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1.
The composition of the epicuticular leaf n‐alkanes of eight populations of three Satureja montana subspecies (S. montana L. subsp. pisidica (Wettst.) ?ili? , S. montana L. subsp. montana, and S. montana L. subsp. variegata (Host ) P. W. Ball ), from central and western areas of the Balkan Peninsula was characterized by GC‐FID and GC/MS analyses. In the leaf waxes, 15 n‐alkane homologs with chain‐lengths ranging from C21 to C35 were identified. The main n‐alkane in almost all samples was n‐nonacosane (C29), but differences in the contents of three other dominant n‐alkanes allowed separating the coastal from the continental populations. The diversity and variability of the epicuticular‐leaf‐n‐alkane patterns and their relation to different geographic and bioclimatic parameters were analyzed by several statistical methods (principal component, discriminant, and cluster analyses as well as the Mantel test). All tests showed a high correlation between the leaf n‐alkane pattern and the geographical distribution of the investigated populations, confirming the differentiation between S. montana subsp. pisidica and the other two subspecies. The S. montana subsp. variegata and S. montana subsp. montana populations are geographically closer and their differentiation according to the leaf‐n‐alkane patterns was not clear, even though there was some indication of discrimination between them. Moreover, most of the bioclimatic parameters related to temperature were highly correlated with the differentiation of the coastal and the continental populations.  相似文献   

2.
The chemical composition of epicuticular waxes of nine populations from three Pinus nigra J. F. Arnold subspecies (namely subsp. nigra, subsp. banatica (Borbás ) Novák , and subsp. pallasiana (Lamb .) Holmboe ) from Southern Carpathians and central Balkan Peninsula were analyzed using GC/MS and GC/FID chromatography, and multivariate statistical techniques with respect to biogeography and taxonomy. In the needle waxes, four primary alcohols and 14 n‐alkanes ranging from C21 to C33 were identified, and the most abundant compounds were the four odd‐numbered n‐alkanes C27, C25, C23, and C29. Multivariate statistical analyses (CDA and CA) have shown existence of three P. nigra groups and suggested clinal differentiation as a mechanism of genetic variation across a geographic area: the first group consisted of the southernmost populations of subsp. pallasiana from Macedonia, the second consisted of the northernmost subsp. banatica populations from Romania, while all populations in Serbia described as three different subspecies (nigra, banatica, and pallasiana) formed the third group together with subsp. nigra population from Bosnia and Herzegovina. According to simple linear regression, geographic latitude and four bioclimatic parameters were moderately correlated with the contents of epicuticular wax compounds that are important in population discrimination, while stepwise multiple regression showed that latitude participated in most of the regression models for predicting the composition of the epicuticular waxes. These results agree with CDA and CA analysis, and confirmed the possibility of recognition of fine geographic differentiation of the analyzed P. nigra populations.  相似文献   

3.
The composition of the epicuticular n‐alkanes isolated from the leaves of ten populations of Juniperus communis L. var. saxatilis Pallas from central (continental) and western (coastal) areas of the Balkan Peninsula was characterized by GC‐FID and GC/MS analyses. In the leaf waxes, 14 n‐alkane homologues with chain‐lengths ranging from C22 to C35 were identified. All samples were dominated by n‐tritriacontane (C33), but differences in two other dominant n‐alkanes allowed separating the coastal from the continental populations. Several statistical methods (ANOVA, principal component, discriminant, and cluster analyses as well as the Mantel test) were deployed to analyze the diversity and variability of the epicuticular‐leaf‐n‐alkane patterns of the ten natural populations of J. communis var. saxatilis and their relation to different geographic and bioclimatic parameters. Cluster analysis showed a high correlation of the leaf‐n‐alkane patterns with the geographical distribution of the investigated samples, differentiating the coastal from the continental populations of this taxon. Several bioclimatic parameters related to aridity were highly correlated with this differentiation.  相似文献   

