoecetes japonicus Red snow crab
(Beni-zuwai crab)		 Fatty acid esters/
Free form **		 Mixtures of stereoisomers ** ~23 in carapace
(with demineralization treatment)		 Oxidative metabolite
of β-carotene?		 [363]
Chionoecetes opilio Snow crab
(Zuwai crab)		 Fatty acid esters/
Free form		 Mixtures of stereoisomers? ~11.9 in carapace
(~91.7% of total Car)		 Oxidative metabolite
of β-carotene?		 [364]
Callinectes sapidus Blue crab Fatty acid esters/
Free form		 Mixtures of stereoisomers? ~9.8
(with demineralization treatment)		 Oxidative metabolite
of β-carotene?		 [365]
Cancer pagurus Brown crab Fatty acid esters/
Free form		 Mixtures of stereoisomers
(56:24:20)		 0.37 in carapace Oxidative metabolite
of β-carotene?		 [366,367]
Animals (Invertebrate), Arthropoda, Crustacea, Decapoda (Others) ***
Paralithodes brevipes Hanasaki crab Fatty acid esters/
Free form		 Mixtures of
stereoisomers
(26:9:6)		 ~2.4 in carapace
(~39.9% of total Car)		 Oxidative
metabolite of
β-carotene		 [368]
Paralithodes camtschaticus Red king crab Fatty acid esters/
Free form		 Mixtures of
stereoisomers
(45–55:7–19:27–48)		 ~0.35 in carapace
(~97% of total Car)		 Oxidative
metabolite of
β-carotene		 [277,369]
Cervimunida princeps Squat lobster Fatty acid esters/
Free form		 Mixtures of
stereoisomers
(26:9:65)		 ~ 0.45 in carapace
(~100% of total Car)		 Oxidative
metabolite of
β-carotene		 [369]
Upogebia major Japanese mud shrimp Fatty acid esters/
Free form		 Mixtures of stereoisomers
(72:21:7)		 ~ 0.25 in carapace
(~100% of total Car)		 Oxidative
metabolite of
β-carotene		 [369]
Birgus latro Coconut crab Fatty acid esters/
Free form		 Mixtures of stereoisomers
(9:41:50)		 ~ 0.3 in carapace
(~96% of total Car)		 Oxidative
metabolite of
β-carotene		 [370]
Asellus aquaticus Isopoda Free form/
Fatty acid esters?		 N/A ~0.52
(~37.5% of total Car)		 Oxidative
metabolite of
β-carotene?		 [371]
Pleuroncodes planipes Red crab langostilla Fatty acid esters/
Free form		 Mixtures of stereoisomers
(3–4:1:3–4)		 N/A Oxidative
metabolite of
β-carotene?		 [372]
Animals (Invertebrate), Arthropoda, Arachnida, Acari
Balaustium murorum Red velvet mite Free form/
Fatty acid esters		 3S,3′S ** ~61,530 mg/
100 g protein
(60% of total Car)		 Oxidative metabolite of zeaxanthin (De novo
Synthesis **)		 [373]
Panonychus citri Citrus red mite Fatty acid esters 3S,3′S ** ~263 mg/
100 g protein
(42.5% of total Car)		 De novo
Synthesis **		 [374]
Tetranychus kanzawai Kanzawa spider mite Fatty acid esters 3S,3′S ** Undefined De novo
Synthesis		 [375]
Tetranychus urticae Two-spotted spider mite Fatty acid esters 3S,3′S ** Undefined De novo
Synthesis		 [296,376]
Eylais hamata Hydracarina Free form/
Fatty acid esters (minor)		 N/A 12.2
(c.a.67% of total Car)		 N/A [377]
Eylais extendens Hydracarina N/A N/A Undefined
(c.a.70% of total Car)		 N/A [378]
Schizonobia sycophanta Parasite mite Fatty acid ester 3S,3′S Undefined
(30% of total Car)		 De novo
Synthesis **		 [49,289]
Animals (Invertebrate), Arthropoda, Arachnida, Araneae
Trichonephila clavata Arachnida spider ?? Mixtures of
stereoisomers
(2:1:1) 		0.02
(1.9% of total Car)		 Oxidative metabolite of β-carotene [299]
Animals (Invertebrate), Arthropoda, Insecta
Locusta migratoria Migratory locust Free form Mixtures of
stereoisomers
(2:1:1)		 0.25
in brown form
(12.5% of total Car)		 Oxidative metabolite of β-carotene [16,293]
Aiolopus thalassinus tamulus Grasshopper Free form Mixtures of
stereoisomers
(2:1:1)		 0.09
in brown form
(3.0% of total Car)		 Oxidative metabolite of β-carotene [293]
Schistocerca gregaria Desert locust Free form Mixtures of
