br Soybeans types of soy food products
Soybeans, types of soy food products and their nutritional functions and consumption
Soybean isoflavones: genistein, daidzein, glycitein, and formononetin
The association of soy isoflavone food consumption with incidence and prognosis of breast cancer
Possible molecular mechanisms of chemopreventive effects of genistein on breast cancer Soy isoflavones are structurally similar to endogenous estrogens (Fig. 4) and may affect breast cancer through both hormonally mediated and non-hormonally related mechanisms. Among soy isoflavones, genistein (GEN) is believed to be a potent chemopreventive agent for breast cancer and thus, more studies have been focused on its chemopreventive effects on breast cancer cells. Recent studies have suggested that GEN can enhance the anticancer capacity of an estrogen antagonist, TAM, especially in ERα-positive breast cancer cells. The chemopreventive effects of GEN could be mediated via the several pathways and mechanisms.
Summary and prospective
Definition of dietary fiber The definition of dietary fiber (DF) proposed by American Association of Cereal Chemists (AACC) defines DF being made up of edible part of plants or analogous carbohydrates that are resistant to digestion and hedgehog pathway in the human small intestine as well as having beneficial physiological effects such as laxation, blood glucose attenuation and/or blood cholesterol attenuation . More specifically, dietary fiber means carbohydrate polymers with ten or more monomeric units, which are not hydrolyzed by the endogenous enzymes in humans . These non-digestible carbohydrate (NDC) polymers should occur naturally in the food as consumed and have been obtained from food raw material by physical, enzymatic or chemical means and which have been shown to have a physiological effect of benefit to health as demonstrated by generally accepted scientific evidence to competent authorities .
Demand for DF and its products The increasing public awareness of DF\'s potential health benefits has greatly encouraged food manufacturers to develop a wide range of fiber-enriched or fiber-fortified food products [3,4]. Nowadays, most DF ingredients (such as cereals-based, fruits-based, and legumes-based DF) are originated from the by-products of their corresponding food processing (e.g. milling, juice extraction, de-hulling, etc.) followed by different refining steps (such as grinding, sieving, bleaching, defatting, etc.) in order to meet a wide range of customers’ requirements [5–7]. Because of the highly competitive market of fiber-enriched food products, exploration of alternative source of DF as well as DF preparation method is urgent needed .
DF and human health It has been demonstrated by extensive research in the past three decades that sufficient DF intake has benefits for health maintenance and disease prevention including cardiovascular disease, diabetes, cancer and weight regulation [9–13]. Therefore, DF research has drawn much attention recently, particularly in the growing nutraceutical industry [14,15]. DF of different origins has different structures, chemical composition, and physico-chemical properties that would exhibit different nutritional, technological and physiological benefits [16,17].
Mushrooms as source of DF Compared to other conventional sources of DF, such as cereals, fruits, legumes and vegetables, mushrooms or fungi are underutilized [7,8]. In fact, edible mushrooms or macrofungi are a rich source of some novel DFs that have various beneficial health effects to humans which are discussed below. Mushrooms are defined as fungi that have distinctive and visible fruiting bodies  and they include edible and medicinal ones. The fruiting bodies of edible mushrooms (e.g. Lentinus edodes) are mainly consumed in their flesh or dried form, while medicinal mushrooms (e.g. Ganoderma lucidum) are non-edible fungi that have biopharmaceutical applications due to the bioactive components such as polysaccharides and triterpenoids that they contain.