Germinated brown rice (GBR) consists of bioactive compounds (BCs) that are very useful for diabetes treatment. Modified GBR-based flour (MGBRF) was produced by modifying the starch in GBR with 0, 299.19, 598.38, and 897.57 U/ml of cyclodextrin glycosyltransferase (CGTase) for 1 hr and then spray-dried to examine its antidiabetic and cytotoxic effects. The results showed that the slowly digestible starch and resistant starch by modifying the starch in GBR with 598.38 U/ml of CGTase were 55.8% and 5.92% corresponding to the increase of γ-amino butyric acid (GABA) and ferulic acid (FA) with 4.31 ± 0.68 mg/ml and 3.10 ± 0.02 mg/ml, respectively. The extract from MGBRF showed strong cytotoxic capacity against HepG2. Furthermore, the in vivo study revealed the stability of the glycemic index (GI) by consuming MGBRF with significant impacts on diabetes. These results suggest that MGBRF through the action of CGTase plays a major role in antidiabetes and HepG2 cell product value addition. Practical applications GBR consists of BCs that are useful for diabetes and cancer treatment. However, when using this or GBR-based products, it is difficult to evaluate the effect of functional properties, especially for diabetes and/or cancer diseases due to high starch content. Therefore, the modification of starch to limit digestible starch, increase SDS and RS as well as to enhance the effect of BCs on diabetes and cytotoxic activity on cancer cell should be studied before producing various based products from GBR. The results in this study indicated that CGTase increased BCs without any glycosides BCs in the extract. The MGBRF changed to higher RS and SDS while increasing the BCs. The extract of MGBRF showed strong cytotoxic activity against HepG2 cell and a positive effect on type 2-diabetic mice. Hence, this study produces new information for effective use of GBR-based food as a functional food.

Roasting temperature and time are important parameters in the process of roasted germinated brown rice flour (RGBRF), which cause the loss of bioactive ingredients and sensory value of the product. During roasting and storage, fat oxidation is also one of the problems that reduce the quality of RGBRF. In order to complete the RGBRF process, experiments using different temperature and time as 160oC, 200oC, 240oC for 10 to 30 mins were done to find the best roasting conditions. To limit the oxidation of fat during the processing and preserving RGBRF, ergothioneine (ERG) extract from enoki mushroom were supplemented at 3%, 5%, 7% and 10% (w/w) before roasted, the product was then ground and put into two types of packaging (PA and aluminum), vacuum seamed and stored at room temperature for 8 weeks were carried out. The results showed that germinated brown rice (GBR) which supplemented 3% of the extract before roasted at 200oC for 30 mins showed the best quality in term of sensory value, γ-aminobutyric acid (GABA) content and helped to limit fat oxidation as well as maintained stable quality after 8 weeks of storage in PA and aluminum packaging. In addition, the results from in vitro of starch resistance and in vivo of sugar absorption capacity in rats showed that RGBRF did not significantly change the GI index as well as the ability to absorb sugar compared to unroasted product. The results indicated that RGBRF should be used as a nutritious food with the ability to supplement bioactive compounds to the people at risk of lifestyle diseases.

To develop a value-added product from germinated brown rice (GBR), an experiment was developed to optimise the production conditions for a sweet beverage enriched with bioactive compounds (EBCSB) by optimising the A. oryzae spore ratio (0.3 - 0.6%), ratio of GBR to A. oryzae (GA), steamed GBR (SG) (1:3 to 1:9), and hydrolysis process. Results showed that GBR after cooking with water (GBR: water at 1:1.5), and when used as a medium for spore inoculation (0.4%) at 40°C for 36 h yielded the highest amylase activity in GA (2.37 UI/g). Subsequently, GA and SG at 1:5 ratio was incubated at 60°C for 6 h, and yielded the best composition of glucose, gamma-amino butyric acid, and ergothioneine at 12.18%, 883.9 mg/kg, and 210.9 mg/kg, respectively. The product was then sterilised at 121°C for 4 min corresponding to Fvalue = 7.47 (Fo = 7) to increase product safety and maintain good quality for eight weeks. Results further indicated that GBR can be used to produce EBCSB that is good for health.