The phenolic composition of pine bark from a variety of Pinus species was estimated by measuring Klason lignin, acid-soluble lignin, and a 1% NaOH extract. Polyphenol contents of hot
water extracts from pine bark were determined by the Folin-Ciocalteu assay and the vanillin-H2SO4 assay. Among the pine bark varieties investigated, Pinus radiata bark showed the highest polyphenol content and potent antioxidant activity. Pinus rigida bark was also a usable polyphenol-rich source, whereas Pinus densiflora bark had a low yield (5.1%) of hot water extract, although it showed potent antioxidant activity. Correlations between proanthocyanidin
content in pine bark and antioxidant activity were observed. The results suggested that proanthocyanidin was the crucial contributor
to potent antioxidant activity in pine bark.
The publication of this article was made possible by an Emachu Research Fund. The authors are grateful for the fund. 相似文献
Lack of data especially pertaining to the chemistry of mangrove wood species makes it difficult to prepare successful plans
for their conservation and to use mangroves as a source of wood fiber. In this paper, chemical characterizations of the six
main mangrove species of Bangladesh [namely Keora (Sonneratia apetala), Geoa (Excoecaria agallocha), Bine (Avicennia alba), Sundari (Heritiera fomes) Pashur (Xyloccarpous mekongests), and Kakra (Bruguiera gymnorhiza)] were investigated. The chemical results revealed that these species contain high percentages of dichloromethane followed
by methanol extractives. Methanol extracts in Pashur, Sundari, and Bine were higher than 10%, which indicates high percentage
of tannin material. The total lignin content in these species was higher than 25%, except for Gewa (23.6%) and Pashur (21.3%),
which is higher than that of the normal range of hardwood. The pentosan content in these six species was within the range
of 19.4–22.8%. The α-cellulose content in Keora and Gewa was acceptable for pulp production, but the others were lower than
the normal range of hardwood. Alkaline nitrobenzene oxidation showed that all these species had a very high syringaldehyde
to vanillin (2.6–5.0) ratio except Keora (1.6). Surprisingly, rhamnose is the main constituent with xylose of hemicelluloses
of these six mangrove species. The ash content in these six mangrove wood species was also higher than that in normal hardwood. 相似文献
A continuous CO2 measurement system was developed to monitor the CO2 exchange rate of the whole canopy of grafted transplants using semi-open multiple chambers. Air heating or cooling and humidification inside a healing box were under control, if needed. To test the system, the gas exchange rate of the cucumber (Cucumis sativus L.) transplants grafted onto pumpkin (Cucurbita maxima cv. ‘New-Shintozwa’) was analysed. During the healing and acclimatisation of the grafted cucumber plants, the air temperature in the box remained constant at night but ranged above 1 °C of a set value under high humidity in daytime. The relative humidity was kept within the set point during the daytime, and it nearly reached 100% at night when not controlled. The cucumber seedlings were exposed to different water stresses before grafting, and the water potentials of each treatment were −0.579 (non-stressed), −0.814 (mildly water-stressed), and −0.870 MPa (strongly water-stressed) on grafting. At the water-stressed scions, leaf expansion was inhibited by 30.9–53.3% compared with the non-stressed scions. Therefore, the gas exchange rates of the strongly water-stressed scions based on the leaf area were decreased to 72.7% compared with the non-stressed scions. After grafting, the apparent photosynthesis of the transplants of all treatments was negative, with higher respiration in the strongly water-stressed scions during the initial period of healing. However, they turned to positive values and exceeded those of the non-stressed scions from three days after grafting. This result provides critical information that the water column is physiologically connected between the stock and scion within two days after grafting. As a result of water stress, the leaf area and dry weight of the transplants in the strongly water-stressed scions were inhibited by 67.5% and 83% compared with the non-stressed scions at the end of acclimatisation. In contrast, the relative growth rate and graft-take of the strongly water-stressed transplants were slightly increased, which suggests that the water stress prior to grafting alleviated the water demand of the scion. This system may provide useful information for diagnosis at the early stage by monitoring the whole canopy's photosynthesis over a long term. 相似文献
