Average Relative Content Research Articles

Chemotaxonomic variation of volatile components in Zanthoxylum Bungeanum peel and effects of climate on volatile components

BackgroundZanthoxylum bungeanum Maxim. is widely distributed across China, and the aroma of its peel is primarily determined by its volatile components. In this study, we analyzed the characteristics of volatile components in Z. bungeanum peels from different regions and investigated their correlation with climatic factors.ResultsThe results identified 126 compounds in Z. bungeanum, with 27 compounds exhibiting distinct odor characteristics. Linalool was the most abundant, with an average relative content of 21.664%. The volatile oil of Z. bungeanum predominantly features spicy, floral, citrus, and mint aromas. The classification results indicated a significant difference in elevation at the ZB10 collection points in Shaanxi Province compared to other groups. Temperature, average annual precipitation, and wind speed were crucial factors influencing the accumulation of volatile components.ConclusionsThis study is beneficial for enhancing the quality of Z. bungeanum, expanding the understanding of how climatic factors influence the accumulation of volatile substances, and promoting agricultural practices in regions with similar climatic conditions.

Effect of Microbial Community on Iron Release under Low Velocity in Drinking Water Supply Pipes

Iron release from water supply network affects water quality safety. To investigate the change of microbial community structure and its effect on iron release in water supply pipes under leakage condition, the research was carried out based on the pilot platform used in actual water supply system. Microbial community structure was analyzed using high-throughput sequencing and the total iron index was measured by atomic flame absorption spectroscopy. The results showed that Proteobacteria had a large competitive advantage in the laminar flow rate, the average relative content increased more than 60%. At the level of class, the relative content of Alphaproteobacteria, Gammaproteobacteria, Betaproteobacteria increased larger than others. When the velocity was close to the critical flow rate, the microbial community was gradually stabilized. The total iron concentration decreased with the increase of flow rates, when the flow rate was 40% of the critical flow rate, the total iron concentration tended to be stable, and the promotion of total iron release was mainly iron-oxidizing bacteria and sulfate reducing bacteria, and the inhibition effect was mainly nitrate reducing bacteria. It has important reference significance for further controlling the microbial community and iron release in the water at the end of the pipe network.

Leaf Volatiles and Relevant Gene Expression as the Specific Characteristics in Citrus depressa Accession Discrimination

Citrus depressa Hayata is the native and widespread citrus species in Taiwan. The notable character is that C. depressa has a distinct aroma different from local citrus. The ex situ germplasm of scions from different collection regions has variant leaf shapes and different odor characteristics. Establishing volatile biomarkers for classifying the local C. depressa is beneficial to commercial development. Volatile organic compounds (VOCs) of fresh leaves from seven C. depressa accessions which were collected from different locations in Taiwan were extracted by headspace solid-phase microextraction and analyzed by GC-MS. The volatile compositions from each season showed the diversity, and linalool, of which the average relative content is 52.7%, was the most volatile component in any season. The other main VOCs of leaves of C. depressa were γ-terpinene, limonene, β-ocimene, and α-terpineol. The result of linear discriminant analysis by VOC markers shows that there are two main different types which are (1) accessions from the central and the east of Taiwan and (2) accessions which are closer to C. depressa in Okinawa, Japan. Five major VOC-related synthase genes were selected and the gene expression was used to classify the varieties. The clustering result is the same with VOC-based discrimination. Our results reveal leaf volatile profiling is capable of being the discrimination markers, and the possibility for constructing molecular markers is directly related to characteristics from secondary metabolites phenotyping.

Characteristics of microorganisms and origin of organic matter in Wufeng Formation and Longmaxi Formation in Sichuan Basin, South China

