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At least 19 recordsLinked to original sources
PubMed1983

Cation exchange--a common mechanism in the storage and release of biogenic amines stored in granules (vesicles)? I. Comparative studies on the uptake of sodium and biogenic amines by the weak cation (carboxyl) exchangers Amberlite IRC-50 and Sephadex C-50 and by biogenic (granule-enriched) materials in vitro.

Studies on the uptake and storage of sodium and biogenic amines (phenylethylamine, noradrenaline, histamine) by two weak cation-exchangers, IRC-50 and Sephadex C-50, and by biogenic granule-enriched preparations demonstrated that the synthetic and biogenic materials had several common characteristics. They showed similar concentration- and pH-dependence and fitted the same cation-exchange and receptor-binding equations. The observations were taken to support the view that the matrices of amine-storing granules have the properties of weak cation-exchangers, with carboxyls as the cation-binding groups.

Animals↗
PubMed1984

Cation exchange--a common mechanism in the storage and release of biogenic amines stored in granules (vesicles)? II. Comparative studies on sodium-induced release of biogenic amines from the synthetic weak cation-exchangers Amberlite IRC-50 and duolite CS-100 and from biogenic (granule-enriched) materials.

Superfusion of phenylethylamine-, noradrenaline- or histamine-charged weak (carboxyl) cation-exchangers (IRC-50 and Duolite CS-100) with isotonic NaCl caused a release of the amines. Similarly, bovine chromaffin granules and nerve granule preparations from bovine splenic nerve, rat vas deferens and rat corpus striatum released their amine(s) upon superfusion with the same solution. The courses of release from the synthetic and biogenic materials showed very similar characteristics and fitted the same exchange equations. The observations support the view that the matrices of the biogenic amine-storing granules have the properties of weak cation-exchanger materials with carboxyls as the cation-binding groups, and that the NaCl-induced release of the biogenic amines is due to cation exchange (Na+ in equilibrium Amine+). The possibility that amine release in vivo is based on cation exchange is discussed.

Adrenergic Fibers↗
PubMed1998

Biogenic amines in silage, apparent postruminal passage, and the relationship between biogenic amines and digestive function and intake by steers.

A 4 x 4 Latin square experiment was conducted to examine abomasal passage of biogenic amines in steers fed silage and their related effects on intake, digestibility, and digestive function. Thirty percent of the dry matter (DM) in the diets consisted of alfalfa forage, which was fed as either hay or silage. The DM from alfalfa silage DM was substituted at 0, 33, 67, and 100% for DM from alfalfa hay and was fed to four ruminally and abomasally cannulated steers. The roughage component of the diet constituted 50% of the DM and consisted of 60% alfalfa silage or hay and 40% tropical corn silage. The concentrate was composed mainly of ground corn. The concentrations of putrescine and cadaverine in abomasal digesta increased as alfalfa silage in the diet increased. Abomasal recovery of biogenic amines, a product of their concentration in abomasal digesta and the passage of DM through the abomasum, was negatively correlated with intake. Abomasal recovery of most amines was 5 to 20% of intake. Abomasal recovery of cadaverine was correlated with depressed intake. Total DM intake was reduced 8.3 to 25.8% as the proportion of alfalfa silage in the diet increased. Frequency of reticular contractions, intake, ruminal DM digestibility, ruminal outflow, volatile fatty acids, and total tract DM digestibility decreased in steers fed diets that contained more alfalfa silage. Ruminal fluid pH and NH3 concentration increased in steers fed more alfalfa silage; however, mass and the DM percentage of ruminal contents decreased linearly. Postprandial insulin concentrations were quadratically related to the proportion of alfalfa hay or silage in the diet. Intraruminal metabolism of biogenic amines is extensive based on the relatively low quantities recovered in abomasal digesta; however, the amounts recovered in abomasal digesta were related to intake depression and associated physiological effects.

Abomasum↗
PubMed2006

Correlation between microbial flora, sensory changes and biogenic amines formation in fresh chicken meat stored aerobically or under modified atmosphere packaging at 4 degrees C: possible role of biogenic amines as spoilage indicators.

