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1.
The elemental composition of 10 methanogenic species was determined by inductively coupled plasma emission spectrometry and by a C-H-N-analyzer. The 10 species were representative of all three orders of the methanogens and were cultivated under defined conditions. Special emphasis was given toMethanosarcina barkeri, represented by 5 strains and cultivated on various substrates. The following elements with the lowest and highest values in parentheses were determined: C (37–44%, w/w), H (5.5–6.5%), N (9.5–12,8%); Na (0.3–4.0%), K (0.13–5.0%), S (0.56–1.2%), P (0.5–2.8%), Ca (order I: 85–550 ppm; order II: 1000–4500 ppm), Mg (0.09–0.53%), Fe (0.07–0.28%), Ni (65–180 ppm), Co (10–120 ppm). Mo (10–70 ppm), Zn (50–630 ppm), Cu (<10–160 ppm), Mn (<5–25 ppm). The biggest variations were found with respect to N and K, which both seem to have important physiological functions. Although it is unknown whether zinc and copper are essential trace elements for methanogens, all investigated species contained remarkably high zinc contents, whereas copper seemed to be present only in some species.  相似文献   

2.
《Palaeoworld》2022,31(3):507-520
We compiled the Cretaceous sporopollen fossil data from 19 locations of six provinces in South China, reviewed the affinities of spore and pollen genera by examining and assessing these fossils with published data, and associated them with the sporomorph eco-groups (SEG) model and vegetation type. Seven palynofloral assemblages (PA1–PA7) were identified. PA1 (Berriasian–Valanginian) and PA2 (Hauterivian–Barremian) mainly include Cheirolepidiaceae (~60–80%), Cycadophytes (~10%), and Lygodiaceae (~10%), indicating warm and dry climate; PA3 (Aptian) and PA4 (Albian) represent warm, semi-arid to semi-humid climate with vegetation composed of Araucariaceae (~10%), Cheirolepidiaceae (~40–60%), Cycadophytes (~10%), and Lygodiaceae (~10%); PA5 (Cenomanian–Turonian) and PA6 (Coniacian–Santonian) imply a hot, semi-humid to humid climate with the vegetation taxa of Lygodiaceae (~20–40%), Cheirolepidiaceae (~20–50%), Ephedraceae (~5–8%), and Araucariaceae (~10%); and PA7 (Campanian–Maastrichtian) indicates a relatively cool and dry climate evidenced by the vegetation composition of Cheirolepidiaceae (~30–40%), Pteridaceae (~10%), Ephedraceae (~5–8%), and Ulmaceae (~30–40%). Our SEG analysis reveals three climatic evolution phases: the Berriasian–Barremian warm-dry phase, the Aptian–Santonian warm-wet phase, and the Campanian–Maastrichtian cool-dry phase. The climatic variation pattern is compatible with that indicated by fossil stomatal pCO2 values and the pCO2 simulation of GEOCARB II and III models, providing independent climatic proxies of the region and contributing to better understanding of the global Cretaceous climatic changes.  相似文献   

3.
The distribution of Cd (II) and Pb (II) among amino acids in parenteral nutrition formulations was investigated by coupling ion-chromatography (HPLC/IC) and electrothermal atomic absorption spectrometry. The methodology was based on ion-exchange separation and fluorimetric amino acid detection after post-column derivatization. Cd (II) and Pb (II) were assayed in 500-µL fractions of the column effluent. The distribution of Cd (II) and Pb (II) in alanine (Ala), aspartic acid (Asp), glutamic acid (Glu), glycine (Gly), histidine (His), methionine (Met), phenylalanine (Phe), serine (Ser), and threonine (Thr) were analyzed by monitoring changes in the concentration of free amino acids by HPLC/IC. The results indicated that Cd (II) and Pb (II) were distributed according to the following trend: Gly–Cd?>?Gly–Pb?>?Ala–Cd?>?Ala–Pb?>?His–Cd?~?His–Pb?>?Thr–Cd?>?Thr–Pb?>?Phe–Cd?~?Phe–Pb?~?Asp–Cd?~?Asp–Pb?~?Met–Cd?~?Met–Pb?~?Glu–Cd?~?Glu–Pb?>?Ser–Cd?~?Ser–Pb. The effects of amino acid concentration and stability constants of amino acid–metal complexes are discussed.  相似文献   

4.
A new species of snake eel (family Ophichthidae, subfamily Ophichthinae), Apterichtus hatookai, is described based on the 478.5 mm holotype and three paratypes, 265.0–519.4 mm in total length (TL), collected from the Pacific Ocean, off the coasts of Shikoku Island and central Honshu Island, Japan. The new species can be distinguished from its congeners, except for Apterichtus monodi and Apterichtus orientalis, by having seven supratemporal pores. The new species is distinguishable from A. monodi by having a longer tail (60.4–62.0 % TL vs. 57.4–60.2 %), four preopercular pores (vs. three), fewer lateral-line pores before the anus (54–58 vs. 63–68), and fewer total vertebrae (137–141 vs. 142–151). Apterichtus hatookai differs from A. orientalis in having a shorter head (5.1–6.1 % TL vs. 7.1–8.1 %; 13.3–16.0 % of preanal length vs. 16.2–18.0 %), a longer tail (60.4–62.0 % TL vs. 54.8–56.0 %), lower body depth at gill opening (0.9–1.5 % TL vs. 1.8–1.9; 2.3–3.8 % of preanal length vs. 4.1–4.2 %), more numerous total vertebrae (137–141 vs. 131–133), and by the anterior tip of the lower jaw below the center of the eye (vs. anterior to a vertical through anterior margin of eye).  相似文献   

