Anti-Oxidation Activity of Various Rice Brans

Abstract

The original concept of rice brands resulted from consumer demand for a quality improvement in rice. In the Edo era, when rice was identified with the locality of its production, rice types such as Sanuki-mai and Omi-mai were given the brand name of their region. Rice brands and the areas of their distribution were thus named according to the brands of the prefecture. In 1970 the current naming system and distribution system were established to ensure a smooth distribution of rice. Since 1979 the government has regulated the purchase prices according to growing locality, variety and brand. The range between these prices has been increased in order to encourage the production of higher quality rice.It is assumed that plants that grow in strong sunlight under conditions of oxygen stress, contain a highly active anti-oxidants. (1) These anti-oxidants metabolize active oxygen and radicals in plants, they have a role in preventing aging and various diseases such as cancer, and they a noticeable beneficial influence on health. (2-4) The degree to which the DPPH radical (1, 1-Diphenyl-2-picrylhydrazyl, a free radical) is scavenged by such compounds can be used to determine anti-oxidation efficacy. The authors therefore studied the radical-scavenging effects of, and the anti-oxidants contained in, bran obtained at different milling yields of rice of ten brands and varieties. Firstly, the DPPH radical-scavenging effects were compared between brown and milled Nihonbare rice (90% milling yield) of different harvest years. A higher DPPH radical-scavenging activity was confirmed for brown rice. These results, lead to the study of the radical-scavenging activity of nine cultivars of high quality rice and then the differences in those activities were identified. The DPPH radical-scavenging effects of bran obtained at seven steps of milling yields of Nihonbare rice from different harvest years (1996 to 2002) were also investigated. The results identified which step (milling yield) produced bran with the highest anti-oxidation efficacy and which compound was associated with it. Abstract: It is well known that most of the nutritional components of rice are contained in outer layers of bran and germ and that these have various effects on the health of the consumer. This study aimed to clarify the anti-oxidation activity of the bran of rice of ten cultivars, including the standard cv. Nihonbare. Rice samples were milled through seven discrete steps of milling yield, i.e. 98-100%, 96-98%, 94-96%, 92-94%, 90-92%, 88-90% and 88-100%. The radical-scavenging activity, including that against the active oxygen, was investigated on the bran obtained from each step. The results showed that bran obtained from a milling yield of 98-100% of newly harvested rice has the highest anti-oxidation effect. 585 JOS

Evaluation of γ-oryzanol content and composition from the grains of pigmented rice-germplasms by LC-DAD-ESI/MS

“…In the present study, a total of 10 components were isolated of which, cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, campesteryl ferulate and sitosteryl ferulate were identified as the major components. Interestingly, herein analysis time was shortened to 40Âminutes compared with previous report of 60Âminutes and the peak retention time ranged between 15–30Âminutes [38,40,41]. …”

Suppressive effect of defatted rice bran on the oxidation of methyl linoleate

“…That is, the induction period for the oxidation of ML with DRB from 96-98% and 98-100% yield was prolonged. It has been reported that the rice bran of 98-100% milling yield, which is not defatted, exhibits the highest radicalscavenging activity in the bran samples of Nihonbare rice from the different milling yields (88-100%) and a-tocopherol and coryzanol are the main antioxidants in the bran (Fujita et al, 2006). Similarly to these lipophilic antioxidants, hydrophilic compounds having antioxidative activity, such as various phenolic compounds, in the branny layer, would be in outer branny layers to defend the endosperm against the external oxidative stress (Asada, 1999).…”

“…Rice bran is a major by-product obtained from the milling process. Lipids extracted from rice bran include antioxidative compounds, such as tocopherols and c-oryzanol (Fujita, Masumoto, Kawakami, Mikami, & Nomura, 2006), and they have been used as food material with a beneficial influence on health. On the other hand, defatted rice bran (DRB) with these lipophilic components removed is not used enough, despite its potential availability.…”

Hypotensive Effect of Rice Bran Discarded after Heshiko Processing

“…Fresh rice bran has been shown to contain various nutritional compounds, including vitamins and oils (Iwai and Yokomizo, 1967;Shimizu et al, 1957;Kato et al, 1981), as well as exhibiting various physiological functions (NaraiKanayama et al, 2007;Saito et al, 1992;Kaneda et al, 2006;Fujita et al, 2006;Hiwatari et al, 2010;Arimura et al, 2003;Inokuchi et al, 2003;Aoe et al, 1989;Ayano et al, 1980;Naito et al, 2003), such as angiotensin I-converting enzyme (ACE) inhibitory activity (Narai-Kanayama et al, 2007;Saito et al, 1992), and antioxidative effects (Kaneda et al, 2006;Fujita et al, 2006). Fresh rice bran contains about 13% crude protein (w/w) on a wet basis (Ministry of Education, Culture, Sports, Science and Technology, 1982).…”