The slow rate of the oxygen reduction reaction (ORR) in the polymer electrolyte membrane fuel cell (PEMFC) is the main limitation for automotive applications. We demonstrated that the Pt3Ni(111) surface is 10-fold more active for the ORR than the corresponding Pt(111) surface and 90-fold more active than the current state-of-the-art Pt/C catalysts for PEMFC. The Pt3Ni(111) surface has an unusual electronic structure (d-band center position) and arrangement of surface atoms in the near-surface region. Under operating conditions relevant to fuel cells, its near-surface layer exhibits a highly structured compositional oscillation in the outermost and third layers, which are Pt-rich, and in the second atomic layer, which is Ni-rich. The weak interaction between the Pt surface atoms and nonreactive oxygenated species increases the number of active sites for O2 adsorption. 相似文献
Dill (Anethum graveolens L.) leaf, seed and their essential oil are rich source of antioxidants. The plant is native in Southwest Asia and is cultivated in Europe, India and the United States. This study evaluated the genetic diversity structure of 135 accessions of A. graveolens from different continents, based on random amplified polymorphic DNA (RAPD) markers. The selected 10 RAPD primers generated a total of 142 highly reproducible bands, among which 89 were polymorphic. Percentage of polymorphism varied from 41.17 % (OPB20) to 92.85 % (OPB15) with an average of 77.74 %. A relatively high genetic diversity was detected among all the accessions with the Nei’s genetic diversity (H) values ranged from 0.346 (OPB07) to 0.444 (OPB18) with a mean of 0.401. When estimated for Shannon’s information index (I), it has ranged from 0.530 (OPB12) to 0.652 (OPB18), the mean was observed as 0.581. The respective values of H and I were found to be the highest value for primer OPB18. Cluster analysis of RAPD data using UPGMA algorithm based on Nei’s genetic similarity matrix placed the 135 accessions into two main clusters. Although a number of groups can be identified, the clusters show little to no association with the geographic origin of the material. The implication of the results of this study in developing a strategy for the conservation and breeding of dill germplasm are discussed. 相似文献
1. The present study was conducted to develop Citrus junos probiotics (CJP), using by-products of Citrus junos fermented with multispecies probiotic bacteria including Saccharomyces cerevisiae, Enterococcus faecium, Lactobacillus acidophilus and Bacillus subtilis. The effects of dietary CJP on the growth performance, immune status, caecal microbiology and meat oxidative stability of broiler were investigated.
2. A total of 240 one-day-old Ross broiler chicks were used in a 35-d experiment in which the chicks were randomly allotted to one of the 4 dietary treatments (0, 5, 10 and 20 g CJP/kg diet) in a completely randomised design.
3. Dietary supplementation of 5 g/kg CJP significantly increased body weight, average daily gain and average daily feed intake of broiler during the overall experimental period.
4. Serum immunoglobulin (Ig)M concentration was significantly increased by 10 and 20 g/kg CJP, whereas the IgG and IgA concentration remained unaffected. In addition, 20 g/kg CJP significantly inhibited proliferation of Escherichia coli without affecting the concentration of Lactobacillus or Bacillus spp.
5. A significant reduction in the thiobarbituric acid reactive substances values of breast and thigh meat was observed in response to increasing concentration of dietary CJP.
6. Thus, the results suggest that CJP up to a concentration of 20 g/kg can be used in the diet of broilers to improve immunity and to reduce caecal E. coli and TBARS values of breast and thigh meat without any adverse effects on growth performance. 相似文献
1. Corni fructus is the fruit of Cornus officinalis, a dogwood species. This study was conducted to prepare fermented corni fructus preparation (FCFP) and fermented kelp (FK) from corni fructus and by-products of Laminaria japonica fermented with Bacillus subtilis and Aspergillus oryzae.
2. The effects of dietary FCFP and FK as replacer of oxytetracycline (OTC) on growth performance, meat composition, meat oxidative stability, and emissions of ammonia (NH3) and hydrogen sulphide (H2S) from broiler chicken droppings were investigated.
