Parichat Hongsprabhas

Genistein as antioxidant and antibrowning agents in in vivo and in vitro: A review

Genistein is a phytoestrogen with diverse biological activities. It is a potent antioxidant and antibrowning agent in in vivo and in vitro. Genistein acts as a preventative and therapeutic effects for cancers, postmenopausal syndrome, osteoporosis and cardiovascular diseases in animals and humans. Gensitein possesses cancer related enzyme-inhibitory effect and substantially inhibits skin carcinogenesis and cutaneous aging induced by ultraviolet (UV) light in mice and photodamage in humans. Two-stage skin carcinogenesis showed genistein exhibited a moderate inhibition of ornithine decarboxylase activity through blockage of DNA adducts formation. The anticancer, anti-inflammatory, cardio-protective and enzyme-inhibitory effects of genistein might be related to their antioxidant activities. Genistein also altered the Maillard reaction pathway by trapping the advanced glycation end products (AGEs) both in biological and protein-lactose suspensions. As a result, soy isoflavone can be used to enrich or fortify different types of food products.

Physicochemical properties of starches and proteins in alkali-treated mungbean and cassava starch granules

This study explored the influences of envelope integrity of cooked starch granules on physicochemical and thermophysical properties of mungbean and cassava starches. Alkali treatment was used to selectively leach amylose from the amorphous region of both starches and partially fragmented starch molecules into lower-molecular-weight polymers. It was found that despite the loss of 40% of the original content of amylose, both mungbean and cassava starches retained similar crystallinities, gelatinization temperature ranges, and pasting profiles compared to the native starches. However, the loss of granule-bound starch synthases during alkali treatment and subsequent alkali cooking in excess water played significant roles in determining granular disintegration. The alterations in envelope integrity due to the negative charge repulsion among polymers within the envelope of swollen granules, and the fragmentation of starch molecules, were responsible for the alterations in thermophysical properties of mungbean and cassava starches cooked under alkaline conditions.

Effect of CaCl2 on the formation of Ca-induced starch aggregates and spherulitic structure in dried starch film

ABSTRACT This study investigated structure-forming process of Ca–starch aggregates and CaCO3 in alkali-treated starch suspensions and dried films. It was found that the addition of CaCl2 in starch suspensions (pH 13.4) induced the formation of Ca–starch aggregates having different flow behaviors from the suspensions in the absence of CaCl2. Drying the Ca–starch suspensions at 43°C to obtain dried starch films further induced the formation of CaCO3 spherulitic crystals (5–7 µm) homogeneously embedded in the films shown by X-ray diffractometry and scanning electron microscopy. This study revealed the use of alkali-treated starches as the template for CaCO3 crystallization during dehydration.

Physicochemical properties and flavor retention ability of alkaline calcium hydroxide-mungbean starch films

The physicochemical properties and the flavor retention ability of the dried mungbean starch film formed in the presence of calcium ions under alkaline pH were analyzed. Treating starch in a NaOH or Ca(OH)2 solution at pH 12 induced the formation B-type starch crystal. However, the starch film made with Ca(OH)2 (Ca-film) was more effective than starch film made with NaOH (Na-film) in entrapping 1,8-cineole, menthone and citonellol. Entrapment efficiency of citonellol in Ca-film which had B-type starch crystal structure was close to that of the V-type starch film formed at neutral pH using distilled water (DW-film). 1,8-cineole, menthone, and citronellol were entrapped in dried Ca-films for 5.07%, 1.52%, and 30.84%, respectively. Physical entrapment of flavor compounds by alkaline-treated starch and high water solubility (24.4-46.7 %) of Ca-films could help designing a novel controlled flavor release systems.