Application of derivative ratio spectrophotometry for determination of β-carotene and astaxanthin from Phaffia rhodozyma extract

INTRODUCTION Carotenoids are a class of natural fat-solublepigments generally found in plants, algae, and pho-tosynthetic bacteria, where they play a critical role inthe photosynthetic process. Carotenoids also exist insome non-photo-synthetic bacteria, yeasts, and moldswhere they may carry out a protective functionagainst damages by light and oxygen. Although ani-mals can not synthesize carotenoids within theirbodies, they can intake carotenoids from their dietsleading to bright meat col…     

Genetic mapping of quantitative trait loci associated with β-amylase and limit dextrinase activities and β-glucan and protein fraction contents in barley

High malting quality of barley (Hordeum vulgate L.) relies on many traits, such as β-amylase and limit dextrinase activities and β-glucan and protein fraction contents. In this study, interval mapping was utilized to detect quantitative trait loci (QTLs) affecting these malting quality parameters using a doubled haploid (DH) population from a cross of CM72 (six-rowed) by Gairdner (two-rowed) barley cultivars. A total of nine QTLs for eight traits were mapped to chromosomes 3H, 4H, 5H, and 7H. Five of the nine QTLs mapped to chromosome 3H, indicating a possible role of loci on chromosome 3H on malting quality. The phenotypic variation accounted by individual QTL ranged from 8.08% to 30.25%. The loci of QTLs for β-glucan and limit dex-trinase were identified on chromosomes 4H and 5H, respectively. QTL for hordeins was coincident with the region of silica eluate (SE) protein on 3HS, while QTLs for albumins, globulins, and total protein exhibited overlapping. One locus on chromosome 3H was found to be related to β-amylase, and two loci on chromosomes 5H and 7H were found to be associated with glutelins. The identification of these novel QTLs controlling malting quality may be useful for marker-assisted selection in improving barley malting quality.     

Relationship between malt qualities and β-amylase activity and protein content as affected by timing of nitrogen fertilizer application

The effects of different timing of N fertilizer application at the same rate on grain β-amylase activity, protein concentration, weight and malt quality of barley were studied. Grain β-amylase activity and protein concentration were significantly higher in treatments where all top-dressed N fertilizer was applied at booting stage only or equally applied at two-leaf stage and booting stage than in the treatment where all top-dressed N fertilizer was applied at two-leaf age stage only. On the other hand, grain weight and malt extract decreased with increased N application at booting stage. There were obvious differences between barley varieties and experimental years in the grain and malt quality response to the timing of N fertilizer application. It was found that grain protein concentration was significantly and positively correlated with β-amylase activity, but significantly and negatively correlated with malt extract and Kolbach index. The effect of grain protein concentration on malt quality was predominant over the effect of grain β-amylase activity.     

Stability and cytotoxicity of angiotensin-I-converting enzyme inhibitory peptides derived from bovine caseinWei WU,Pan-pan YU,Feng-yang ZHANG,Hong-xia CHE,Zhan-mei JIANG简

This study investigated the effect of heat treatment combined with acid and alkali on the angiotensin-Iconverting enzyme (ACE) inhibitory activity of peptides derived from bovine casein. The free amino group content, color, and cytotoxicity of the peptides were measured under different conditions. When heated at 100 °C in the pH range from 9.0 to 12.0, ACE inhibitory activity was reduced and the appearance of the peptides was significantly darkened. After thermal treatment in the presence of acid and alkali, the free amino group content of ACE inhibitory peptides decreased markedly. High temperature and prolonged heating also resulted in the loss of ACE inhibitory activity, the loss of free amino groups, and the darker coloration of bovine casein-derived peptides. However, ACE inhibitory peptides, within a concentration range of from 0.01 to 0.2 mg/ml, showed no cytotoxicity to Caco-2 and ECV-304 cell lines after heat treatment. This indicated that high temperature and alkaline heat treatment impaired the stability of bovine casein-derived ACE inhibitory peptides.     

From teaching from the heart to teaching with a heart: Segmenting filipino college students’ views of their teachers’ caring behavior and their orientations as cared-for individuals

Caring, as a universal human phenomenon, should permeate elementary, secondary and tertiary level instruction. The practice of teaching, especially at the tertiary level, is not only substantial and procedural but relational as well. To teach with a heart is the essence that makes teaching a form of caring. When teaching is viewed as a form of caring, teachers become relational geniuses in their own right. This study is an attempt to segment Filipino college students’ views (n=1000) of their teachers’ caring behavior and their orientations as cared-for individuals. The identified clusters of teacher roles that indicate caring behavior imply that acts of teaching become acts of caring depending on how the teachers, theefficient cause of education, perform their ordinary tasks in the context ofextraordinariness. Such extraordinariness spells out a big difference in the way teachers practice the so-calledsingle loop caring or caring visibility anddouble- loop caring or caring presence. The former refers to teaching from the heart while the latter pertains to teaching with a heart. Interestingly, the extent to which teachers’ caring behavior is felt and experienced by the students positively shapes their orientations as cared-for individuals.