Table 2

Enzyme	Identified Species	Habitat	Optimum Temperature (°C)	Reference
Pepsin I	Sardine	Warm water	55	Noda and Murakami [70]
Pepsin II	Sardine	Warm water	40	Noda and Murakami [70]
Pepsin I	Arctic capelin	Cold water	38	Gildberg and Raa [48
Pepsin II	Arctic capelin	Cold water	43	Gildberg and Raa [48]
Pepsin I	European eel	Warm water	40	Wu et al. [52]
Pepsin II	European eel	Warm water	40	Wu et al. [52]
Pepsin III	European eel	Warm water	35	Wu et al.[52]
Pepsin	Greenland cod	Cold water	30	Squires et al. [61]
Pepsin	Arctic cod	Cold water	32	Haardet al. [72]
Pepsin	Polar cod	Cold water	37	Arunchalam and Haard [76]
Pepsin I	Atlantic cod	Cold water	40	Gildberg [58]
Pepsin II	Atlantic cod	Cold water	40	Gildberg [58]
Pepsin	Palometa	Warm water	37	Pavliskoet al. [73]
Pepsin I	Sea bream	Warm watera	45	Zhou et al. [51]
Pepsin II	Sea bream	Warm water	50	Zhou et al. [51]
Pepsin III	Sea bream	Warm water	50	Zhou et al. [51]
Pepsin IV	Sea bream	Warm water	50	Zhou et al. [51]
Pepsin	Albacore tuna	Warm water	50	Nalinanonet al. [65]
Pepsin I	Mandarin fish	Warm water	40	Zhou et al. [60]
Pepsin II	Mandarin fish	Warm water	45	Zhou et al. [60]
Pepsin III	Mandarin fish	Warm water	40	Zhou et al. [60]
Pepsin IV	Mandarin fish	Warm water	45	Zhou et al. [60]
Pepsin I	Pectoral rattail	Warm water	45	Klomklao et al. [45]
Pepsin II	Pectoral rattail	Warm water	45	Klomklao et al. [45]

Table 2: The optimum temperature of pepsin from different fishes.