4.
The n‐alkane composition in the leaf cuticular waxes of natural populations of Bosnian pine (Pinus heldreichii), Austrian pine (P. nigra), and Macedonian pine (P. peuce) was compared for the first time. The range of n‐alkanes was wider in P. nigra (C16 – C33) than in P. heldreichii and P. peuce (C18 – C33). Species also diverged in abundance and range of dominant n‐alkanes (P. heldreichii: C23, C27, and C25; P. nigra: C25, C27, C29, and C23; P. peuce: C29, C25, C27, and C23). Multivariate statistical analyses (PCA, DA, and CA) generally pointed out separation of populations of P. nigra from populations of P. heldreichii and P. peuce (which were, to a greater or lesser extent, separated too). However, position of these species on the basis of n‐alkane composition was in accordance neither with infrageneric classification nor with recent molecular and terpene investigations.  相似文献   

5.
The composition of the cuticular n‐alkanes isolated from the leaves of nine populations of Juniperus deltoides R.P.Adams from continental and coastal areas of the Balkan Peninsula was characterized by GC‐FID and GC/MS analyses. In the leaf waxes, 14 n‐alkane homologues with chain‐lengths ranging from C22 to C35 were identified. n‐Tritriacontane (C33) was dominant in the waxes of all populations, but variations between the populations in the contents of all n‐alkanes were observed. Several statistical methods (ANOVA, principal component, discriminant, and cluster analyses) were used to investigate the diversity and variability of the cuticular‐leaf‐n‐alkane patterns of the nine J. deltoides populations. This is the first report on the n‐alkane composition for this species. The multivariate statistical analyses evidenced a high correlation of the leaf‐n‐alkane pattern with the geographical distribution of the investigated samples, differentiating the coastal from the continental populations of this taxon.  相似文献   

6.
This is the first report of population variability of the contents of n‐alkanes and nonacosan‐10‐ol in the needle epicuticular waxes of Serbian spruce (Picea omorika). The hexane extracts of needle samples originated from three natural populations in Serbia (Vranjak, Zmajeva?ki potok, and Mile?evka Canyon) were investigated by GC and GC/MS analyses. The amount of nonacosan‐10‐ol varied individually from 50.05 to 74.42% (65.74% in average), but the differences between the three investigated populations were not statistically confirmed. The results exhibited variability of the composition of n‐alkanes in the epicuticular waxes with their size ranging from C18 to C35. The most abundant n‐alkanes were C29, C31, and C27 (35.22, 13.77, and 12.28% in average, resp.). The carbon preference index of all the n‐alkanes (CPItotal) of the P. omorika populations (average of populations IIII) ranged from 3.3 to 11.5 (mean of 5.9), while the average chain length (ACL) ranged from 26.6 to 29.2. The principal component and cluster analyses of the contents of nine n‐alkanes showed the greatest difference for the population growing in the Mile?evka Canyon. The obtained results were compared with previous literature data given for other Picea species, and this comparison was briefly discussed.  相似文献   

7.
This is the first report of individual variability and population diversity of the contents of nonacosan‐10‐ol and n‐alkanes in the needle cuticular waxes of Bosnian pines originated from Montenegro, regarded as Pinus heldreichii var. leucodermis, and from Serbia, regarded as P. heldreichii var. pan?i?i. The amount of nonacosan‐10‐ol varied individually from 27.4 to 73.2% (55.5% in average), but differences between the four investigated populations were not statistically confirmed. The size of the n‐alkanes ranged from C18 to C33. The most abundant n‐alkanes were C23, C27, and C25 (12.2, 11.2, and 10.8% in average, resp.). The carbon preference index (CPI) of the n‐alkanes ranged from 0.8 to 3.1 (1.6 in average), while the average chain length (ACL) ranged from 20.9 to 26.5 (24.4 in average). Long‐chain and mid‐chain n‐alkanes prevailed (49.6 and 37.9% in average, resp.). It was also found that the populations of P. heldreichii var. leucodermis had predominantly a narrower range of n‐alkanes (C18? C31) than the trees of the variety pan?i?i (C18? C33). Differences between the varieties were also significant for most of the other characteristics of the n‐alkane pattern (e.g., most abundant n‐alkanes, CPI, ACL, and relative proportion of short‐, mid‐, and long‐chain n‐alkanes). The principle component and cluster analyses of eleven n‐alkanes confirmed the significant diversity of these two varieties.  相似文献   

