Phenolic antioxidants from the heartwood of Acacia confusa     

Wu JH  Tung YT  Wang SY  Shyur LF  Kuo YH  Chang ST 《Journal of agricultural and food chemistry》2005,53(15):5917-5921

In the present study, the ethanolic extracts from the heartwood of Acacia confusa, a species indigenous to Taiwan, exhibit strong antioxidant effects. Among all the fractions from ethanolic extracts of heartwood, the EtOAc soluble fraction exhibits the best antioxidant activity. The 80% 1,1-diphenyl-2-picrylhydrazyl radical inhibitory activity by the EtOAc extract was observed at a concentration of 5 mug/mL, and at the same dosage there was a similar free radical scavenging activity for (-)-ascorbic acid and (+)-catechin, both of which are well-known antioxidants. In addition, the EtOAc extract also protects PhiX174 supercoiled DNA against strand scission induced by hydroxyl radical. Furthermore, following by column chromatography and reverse-phase high-performance liquid chromatorgrapy, 10 pure phenolic compounds, including three major antioxidants (3,7,8,3',4'-pentahydroxyflavone, 7,8,3',4'-tetrahydroxy-3-methoxyflavone, and 3,4,2',3',4'-pentahydroxy-trans-chalcone) and a new flavonoid (3,7,8,3'-tetrahydroxy-4'-methoxyflavone), were isolated from the ethanolic extracts of A. confusa heartwood.  相似文献   

Effect of environmental calcium levels on calcium uptake in tilapia larvae Oreochromis mossambicus     

Pr. Pung-Pung Hwang  Yu-Chi Tung  Min-Hwang Chang 《Fish physiology and biochemistry》1996,15(5):363-370

Effects of environmental calcium concentrations on the survival, growth, body calcium content and calcium uptake kinetics in developing tilapia (Oreochromis mossambicus) larvae were studied. Fertilized eggs were incubated in high- and low-calcium artificial freshwater (0.88–0.96 mmol l^–1 vs. 0.02–0.03 mmol l^–1 CaCl₂ or CaSO₄) until 3 days after hatching. Tilapia larvae showed similar hatching rates and wet weights in either high- or low-calcium medium, indicating neither the development nor the growth in tilapia larvae was affected by the environmental calcium levels. The body calcium content in low-calcium groups was about 90–95% that of high-calcium groups, No matter what calcium source was used (CaCl₂ or CaSO₄), acclimation to low calcium medium caused a stimulation of calcium uptake (measured in 0.2 mmol l^–1 calcium),i.e., 1.2–1.3 fold higher than that of high calcium groups. This enhanced calcium uptake capacity was characterized by a 50% decrease in K_m and a 25% increase in J_max. Effect of different calcium salts on calcium influx was significant only in low calcium level,i.e., calcium influx in low-CaCl₂ group higher than that in low-CaSO₄ group. These results suggest that tilapia larvae are able to modulate their calcium uptake mechanism to maintain normal body calcium content and growth in environments with different levels of calcium.  相似文献   

Serological survey for antibodies to Encephalitozoon cuniculi in rabbits in Taiwan     

Tee KY  Kao JP  Chiu HY  Chang MH  Wang JH  Tung KC  Cheng FP  Wu JT 《Veterinary parasitology》2011,183(1-2):68-71

Encephalitozoon cuniculi (E. cuniculi) is a microsporidian parasite commonly found in rabbits that can infect humans, causing encephalitozoonosis. Our laboratory recently confirmed the first case of encephalitozoonosis in a rabbit in Taiwan; the prevalence of encephalitozoonosis is not well documented, even when many clinics suspect pet rabbits as being infected. This study surveys the seropositivity of E. cuniculi using carbon immunoassay (CIA) and enzyme-linked immunosorbent assay (ELISA). Serological examination of 171 rabbits using CIA and ELISA showed that 63.2% (108/171) and 67.8% (116/171) were seropositive against E. cuniculi, respectively. Thirteen of the 14 rabbits (92.9%) with neurological symptoms were seropositive. Except for gender, health status and location had a significant effect on E. cuniculi seropositivity (p<0.05). Adult rabbits aged older than 4 months exhibited significantly higher seropositivity for E. cuniculi than young rabbits (p<0.05). In conclusion, this study shows that E. cuniculi is present and widespread among healthy rabbits in Taiwan. Therefore, the fields of veterinary and human medicine in Taiwan should be aware of this zoonotic issue and the resulting public health concern of encephalitozoonosis.  相似文献   