Abstract To evaluate the characteristics of microorganisms and the origin of organic matter of the Wufeng Formation and Longmaxi Formation (WF-LMX) in Sichuan Basin (South China), the type and number of microorganisms were determined in this study using scanning electron microscope (SEM) microphotographs and microbial extraction. The contribution of various microorganisms to organic matter was analyzed in combination with the data of biomarkers and total organic carbon (TOC). It can be deduced from the paleogeography and pristine/phytane (Pr/Ph) ratio that the microorganisms of WF-LMX resided in 60 m–200 m deep shelf with anoxic bottom water. From SEM microphotographs and microbial microscopy analysis, it was demonstrated that the microorganisms in the WF-LMX can be divided into 3 types: planktonic algae (mainly including acritarchs and green algae), fungi, and benthic algae. Acritarchs were the most common microorganisms in the WF-LMX with the average relative content of 60.5%. The average relative contents of benthic algae, fungi, and green algae were 17.6%, 18.0% and 3.9%, respectively. Since the acritarchs and green algae in the Wufeng Formation and the Longmaxi Formation basically belong to planktonic algae, the relative content of planktonic algae in them is about 64.4%. The strata of WF-LMX can be divided into 3 sections based on the distribution characteristics of various microorganisms. The relative content of acritarchs gradually decreased upwards, while that of benthic algae gradually increased. The multiple proxies of biomarkers proved that the planktonic algae was the main source of organic matter in the WF-LMX. Combining the statistical data of microorganisms, it was considered that the organic matter in WF-LMX was mainly derived from acritarchs, which might be the components of planktonic algae. The fungi had a significant contribution to the organic matter in organic-rich layers (TOC > 2.0%) rather than in organic-poor layers, while green algae and benthic algae made little contribution to the organic matters in WF-LMX.

Distribution of phenols related to self-heating and water washing on coal-waste dumps and in coaly material from the Bierawka river (Poland)

Abstract Several types of coal waste (freshly-dumped waste, self-heated waste and waste eroded by rain water), river sediments and river water were sampled. The aim was to identify the types of phenols present on the dumps together with their relative abundances. Gas chromatography-mass spectrometry (GC-MS) analyses of a large number of samples (234) statistically underpin the phenol distributions in the sample sets. The largest average relative contents (1.17-13.3%) of phenols occur in the self-heated samples. In these, relatively high amounts of phenol, C1- and C2-phenols reflect the thermal destruction of vitrinite. In fresh coal waste, C2- and C3-phenols that originated from the bacterial/fungal degradation and oxidation of vitrinite particles are the most common (0.6 rel.%). Water-washed coal waste and water samples contain lower quantities of phenols. In the river sediments, the phenols present are the result of bacterial- or fungal decay of coaly organic matter or are of industrial origin.

Human placenta: relative content of antibodies of different classes and subclasses (IgG1-IgG4) containing lambda- and kappa-light chains and chimeric lambda-kappa-immunoglobulins.

The specific organ placenta is much more than a filter: it is an organ that protects, feeds and regulates the growth of the embryo. Affinity chromatography, ELISA, SDS-PAGE and matrix-assisted laser desorption ionization mass spectrometry were used. Using 10 intact human placentas deprived of blood, a quantitative analysis of average relative content [% of total immunoglobulins (Igs)] was carried out for the first time: (92.7), IgA (2.4), IgM (2.5), kappa-antibodies (51.4), lambda-antibodies (48.6), IgG1 (47.0), IgG2 (39.5), IgG3 (8.8) and IgG4 (4.3). It was shown for the first time that placenta contains sIgA (2.5%). In the classic paradigm, Igs represent products of clonal B-cell populations, each producing antibodies recognizing a single antigen. There is a common belief that IgGs in mammalian biological fluids are monovalent molecules having stable structures and two identical antigen-binding sites. However, similarly to human milk Igs, placenta antibodies undergo extensive half-molecule exchange and the IgG pool consists of 43.5 ± 15.0% kappa-kappa-IgGs and 41.6 ± 17.0% lambda-lambda-IgGs, while 15.0 ± 4.0% of the IgGs contained both kappa- and lambda-light chains. Kappa-kappa-IgGs and lambda-lambda-IgGs contained, respectively (%): IgG1 (47.7 and 34.4), IgG2 (36.3 and 44.5), IgG3 (7.4 and 11.8) and IgG4 (7.5 and 9.1), while chimeric kappa-lambda-IgGs consisted of (%): 43.5 IgG1, 41.0 IgG2, 5.6 IgG3 and 7.9 IgG4. Our data are indicative of the possibility of half-molecule exchange between placenta IgGs of various subclasses, raised against different antigens, which explains a very well-known polyspecificity and cross-reactivity of different human IgGs.

Comparison of antibodies hydrolyzing myelin basic protein from the cerebrospinal fluid and serum of patients with multiple sclerosis.

