Reduced Germination and Seedling Vigor of Weeds with Root Extracts of Maize and Soybean,and the Mechanism Defined as Allelopathic

Journal of Crop Science and Biotechnology - Due to the negative consequences of synthetic herbicides use and their reducing effectiveness due to development of resistant weeds, promotion of...     

Discrimination of intact and injured Listeria monocytogenes by Fourier transform infrared spectroscopy and principal component analysis

Fourier transform infrared spectroscopy (FT-IR, 4000-600 cm(-)(1)) was used to discriminate between intact and sonication-injured Listeria monocytogenes ATCC 19114 and to distinguish this strain from other selected Listeria strains (L. innocua ATCC 51742, L. innocua ATCC 33090, and L. monocytogenes ATCC 7644). FT-IR vibrational overtone and combination bands from mid-IR active components of intact and injured bacterial cells produced distinctive "fingerprints" at wavenumbers between 1500 and 800 cm(-)(1). Spectral data were analyzed by principal component analysis. Clear segregations of different intact and injured strains of Listeria were observed, suggesting that FT-IR can detect biochemical differences between intact and injured bacterial cells. This technique may provide a tool for the rapid assessment of cell viability and thereby the control of foodborne pathogens.     

Changes in allergenicity and digestibility of squid tropomyosin during the Maillard reaction with ribose

The effect of the Maillard reaction on the allergenicity of squid tropomyosin (TM) was investigated. When TM was reacted with ribose (TM-ribose), its human-specific IgE-binding ability decreased markedly and alpha-chymotryptic digestibility of TM was also altered at the early stage of the Maillard reaction. On the other hand, the modification of the lysine residues in TM using 2,4,6-trinitrobenzenesulfonic acid had no effect on the allergenicity and alpha-chymotryptic digestibility of TM. Therefore, the structural change in TM induced by the Maillard reaction would cause the reduction of the allergenicity, rather than the block of lysine residues. Although peptic digestion diminished the specific IgE-binding ability of TM, the reduction of the allergenicity by the Maillard reaction remained after peptic digestion. These results suggest that hypersensitive reaction of TM-ribose in the human body might be lower than that of native TM.     

Effects of diosmin, a flavonoid glycoside in citrus fruits, on P-glycoprotein-mediated drug efflux in human intestinal Caco-2 cells

The effects of citrus flavonoids on P-glycoprotein (P-gp)-mediated drug efflux were examined in human intestinal Caco-2 cells. The cellular accumulation of rhodamine-123 was measured using 10 citrus flavonoids for preliminary screening. Among the flavonoids tested, diosmin significantly increased the accumulation of rhodamine-123 in Caco-2 cells. In the bidirectional transport of digoxin, diosmin increased the apical-to-basal (A-to-B) transport but decreased the basal-to-apical (B-to-A) transport in both concentration- and time-dependent manners. The digoxin transport ratio (B-A/A-B) was estimated to be 2.3 at a concentration of 50 microM of diosmin, which was significantly lower than the 15.2 found in the control. The apparent Ki values for P(app,A-B) and P(app,B-A) were 16.1 and 5.7 microM, respectively. These results demonstrated that diosmin effectively inhibited the P-gp-mediated efflux in Caco-2 cells. Diosmin is one of the main components in citrus fruits, and the intake of food supplements containing this compound may potentially increase the absorption of drugs able to act as P-gp substrates. The clinical relevance of this interaction should be further evaluated using in vivo experiments.     

Effect of light on endogenous levels of gibberellin and abscisic acid in seed germination of photoblastic weedy rice (Oryza sativa L.)

The effect of red (R) and R/far-red (FR) lights on endogenous gibberellin (GA) and abscisic acid (ABA) content was first investigated during the germination of photoblastic black-hulled weedy rice (PBWR) seeds. The R light-treated PBWR seeds germinated after 36–48 h and germination was increased to 63% at 72 h. However, the FR light-treated seeds after R light treatment, suppressed the R light effect showing only 11% germination even at 72 h after the light treatment. The PBWR seed treated with R light rapidly increased the endogenous level of GA₁ to about 200 times at 12 h before seed germination as compared with R/FR (control) which suppressed the effect of R light. The contents of other GAs like GA₁₂, GA₅₃, GA₁₉, GA₂₀, and GA₈ were not affected by the R light irradiation. These results showed that the major biosynthetic pathway of GAs in PBWR seeds is the early 13-hydroxylation pathway leading to GA₁, which was suggested to be physiologically active in the PBWR seed germination. The decrease in the level of ABA in the R light-treated seeds was greater than the R/FR light-treated seeds, indicating that the balance of endogenous GA1 and ABA is responsible for the induction of germination in the PBWR seed.     