Development of an in-field cattle finishing system for the tropics     

Devindar Singh  Harris M. Gitlin  J. R. Carpenter  Tung Liang 《Agricultural Systems》1986,20(4):281-299

An in-field cattle finishing system that takes advantage of the year long growing season in the tropics is described. This system exploits the interrelationships of the feed production and cattle feeding components to increase the cost and energy efficiency of the system in tropical environments. The system is based on regulated feeding of mature zones of standing corn crop to cattle. The corn crop is planted at weekly intervals year round in continual rotation. When the first planting gets to the dough-dent stage of maturity, cattle are put in the cornfield within a movable cattle pen. The feeding is regulated by moving the pen a fixed distance twice a day. This system may reduce the cost of fattening an animal from 250 to 475 kg by about 26%. To test the practicality and engineering feasibility of this program, an exploratory experiment was conducted using three steers, a 6 m × 6 m movable cattle pen and 0·23 ha land area.

It was observed that the trampling loss of corn ears by the cattle was minimal after the initial learning period of 2 to 3 weeks. The cattle also utilized about 50% to 80% of the leaves and 20% to 65% of the cornstalks. The uneaten stalks provided an excellent bedding material during wet periods. The animal weight gain performance was similar to that of feedlot cattle of the same age, weight and breed. No major health or disease problem was observed. The performance of the movable cattle pen was satisfactory during normal weather periods, but a more positive locomotion system is needed for wet conditions.  相似文献   

Simulation-aided development of the Hawaii swine research programme     

Devindar Singh  Williams I. Hugh  Tung Liang 《Agricultural Systems》1980,5(4):279-294

A computer model is presented to estimate the quantitative impact of future research/extension activities in various aspects of swine production on the profit of an average swine producer in Hawaii. The model was designed and used to generate information for making decisions regarding funding of future research/extension projects in the swine production area. The computer model has two components. The first simulates the biological production behaviour of a typical pig enterprise of Hawaii. The General Purpose Simulation System (GPSS) language was used to model the stochastic nature of the production. For a given set of biological parameters, this component provides annual production levels, feed consumption and statistics for selecting the capacity of various building facilities. The second component computes annual revenues, costs and rate of return to capital investment over the analysis period by using discounted cash flow method. In addition to other cost and price data, it uses the output of the first component as input.  相似文献   

Actin Polymerization: An Event Regulated by Tyrosine Phosphorylation During Buffalo Sperm Capacitation          下载免费PDF全文

S Naresh  SK Atreja 《Reproduction in domestic animals》2015,50(6):1047-1053

In the female reproductive tract, the spermatozoa undergo a series of physiological and biochemical changes, prior to gaining the ability to fertilize, that result to capacitation. However, the actin polymerization and protein tyrosine phosphorylation are the two necessary steps for capacitation. In this study, we have demonstrated the actin polymerization and established the correlation between protein tyrosine phosphorylation and actin reorganization during in vitro capacitation in buffalo (Bubalus bubalis) spermatozoa. Indirect immunofluorescence and Western blot techniques were used to detect actin polymerization and tyrosine phosphorylation. The time‐dependent fluorimetric studies revealed that the actin polymerization starts from the tail region and progressed towards the head region of spermatozoa during capacitation. The lysophosphatidyl choline (LPC)‐induced acrosome reaction (AR) stimulated quick actin depolymerization. The inhibitor cytochalasin D (CD) blocked the in vitro capacitation by inhibiting the actin polymerization. In addition, we also performed different inhibitor (Genistein, H‐89, PD9809 and GF‐109) and enhancer (dbcAMP, H₂O₂ and vanadate) studies on actin tyrosine phosphorylation and actin polymerization. The inhibitors of tyrosine phosphorylation inhibit actin tyrosine phosphorylation and polymerization, whereas enhancers of tyrosine phosphorylation stimulate F‐actin formation and tyrosine phosphorylation. These observations suggest that the tyrosine phosphorylation regulates the actin polymerization, and both are coupled processes during capacitation of buffalo spermatozoa.  相似文献   

Effects of heat tolerance on expression of resistance toPresudomonas solanacearum E. F. Smith in potato     

Pham X. Tung  John G. Th. Hermsen  Peter Vander Zaag  Peter Schmiediche 《Potato Research》1992,35(3):321-328