It was found that antibodies (Abs) against myelin basic protein (MBP) are the major components of the antibody response in multiple sclerosis (MS) patients. We have recently shown that IgGs from sera of MS patients are active in the hydrolysis of MBP. However, in literature there are no available data concerning possible MBP-hydrolyzing Abs in cerebrospinal fluid (CSF) of MS patients. We have shown that the average content of IgGs in their sera is about 195-fold higher than that in their CSF. Here we have compared, for the first time, the average content of lambda- and kappa-IgGs as well as IgGs of four different subclasses (IgG1-IgG4) in CSF and sera of MS patients. The average relative content of lambda-IgGs and kappa –IgGs in the case of CSFs (8.0 and 92.0%) and sera (12.3 and 87.7%) are comparable, while IgG1, IgG2, IgG3, and IgG4: CSF - 40.4, 49.0, 8.2, and 2.5% of total IgGs, respectively and the sera - 53.6, 36.0, 5.6, and 4.8%, decreased in different order. Electrophoretically and immunologically homogeneous IgGs were obtained by sequential affinity chromatography of the CSF proteins on protein G-Sepharose and FPLC gel filtration. We present first evidence showing that IgGs from CSF efficiently hydrolyze MBP and that their average specific catalytic activity is unpredictably ∼54-fold higher than that of Abs from sera of the same MS patients. Some possible reasons of these findings are discussed. We suggest that anti-MBP abzymes of CSF may promote important neuropathologic mechanisms in this chronic inflammatory disorder and in MS pathogenesis development.

Application of the Weng’s ratio for the identification of Zn, Cu, and Pb contamination in soils and sediments

This work explores the application of the use of Zn, Cu, and Pb relative contents as a new type of normalization method for geochemical properties of soils and sediments in an Atlantic Basin (Anllons River, NW Spain). The method is based on the conservative behavior of these elements, which exhibit a certain concentration ratio that remains stable as long as there are no human disturbances. The average relative contents of Zn, Cu, and Pb were calculated by dividing the concentration of each metal in soils or sediments, in the <63-μm fraction, by the sum of Zn, Cu, and Pb, expressed as a percentage. The evaluation of the sum of the average relative concentrations of Zn, Cu, and Pb (Ri), together with three standard deviations for each element, namely, Ri ± 3Si, allows a hexagon to be constructed, represented in ternary diagrams of Zn:Cu:Pb. Following the method proposed by Weng et al. (Environ Geol 45:79–85, 2003), those samples falling outside the hexagon must be considered outliers. Results obtained confimed the conservative behavior between the relative contents of Zn, Cu, and Pb in surficial samples (soils, bed, and suspended sediments). Only sediment cores displayed nonconservative behavior, showing a marked Pb enrichment, with respect to the surficial samples. When Zn, Cu, and Pb relative contents were plotted in ternary diagrams, outliers were best classified when the hexagon was drawn with standard deviations of samples from the study area. The hexagon drawn with an international database of soils and sediments showed a poorer classification of outliers. The results showed that total Zn, Cu, and Pb relative contents may be employed to investigate anthropogenic disturbances of these elements in soils and sediments of the Anllons River Basin, thus corroborating that this type of normalization may be employed as a tool to assess outliers in a contaminated area.

Differences in volatile ester composition between Fragaria × ananassa and F. vesca and implications for strawberry aroma patterns

Esters are a very important component of strawberry (Fragaria sp.) aroma. In this study, fruit volatiles were isolated by solid-phase microextraction and analyzed by gas chromatography–mass spectrometry (SPME/GC–MS). It was found that F.×ananassa had more esters than F. vesca, but there was no significant difference in average relative content of esters. Twenty five esters were selected as predominant esters, 16 of which were prevalent in F.×ananassa and another 16 in F. vesca. Among them, hexyl acetate, octyl acetate, ethyl butyrate, ethyl hexanoate, ethyl octanoate, methyl decanoate, and ethyl decanoate were found in both F.×ananassa and F. vesca, while 1-methyltridecyl acetate, myrtenyl acetate, trans-pinocarvyl acetate, and ethyl dodecanoate were only present in F. vesca. The numbers of carbons of the predominant esters in F.×ananassa were usually smaller than those of F. vesca. Ethyl hexanoate and octyl acetate were the esters with the highest average concentrations in F.×ananassa and F. vesca, respectively. It was found that hexyl acetate, methyl butyrate, hexyl butyrate, methyl hexanoate, and ethyl hexanoate were major contributors to the aroma of cultivated strawberry because their odor values were ≥1 in every cultivar, however, no ester was found to be so important like that for all of the F. vesca accessions. Most of the predominant esters of F.×ananassa were described as having only fruity odor. Unlike the case of F.×ananassa, nearly all of the predominant esters of F. vesca have a noticeable floral odor in addition to a fruity note. That may contribute to the variations in fruit aroma. The average number and proportion of acyl and alkyl esters differed between species. Acetate esters predominated in F. vesca, accounting for a significantly higher average proportion of total esters than in F.×ananassa. All the differences in volatile esters are likely to play a key role in the different aroma patterns of F.×ananassa and F. vesca.