stereoisomers *		 N/A Oxidative metabolite of β-carotene [16]
Animals (Vertebrate), Fish (Salmonidae)
Oncorhynchus nerka
(Wild, anadromous form)		 Sockeye salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers
(depending on AX source)		 2.6–3.8 in muscle
in egg
(% of total Car)		 Accumulated from dietary crustaceans [308]
Oncorhynchus nerka
(Wild, non-anadromous form)		 Kokanee salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers
(depending on AX source)		 −0.8 in muscle
0.4–2.8 in skin
−1.1 in golnad
(−94% of total Car)		 Accumulated from dietary crustaceans [379,380]
Oncorhynchus kisutch Coho salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers
(depending on AX source)		 1.0–2.1 in muscle
in egg
(% of total Car)		 Accumulated from dietary crustaceans [308]
Salvelinus alpinus
(Wild)		 Arctic char Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers
(depending on AX source)		 0.86 in muscle
in egg
(−30% of total Car)		 Accumulated from dietary crustaceans [308,381]
Salmo salar
(Wild)		 Atlantic salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers
(depending on AX source)		 0.6–0.8 in muscle
in egg
(% of total Car)		 Accumulated from dietary crustaceans [308,382]
Oncorhynchus keta Chum salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mainly 3S,3′S
(in ovary)		 0.1–0.5 in muscle
−0.7 in egg
0.1 in skin (male)
(4.8–90% of total Car)		 Accumulated from dietary crustaceans [28,29,308,383]
Oncorhynchus gorbuscha Pink salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers 0.4–0.7 in muscle
in egg
(% of total Car)		 Accumulated from dietary crustaceans [308]
Oncorhynchus tshawytscha Chinook salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers 0.54 in muscle
in egg
(% of total Car)		 Accumulated from dietary crustaceans [308]
Oncorhynchus masou
(Wild, anadromous form)		 Masu salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers 0.3–0.8 in muscle
0.03–0.8 in skin
0.7–1.7 in egg
(1.9–80% of total Car)		 Accumulated from dietary crustaceans [308,380,384]
Oncorhynchus masou ishikawae
(Wild, anadromous form)		 Red-spotted masu salmon Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of stereoisomers 0.2 in muscle
trace in skin
N/D in egg
(1.9–68.5% of total Car)		 Accumulated from dietary crustaceans [380]
Oncorhynchus masou rhodurus Biwa trout Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of
stereoisomers		 0.2 in muscle
−0.1 in skin
(3.2–58.3% of total Car)		 Accumulated from dietary crustaceans [380]
Oncorhynchus mykiss
(Wild, pigmented phenotype)		 Rainbow trout Free form
(muscle/egg)/
Fatty acid esters
(skin)		 Mixtures of
stereoisomers		 trace in muscle
0.8 in skin
trace in egg
(1.9–42.3% of total Car)		 Accumulated from dietary crustaceans [385]
Animals (Vertebrate), Fish (Non-Salmonidae )
Sebastolobus macrochir Broadbanded thornyhead
(Kichiji rockfish)		 Fatty acid esters
(skin)		 N/A 26 in skin
(>90% of total Car)		 Accumulated from dietary crustaceans
or
Oxidative metabolite of β-carotene/
zeaxanthin?		 [386]
Plectropomus leopardus Coral trout
(Suziara)		 Fatty acid esters/
Free form
(skin)		 Mixtures of stereoisomers
(13:7:80)		 19.5 in skin
(84.8% of total Car)		 Accumulated from dietary crustaceans
or
Oxidative
metabolite of
β-carotene/
zeaxanthin?		 [387]
Epinephelus fasciatus Blacktip grouper
(Akahata)		 Fatty acid esters
(skin)		 N/A 2.27 in skin
(74% of total Car)		 Accumulated from dietary crustaceans
or
Oxidative
metabolite of
β-carotene/
zeaxanthin?		 [386]
Beryx splendens Splendid alfonsino
(Kinmedai)		 Fatty acid esters
(skin)		 Mixtures of stereoisomers 0.9 in skin
(c.a. 100% of total Car)		 Accumulated from dietary crustaceans