8.
For the first time, the n‐alkane distribution and variability of the epicuticular waxes within 22 Sedum taxa was reported with focus on the chemotaxonomy of native Sedum representatives from the central Balkan Peninsula, compared to their relations with four other species of the Crassulaceae family. By GC/MS and GC‐FID identification and quantification, it was established that n‐alkanes C27, C29, C31, C33, and C35 were the dominant constituents of the examined epicuticular wax samples. Applying multivariate statistical analyses including agglomerative hierarchical clustering (AHC) and principal component analysis (PCA), the relation according to the n‐alkane composition between the examined samples was established. It was shown that the n‐alkane variability of the central Balkan Sedum species was considerable and that n‐alkanes might not be very reliable taxonomic markers for these species.  相似文献   

9.
The n‐alkane composition and the nonacosan‐10‐ol content in the needle cuticular waxes of Serbian spruce (Picea omorika), Bosnian pine (Pinus heldreichii), and Macedonian pine (Pinus peuce) were compared. The amount of nonacosan‐10‐ol in the needle waxes of P. omorika was higher than those in P. heldreichii and P. peuce. The range of n‐alkanes was also wider in P. omorika (C18–C35) than in P. heldreichii and P. peuce (C18–C33). The dominant n‐alkanes were C29 in the needle waxes of P. omorika, C23, C27, and C25 in those of P. heldreichii, and C29, C25, C27, and C23 in those of P. peuce. The waxes of P. omorika contained higher amounts of n‐alkanes C29, C31, and C33, while those of P. heldreichii and P. peuce had higher contents of n‐alkanes C21, C22, C23, C24, and C26. The principal component analysis of the contents of nine n‐alkanes showed a clear separation of the Serbian spruce populations from those of the two investigated pine species, which partially overlapped. The separation of the species was due to high contents of the n‐alkanes C29 and C31 (P. omorika), C19, C20, C21, C22, C23, and C24 (P. heldreichii), and C28 (P. peuce). Cluster analysis also showed a clear separation between the P. omorika populations on one side and the P. heldreichii and P. peuce populations on the other side. The n‐alkane and terpene compositions are discussed in the light of their usefulness in chemotaxonomy as well as with regard to the biogeography and phylogeny of these rare and endemic conifers.  相似文献   

10.
This is the first report on the composition and variability of the needle‐wax n‐alkanes in natural populations of Pinus nigra in Serbia. Samples of 195 trees from seven populations belonging to several infraspecific taxa (ssp. nigra, var. gocensis, ssp. pallasiana, and var. banatica) were analyzed. In general, the size of the n‐alkanes ranged from C16 to C33, with the exception of ssp. nigra, for which it ranged from C18 to C33. The most abundant were C23‐, C25‐, C27‐, and C29‐alkanes. The needle waxes of Populations IIII and V were characterized by a higher content of C23‐, C25‐, and C27‐alkanes and a lower content of C24‐, C26‐, C28‐, and C30‐alkanes, compared to the other populations, and the trees of these populations could be assigned to ssp. nigra. The samples of Population VI were characterized by higher amounts of C22‐, C24‐, C30‐, and C32‐alkanes and lower amounts of C25‐ and C27‐alkanes, and the trees could be considered as ssp. pallasiana. The samples of Population VII, consisting of trees belonging to var. banatica, were richer in C29‐, C31‐, and C33‐alkanes. The wax compositions of Populations IV and V, both composed of trees previously determined as P. nigra var. gocensis, showed a tendency of splitting. Indeed, the alkane composition of Population IV was closer to that of ssp. pallasiana pines, while that of Population V was more similar to that of ssp. nigra pines. From the results presented here, it is obvious that in the central part of the Balkan Peninsula, significant diversification and differentiation of the populations of black pine exists, and these populations could be defined as different intraspecific taxa. Our results also indicate the validity of n‐alkanes as chemotaxonomic characters within this aggregate.  相似文献   

