Comparative analysis of eating quality and yield of selected non-waxy red-pericarp aromatic rice mutants

Red-pericarp variety Kuanfu waxy aroma is highly valued for its grain quality in Taiwan, but it has undesirable traits of awned rough grain and taller plant height.  The present study compared the palatability of cooked rice grains and yields of Kuanfu waxy aroma and its ten NaN3-induced awnless non-waxy aromatic M6-generation mutants developed through single-seed-descent selection (from M2 to M6 generation) plus a non-waxy aromatic rice variety TNG71 (reference variety with good eating quality).  The palatability of cooked rice grains was assessed by using a rice taste meter.  Results indicated that all the mutants exhibited awnless grain traits and reduced plant height.  PCR analyses confirmed the expression of fragrance (fgr) gene in these mutants.  Significant differences in the palatability of cooked rice were also observed among the mutants with AM-425 (70.45) and AM-430 (73.75) having higher palatability scores than TNG71 (69.32).  Mutant AM-425 also had higher aroma sensory score (1.33) than TNG71 (1.17).  Two years yield trials indicated that AM-425 and AM-430 significantly out-yielded Kuanfu waxy aroma and can be recommended to rice growers.

Using RAPD markers to predict polyphenol content in aerial parts of Echinacea purpurea plants

BACKGROUND:Echinacea purpurea (L.) Moench is in increasing demand worldwide owing to its medicinal value, resulting from the combined effects of several phytochemicals. In the present study, the polymerase chain reaction-amplified randomly amplified polymorphic DNA (RAPD) markers generated from 45 pre-selected primers were used to predict the contents of total phenol, caffeoyl phenol and alkamide8 + 9 (alkamide 8+ alkamide 9) in aerial parts of 70 E. purpurea accessions through stepwise regression analysis. The contents of these phytochemicals were also analyzed chemically. RESULTS: In the first trial, 16 polymorphic fragments generated by pre-selected RAPD primers showed significant correlations with the examined phytochemical traits in 59 accessions. Phytochemical traits in leaves and florets of another 11 accessions were further analyzed chemically, and the data were compared to the phytochemical data predicted using the regression equations derived from first trial. Statistical analyses revealed significant correlations in total phenol level between predicted and actual values for leaves and florets in these 11 accessions. CONCLUSION: RAPD markers coupled with stepwise regression analysis can be considered as an initial screening method for identifying E. purpurea accessions with high total phenol content in aerial parts of the plants prior to assessing their agronomic performance in the field. Copyright © 2009 Society of Chemical Industr

Genetic diversity in NaN3-induced common bean mutants and commercial varieties detected by AFLP

The analysis of Amplified Fragment Length Polymorphism (AFLP) was used to estimate genetic diversity in common bean (Phaseolus vulgaris L.) variety Hwachia and in 34 NaN3-induced mutants and 11 commercial varieties introduced from China. Eight primer combinations generated 516 DNA fragments of the tested mutants and introduced varieties, of which 448 fragments were polymorphic. The calculated Jaccard similarity coefficients based on AFLP data ranged from 0.47 to 0.84. The molecular profiles obtained from eight AFLP primer pairs indicated a high genetic diversity among Hwachia, NaN3-induced mutants and introduced varieties. The extent of genetic variation was slightly higher between Hwachia and NaN3-induced mutants than between Hwachia and introduced commercial varieties. These results, supported by cluster analysis, suggest that NaN3-induced mutagenesis effectively broadens the genetic diversity of common bean varieties. Some of the produced mutants could be useful as sources of variation to develop new improved common bean varieties

Comparisons of flavonoids and anti-oxidative activities in seed coat, embryonic axis and cotyledon of black soybeans

Flavonoids contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activities and the ferric-reducing antioxidant power (FRAP) were compared in three black soybean varieties CRWD, Tainan 3 and Tainan 5. Varietal differences in antioxidant contents existed among the tested varieties. Variety CRWD accumulated more total phenolics (7.49 mg g−1) and isoflavones (1.77 mg g−1) than varieties Tainan 3 (7.05 mg g−1 total phenolics and 1.58 mg g−1 isoflavones) and Tainan 5 (4.38 mg g−1 total phenolics and 0.63 mg g−1 isoflavones). CRWD also accumulated more proanthocyanidins in seed coat than Tainan 3 and Tainan 5. CRWD also demonstrated greater DPPH and FRAP activities than the other two cultivars. Stepwise regressions indicated that both DPPH and FRAP activities were correlated well with the total contents of phenolics and flavonoids, with total phenolics being the most important anti-oxidative factor. The present results indicate that CRWD has greater anti-oxidative responses than Tainan 3 or Tainan 5, and is useful in functional food and other applications