Antisense suppression of alcohol acetyltransferase gene in ripening melon fruit alters volatile composition

Volatile esters are characteristic aroma components of melon (Cucumis melo L.) fruit. Alcohol acetyltransferase (AAT) (EC2.3.1.84) catalyzes the reactions of aliphatic and aromatic alcohols to their esters in the presence of acyl CoA in fruit and flowers. In this study, melon plants were transformed with a gene construct containing a melon AAT cDNA (AAT2) in an antisense orientation, driven by the constructive cauliflower mosaic virus 35S promoter, by ovary-injection transformation method. The transformed plants displayed a range of decreased AAT activities in the ripening fruit. The relative content of volatile esters was reduced, and the average relative content in the transgenic fruit was 78% of the wild-type fruit. However, the relative contents of aldehydes and alcohols increased; the average relative contents were 3.2 times and 2.4 times of those in the wild-type fruit, respectively. Apart from the difference in the volatile compounds, no other phenotypic alterations were noted, including other quality indices, such as the sugar, vitamin C and carotenoid contents. Our study indicates that AAT plays the key role in volatile ester formation in melon fruit.

Phenolic glucosides in bread containing flaxseed

Three phenolic glucosides, secoisolariciresinol diglucoside, p-coumaric acid glucoside and ferulic acid glucoside, were analyzed in commercial breads containing flaxseed. The total phenolic glucoside content ranged from 15 to 157mg/100g dry bread. Secoisolariciresinol diglucoside was the dominating phenolic glucoside with an average relative content of 62%, followed by p-coumaric acid glucoside (20%) and ferulic acid glucoside (18%). Strong positive correlations between the phenolic glucosides were found, indicating no major effect of raw material or bread-making process on the relative content of the phenolic glucosides in flaxseed.

Contribution of CYP3A4, CYP2B6, and CYP2C9 isoforms to N-demethylation of ketamine in human liver microsomes.

Ketamine is a widely used drug for its anesthetic and analgesic properties; it is also considered as a drug of abuse, as many cases of ketamine illegal consumption were reported. Ketamine is N-demethylated by liver microsomal cytochrome P450 into norketamine. The identification of the enzymes responsible for ketamine metabolism is of great importance in clinical practice. In the present study, we investigated the metabolism of ketamine in human liver microsomes at clinically relevant concentrations. Liver to plasma concentration ratio of ketamine was taken into consideration. Pooled human liver microsomes and human lymphoblast-expressed P450 isoforms were used. N-demethylation of ketamine was correlated with nifedipine oxidase activity (CYP3A4-specific marker reaction), and it was also correlated with S-mephenytoin N-demethylase activity (CYP2B6-specific marker reaction). Orphenadrine, a specific inhibitor to CYP2B6, and ketoconazole, a specific inhibitor to CYP3A4, inhibited the N-demethylation of ketamine in human liver microsomes. In human lymphoblast-expressed P450, the activities of CYP2B6 were higher than those of CYP3A4 and CYP2C9 at three concentrations of ketamine, 0.005, 0.05, and 0.5 mM. When these results were extrapolated using the average relative content of these P450 isoforms in human liver, CYP3A4 was the major enzyme involved in ketamine N-demethylation. The present study demonstrates that CYP3A4 is the principal enzyme responsible for ketamine N-demethylation in human liver microsomes and that CYP2B6 and CYP2C9 have a minor contribution to ketamine N-demethylation at therapeutic concentrations of the drug.

A high accumulation of minerals in human internal jugular vein.

