Aroma extract dilution analysis of a beeflike process flavor from extruded enzyme-hydrolyzed soybean protein

Aroma-active compounds from a beeflike process flavor, produced by extrusion of enzyme-hydrolyzed vegetable protein (E-HVP), were analyzed using aroma extract dilution analysis. The number of aroma-active compounds and the aroma intensity were increased by the addition of aroma precursors prior to extrusion. The most intense compound was 2-methyl-3-furanthiol having a cooked rice/vitamin-like/meaty aroma note. Several sulfur-containing furans, such as 2-methyl-3-(methylthio)furan, 2-methyl-3-(methyldithio)furan, and bis(2-methylfuryl)disulfide, were detected with high flavor dilution (FD) factors. Some pyrazines, such as 2-ethyl-3,5-dimethylpyrazine, 2,6-diethylpyrazine, and 3,5-diethyl-2-methylpyrazine, also had high FD factors. It is hypothesized that sulfur-containing amino acids and thiamin were important precursors in aroma formation in process flavor from E-HVP.     

Optimal protocol for mass propagation of Aloe vera

We established an advanced protocol for in vitro propagation of Aloe vera via comparison of basal media, sucrose contents, growth hormone combinations, and additional supplementation with various polyamines. The maximal number and growth of shoots after 5 weeks was obtained using MS media including 30 g L^?1 sucrose supplemented with 1.0 mg L^?1 BA and 0.1 mg L^?1 NAA. To improve shoot production, various concentrations of putrescine, spermidine, and spermine were added under optimal growth hormone conditions (MS media supplemented with 30 g L^?1 sucrose, 1.0 mg L^?1 BA, and 0.1 mg L^?1 NAA). Maximal shoot number and growth after 5 weeks were achieved with supplementation of 50 mg L^?1 spermidine. Regenerated plants were successfully acclimatized in soil with 100% efficiency. Cytogenetic inspection revealed that the regenerated plants maintained intact chromosomes identical to those of plants grown in field conditions. This protocol provides a valuable alternative for mass production of elite Aloe vera.     

Case study: cost-effective image analysis method to study drought stress of soybean in early vegetative stage

Journal of Crop Science and Biotechnology - There are many applications of image-based analysis for phenotyping agronomic traits. However, they are inappropriate or difficult to operate due to lack...     

Selection of soybean mutant lines with altered seed coat colour and their antioxidant activity

In this study, the flavonoid and isoflavone contents in four checks with seed coat colour altered from yellow to black were determined, and their antioxidant activity was measured. Three anthocyanins (delphinidin‐3‐O‐β‐D‐glucoside, D3G; cyanidin‐3‐O‐β‐D‐glucoside, C3G; and petunidin‐3‐O‐β‐D‐glucoside, Pt3G) were detected in the four checks, while their controls (cvs. ‘Danbaek’ and ‘Daepung’) were not found. Among them, D‐16 derived from cv. ‘Danbaek’ showed the highest anthocyanin contents. The isoflavone contents of all checks showed lower levels compared to their controls. Among six isoflavones, glycitein was only detected in DP‐39. To analyse the radical scavenging activities among the four checks, we conducted DPPH, FRAP and UWLA assays. Significant differences in antioxidant activities were obtainable in the four checks, which contained significant differences in levels of anthocyanins and isoflavones. Based on these results, gamma irradiation may change the isoflavone and anthocyanin contents of soybean. Our four checks selected in this study may be useful for breeding soybean varieties to alter their nutritional values.     

Inheritance of (1–3)(1–4)-beta-D-glucan content in barley (<Emphasis Type="Italic">Hordeum vulgare</Emphasis> L.)

β-glucan is the soluble dietary fiber component and occurs at its highest in barley. This study aims to evaluate the inheritance of β-glucan content in barley grains and to map quantitative trait loci (QTL) associated with this trait. F₅-derived 107 lines from the cross of the six-rowed waxy hulless barley, ‘Yonezawa Mochi’ and the six rowed non-waxy hulless barley,’ Neulssalbori’ were measured for their agronomic traits and β-glucan level at four different environments. These recombinant lines showed significant genotypic variation (P < 0.01) and normal distribution for β-glucan content with a range of 43.6–62.1 g kg⁻¹ across environments. A significant genotype-by-environment interaction was also found. The broad-sense heritability estimates for β-glucan content ranged from 0.42 to 0.82 across environments. Using one-factor analysis and composite interval mapping, a main effect of QTL associated with β-glucan content was identified in the genomic region near waxy gene (wx) and HVM4 on chromosome 7H. The major QTL at this region explained on average 44.4% of the variation for the mean of β-glucan content across environments with LOD values that ranged from 5.7 in Suwon in 2001 to 13.9 in Suwon in 2003. Two minor QTLs were identified but their significance of association with β-glucan content was inconsistent across environments.     

