Antioxidant activity of black currant anthocyanin aglycons and their glycosides measured by chemiluminescence in a neutral pH region and in human plasma

The antioxidant activity of nine anthocyanin glycosides was measured in a neutral pH region using a chemiluminescence (CL) emission system in the presence of an H(2)O(2)-acetaldehyde system, and the intensities were found to be affected by three factors, pH value and both moieties of the aglycon and C-3 sugar. With an increase in pH from 4.0 to 9.0, the CL intensities increased from pH 5.0, reached their maxima at pH 6.0-7.0, and decreased at pH 9.0. Comparison of the intensities among the 3-glucosides with five different aglycons and the 3-glycosides with three different sugar moieties at C-3 showed that their strongest intensities were given by the delphinidin aglycon and 3-rutinosyl moiety, respectively. Monitoring of the CL intensity of human blood plasma for 8 h after oral administration of black currant anthocyanins (BCA) showed a rapid increase until 2 h, and a significant difference (P < 0.05) was recognized at 1-8 h.     

Oxidative cleavage of lignin aromatics during chlorine bleaching of kraft pulp

Methanol liberation and methoxyl loss during chlorine bleaching of softwood kraft pulp were quantitatively investigated to estimate the degree of structural modification of lignin aromatics. An increase in the chlorine multiple led to enhanced methoxyl loss from lignin. Our result, using pH-adjusted chlorine water (pH 5.7), by which chlorination under oxidation-favorable conditions was achieved, strongly supported the importance of the oxidation reaction by chlorine during delignification and lignin degradation. It was also suggested that methanol can be produced not only via catalytic hydrolysis by chlorine but via oxidative cleavage of the ether bond as well. The infrared spectrum of chlorolignins suggested that chlorine oxidation can open aromatic rings to muconic acid derivatives without cleaving ether bonding of the methoxyl group. No straight relation between the methoxyl content and the kappa number of chlorinated pulps was shown. The methoxyl content of bleached kraft pulps subjected to successive chlorination and alkali extraction showed a good relation with the kappa number. This means that almost all the portions of the oxidatively modified lignin structure were successfully removed during these treatments, and the aromatic structures of residual lignin in chlorinated and alkali-extracted pulps were thought to remain intact.Part of this paper was presented at the 46th Annual Meeting of the Japan Wood Research Society, Kumamoto, April 1996; the 10th International Symposium on Wood and Pulping Chemistry, Yokohama, June 1999; and the 67th Pulp and Paper Research Conference, Tokyo, June 2000     

Anti-lipopolysaccharide antibody administration mitigates ruminal lipopolysaccharide release and depression of ruminal pH during subacute ruminal acidosis challenge in Holstein bull cattle

The effects of anti-lipopolysaccharide (LPS) antibody on rumen fermentation and LPS activity were investigated during subacute ruminal acidosis (SARA) challenge. Eleven Holstein cattle (164 ± 14 kg) were used in a 3 × 3 Latin square design. Cattle were fed a roughage diet on days −11 to −1 (pre-challenge) and day 2 (post-challenge), and a high-grain diet on days 0 and 1 (SARA challenge). For 14 days, 0-, 2-, or 4-g of anti-LPS antibody was administered once daily through a rumen fistula. Ruminal pH was measured continuously, and rumen fluid and blood samples were collected on days −1, 0, 1, and 2. Significantly lower ruminal LPS activity on day 1 was observed in the 2- and 4-g groups than those in the 0-g group. In addition, significantly higher 1-hr mean ruminal pH on SARA challenge period (days 0 and 1) was identified in the 4-g group than in the 0-g group. However, rumen fermentation measurements (total volatile fatty acid [VFA], VFA components, NH₃-N and lactic acid) and peripheral blood metabolites (glucose, free fatty acid, beta-hydroxybutyrate, total cholesterol, blood urea nitrogen, aspartate aminotransferase and gamma-glutamyl transferase) were not different among the groups during the experimental periods. Therefore, anti-LPS antibody administration mitigates LPS release and pH depression without the depression of rumen fermentation and peripheral blood metabolites during SARA challenge in Holstein cattle.     

Estimation of nutrient excretion factors of broiler and layer chickens in Japan

We estimated the nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg) excretion factors of broiler and layer chickens in Japan, using two approaches and the latest data available. In the top‐down approach, we determined the nutrient amounts in the feeds and those in the products (i.e. the liveweight gain, eggs), and the national nutrient excretions were determined as the difference between these amounts. We then calculated the nutrient excretion factors by dividing the national excretions by the number of animals. In the bottom‐up approach, we calculated the amounts of nutrients in the feed and product per head using productivity parameters (feed conversion ratio, etc.). The differences between these amounts were considered the nutrient excretion factors. The average nutrient excretion factors of broilers (g/day/head) estimated using the top‐down and bottom‐up approaches were: N, 1.40 and 1.87; P, 0.36, 0.50; K, 0.54, 0.77; Mg, 0.13, 0.18, respectively. The excretion factors obtained by the top‐down approach can be used to calculate the national/regional excretions. The two approaches resulted in almost the same excretion factors for layers, and the average nutrient excretion factors of layers (g/day/head) estimated were: N, 2.20; P, 0.55; K, 0.68; Mg, 0.23. The estimated excretion factors for N (only) are smaller than the reported factors.     

Phylogenetic analyses of plant-growth-promoting rhizobacteria isolated from tomato,lettuce, and Japanese pepper plants in Hyogo Prefecture,Japan

Approximately 30,000 fluorescent bacterial strains isolated from tomato, lettuce, eggplant, Chinese cabbage, and Japanese pepper plants at seven different locations in Hyogo Prefecture, were screened for plant-growth-promoting (PGP) activity to induce disease resistance against bacterial wilt in tomato. The 37 strains that had higher PGP activity were subjected to molecular phylogenetic analyses using the sequences of the 16S rRNA, gyrB and rpoD genes. Most of the strains were identified as Pseudomonas fluorescens or its close relative, P. putida, while a few strains were grouped with more distantly related bacterial species such as Enterobacter and Stenotrophomonas. The phylogenetic relationships among tomato and lettuce isolates mostly coincided with the source locality and host plants, with a few exceptions. In contrast, isolates from Japanese pepper plants did not form their own cluster but represented several different bacterial species.