This study evaluated the formation of biogenic amines (BAs) in breast chicken meat during storage under aerobic and modified atmospheric packaging (MAP) conditions at 4 degrees C, the correlation of microbial and sensory changes in chicken meat with formation of BAs and the possible role of BAs as indicators of poultry meat spoilage. Poultry breast fillets were stored aerobically or under MAP (30%, CO(2), 70% N(2)) at 4 degrees C for up to 17 days. Quality evaluation was carried out using microbiological, chemical and sensory analyses. Total viable counts, Pseudomonads and Enterobacteriaceae, were in general higher for chicken samples packaged in air whereas lactic acid bacteria (LAB) and Enterobacteriaceae were among the dominant species for samples under MAP. Levels of putrescine and cadaverine increased linearly with storage time and were higher in aerobically stored chicken samples. Spermine and spermidine levels were also detected in both aerobically and MAP stored chicken meat. Levels of tyramine in both chicken samples stored aerobically and or under MAP were low (< 10 mg kg(-1)) whereas the formation of histamine was only observed after day 11 of storage when Enterobacteriaceae had reached a population of ca. 10(7) CFU g(-1). Based on sensory and microbiological analyses and also taking into account a biogenic amines index (BAI, sum of putrescine, cadaverine and tyramine), BAI values between 96 and 101 mg kg(-1) may be proposed as a quality index of MAP and aerobically-packaged fresh chicken meat. Spermine and spermidine decreased steadily throughout the entire storage period of chicken meat under aerobic and MAP packaging, and thus these two amines cannot be used as indicators of fresh chicken meat quality.

Aerobiosis↗
PubMed1993

Biogenic amines in silage. 1. The occurrence of biogenic amines in silage.

In laboratory silages made from orchardgrass, red clover and oats, significant levels of toxic biogenic amines were found. The most widespread were putrescine and cadaverine, concentrations of spermidine, spermine and histamine were ten times lower on average. Of the amines considered, putrescine content seems to be the most sensitive indicator of the extent of putrefaction in silages. A relationship between the putrescine contents and the degree of proteolysis was found. The biogenic amine content is closely connected with both the variety of crop ensiled and even more so with the method and the efficiency of preservation. Neither the application of formic acid nor wilting suppressed the formation of any of the amines in silages selectively. Formic acid suppressed the total concentration of amines to 23% as compared with controls. The highest levels of amines were found in orchardgrass and oat silages; smaller amounts were detected in clover silages. In the case of very poorly preserved silage 100-150 g of toxic amines can be consumed by a cow in a day. This could have a deleterious effect on the physiological condition and the performance of livestock.

Animals↗
PubMed1993

Biogenic amines in silage. 2. The dynamics of the formation of biogenic amines in silage.

When analysing a series of laboratory silages made from orchardgrass, red clover and oats, the fluctuating dynamics of biogenic amines were observed. For levels of putrescine and cadaverine, a rapid exponential increase culminating approximately 30-50 days after ensiling is typical. A small decrease, reaching the minimum at approximately the 100th day, is sometimes followed by a second increase in amine concentrations achieving its maximum approximately 200-230 days after ensiling. Irregular curves of the dynamics probably originate in the simultaneous decarboxylation and deamination reactions along with other relevant amine degradation processes. The dynamics of other biogenic amines-spermidine, spermine and histamine are more difficult to predict. The changes in histamine levels resembled those in the diamines. Some 200 days after ensiling, considerable increases in this toxic amine were observed. The dynamics of some quality criteria, especially the degree of proteolysis, were in many cases similar to those of the amines.

Animals↗
PubMed1993

Biogenic amines in silage. 3. The occurrence of six biogenic amines in farm-scale grass and maize silages.

Concentrations of putrescine (PUT), cadaverine (CAD), spermidine (SPD), spermine (SPM), histamine (HIS) and tyramine (TYR) in 53 grass silages and 54 maize silages were determined using an HPLC method. Concentrations of all amines excluding SPD in grass silages decreased significantly with increasing dry matter (DM) contents and decreasing acetic acid concentrations. The mean concentrations were 1310, 642, 414, 139, 120 and 33.6 mg/kg for TYR, CAD, PUT, SPM, HIS and SPD respectively in grass silages of 20-30% DM. The maximal values found were twice to five times higher than the mean values. The effect of increasing DM on the amines concentrations was not evident in maize silages. The mean concentrations, regardless of the DM content, were surprisingly high: 435, 388, 341, 71.7, 25.1 and 5.4 mg/kg for TYR, PUT, CAD, HIS, SPD and SPM. The maximal values in maize silages were three times to ten times higher than the mean values. Considering that maize silage forms the great proportion of the diets of cattle during long-term winter feeding, further toxicological and physiological research should be carried out.