Summary Twelve potato clones with different genetic background for resistance to bacterial wilt and adaptation were tested for resistance to a race 1 and a race 3 isolate of the pathogen at three locations in the Philippines representing different ranges of ambient temperature. The results showed that the genes for heat tolerance are crucial for resistance. Stability analysis indicated that clones with both resistance and heat tolerance genes displayed higher and more stable resistance to the race 1 isolate than those clones having only resistance genes. The latter group tended to have higher values of both regression of disease index on environmental index and deviation from the regression in the stability analysis. Host — pathogen interaction effects were found to be statistically significant but small compared to main effects of isolates and clones. The involvement of genes with different effects on wilt resistance is discussed. Introduction  相似文献   

Preparation and application of an<Emphasis Type="Italic">s</Emphasis>-triazine-based novel<Emphasis Type="Italic">N</Emphasis>-halamine biocide for antimicrobial fibers     

Jaewoong Lee  Royall M. Broughton  Akin Akdag  S. D. Worley  Tung S. Huang 《Fibers and Polymers》2007,8(2):148-154

N-halamines serve as important antimicrobial agents. Development of this class of compounds has been shown to provide benefits especially from a biocidal point of view. A novels-triazine-basedN-heterocycle, dichloro-m-aminophenyl-hydantoinyl-s-triazine (DAPHT), which could be rendered antimicrobial through exposure to diluted chlorine bleach, was synthesized and characterized by¹H NMR,¹³C NMR, and FT-IR. A finishing method was used to apply theN-halamine precursor onto cotton fabric, and the optimum conditions for finishing were investigated. The DAPHT-treated cotton fabric had durable antimicrobial properties up to 50 standard washing cycles and was rechargeable under normal laundry/bleaching conditions. The antimicrobial efficacy against Gram-positive and Gram-negative bacteria was demonstrated.  相似文献   

Role of crop diversification and integrated nutrient management in resilience of soil fertility under rice-wheat cropping system     

SN Sharma  SK Sharma 《Archives of Agronomy and Soil Science》2013,59(3):345-352

A field study conducted for two crop cycles of five cropping systems supplied with six nutrient combinations at the Indian Agricultural Research Institute, New Delhi indicated that the cropping systems having a legume increased organic C content over initial level by 0.02?–?0.05%, available N by 3.5?–?14.1?kg ha^???1, whereas the rice-wheat cropping system resulted in a reduction in organic C and available N over initial level by 0.05% and 1.5?kg ha^???1, respectively after 2 years of study. Rice-potato-mungbean cropping system resulted in a negative balance of available P and rice-clover cropping system had a negative balance of both available P and available K content in soil and thus call for adequate P and K fertilization. Application of P and K helped in building up their content in soil; NPK?+?FYM showed the highest increase in organic C, available N, available P and available K content in soil. These results suggest the inclusion of a legume in a cropping system for maintaining organic C and available N in soil and adequate P and K fertilization for arresting the depletion of available P and K content in soil. Integrated nutrient management is one of the best methods for resilience of soil fertility under rice-wheat cropping system.  相似文献   

Cryopreservation of Zona‐Free Cloned Buffalo (Bubalus Bubalis) Embryos: Slow Freezing vs Open‐Pulled Straw Vitrification     

K Sirisha  NL Selokar  M Saini  P Palta  RS Manik  MS Chauhan  SK Singla 《Reproduction in domestic animals》2013,48(4):538-544

This study was carried out to compare the post‐thaw cryosurvival rate and the level of apoptosis in vitro produced zona‐free cloned buffalo blastocysts subjected to slow freezing or vitrification in open‐pulled straws (OPS). Zona‐free cloned embryos produced by handmade cloning were divided into two groups and were cryopreserved either by slow freezing or by vitrification in OPS. Cryosurvival of blastocysts was determined by their re‐expansion rate following post‐thaw culture for 22–24 h. The post‐thaw re‐expansion rate was significantly (p < 0.05) higher following vitrification in OPS (71.2 ± 2.3%) compared with that after slow freezing (41.6 ± 4.8%). For examining embryo quality, the level of apoptosis in day 8 frozen‐thawed blastocysts was determined by TUNEL staining. The total cell number was not significantly different among the control non‐cryopreserved cloned embryos (422.6 ± 67.8) and those cryopreserved by slow freezing (376.4 ± 29.3) or vitrification in OPS (422.8 ± 36.2). However, the apoptotic index, which was similar for embryos subjected to slow freezing (14.8 ± 2.0) or OPS vitrification (13.3 ± 1.8), was significantly (p < 0.05) higher than that for the control non‐cryopreserved cloned embryos (3.4 ± 0.6). In conclusion, the results of this study demonstrate that vitrification in OPS is better than slow freezing for the cryopreservation of zona‐free cloned buffalo blastocysts because it offers a much higher cryosurvival rate.  相似文献