Study on quality standard of rice as excipients during rice stir-frying method / 中国中药杂志

Commercially available japonica rice and indica rice with different trade names were collected,and then based on the method of rice stir-frying,their many indexes were evaluated,for example the physical and chemical properties such as appearance color,grain type,broken kernel ratio,length-width ratio,1 000-grain weight,specific heat capacity,moisture content,amylose content,and protein content. The discriminant function analysis was used to determine the effective factors affecting the quality of rice as excipients. The results showed that two types of rice could be distinguished by rice color parameter a*,grain parameter circularity,1 000-grain weight and amylose content. These four effective factors can be used as the quality evaluation indexes for fried rice as excipients.Protein is one of the main components of rice,and its content affects the quality of rice. There is a significant difference in the protein content between japonica rice and indica rice. Therefore,protein content should be used as one of the evaluation indexes for rice quality. After comprehensive consideration,it is suggested that the red-green value a*shall not be less than 0. 50; the circularity not less than 53. 0,the 1 000-grain weight not less than 16. 0 g,the amylose content not less than 12. 0% and the protein content not less than4. 0% in the japonica rice; the red-green value a*shall not be lower than-1. 0,the circularity not less than 41. 0,the 1 000-grain weight not less than 13. 0 g,the amylose content not less than 9. 0% and the protein content not less than 3. 5% in the indica rice. In this study,the quality evaluation standards for rice as excipients( japonica rice,indica rice) were supplemented and improved,laying foundation for the development of quality standards for rice as excipients with the rice stir-frying method.

Effect of rice varieties on quality of rice-washed water / 中草药

Objective: To study the effect of rice varieties on the quality for preparation of rice-washed water. Methods: The starch contents of rice-washed water were determined by acid hydrolysis-Fehling’s solution titration with the content of starch and rice-washed water characters as indicators. The characters of rice-washed water were determined by ultraviolet visible spectrophotometric method and the adsorption was verified to explore the effect of particle size of japonica rice, indica rice, round glutinous rice, and long glutinous rice on the quality of rice-washed water. Results: The comprehensive evaluation showed that the starch content and the characters of rice-washed water prepared by long glutinous rice fine powder were the highest. Verification test proved that it had the best adsorbability. Conclusion: The rice-washed water can be prepared with the flour of long glutinous rice.

Detection of DNA polymerase λ activity during seed germination and enhancement after salinity stress and dehydration in the plumules of indica rice (Oryza sativa L.).

DNA polymerase λ (DNA pol λ) is the only reported X-family DNA polymerases in plants and has been shown to play a significant role in dry quiescent seeds, growth, development and nuclear DNA repair. cDNA for DNA pol λ has been reported in Arabidopsis and japonica rice cultivar and has been characterized from E. coli expressed protein, but very little is known about its activity at protein level in plants. The enzymatic activity of DNA pol λ was studied in dry, imbibed and during different germination stages of indica rice IR-8 (salt sensitive) by in-gel activity assay to determine its physiological role in important stages of growth and development. The upstream sequence was also analyzed using plantCARE database and was found to contain several cis-acting elements, including light responsive elements, dehydration responsive elements, Myb binding sites, etc. Hence, 4-day-old germinating seedlings of IR29, a salt-sensitive, but high yielding indica rice cultivar and Nonabokra, a salt-tolerant, but low yielding cultivar were treated with water (control) or 250 mM NaCl or 20% polyethyleneglycol-6000 for 4 and 8 h. The protein was analyzed by in vitro DNA pol λ activity assay, in-gel activity assay and Western blot analysis. DNA pol λ was not detected in dry seeds, but enhanced after imbibition and detectable from low level to high level during subsequent germination steps. Both salinity and dehydration stress led to the enhancement of the activity and protein level of DNA pol λ, as compared to control tissues. This is the first evidence of the salinity or dehydration stress induced enhancement of DNA pol λ activity in the plumules of rice (Oryza sativa L.) cultivars.

Protocol for in vitro somatic embryogenesis and regeneration of rice (Oryza sativa L.).

Development of highly efficient and reproducible plant regeneration system has tremendous potential to provide improved technology to assist in genetic transformation of indica rice cultivars for their further exploitation in selection. For the development of a highly reproducible regeneration system through somatic embryogenesis, mature embryos of highly popular rice cultivars i.e., Govind (for rainfed areas), Pusa Basmati-1 (aromatic basmati) and Jaya (for irrigated areas) were used. Optimum callus formation (%) to MS medium supplemented with 2, 4-D was obtained at 12.0 mM in Govind, 14.0 mM in Jaya and 15.0 mM in Pusa Basmati-1. All the cultivars showed good proliferation on MS medium without hormone. In Govind, highest embryogenic response was observed in MS medium supplemented with 2, 4-D (0.4 mM) + kinetin (0.4 mM), while in Pusa Basmati-1 with 2, 4-D (0.4 mM) + kinetin (2.0 mM) and in Jaya on hormone-free MS medium. Excellent embryo regeneration in Govind was observed on MS medium supplemented with low concentrations (1.1 mM) of BAP or hormone-free MS medium, while in Pusa Basmati-1 and Jaya embryogenesis was observed on MS medium supplemented with higher concentration of BAP (2.2 mM). Similarly, maximum plantlets with proliferated roots were observed in Govind on hormone-free MS medium, while in Pusa Basmati-1 and Jaya on MS medium supplemented with high concentration of NAA (4.0 mM). Developed plantlets were further successfully acclimatized and grown under pot culture up to maturity. Further the yield potential of in vitro developed plants was accessed at par to the direct seeded one under pot culture. Present, protocol standardizes somatic embryogenesis and efficient regeneration of agronomically important, high yielding and diverse indica rice cultivars which can be utilized as an efficient tool for molecular studies and genetic transformation in future.

Analysis of the genetic relationships from different genetic systems between the amylose content and the appearance quality of indica rice across environments

The genetic relationships between amylose content (AC) and appearance quality traits of indica rice (Oryza sativa L.) were investigated using conditional analysis and unconditional analysis in present experiment. The results from the unconditional analysis indicated that AC of rice positively correlated with brown rice (BR, i.e., dehulled but unmilled rice) length (BRL), width (BRW) and thickness (BRT), but was negatively correlated with the ratio of length to width (RLW). The conditional analysis showed that weight of brown rice (WBR) negatively affected the genetic relationships between AC and the appearance quality traits of rice except between AC and BRW, while the genetic relationships between AC and most appearance quality traits were negatively affected by protein content (PC). However, these influences were not apparent due to the impact of WBR or PC on the most covariance components of the different genetic systems between AC and the appearance quality traits. The conditional analysis showed that it was possible to improve AC while significantly reduce BRL and BRT under maintaining WBR. Furthermore, AC could be improved when BRL was reduced under maintaining PC, but BRW and BRT could be significantly increased.