TABLE 4.

Bioactive peptides derived from oyster whole tissue.

Biological activity	Species	Enzyme used	Oyster peptides and/or MW	Results	References
Antihypertensive activity	Crassostrea talienwhanensis	Pepsin	VVYPWTQRF (1195 Da)	ACE inhibitory activity and decrease the systolic blood pressure (SBP)	Wang et al. (2008)
	Crosse
	Crassostrea gigas (FOS)		(592.9 Da)	ACE-inhibitory activity and decrease the SBP by 12 mmHg after 3 h	Je et al. (2005)
	Crassostrea gigas	Trypsin	DLTDY	ACE inhibitory activity and decrease the SBP	Shiozaki et al. (2010)
	Pinctada fucata		HLHT and GWA	ACE inhibitory activity and efficient antihypertensive effect on SRH rats	Liu et al. (2019)
	Crassostrea angulata	Pepsin, bromelain, and papain		Higher ACE and DPP-IV activity observed in pepsin hydrolysates	Gomez et al. (2019)
Anti-inflammatory activity	Crassostrea gigas	Protamex	QCQCAVEGGL	Inhibit NO production in RAW264.7 cells and Decrease and increase the serum IgE and spleen CD4+/CD8+ levels in Male BALB/c mice, respectively	Hwang et al. (2012)
		Microbial transglutaminase, protamex and neutrase	YA	Inhibit NO production in RAW264.7 cells	Xie et al. (2018)
	Crassostrea gigas	Trypsin	β-thymosin (4656.4 Da)	Inhibits NO production in LPS-induced RAW264.7 cells and PGE2, iNOS and COX-2 expression; Inhibits the inflammatorycytokines (TNF-α, IL-1β, IL-6), repress the nucleartranslocationof phosphorylated nuclear factor-κB and degradation of inhibitor of nuclear factor-κB	Hwang et al. (2019)
	Crassostrea talienwhanensis	Pepsin		Repress inflammatory cytokines and mediators (TNF-α, IL-1β, IL-6, iNOS) at transcription level in LPS-induced RAW264.7 cells	Qian et al. (2020)
Anticoagulant activity	Crassostrea gigas	Pepsin, trypsin papain and nuetral protease	DFEEIPEEYLQ and TARNEANVNIY (1264.36)	Thrombin inhibition including prolonged the activated partial thromboplastin	Cheng et al. (2018)
	Crassostrea gigas	Pepsin and pancreatin	LSKEEIEEAKEV	Prolong the APTT and TT, inhibit thrombin	Chen et al. (2018)
	Crassostrea gigas	Pepsin	P-3-CG	Prolong the APTT and decrease the mortality in male Kumming mice	Cheng et al. (2021)
Anticancer activity	Crassostrea gigas	Protease	Oligopeptide-enriched hydrolysates (<3 kDa)	Inhibition against the growth of sarcoma-s-180 in BALB/c mice	Wang et al. (2010)
	Crassostrea gigas	Flavourzyme	HFNIGNRCLC	Cytotoxicity including apoptosis of prostate, breast, and lung cancer cells but not normal liver cells	Cheong et al. (2013)
	Saccostrea cucullata	Protease isolated from Bacillus cereus SU12	LANAK	Activity against the HT-29 cell lines	Umayaparvathi et al. (2014)
Anti-fatigue	Ostrea plicatula	Nutrease		prolonged swimming time and incresed glycogen in liver and gastrocnemius muscle; decrease the serum lactic acid and BUN male Kumming mice	Hao et al. (2013)
	Gmelin
	Ostrea rivulari	Compound protease	(<6 kDa)	Increase in exercise tolerance, liver glycogen and muscle glycogen, decrease the levels of BUN in male Kumming mice	Miao et al. (2018)
		Nutrease		Prolong the swimming time, increase the levels of liver glycogen,	Xiao et al. (2020)
				decrease the levels of lactic acid
Anti-wrinkle	Crassostrea gigas	Protamex, Neutrase and AMG		Anti-melanogenic activities via downregulation of cAMP signaling in B16F10 cells and decreased the number of active melanocytes and melanin granule in UVB-irradiated mice group	Han et al., 2019
Reproduction enhancing
		Neutrase, papain, bromelain	(343 Da)	Rats with reproductive dysfunction induced by cyclophosphamide exhibited Increase the level of key regulatory protein expression and androgen in the blood	Li et al. (2020)
	Crassostrea gigas	SPE	Cg-GnRH-a (pQNYHFSNGWQPa) and CgGnRH-G (pQNYHFSNGWQPG)	Regulate the neurological and endocrine factors and supports the nutrition and energy demand during reproduction	Bigot et al. (2012)
	Crassostrea iredalei			Ethanol extract showed the aphrodisiac property	Ridzwan et al. (2013)
Osteogenic	Crassostrea gigas	Pepsin, pancreatin	YRGDVVPK (992.40 Da)	Promote the proliferation of MC3T3-E1 cells	Chen et al. (2019)
	Crassostrea gigas (fermented oyster extract)			Osteoclastogenesis by inactivating the NF-κB-mediated NFATc1 and c-Fos signaling pathways and scavenging the ROS generation in RAW 264.7 Cells
Zinc-binding	Crassostrea gigas	Pepsin		Peptide-zinc complex promoted the intestinal absorption of zinc via the zinc ion channel and the small peptide transport pathway	Li et al. (2019)