Effects of supplementing Barodon,Bacillus subtilis,and Ampbio on growth performance,biochemical metabolites,and hormone levels in Korean native heifers

An experiment was conducted to evaluate the effects of supplementing feed additives of Barodon®, effective microorganism® (Bacillus (B.) subtilis), and Ampbio® on the growth performance, blood metabolites, stress, and reproductive hormone levels of Korean native heifers. A total of 48 Korean native heifers were assigned to four groups with 6 heifers in each group. The groups were control, Barodon (0.2%), beneficial microorganism (1%), and Ampbio (1%). Animals in all groups were fed a basal diet composed of selected feed additives and water ad libitum for 99 days. Results showed that there are significant changes in body weight and daily gain in the Ampbio-supplemented group as compared with the control and other feed additives groups (p?<?0.05). The increased level of feed intake (7.30?±?0.03 kg) and feed requirements (10.81?±?0.52 kg) was observed in the Ampbio-fed group followed by the effective microorganism (EM), Barodon, and control groups. There were no significant changes in albumin, glucose, glutamic oxaloacetic transaminase (SGOT), serum pyruvic transaminase (SGPT), and total protein level, but the decreased levels of total cholesterol and triglycerides and the increased level of blood urea nitrogen were noted in the Ampbio-fed group as compared with the control and other feed additive groups. The reduced level of cortisol (p?<?0.05) and elevated levels of progesterone and estradiol (p?>?0.05) were noted in the Ampbio-fed group as compared to the other feed additive groups. It is therefore concluded that incorporation of Barodon, EM (B. subtilis), and Ampbio in the recommended diet improved the growth and health performance of Korean native heifers.

     

Effect of oxygen on volatile and sensory characteristics of Cabernet Sauvignon during secondary shelf life

The oxidation of Cabernet Sauvignon wines during secondary shelf life was studied by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-quadrupole mass spectrometry (GC-qMS) and sensory tests, with the support of multivariate statistical analyses such as OPLS-DA loading plot and PCA score plot. Four different oxidation conditions were established during a 1-week secondary shelf life. Samples collected on a regular basis were analyzed to determine the changes of volatile chemicals, with sensory characteristics evaluated through pattern recognition models. During secondary shelf life the separation among collected samples depended on the degree of oxidation in wine. Isoamyl acetate, ethyl decanoate, nonanoic acid, n-decanoic acid, undecanoic acid, 2-furancarboxylic acid, dodecanoic acid, and phenylacetaldehyde were determined to be associated with the oxidation of the wine. PCA sensory evaluation revealed that least oxidized wine and fresh wine was well-separated from more oxidized wines, demonstrating that sensory characteristics of less oxidized wines tend toward "fruity", "citrous", and "sweetness", while those of more oxidized wines are positively correlated with "animal", "bitterness", and "dairy". The study also demonstrates that OPLS-DA and PCA are very useful statistical tools for the understanding of wine oxidation.     

Effect of maillard reaction on allergenicity of scallop tropomyosin

Scallop tropomyosin (TM), the major allergen of shellfish, was prepared from adductor muscles and reacted with four reducing sugars to investigate the effect of the Maillard reaction on the allergenicity of TM. The IgE-binding ability of TM increased significantly with the progress of the reaction with glucose, ribose, and maltose, but not with maltotriose. The allergenicity was enhanced at the early stage of the Maillard reaction, and the trend of the effect depended on the type of reducing sugar used. 2,4,6-Trinitrobenzenesulfonic acid treatment of the lysine residues in TM showed that the protein surface charge resulting from the Maillard reaction had no effect on the enhancement of the allergenicity. Thus, the change in the allergenicity would be closely related to the structural change caused by the Maillard reaction.