Soy germs have an oil content of 6 – 8% only. The oil is therefore best extracted with supercritical carbon dioxide.
It contains more than 70% polyunsaturated omega-6 and omega-3 fatty acids as well as unusually high content of tocopherols and phytosterols. The special feature is the out-standing high phytosterol content of 5 - 8% which is found in the genuine CO2-extract without further refinement. In contrast hexane extracted and pressed soy germ oils have much lower sterol content.
Phytosterols are pentacyclic triterpenes. These secondary plant ingredients encourage cell division and are important cell membrane components with protective and anti-aging efficacy.
Phytosterols stimulate keratinocyte proliferation and hyaluronic acid synthesis; they have repair property and improve skin elasticity and smoothness. As a result the epidermis is thickened and regenerated which means improved barrier function, reduced transepidermal waterloss and less wrinkles.
The effect applies as well for internal application. As dietary supplement the extract has in addition LDL-cholesterol lowering efficacy by competitive inhibition of cholesterol absorption. Phytosterols display positive efficacy also in case of early benign prostate hyperplasia, and prophylactic efficacy is reported against bowel cancer.
In cosmetic application soy germ extract is recommended for lip plumper and balm, for anti-aging and moisturizing as well as for skin firming and anti-wrinkle products.
K.-W. Quirin