Angiotensin‐I‐Converting Enzyme Inhibitory Activities and In Vivo Antihypertensive Effects of Sardine Protein Hydrolysate

In our previous study, an antihypertensive protein hydrolysate was prepared from sardine. This study aimed to investigate the composition of sardine protein hydrolysate (SPH) and it's in vivo antihypertensive effect. SPH was separated sequentially with ultrafiltration and size exclusion chromatography. Fractions with high angiotensin‐I‐converting enzyme (ACE) inhibitory activity were further analyzed with RP‐HPLC and amino acids analysis. Then, SPH was individually oral administrated to spontaneously hypertensive rats (SHR) and normotensive wistar kyoto rats (WKY) for 4 wk. After treatment, the systolic blood pressure (SBP), organ index, oxidative status, serum ACE activity, and serum angiotensin‐II (ANG‐II) of all the rats were determined. According to the separation and analysis results, 3 main fractions with high ACE‐inhibitory activity were obtained with different amino acids composition. The animal experiments results showed that SPH could significantly reduce SBP (P < 0.05 or P < 0.01) within 4 h after a single oral administration. After a chronic oral administration, a steady state of SBP in SHR rats was attained. The heart weight index and left ventricular weight index were significantly reduced (P < 0.05) in SPH‐treated SHR rats. The malonyldialdehyde (MDA) levels in organs and serum, serum ACE activity, and serum ANG‐II concentration in SPH‐treated SHR rats were significantly lowered (P < 0.05 or P < 0.01) as compared to their controls. Meanwhile there was no significant effect (P > 0.05) on those parameters in WKY rats. These results indicate that SPH can decrease blood pressure in SHR rats and not in WKY rats.     

Phytochemical Analysis and Anti‐inflammatory Potential of Hyphaene thebaica L. Fruit

Metabolite profiling and biological activity are reported from organic and aqueous extracts of the fruit from the desert palm Hyphaene thebaica. Phenolics and oxylipids profiles were determined using UPLC‐PDA‐TOF (ultra performance‐photodiode array‐time of flight) high‐resolution mass spectrometry in order to obtain the molecular formula and exact mass Under optimized conditions, 17 compounds were simultaneously identified and quantified including 2 cinnamic acid derivatives, 5 flavonoids, 6 fatty acids, 2 sphingolipids, a lignan, and a stilbene. Sugars composition in the fruit was characterized and quantified by ¹H‐NMR (nuclear magnetic resonance) with sucrose detected as the major component in fruit at a level of 219 mg/g. Fruit organic extracts anti‐inflammatory potential was assessed in vitro by cyclooxygenase‐1 enzyme inhibition.