PARTICLE SIZE AND TEMPERATURE EFFECTS ON ANTIOXIDANT BY-PRODUCT ISOLATED FROM LEAF GUM EXTRACT OF MESONA PROCUMBENS HEMSL

A water extraction procedure for isolating antioxidants from dried aerial tissue of Mesona procumbens Hemsl. prior to leaf gum/starch composite gel preparation was developed, along with investigation of its antioxidative activities. The results showed that the highest contents of total phenolics and flavonoids were isolated from the dried aerial tissues when they were extracted under 100C for 2 h using the dried materials ground to 75-µm particle size. This water extract also had the highest antioxidative responses, as determined by 2,2-diphenyl-1-picrylhydrazy scavenging, ferric reducing antioxidant power, 2,2-azino-bis[3-ethyl-benzthiazoline-6-sulfonic acid] radical-scavenging, superoxide-scavenging and lipid peroxidation inhibition activities. The water extract produced under 100C condition also showed the greatest gel hardness and gel strength (prepared by using 2% cassava starch). Thus, the extracted antioxidants from aerial tissues of M. procumbens Hemsl. could be considered for some commercial applications

Comparisons and selection of rice mutants with high iron and zinc contents in their polished grains that were mutated from the indica type cultivar IR64

Developing rice varieties biofortified with iron (Fe) and zinc (Zn) is an important strategy to alleviate nutritional deficiencies in developing countries, where polished rice is consumed as the staple food. In this study, the contents of several macro- and micro-minerals in polished rice grains of cultivar IR64 and its 254 sodium azide-induced mutants (M8 generation) were assessed. The results indicated that the contents of potassium, phosphorus, calcium, magnesium, iron, manganese, copper, and zinc varied among the tested mutants. The polished rice grains of mutants M-IR-75 and M-IR-58 accumulated more Fe (28.10 and 27.26 mg kg−1, respectively) than cultivar IR64 (3.90 mg kg−1). Mutant M-IR-75 also produced higher yield (average of 8.65 ton ha−1 over two crop seasons) than cultivar IR64 (average of 7.27 ton ha−1). Mutants M-IR-180, M-IR-49 and M-IR-175 contained more Zn (26.58, 28.95 and 26.16 mg kg−1, respectively) than cultivar IR64 (16.00 mg kg−1), but only mutant M-IR-180 showed a grain yield comparable to cultivar IR64. Thus, the mutant M-IR-75 can be recommended to rice growers to produce Fe-rich rice grains. Additionally, the high-Fe (M-IR-75 and M-IR-58) and high-Zn (M-IR-180, M-IR-49 and M-IR-175) mutants can be used as genetic resources for rice improvement programs

In vitro inhibitory effects of cranberry bean (Phaseolus vulgaris L.) extracts on aldose reductase, α-glucosidase and α-amylase

The in vitro inhibitory activities of different seed extracts prepared from cranberry bean mutant SA-05 and its wild-type variety Hwachia against aldose reductase, α-glucosidase and α-amylase were examined. The results indicated that the polyphenolics-rich extracts obtained using 800 g kg−1 methanol and 500 g kg−1 ethanol demonstrated inhibitory activities against aldose reductase (IC50 of 0.36–0.46 mg mL−1) and α-glucosidase (IC50 of 1.32–1.94 mg mL−1). The 500 g kg−1 ethanol extracts also showed α-amylase inhibitory activities (IC50 of 70.11–80.22 μg mL−1). Subsequent extracts, prepared further with NaCl and H2O from precipitates of 800 g kg−1 methanol or 500 g kg−1 ethanol extracts, exhibited potent α-amylase inhibitory activities (IC50 of 17.68–38.68 μg mL−1). A combination of 500 g kg−1 ethanol extraction plus a subsequent H2O extraction produced highest polyphenolics and α-amylase inhibitors. The SA-05 α-amylase inhibitor extracts showed greater inhibitory activities than that of Hwachia. Thus, cranberry bean mutant SA-05 is an advantageous choice for producing anti-hyperglycaemic compounds