11.
It remains poorly understood how the composition of leaf wax n‐alkanes reflects the local environment. This knowledge gap inhibits the interpretation of plant responses to the environment at the community level and, by extension, inhibits the applicability of n‐alkane patterns as a proxy for past environments. Here, we studied the n‐alkane patterns of five Miconia species and one Guarea species, in the Ecuadorian Andes (653–3,507 m a.s.l.). We tested for species‐specific responses in the average chain length (ACL), the C31/(C31 + C29) ratio (ratio), and individual odd n‐alkane chain lengths across an altitudinally driven environmental gradient (mean annual temperature, mean annual relative air humidity, and mean annual precipitation). We found significant correlations between the environmental gradients and species‐specific ACL and ratio, but with varying magnitude and direction. We found that the n‐alkane patterns are species‐specific at the individual chain length level, which could explain the high variance in metrics like ACL and ratio. Although we find species‐specific sensitivity and responses in leaf n‐alkanes, we also find a general decrease in “shorter” (<C29) and an increase in “longer” (>C31) chain lengths with the environmental gradients, most strongly with temperature, suggesting n‐alkanes are useful for reconstructing past environments.  相似文献   

12.
This is the first report on population variability of nonacosan‐10‐ol and n‐alkanes in needle epicuticular waxes of Macedonian pine (Pinus peuce Griseb .) Hexane extracts of needle samples, originating from two natural populations in Montenegro (Zeletin and Sjekirica) and from one population in Serbia (Mokra Gora) were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The amount of nonacosan‐10‐ol varied individually from 41.3 to 72.31% (average 55.9%), with the Sjekirica population being statistically divergent (64.4% on average). The results showed n‐alkanes in epicuticular waxes ranging from C18 to C33. The most abundant alkanes were C29, C25, C27, and C23 (15.5, 11.1, 10.6, and 10.5% on average, resp.). The carbon preference index of Pinus peuce ranged from 1.0 to 4.3 (1.9 on average). Average chain length ranged from 18.4 to 27.7 (average 25.7). A high level of inidividual quantitative variation in all of these hydrocarbon parameters was also detected. These results were compared with published data on other species from the Pinus genus.  相似文献   

13.
Plantago major L. grows in a very wide range of regions in China and exhibits great variations among populations. The analysis of the cuticular‐wax composition provides a potential approach to classify populations of P. major confronting different environmental conditions. Twelve populations of P. major and five populations of P. depressa Willd ., distributed over regions with average annual temperatures ranging from ?2.0 to 18.4°, were sampled, the variation of the composition of their cuticular waxes was analyzed, and their values of average chain length (ACL) and carbon preference index (CPI) were calculated. Great intra‐ and interspecies variations were observed for the total wax contents. The average annual temperature of the habitats was significantly correlated with the relative contents of the dominant n‐alkanes with an odd number of C‐atoms, but not with the wax contents. With an increasing average annual temperature, the relative contents of n‐alkanes C29 and C31 decreased, whereas those of C33 and C35 as well as the values of ACLtotal and ACL27–33 increased. Cluster analysis based on the pattern of the n‐alkane distribution allowed to clearly separate the populations of P. major according to the average annual temperature of their habitats, but not to separate the populations of the two species. Hence, the pattern of the n‐alkane distribution might be a good taxonomic marker for P. major at the intraspecies level, but not at the interspecies level. Nevertheless, a small difference between the populations of the two species was observed concerning the values of ACLtotal and CPItotal, implying the potential use of these indices for the classification of the populations of the two species at the interspecies level.  相似文献   

