Fenugreek seed (Trigonella foenum graecum) protein hydrolysate loaded in nanosized liposomes: Characteristic, storage stability, controlled release and retention of antioxidant activity

This study aimed to produce fenugreek protein hydrolysates by alcalase, pancreatin, pepsin and trypsin at hydrolysis time of 30–180 min and loading the hydrolysates in nanoliposomes to improve the bioavailability. Instability and untargeted delivery of fenugreek protein hydrolysates limit the use of their health beneficial properties. Loading protein hydrolysates in nanoliposomes can reduce these limitations and the addition of cholesterol to liposome formulation, in some cases, can help the vesicle assembling. Fenugreek protein hydrolysates produced by alcalase and pancreatin showed the highest antioxidant potential, so they have been and loaded into nanoliposomes containing 0.01–0.03% cholesterol. The physicochemical properties, antioxidant activity, stability, release rate, encapsulation efficiency and morphology of nanoliposomes were evaluated. Nanoliposomes were spherical particles with smooth surfaces and the average size of 16.53–25.75 (nm). The addition of cholesterol to liposomes address an increase of encapsulation efficiency of protein hydrolysates and stability of vesicles. When 0.03% of cholesterol was used the best features were obtained. FTIR spectroscopy indicated that fenugreek protein hydrolysates located inside the polar parts of vesicles and formed hydrogen bonds with phosphatidylcholine. In conclusion, nanoliposomes containing 0.03% cholesterol are efficient for protecting the bioactivity of fenugreek protein hydrolysates and their control release.