Animals↗
PubMed2006

Biogenic emissions of isoprenoids and NO in China and comparison to anthropogenic emissions.

In this study, a regional dynamical model (WRF) is used to drive biogenic emission models to calculate high resolution (10x10 km) biogenic emissions of isoprene (C(5)H(8)), monoterpenes (C(10)H(16)), and nitric oxide (NO) in China. This high resolution biogenic inventory will be available for the community to study the effect of biogenic emissions on photochemical oxidants in China. The biogenic emissions are compared to anthropogenic emissions to gain insight on the potential impact of the biogenic emissions on tropospheric chemistry, especially ozone production in this region. The results show that the biogenic emissions in China exhibit strongly diurnal, seasonal, and spatial variations. The isoprenoid (including both isoprene and monoterpenes) emissions are closely correlated to tree density and strongly vary with season and local time. During winter (January), the biogenic isoprenoid emissions are the lowest, resulting from lower temperature and solar radiation, and highest in summer (July) due to higher temperature and solar radiation. The biogenic NO emissions are also higher during summer and lower during winter, but the magnitude of the seasonal variation is smaller than the emissions of isoprene and monoterpenes. The biogenic emissions of NO are widely spread out in the northern, eastern, and southern China regions, where high-density agricultural soil lands are located. Both biogenic NO and isoprenoid emissions are very small in western China. The calculated total biogenic emission budget is smaller than the total anthropogenic VOC emission budget in China. The biogenic isoprenoid and anthropogenic VOC emissions are 10.9 and 15.1 Tg year(-1), respectively. The total biogenic and anthropogenic emissions of NO are 5.9 and 11.5 Tg(NO) year(-1), respectively. The study shows that in central eastern China, the estimated biogenic emissions of isoprenoids are very small, and the anthropogenic emissions of VOCs are dominant in this region. However, in northeastern and southern China, there are relatively large biogenic emissions of isoprenoids, leading to an important impact on the ozone production in these regions. Furthermore, the emissions of isoprenoids are highest during summer and noontime, which correlates to the peak of ozone production period. For example, the ratio between summer and winter for the emissions of isoprenoids is about 15 in China. As a result, the biogenic emissions of isoprenoids are significantly larger than the anthropogenic emissions of VOCs in China during daytime in summer. Biogenic NO emissions are mostly produced by agricultural soils which co-exist with large populations and human activity. As a result, the biogenic emissions of NO are mostly overlapped with the anthropogenic emissions of NO, leading to the enhancement in NO concentrations in the high anthropogenic NO emission regions. Finally, the future emissions of isoprene and monoterpenes over China are estimated. The results show that the future biogenic emissions may increase significantly due to land cover changes in central eastern China, which could have a very important impact on ozone formation in this region. However, these estimates are highly uncertain and are presented as a potential scenario to show the importance of possible changes of biogenic emissions in China.

Air Pollutants↗
PubMed2002

Contribution of biogenic emissions to the formation of ozone and particulate matter in the eastern United States.

As anthropogenic emissions of ozone (O3) precursors, fine particulate matter (PM2.5), and PM2.5 precursors continue to decrease in the United States, the fraction of O3 and PM2.5 attributable to natural sources may become significant in some locations, reducing the efficacy that can be expected from future controls of anthropogenic sources. Modeling studies were conducted to estimate the contribution of biogenic emissions to the formation of O3 and PM2.5 in Nashville/TN and the northeastern United States. Two approaches were used to bound the estimates. In an anthropogenic simulation, biogenic emissions and their influence at the domain boundaries were eliminated. Contributions of biogenic compounds to the simulated concentrations of O3 and PM2.5 were determined by the deviation of the concentrations in the anthropogenic case from those in the base case. A biogenic simulation was used to assess the amounts of O3 and PM2.5 produced in an environment free from anthropogenic influences in emissions and boundary conditions. In both locations, the contribution of biogenic emissions to O3 was small (<23%) on a domain-wide basis, despite significant biogenic volatile organic compounds (VOC) emissions (65-89% of total VOC emissions). However, the production of O3 was much more sensitive to biogenic emissions in urban areas (22-34%). Therefore, the effects of biogenic emissions on O3 manifested mostly via their interaction with anthropogenic emissions of NOx. In the anthropogenic simulations, the average contribution of biogenic and natural sources to PM2.5 was estimated at 9% in Nashville/TN and 12% in the northeast domain. Because of the long atmospheric lifetimes of PM2.5, the contribution of biogenic/natural PM2.5 from the boundary conditions was higher than the contribution of biogenic aerosols produced within the domain. The elimination of biogenic emissions also affected the chemistry of other secondary PM2.5 components. Very little PM2.5 was formed in the biogenic simulations.

