Hypertension is an important factor in cardiovascular diseases. Angiotensin-I-converting enzyme (ACE) inhibitors like synthetic drugs are widely used to control hypertension. ACE-inhibitory peptides from food origins could be a good alternative to synthetic drugs. A number of plant-based peptides have been investigated for their potential ACE inhibitor activities by using in vitro and in vivo assays. These plant-based peptides can be obtained by solvent extraction, enzymatic hydrolysis with or without novel food processing methods, and fermentation. ACE-inhibitory activities of peptides can be affected by their structural characteristics such as chain length, composition and sequence. ACE-inhibitory peptides should have gastrointestinal stability and reach the cardiovascular system to show their bioactivity. This paper reviews the current literature on plant-derived ACE-inhibitory peptides including their sources, production and structure, as well as their activity by in vitro and in vivo studies and their bioavailability.

Apium plants belong to the Apiaceae family and are included among plants that have been in use in traditional medicine for thousands of years worldwide, including in the Mediterranean, as well as the tropical and subtropical regions of Asia and Africa. Some highlighted medical benefits include prevention of coronary and vascular diseases. Their phytochemical constituents consist of bergapten, flavonoids, glycosides, furanocoumarins, furocoumarin, limonene, psoralen, xanthotoxin, and selinene. Some of their pharmacological properties include anticancer, antioxidant, antimicrobial, antifungal, nematocidal, anti-rheumatism, antiasthma, anti-bronchitis, hepatoprotective, appetizer, anticonvulsant, antispasmodic, breast milk inducer, anti-jaundice, antihypertensive, anti-dysmenorrhea, prevention of cardiovascular diseases, and spermatogenesis induction. The present review summarizes data on ecology, botany, cultivation, habitat, medicinal use, phytochemical composition, preclinical and clinical pharmacological efficacy of Apium plants and provides future direction on how to take full advantage of Apium plants for the optimal benefit to mankind.

Spirulina platensis is one of the most significant multicellular blue-green Cyanobacterium microalgae with a high protein content. The complex coacervation as an encapsulation technique allows the formation of proteins with improved functional properties and thermal stability. In this study, the effects of pH and Spirulina platensis protein concentrate (SPPC)—chitosan ratio on complex coacervation formation were examined in terms of ζ-potential, turbidity, visual observation and microscopic images. Based on the results, the strongest interaction between SPPC and chitosan occurred at pH of 5.5 and SPPC—chitosan ratio of 7.5:1 with a precipitation in the test tubes. Stable dispersions were obtained at a pH range of 2–4 for the SPPC—chitosan ratio of 7.5:1 inhibiting the precipitation which occurs at individual SPPC solutions at this pH range. Characteristic organic groups in the individual SPPC and chitosan solutions as well as the SPPC—chitosan coacervate formed at the optimal conditions were identified by using Fourier Transform Infrared (FT-IR) spectroscopy technique. Furthermore, thermal stability of the individual SPPC and chitosan solutions and the SPPC—chitosan coacervates were investigated using differential scanning calorimetry (DSC). The glass transition temperature and enthalpy were 209.5 °C and − 3.414 W/g for the complex coacervates and 180.5 °C and − 0.877 W/g for SPPC. It means that complex coacervation provided more thermally-stable SPPC in chitosan—SPPC coacervate than that of the individual SPPC. Our results might have important implications for the utilization of Spirulina platensis proteins especially for acidic beverage applications.