3. A total of 140 d-old broiler chicks were randomly allotted to 4 dietary treatments including control, OTC (0.05 g/kg), FCFP (5 g/kg), and FK (5 g/kg).
4. Overall, inclusion of FCFP resulted in lower weight gain and feed intake during the overall experimental period. Broilers fed FCFP diets tended to have lower crude fat and higher crude ash content in the carcasses.
5. In the fresh state, the malondialdehyde (MDA) value of broiler meat was lower in the FK supplemented group. At one week, meat from broilers fed antibiotic and FK diets had lower MDA values, whereas at 2 weeks broiler meat from all dietary treatment groups had lower MDA values than the control.
6. Dietary supplementation with FK significantly reduced faecal NH3 emissions throughout the experimental period, whereas dietary OTC and FCFP supplementation increased NH3 emissions at 2 and 4 weeks. There were no significant effects of dietary treatments on H2S emissions throughout the experimental period, except during week one, when FCFP supplementation reduced the emission.
7. In conclusion, dietary supplementation with 5 g/kg FK improved the oxidative stability of broiler meat and reduce faecal NH3 emissions without affecting growth performance. 相似文献
Dietary substitution effect of sea tangle (ST) with rice bran (RB) on growth and carcass composition of juvenile abalone (Haliotis discus) was determined. Juvenile abalone was acclimated to the experimental conditions for 4 weeks. Seventy juvenile abalone averaging 0.43 g were randomly distributed into each of the 18, 70 L plastic rectangular containers. The experimental diets were fed to abalone once a day at a satiation level with a little leftover. The feeding trial lasted for 16 weeks. Survival of abalone was not affected by dietary substitution of ST with RB. However, weight gain of abalone fed the RB40 diet was higher than that of abalone fed the all other diets except for the RB0 diet. No significant difference in weight gain was found in abalone fed between the RB0 and RB100 diets. SGR of abalone fed the RB40 diet was higher than that of abalone fed the all other diets. Also SGR of abalone fed the RB0 diet was higher than that of abalone fed the RB100 diet, but not different from that of abalone fed the RB20, RB60 and RB80 diets. Moisture, crude protein and ash content of the soft body of abalone were affected by dietary substitution of ST with RB. In conclusion, the 100% ST could be substituted with RB without a retardation of weight gain of abalone when the 20% ST was included into the experimental diet. However, the best growth performance was obtained in abalone fed the RB40 diet substituting 40% ST with RB. 相似文献
Constituents of tars formed during the aging of bamboo (Phyllostachys pubescens), oak (Quercus serrata), and pine (Pinus densiflora) wood crude vinegars were analyzed by pyrolysis-gas chromatography (Py-GC) and pyrolysis-gas chromatography-mass spectrometry
(Py-GC-MS) to investigate their origination. The pyrolysate of tars obtained from the wood and bamboo crude vinegars were
almost identical and were primarily composed of phenolic compounds and aromatic hydrocarbons. In addition, during the aging
of model wood vinegar that was prepared for comparison with the wood and bamboo vinegars, a marked decrease was observed in
the levels of phenolic compounds (phenol; o-, p-, and m-cresol; and syringol). Furthermore, the Py-GC-MS results of the tars produced during the aging of the model wood vinegar
revealed that phenolic compounds were primarily responsible for the formation of tar during the aging of wood and bamboo crude
vinegars. Pyrroles, which may be derived from the primary pyrolysate of amino acids, nitrogen-containing extracts, or both,
were also partially involved in the formation of tar during the aging period. 相似文献
Pathological characteristics of olive flounder Paralichthys olivaceus experimentally infected with Streptococcus parauberis were studied. Various stressful conditions, aeration and netting stress in particular, led to induced mortality by S. parauberis. Netting stress-induced mortality was positively correlated to bacterial dose and stressful conditions. Inflammation of the
heart and pericarditis was the major pathological change observed in olive flounder experimentally infected with S. parauberis. During the infected period, the number of bacteria in the infected olive flounder was recorded over time. S. parauberis remained in all fish organs tested, especially in the heart and brain. 相似文献