14.
Rapid global industrialization in the past decades has led to extensive utilization of fossil fuels, which resulted in pressing environmental problems due to excessive carbon emission. This prompted increasing interest in developing advanced biofuels with higher energy density to substitute fossil fuels and bio‐alkane has gained attention as an ideal drop‐in fuel candidate. Production of alkanes in bacteria has been widely studied but studies on the utilization of the robust yeast host, Saccharomyces cerevisiae, for alkane biosynthesis have been lacking. In this proof‐of‐principle study, we present the unprecedented engineering of S. cerevisiae for conversion of free fatty acids to alkanes. A fatty acid α‐dioxygenase from Oryza sativa (rice) was expressed in S. cerevisiae to transform C12–18 free fatty acids to C11–17 aldehydes. Co‐expression of a cyanobacterial aldehyde deformylating oxygenase converted the aldehydes to the desired alkanes. We demonstrated the versatility of the pathway by performing whole‐cell biocatalytic conversion of exogenous free fatty acid feedstocks into alkanes as well as introducing the pathway into a free fatty acid overproducer for de novo production of alkanes from simple sugar. The results from this work are anticipated to advance the development of yeast hosts for alkane production. Biotechnol. Bioeng. 2017;114: 232–237. © 2016 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.  相似文献   

15.
Aims: Investigation of the alkane‐degrading properties of Dietzia sp. H0B, one of the isolated Corynebacterineae strains that became dominant after the Prestige oil spill. Methods and Results: Using molecular and chemical analyses, the alkane‐degrading properties of strain Dietzia sp. H0B were analysed. This Grampositive isolate was able to grow on n‐alkanes ranging from C12 to C38 and branched alkanes (pristane and phytane). 8‐Hexadecene was detected as an intermediate of hexadecane degradation by Dietzia H0B, suggesting a novel alkane‐degrading pathway in this strain. Three putative alkane hydroxylase genes (one alkB homologue and two CYP153 gene homologues of cytochrome P450 family) were PCR‐amplified from Dietzia H0B and differed from previously known hydroxylase genes, which might be related to the novel degrading activity observed on Dietzia H0B. The alkane degradation activity and the alkB and CYP153 gene expression were observed constitutively regardless of the presence of the substrate, suggesting additional, novel pathways for alkane degradation. Conclusions: The results from this study suggest novel alkane‐degrading pathways in Dietzia H0B and a genetic background coding for two different putative oil‐degrading enzymes, which is mostly unexplored and worth to be subject of further functional analysis. Significance and Impact of the Study: This study increases the scarce information available about the genetic background of alkane degradation in genus Dietzia and suggests new pathways and novel expression mechanisms of alkane degradation.  相似文献   

16.
17.
Iso‐alkanes comprise a substantial proportion of petroleum and refined products that impact the environment, but their fate is cryptic under methanogenic conditions. We investigated methanogenic biodegradation of C7 and C8 iso‐alkanes found in naphtha, specifically 2‐methylhexane, 3‐methylhexane, 2‐methylheptane, 4‐methylheptane and 3‐ethylhexane. These were incubated as a mixture or individually with enrichment cultures derived from oil sands tailings ponds that generate methane from naphtha components; substrate depletion and methane production were monitored for up to 663 days. 3‐Methylhexane and 4‐methylheptane were degraded both singly and in the mixture, whereas 2‐methylhexane and 2‐methylheptane resisted degradation as single substrates but were depleted in the iso‐alkane mixture, suggesting co‐metabolism. 3‐Ethylhexane was degraded neither singly nor with co‐substrates. Putative metabolites consistent with succinylated C7 and C8 were detected, suggesting activation by addition of iso‐alkanes to fumarate and corresponding to detection of alkylsuccinate synthase‐like genes. 454 pyrotag sequencing, cloning and terminal restriction fragment length polymorphism of 16S rRNA genes revealed predominance of a novel member of the family Peptococcaceae (order Clostridiales) and Archaea affiliated with Methanoregula and Methanosaeta. We report here isomer‐specific metabolism of C7‐C8 iso‐alkanes under methanogenic conditions and propose their activation by a novel Peptococcaceae via addition to fumarate.  相似文献   

