Dietary Phospholipids and Phytostrerols: A Review on Some Nigerian Vegetable Oils

Author(s): M. O. Aremu, Hashim Ibrahim

Dietary phospholipids and phytosterols have proven to be potential sources of bioactive lipids with widespread effects on pathways related to inflammation, cholesterol metabolism, and high-density lipoprotein function. Due to their biological and physicochemical properties, they are important in human nutrition. The efficient separation and accurate quantification of phospholipids and phytosterols can be achieved with high-performance liquid chromatography–evaporative light scattering detection (HPLC-ELSD) and gas chromatography (GC) often combined with mass spectrometry respectively. The phospholipid and phytosterol compositions of some Nigerian vegetable oils were reviewed. From the literature, the phospholipid concentrations (mg/100) of phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine, lysophosphatidyl choline, phosphatidyl inositol and phosphatidic acid are in the range of 2.60 – 1168.00, 1.13 – 558.00, 0.10 – 336.00, 0.72 – 596.00, 1.01 – 611.00 and 9.24 – 94.06, respectively. Total phospholipids range from 14.30 mg/100g in Ethiopian pepper to 2040.00 mg/100g in cooked groundnut. The values of cholesterol, choslestanol, ergosterol, campesterol, stigmesterol, 5 – avenasterol and sitosterol range between 1.6e-5 – 9.28, 4.80e-6 – 2.28, 4.59e-4 – 30.20, 9.39e-3 – 103.00, 1.24 – 45.60, 5.62e-3 – 53.50 and 17.21 – 351.00, respectively for the vegetable oils under review. Malaba spinach records the highest total phytosterols content (442.91 mg/100g), followed by big alligator pepper (369. 34 mg/100g) while Ethiopian pepper contains the least total phytosterols of 23.82 mg/100g. The results of this reviewed work indicate that Nigerian vegetable oils have potentials in finding application either in food industry as emulsifiers, emulsion stabilizers or industrial purposes such as biomedical applications, cosmetics and even drug delivery.

Phosphlipids, Phytosterols, Vegetables, Oils, Nigeria

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