BLBS102-c36 BLBS102-Simpson March 21, 2012 18:47 Trim: 276mm X 219mm Printer Name: Yet to Come
688 Part 6: Health/Functional Foods
Table 36.1.Angiotensin Converting Enzyme (ACE) Inhibitory Peptides Derived from Fishery Sources
Source Enzyme Peptide Sequence IC 50 Va l u ea References
Tuna frame Peptic enzymes Gly–Asp–Leu–Gly–Lys–Thr–Thr–
Thr–Val–Ser–Asn–Trp–Ser–Pro–
Pro–Lys–Try–Lys–Asp–Thr–Pro
11.28μM Lee et al. (2010)
Shark meat Protease Cys–Phe 1.96μM Wu et al. (2008)
Glu–Tyr 2.68μM
Phe-Glu 1.45μM
Bigeye tuna dark
muscle
Pepsin Trp–Pro–Glu–Ala–Ala–Glu–Leu–
Met–Met–Glu–Val–Asp–Pro
21.6μM Qian et al. (2007)
Anchovy natural fermentation Arg–Pro 21 μM Ichimura et al. (2003)
Lys–Pro 22 μM
Ala–Pro 29 μM
Salmon Thermolysin Val–Trp 2.5μM Ono et al. (2003)
Ile–Trp 4.7μM
Met–Trp 9.9μM
Leu–Trp 17.4μM
Cuttlefish Bacterial protease Ala–His–Ser–Tyr 11.6μM Balti et al. (2010a)
Gly–Asp–Ala–Pro 22.5μM
Ala–Gly–Ser–Pro 37.2μM
Asp–Phe–Gly 44.7μM
Cuttlefish Proteases Val–Tyr–Ala–Pro 6.1μM Balti et al. (2010b)
Val–Ile–Ile–Phe 8.7μM
Met–Ala–Trp 16.32μM
Shrimp Peptide enzymes Leu–His–Pro 1.6μM Cao et al. (2010)
Shrimp Lactobacillus fermentum
enzymes
Asp–Pro 2.15μM Wang et al. (2008b)
Gly–Thr–Gly 5.54μM
Ser–Thr 4.03μM
Hard clam Protamex Tyr–Asn 51 μM Tsai et al. (2008)
Oyster Pepsin Val–Val–Tyr–Pro–Trp–Thr–Gln–
Arg–Phe
66 μM Wang et al. (2008a)
Freshwater clam Protamex and
flavourzyme
Val–Lys–Pro 3.7μM Tsai et al. (2006)
Val–Lys–Lys 1045 μM
Blue mussel Natural fermentation Glu–Val–Met–Ala–Gly–Asn–Leu–
Tyr–Pro–Gly
19.34μg/mL Je et al. (2005d)
aIC 50 value is defined as the concentration of inhibitor required to inhibit 50% of the ACE activity.
pressure by 11 mm Hg, while the control group showed no
decrease. Lee et al. (2010) reported that a single oral administra-
tion (10 mg/kg of body weight) of peptide from tuna frame hy-
drolysate displayed a strong suppressive effect on systolic blood
pressure of SHR and this antihypertensive activity was similar to
captopril. Moreover, no adverse side effects were observed in the
rats after administration of antihypertensive peptide. Although,
the exact mechanisms underlying this phenomenon have not yet
been identified, it was suggested that bioactive peptides have
higher tissue affinity and are subjected to a slower elimination
than captopril.
Currently, protein hydrolysates from the bonito and sardine
are widely available as supplements in Japan (Guerard et al. ́
2010). Bonito hydrolysate is also being sold in North Amer-
ica as a supplement to lower blood pressure. Similar products
have been derived from other proteins, including soy and whey.
However, active dosages in these nonmarine products are 1020
g/day, whereas bonito protein hydrolysis, for example, has a
recommended daily dosage of only 1.5 g/day. A low daily dose
is important for both ingredient cost and ease of formulation.
Marine-derived bioactive peptides have potential for use as func-
tional ingredients in nutraceuticals and pharmaceuticals due to
their effectiveness in both prevention and treatment of hyperten-
sion. However, further studies are needed with clinical trials for
these antihypertensive peptides.
Antioxidant Activity
Lipid oxidation is one of the major deteriorations in many types
of natural and processed foods, leading to changes in food
quality and nutritional value and also production of potentially
toxic reaction products. Furthermore, lipid oxidations are major