18.
Morphological and cytological characters were analysed among thirty populations of the genus Dactylis L. from Algeria, to understand its infraspecific diversity. Principal Component Analysis using quantitative characters allowed discriminating the tetraploid populations into two subspecies, marina (Borrill) Greuter, localised on sea cliffs, and hispanica (Roth) Nyman, very widespread. Some individuals of these latest populations formed a distinct group, identified as subsp. glomerata Hayek. Three diploid taxa are described in the literature: subspecies santai Stebbins & Zohary, castellata Parker & Borrill and mairei Stebbins & Zohary that are considered as prevalent in Algeria, distributed in Tellian Atlas, in forest ecosystems within mesophytic habitats. Canonical Discriminant Analysis on natural populations and on experimental cultures showed two main groups: the first group corresponds to subspecies mairei, with a narrow distribution; the second one exhibits a wide morphological variability and belongs to santai type. Based on this study, a key to aid in identification of the subspecies is presented.  相似文献   

19.
Cistus genus is widespread in the Mediterranean regions with several species and is traditionally known as a natural remedy, but few previous phytochemical researches have been reported on Cistus species growing in Sardinia. The aim of this work was to study the interpopulation variability of the volatiles of C. creticus subsp. eriocephalus to find out the natural chemotypes of this taxon for chemotaxonomic purposes. Plant material was collected from seven wild populations in Sardinia. The oils from aerial part were obtained by hydrodistillation and analyzed by GC/MS enabling to identify 185 compounds. The seven samples showed appreciable variations in their chemical composition. MA was found almost exclusively linear hydrocarbons (85%) and MN presented fatty acids (36.97%) as major fraction. CP and MN had high quantity of non‐terpenic carbonylic compounds (63% and 69%, respectively) and in CP was found also sclareol, a well‐known antimicrobial compound. PCA analysis showed the existence of a high interpopulation variability within the essential oils of C. creticus subsp. eriocephalus growing in Sardinia. For example, MN and CP are very close to each other as CG is close to PM. BN is isolated from the others Cistus populations due to lacking essential oil. These data suggest that the basis of variation in the volatile composition of seven C. creticus subsp. eriocephalus populations depends on hybridization and that the sample without essential oil is the only one no‐hybridized.  相似文献   

20.
The phytochemical composition and the antioxidant activities of the essential oil, as well as methanol and hot water extracts of endemic Satureja subspicata Vis . growing in Bosnia and Herzegovina (BiH), were described. β‐Caryophyllene, cisβ‐ocimene, and α‐pinene, identified by GC/MS and GC‐FID, were the dominant oil components. The major compound of both of extracts, identified by HPLC‐DAD, was rosmarinic acid. The analyzed essential oil showed moderate antioxidant activity. In this first report on the extracts of S. subspicata growing in BiH, the obtained results showed a high content of rosmarinic acid, as well as considerable amount of total phenols and flavonoids. Compared to the hot water extract, the methanol extract exhibits higher antioxidant potential, measured by DPPH and FRAP assay (IC50 = 0.45 g/l and 1879.43 equiv. Fe2+ μm ), while the hot water extract showed higher potential in inhibition of linoleic acid oxidation (51.7% and 61.5% for 1 and 10 g/l). A good antioxidant potential of the tested extracts indicates their potential use as antioxidants, particularly for lipid protection, and partly explains the justification of the use of this plant in traditional medicine of BiH.  相似文献   

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