(448–755 g kg
À1 ), campesterol (32–197 g kg
À1 ), stigmasterol (41–128 g kg
À1 ) and
7-stigmastenol (8–274 g kg
À1 ). During absorption in the intestine owing to its
similarity in structure with cholesterol, it competes with cholesterol and, thus,
reduces the blood cholesterol levels (Lagarda et al. 2006). Research has demonstrated that even low levels of phytosterols (about 2 g per day) are helpful in
lowering serum LDL-cholesterol absorption. Such low quantities of phytosterols
can easily be obtained through diet loaded with plant foods (Racette 2017). Besides,
they also offer protection against colon, breast and prostate cancer and improve
immunity (Awad and Fink 2000). Sunflower oil has been reported to contain
approximately 0.22% triterpenes (Fedeli et al. 1966). A comprehensive review
published on the health effects of triterpenes suggested that triterpenes confers
anti-microbial, anti-protozoal, anti-arthritic, anti-diabetic, anti-cancerous, antiinflammatory and immunomodulatory effects (Siddique and Saleem 2011).
5.6.3 Phospholipids
Phospholipids, the essential components of the seed oil body, act as emulsifiers and
stabilizers and, thus, improve the texture of multiphase food materials (Pasini et al.
2013). Furthermore, they can also act as antioxidants owing to their synergistic
action in decomposing hydroperoxides and their metal scavenging activity (Koga
and Terao 1994; Carelli et al. 1997). Sunflower seed is a good source of phospholipids, primarily phosphatidylcholine (38.5–230 mg/100 g) and phosphatidylethanolamine (61.5–123 mg/100 g), along with minor amounts of phosphatidylinositol
and phosphatidic acid with a total concentration lower than 1.2% (Padley et al. 1994;
CSA 1999; Duke and Beckstrom 1999). Lecithin, the major phospholipid, is
hydrolysed in the intestine by phospholipase C to yield choline, a membrane
phospholipid which provides choline reserve for neurotransmitter (acetylcholine)
synthesis and is also important for normal liver function (Mihai and Steven 2013).
5.6.4 Phytoestrogens
Phytoestrogens fall mainly under two categories: isoflavones (e.g. genistein and
daidzein) and lignans (e.g. secoisolariciresinol, matairesinol). Sunflower seeds have
relatively low content of isoflavones. Kuhnle et al. (2008) observed phytoestrogens,
isoflavones and lignans in sunflower oilseeds to the value of 111.0, 2.0 and 9.0 μg/
100 g (wet basis), respectively. However, Tham et al. (1998) reported a very high
amount of lignans (400 μg/100 g) in sunflower seeds. Phytoestrogens may have
favourable estrogenic effects on the risk of cardiovascular disease, hypercholesterolemia, carcinogenic activity, osteoporosis and hormone-regulatory effects (Tham
et al. 1998).
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À1 ), campesterol (32–197 g kg
À1 ), stigmasterol (41–128 g kg
À1 ) and
7-stigmastenol (8–274 g kg
À1 ). During absorption in the intestine owing to its
similarity in structure with cholesterol, it competes with cholesterol and, thus,
reduces the blood cholesterol levels (Lagarda et al. 2006). Research has demonstrated that even low levels of phytosterols (about 2 g per day) are helpful in
lowering serum LDL-cholesterol absorption. Such low quantities of phytosterols
can easily be obtained through diet loaded with plant foods (Racette 2017). Besides,
they also offer protection against colon, breast and prostate cancer and improve
immunity (Awad and Fink 2000). Sunflower oil has been reported to contain
approximately 0.22% triterpenes (Fedeli et al. 1966). A comprehensive review
published on the health effects of triterpenes suggested that triterpenes confers
anti-microbial, anti-protozoal, anti-arthritic, anti-diabetic, anti-cancerous, antiinflammatory and immunomodulatory effects (Siddique and Saleem 2011).
5.6.3 Phospholipids
Phospholipids, the essential components of the seed oil body, act as emulsifiers and
stabilizers and, thus, improve the texture of multiphase food materials (Pasini et al.
2013). Furthermore, they can also act as antioxidants owing to their synergistic
action in decomposing hydroperoxides and their metal scavenging activity (Koga
and Terao 1994; Carelli et al. 1997). Sunflower seed is a good source of phospholipids, primarily phosphatidylcholine (38.5–230 mg/100 g) and phosphatidylethanolamine (61.5–123 mg/100 g), along with minor amounts of phosphatidylinositol
and phosphatidic acid with a total concentration lower than 1.2% (Padley et al. 1994;
CSA 1999; Duke and Beckstrom 1999). Lecithin, the major phospholipid, is
hydrolysed in the intestine by phospholipase C to yield choline, a membrane
phospholipid which provides choline reserve for neurotransmitter (acetylcholine)
synthesis and is also important for normal liver function (Mihai and Steven 2013).
5.6.4 Phytoestrogens
Phytoestrogens fall mainly under two categories: isoflavones (e.g. genistein and
daidzein) and lignans (e.g. secoisolariciresinol, matairesinol). Sunflower seeds have
relatively low content of isoflavones. Kuhnle et al. (2008) observed phytoestrogens,
isoflavones and lignans in sunflower oilseeds to the value of 111.0, 2.0 and 9.0 μg/
100 g (wet basis), respectively. However, Tham et al. (1998) reported a very high
amount of lignans (400 μg/100 g) in sunflower seeds. Phytoestrogens may have
favourable estrogenic effects on the risk of cardiovascular disease, hypercholesterolemia, carcinogenic activity, osteoporosis and hormone-regulatory effects (Tham
et al. 1998).
134
S. Khurana and R. Singh