Validation and theoretical justification of an LC-MS method for the animal species specific detection of gelatin.

Collagen is the most abundant protein family in mammals. Commercial edible gelatins are often produced from bovine and porcine skin and bone and consist mainly of partially hydrolyzed collagen type 1. The gelatin industry would benefit from a sensitive and reliable species detection method to unambiguously demonstrate species authenticity of their products.

Angiotensin I-converting enzyme inhibitory activity of gelatin hydrolysates and identification of bioactive peptides.

In this project we report on the angiotensin I-converting enzyme (ACE)-inhibitory activity of a bovine gelatin hydrolysate (Bh2) that was submitted to further hydrolysis by different enzymes. The thermolysin hydrolysate (Bh2t) showed the highest in vitro ACE inhibitory activity, and interestingly a marked in vivo blood pressure-lowering effect was demonstrated in spontaneously hypertensive rats (SHR). In contrast, Bh2 showed no effect in SHR, confirming the need for the extra thermolysin hydrolysis.

Antihypertensive effect of insect cells: in vitro and in vivo evaluation.

In this study, we investigated the in vitro ACE inhibitory and in vivo antihypertensive effect of insect cell extracts. The IC(50) of three insect cell lines from different type and insect species origin: S2 (embryo, Drosophila melanogaster), Sf21 (ovary, Spodoptera frugiperda) and Bm5 (ovary, Bombyx mori), were evaluated. Most interesting results were that the IC(50) values ranged between 0.

Ala-Val-Phe and Val-Phe: ACE inhibitory peptides derived from insect protein with antihypertensive activity in spontaneously hypertensive rats.

In this study, we evaluated the stability/bioavailability and in vivo antihypertensive activity of the tripeptide, Ala-Val-Phe, that was recently purified from insect protein (Spodoptera littoralis; Lepidoptera) and that showed in vitro angiotensin converting enzyme (ACE) inhibitory activity. This tripeptide is partly hydrolyzed by mucosal peptidases to Val-Phe, a more potent in vitro ACE inhibitor. In organ bath experiments using rat aorta, Val-Phe showed ACE inhibition, while Ala-Val-Phe did not.

ACE inhibitory activity in enzymatic hydrolysates of insect protein.

In this paper, ACE inhibitory activity in insect protein hydrolyzed by various enzymes (gastrointestinal proteases, alcalase, and thermolysin) is reported for the first time. Four insects of different insect orders were tested: Spodoptera littoralis (Lepidoptera), Bombyx mori (Lepidoptera), Schistocerca gregaria (Orthoptera), and Bombus terrestris (Hymenoptera). ACE inhibitory activity was measured by two different methods: a spectrophotometric method using FAPGG (2-furanacryloyl-phenylalanyl-glycyl-glycine) as substrate, and an HPLC method using dansyltriglycine (DTG) as substrate.