To elucidate age-related changes of mineral contents in human veins, the relative contents (RCs) of elements in the human internal jugular veins, superior and inferior venae cavae, and femoral veins from 27 subjects ranging from 40 to 98 yr old were analyzed by inductively coupled plasma atomic emission spectrometry. The average RCs of calcium in the 27 specimens were the highest in the internal jugular vein, followed in descending order by the superior vena cava, femoral vein, and inferior vena cava. The RCs of calcium and phosphorus in the internal jugular veins started to increase after the age of 50 yr, became the highest in subjects in their 60s and thereafter decreased gradually. It is noted that such accumulations of minerals, similar to the internal jugular vein, were also found in the veins, such as the superior and inferior venae cavae, and femoral vein. Accumulation of minerals in the veins is different from that of arteries, which increase progressively by aging, but do not decrease.

Modification of ricin and its hepatotoxicity and activity against hepatocellular cancer in mice.

AIM:To observe the effects of ricin (RT) with and without chemical modification on both hepatotoxicity of mice and activity against hepatocellular cancer (HCC), and evaluate the possibility to improve RT anticancer activity via chemical modification.METHODS:RT was modified with N-succinimidyl3(2-pyridyldithio) propionate (SPDP),a heterobifunctional cross-linker, and SPDP derivative of RT (PDP-R) was obtained.The serum glutathione-s-transferase (SGST) activity,as an index of liver damage, was determined in mice intoxicated with RT and PDP-R,at various doses and time.The tissue damage of HCC in the nude mice ip injected with PDP-R was compared with that with RT at the same dose by immunohistochemical method, the relative content of both RT and PDP-R in the HCC tissues was measured by computerized image-analysis. RESULTS:The SGST activities increased with doses or/and time intoxicated with both RT and PDP-R, and the increase in the value of RT group was more significant than that in the PDP-R group; the SGST activity of RT group was 2.8-fold (P < 0.01) of PDP-R group at a dose of 12.5&mgr;g/kg for 42h, showing the much lower toxicity of R-PDP than that of RT. Under an optical microscope, hemolysis and necrosis of massive cells in the HCC tissues of PDP-R group were observed and the ratio of necrosis mounted to 90.5% while the corresponding value of RT group only to 62.5%.With computerized image-analysis, the average relative content of RT and PDP-R in the HCC tissues,represented as greyness, was 140.06 plus minus 3.43 and 169.10 plus minus 2.74, respectively. There was significant difference between the two (P< 0.05), indicating the higher content of PDP-R in the HCC tissue than that of RT.CONCLUSION:The hepatotoxicity of PDP-R to mice may be reduced by chemical modification with SPDP, but both the affinity of PDP-R to the HCC tissues and ability to kill it may be stronger than that of RT. So this might be a valuable attempt to improve the anticancer activity of RT.

Age-independent constancy of mineral contents in human vertebra and auditory ossicle.

To elucidate age-related changes of mineral contents in human bones, element contents of human vertebrae and auditory ossicles were determined by inductively coupled plasma atomic-emission spectrometry. The cervical, thoracic, and lumbar vertebrae were removed from 12 vertebral columns. The mallei of auditory ossicle were removed from 27 cadavers. It was found that average relative contents (RCs) of calcium and phosphorus in cervical, thoracic, and lumbar vertebrae remained almost constant within ages ranging from 46 to 99 y. In addition, it was found that the RCs of calcium and phosphorus in men's and women's mallei remained constant within ages ranging from 40 to 98 yr. These results support the view that there is no significant age-dependent change of mineral contents in human bones.

High accumulation of elements in the human femoral artery.

The relative contents (RCs) of elements in the femoral arteries as well as the thoracic aorta, coronary, basilar, and radial arteries from 26 subjects within the age range between 55 and 92 yr old, were analyzed by inductively coupled plasma atomic emission spectrometry. The RCs of calcium and phosphorus in the femoral arteries started to increase before the age of 60 yr. The RCs of magnesium increased after the age of 70 yr. However, the RCs of sulfur did not change significantly within the age range between 55 and 92 yr. With regard to localization of the mineral accumulations in the femoral arterial wall, it was found that the accumulations of calcium and phosphorus occurred only in the tunica media, only in the tunica intima, or in both the tunica media and the tunica intima. The manner of accumulation of calcium and phosphorus in the femoral arterial wall was different from that in the aortic wall. The average RCs of calcium in the 26 specimens were the highest in the femoral artery, followed in descending order by the thoracic aorta, coronary, basilar, and radial arteries. The average RCs of phosphorus were highest in the thoracic aorta, followed by the coronary, femoral, basilar, and radial arteries. It is noted that the accumulation of mineral elements never occurred uniformly in all the arteries.