Air Pollutants↗
PubMed2000

Modeling and direct sensitivity analysis of biogenic emissions impacts on regional ozone formation in the Mexico-U.S. border area.

A spatially and temporally resolved biogenic hydrocarbon and nitrogen oxides (NOx) emissions inventory has been developed for a region along the Mexico-U.S. border area. Average daily biogenic non-methane organic gases (NMOG) emissions for the 1700 x 1000 km2 domain were estimated at 23,800 metric tons/day (62% from Mexico and 38% from the United States), and biogenic NOx was estimated at 1230 metric tons/day (54% from Mexico and 46% from the United States) for the July 18-20, 1993, ozone episode. The biogenic NMOG represented 74% of the total NMOG emissions, and biogenic NOx was 14% of the total NOx. The CIT photochemical airshed model was used to assess how biogenic emissions impact air quality. Predicted ground-level ozone increased by 5-10 ppb in most rural areas, 10-20 ppb near urban centers, and 20-30 ppb immediately downwind of the urban centers compared to simulations in which only anthropogenic emissions were used. A sensitivity analysis of predicted ozone concentration to emissions was performed using the decoupled direct method for three dimensional air quality models (DDM-3D). The highest positive sensitivity of ground-level ozone concentration to biogenic volatile organic compound (VOC) emissions (i.e., increasing biogenic VOC emissions results in increasing ozone concentrations) was predicted to be in locations with high NOx levels, (i.e., the urban areas). One urban center--Houston--was predicted to have a slight negative sensitivity to biogenic NO emissions (i.e., increasing biogenic NO emissions results in decreasing local ozone concentrations). The highest sensitivities of ozone concentrations to on-road mobile source VOC emissions, all positive, were mainly in the urban areas. The highest sensitivities of ozone concentrations to on-road mobile source NOx emissions were predicted in both urban (either positive or negative sensitivities) and rural (positive sensitivities) locations.

Agriculture↗
PubMed2005

Estimation of biogenic emissions with satellite-derived land use and land cover data for air quality modeling of Houston-Galveston ozone nonattainment area.

The Houston-Galveston Area (HGA) is one of the most severe ozone non-attainment regions in the US. To study the effectiveness of controlling anthropogenic emissions to mitigate regional ozone nonattainment problems, it is necessary to utilize adequate datasets describing the environmental conditions that influence the photochemical reactivity of the ambient atmosphere. Compared to the anthropogenic emissions from point and mobile sources, there are large uncertainties in the locations and amounts of biogenic emissions. For regional air quality modeling applications, biogenic emissions are not directly measured but are usually estimated with meteorological data such as photo-synthetically active solar radiation, surface temperature, land type, and vegetation database. In this paper, we characterize these meteorological input parameters and two different land use land cover datasets available for HGA: the conventional biogenic vegetation/land use data and satellite-derived high-resolution land cover data. We describe the procedures used for the estimation of biogenic emissions with the satellite derived land cover data and leaf mass density information. Air quality model simulations were performed using both the original and the new biogenic emissions estimates. The results showed that there were considerable uncertainties in biogenic emissions inputs. Subsequently, ozone predictions were affected up to 10 ppb, but the magnitudes and locations of peak ozone varied each day depending on the upwind or downwind positions of the biogenic emission sources relative to the anthropogenic NOx and VOC sources. Although the assessment had limitations such as heterogeneity in the spatial resolutions, the study highlighted the significance of biogenic emissions uncertainty on air quality predictions. However, the study did not allow extrapolation of the directional changes in air quality corresponding to the changes in LULC because the two datasets were based on vastly different LULC category definitions and uncertainties in the vegetation distributions.

Air Pollution↗