Medicago truncatula DMI1 required for bacterial and fungal symbioses in legumes

Legumes form symbiotic associations with both mycorrhizal fungi and nitrogen-fixing soil bacteria called rhizobia. Several of the plant genes required for transduction of rhizobial signals, the Nod factors, are also necessary for mycorrhizal symbiosis. Here, we describe the cloning and characterization of one such gene from the legume Medicago truncatula. The DMI1 (does not make infections) gene encodes a novel protein with low global similarity to a ligand-gated cation channel domain of archaea. The protein is highly conserved in angiosperms and ancestral to land plants. We suggest that DMI1 represents an ancient plant-specific innovation, potentially enabling mycorrhizal associations.     

Comparison of in vitro vitellogenin syntheses by three phenols in primary cultures of Chinese minnow, Rhynchocypris oxycephalus hepatocytes

The in vitro effects of bisphenol-A (BPA), nonylphenol (NP) and 4-tert-octylphenol (OP) on vitellogenin (VTG) synthesis were examined using primary cultures of Chinese minnow, Rhynchocypris oxycephalus hepatocytes. In vitro VTG syntheses were induced by exposure to 10^?5 M of BPA and 10^?4 M of both NP and OP, suggesting that BPA had the highest estrogenic potential among the three phenols.     

EDCs‐induced glucocorticoid receptor related genes expression of the river pufferfish,Takifugu obscurus

Endocrine disrupting chemicals (EDCs) are of substantial concern when contaminating waters. We studied gene expression of larvae from river pufferfish, Takifugu obscurus exposed to EDCs. We cloned the full‐ or partial‐length cDNA sequence of genes related to the cortisol pathway, such as the glucocorticoid receptor (GR), mineralocorticoid receptor (MR), heat shock protein (HSP) 70 and 90, phosphoenolpyruvate carboxykinase (PEPCK) and the FK506‐binding protein 4 (FKBP52). The tissue and time‐dependent expression of mRNA was studied by real‐time PCR in T. obscurus exposed to two representative EDCs (bisphenol‐A and 4‐tert‐octylphenol). HSP70, HSP90, MR and FKBP52 mRNA expression level was much higher than GR and PEPCK expression. GR mRNA expression level was significantly upregulated after 48 h in both EDC‐treated fish groups compared with the control. Both groups also showed down‐regulation patterns after 48 h. The initial expression of PEPCK in both groups was down‐regulated after 24 h. In the bisphenol‐A treated group, the expression of FKBP52 showed substantially high up‐regulation from 6 to 48 h after exposure, and then strikingly reduced its expression level at 72 h. Our results provide insights into the EDCs metabolizing system of T. obscurus and offers baseline information for further research related to the possible use as a bio‐indicator of this commercially important aquaculture fish species.     

Metal ion adsorbability of electrospun wool keratose/silk fibroin blend nanofiber mats

In this study, electrospun wool keratose (WK)/silk fibroin (SF) blend nanofiber was prepared and evaluated as a heavy metal ion adsorbent which can be used in water purification field. The WK, which was a soluble fraction of oxidized wool keratin fiber, was blended with SF in formic acid. The electrospinnability was greatly improved with an increase of SF content. The structure and properties of WK/SF blend nanofibers were investigated by SEM, FTIR, DMTA and tensile test. Among various WK/SF blend ratios, 50/50 blend nanofiber showed an excellent mechanical property. It might be due to some physical interaction between SF and WK molecules although FTIR result did not show any evidence of molecular miscibility. As a result of metal ion adsorption test, WK/SF blend nanofiber mats exhibited high Cu²⁺ adsorption capacity compared with ordinary wool sliver at pH 8.5. It might be due to large specific surface area of nanofiber mat as well as numerous functional groups of WK. Consequently, the WK/SF blend nanofiber mats can be a promising candidate as metal ion adsorption filter.     

Determination of optimal temperature(s) in juvenile red‐spotted grouper Epinephelus akaara (Temminck & Schlegel) based on growth performance and stress responses

This study sought to determine the optimal temperature(s) for aquaculture of juvenile red‐spotted grouper Epinephelus akaara (Temminck & Schlegel) (mean initial BW: 3.1 g). Growth performance, insulin‐like growth factor 1 (IGF‐1) expression and thermal stress responses (plasma cortisol, glucose, and hepatic heat shock protein 60 expression) were evaluated at three constant temperatures (24°C, 26°C and 28°C) in a 2‐week trial. At the end of the trial, final BW was significantly higher at 26°C and 28°C than at 24°C (p < 0.05); a quadratic regression analysis of final BW showed the optimum temperature for growth was 27.5°C (p < 0.05, R² = 0.806). The highest hepatic IGF‐1 expression was observed at 26°C (p < 0.05). On the other hand, hepatic heat shock protein 60 expression was highest at 28°C (p < 0.05), suggesting thermal stress. In conclusion, temperature optima, which support excellent growth but induce minimal thermal stress, was 26°C. This fine information within a narrow temperature range is expected to give empirical information for red‐spotted grouper farmers to sustain maximal production efficiency with avoiding thermal stress and to determine the future location of production, especially in consideration of arising seawater temperatures.