or
Oxidative
metabolite of
β-carotene/
zeaxanthin?		 [386]
Pagrus malor Red sea bream
(Madai)		 Fatty acid esters
(skin)		 Mixtures of stereoisomers
(38:0:62)		 ~2 in skin (wild)
0.25 in skin (firmed w/o. AX) /
0.98 (firmed with. AX)
(~c.a 45% of total Car)		 Accumulated from dietary crustaceans and supplementary pigment [277,386,388]
Carassius auratus Goldfish
(Kingyo/Hibuna)		 Free/ Fatty acid esters
(skin) 		3S,3′S 0.58 (whole body)
(~47% of total Car)		 Oxidative metabolite of
β-carotene/
zeaxanthin		 [307]
Branchiostegus japonicus Red tilefish
(Red amadai)		 Fatty acid esters
(skin)		 Mixtures of stereoisomers
(24:24:52)		 0.39 in skin
(35.8% of total Car)		 Accumulated from dietary crustaceans [389]
Animals (Vertebrate), Amphibian
Cynops pyrrhogaster Japanese newt Free form/
Fatty acid esters		 N/A 4.55 in skin
(c.a.21% of total Car)		 Oxidative
metabolite
of
β-carotene/
zeaxanthin		 [309]
Salamandra salamandra Fire salamander Free form/
Fatty acid esters		 N/A 0.23
(37.5% of total Car)		 Oxidative
metabolite
of
β-carotene/
zeaxanthin		 [390]
Lissotriton vulgaris
(Triturus vulgaris)		 Smooth newt/common newt Free form N/A 0.1
(−23.5% of total Car)		 Oxidative
metabolite
of
β-carotene/
zeaxanthin		 [390]
Ranitomeya sirensis Sira poison frog Free form/
Fatty acid esters ?		 N/A N/A
(-c.a. 40% of total Car)		 Oxidative
metabolite
of
β-carotene/
zeaxanthin		 [294]
Bufo bufo Common toad Free form/
Fatty acid esters		 N/A N/D in muscle and liver
0.02 in skin
0.35 in intestine
(25.8–57.4% of total Car)
0.23 in gonads
(95.8% of total Car)		 Oxidative
metabolite
of
β-carotene/
zeaxanthin		 [390]
Bufotes viridis
(Bufo viridis) 		European green toad Free form/
Fatty acid esters		 N/A N/D in muscle and liver
0.02 in skin
0.35 in intestine
(25.8–57.4% of total Car)
0.23 in gonads
(95.8% of total Car)		 Oxidative
metabolite
of
β-carotene/
zeaxanthin		 [391]
Pelobates fuscus European common spadefoot toad Free form N/A 1.1 in liver
(19.6% of total Car)		 Oxidative
metabolite
of
β-carotene/
zeaxanthin **		 [390]
Melanophryniscus rubriventris (Aposematic poison toad) N/A
(Free form/ ester form?)		 N/A Undefined Oxidative
metabolite of
β-carotene **		 [392]
Animals (Invertebrate), Reptile
Chlamydosaurus kingii.
(the western red-frilled form)		 Frillneck lizard N/A
(Free form?)		 N/A Undefined Oxidative
metabolite of
β-carotene		 [312]
Chrysemys picta Painted turtle N/A N/A c.a 0.11 in leg skin Oxidative
metabolite of
β-carotene		 [393]
Trachemys scripta Red-eared slider N/A N/A c.a 0.06
in skin around eye spot		 Oxidative
metabolite of
β-carotene		 [393]
Animals (Invertebrate), Aves ***
Lagopus lagopus scoticus Red grouse Free form/
Fatty acid esters		 N/A 317.8 in combs
N/D in plasma
(-c.a.81.6% of total Car)		 Oxidative metabolite of β-carotene [394]
Pygoscelis papua Gentoo penguins Free form N/A 2.19 in blood,
breeding adults and chicks		 Accumulated from dietary crustaceans, fishes [395,396]

The respective number was quoted from the reference(s), and it may vary depending on the collection location and season.†, the presence of binding forms to carotenoproteins would not be mentioned in this table; ‡, the identification method of the compounds remains uncertain; *, the biosynthetic pathways have not been fully characterized; **, based on the information on close species/genus; N/A; not available; N/D; not detected.*** Since astaxanthin is diversely found in the skin, feathers, and retinas of birds, only the characteristic reports are described. ?; based on the information on close taxa. For the details of distribution in avian species, see the other review [314].