5.
The rat pituitary contains an enzyme which will acetylate certain corticotropin (ACTH) fragments using acetyl coenzyme A (AcCoA). This acetyltransferase activity was found in all three lobes of the rat pituitary. The enzyme was largely particulate in nature. The enzyme sedimenting at 27,000 and 100,000g had specific activities 4–10 times greater than the soluble fraction. The acetyltransferase activity was dependent on substrate concentration (ACTH), was linear with time, and was inactivated at 55 °C. The enzyme would acetylate ACTH (1–24), (1–10), and (4–10), but would not use ACTH (2–10), (3–10), or (1–8) as substrates. The apparent Km values for the substrates were as follows: AcCoA, 2.2 μm ACTH (1–24), 4.2 μm; ACTH (1–10), 96 μm; and ACTH (4–10), 37 μm.  相似文献   

6.
Hydrodistillation of the dried leaves of five species of the genus Eucalyptus L' Hér ., viz., E. dundasii Maiden , E. globulus Labill ., E. kitsoniana Maiden , E. leucoxylon F. Muell ., and E. populifolia Hook ., harvested from Jbel Abderrahman arboreta (region of Nabeul, northeast of Tunisia) in April 2006, afforded essential oils in yields varying from 0.9±0.3 to 3.8±0.6%, dependent on the species. E. globulus and E. Kitsoniana provided the highest and the lowest percentage of essential oil amongst the species examined, respectively. Analysis by GC (RI) and GC/MS allowed the identification of 127 compounds, representing 93.8 to 98.7% of the total oil composition. The contents of the different samples varied according to the species. The main components were 1,8‐cineole ( 2 ; 4.7–59.2%), followed by α‐pinene ( 1 ; 1.9–23.6%), trans‐pinocarveol ( 6 ; 3.5–21.6%), globulol ( 8 ; 4.3–12.8%), p‐cymene ( 3 ; 0.5–6.7%), α‐terpineol (1.5–4.5%), borneol (0.2–4.4%), pinocarvone (1.1–3.8%), aromadendrene (1.4–3.4%), isospathulenol (0.0–1.9%), fenchol ( 4 ; 0.1–2.5%), limonene (1.0–2.4%), epiglobulol (0.6–2.1%), viridiflorol ( 9 ; 0.8–1.8%), and spathulenol (0.1–1.6%). E. leucoxylon was the richest species in 2 . Principal component analysis (PCA) and hierarchical cluster analysis (HCA) separated the five Eucalyptus leaf essential oils into four groups, each constituting a chemotype.  相似文献   

7.
Chemical biodiversity of essential oils of natural populations of Deverra scoparia growing in different regions in Algeria, and spreading from of semiarid to Saharan territories, was assessed. More than 60 compounds were identified by GC and GC-MS. Both phenylpropanoids and phathalids classes of bioactive components in leaves part were exhibiting drastic variations: (0.77–59.46%) and (0.04–28.55%), respectively. More specifically, the following bioactive components reached a very high level for this plant species: myristicin “up to 58.19%”, dill apiole “up to 25.52%” and (Z)-ligustilide “up to 27.5%”. Seven major compounds identified for the flowers part were varying from very low to very high percentages: α-pinene (2.49–42.32%), sabinene + β-pinene (1.11–30.31%), α-phellandrene (0.99–20.63%), p-cymene (0.0–44.22%), limonene (0.0–42.99%), myristicin (0.03–58.19%) and dill apiole (0.4–25.52%). Similarly, for the stems part, larges variations of both major and minor components were also registered: α-pinene (17.97–53.25%), sabinene + β-pinene (3.44–24.99%), α-phellandrene (0.75–10.32%), limonene (1.35–59.68%), terpinen-4-ol (0.29–15.85%) and spathulenol (0.46–11.29%). Agglomerative Hierarchical Cluster analysis was conducted, showing the existence of two main groups. Obtained data for volatile components in each plant part gave an insight of the existence of simultaneous clear and large biodiversity of the chemical profiles of the studied plant parts.  相似文献   

8.
9.
The aim of the study was to compare BMI with waist circumference (WC), waist‐to‐hip ratio (WHR), and waist‐to‐stature ratio (WSR) as a predictor of diabetes incidence. A total of 1,841 men and 2,104 women of Mauritian Indian and Mauritian Creole ethnicity, aged 25–74 years, free of diabetes, hypertension, cardiovascular disease, and gout were seen at baseline in 1987 or 1992, and follow‐up in 1992 and/or 1998. At all time points, participants underwent a 2 h 75 g oral glucose tolerance test. Hazard ratios for diabetes incidence were estimated applying an interval‐censored survival analysis using age as timescale. Six hundred and twenty‐eight individuals developed diabetes during the follow‐up period. Multivariable adjusted hazard ratios for diabetes incidence corresponding to a 1 s.d. increase in baseline BMI, WC, WHR, and WSR for Mauritian Indians were 1.49 (1.31–1.71), 1.58 (1.38–1.81), 1.54 (1.37–1.72), and 1.61 (1.41–1.84) in men and 1.33 (1.17–1.51), 1.35 (1.19–1.53), 1.39 (1.24–1.55), and 1.38 (1.21–1.57) in women, respectively; and for Mauritian Creoles they were 1.86 (1.51–2.30), 2.07 (1.68–2.56), 1.92 (1.62–2.26), and 2.17 (1.76–2.69) in men and 1.29 (1.06–1.55), 1.27 (1.04–1.55), 1.24 (1.04–1.48), and 1.27 (1.04–1.55) in women. Paired homogeneity tests showed that there was no difference between BMI and each of the central obesity indicators (all P > 0.05). The relation of BMI with the development of diabetes was as strong as that for indicators of central obesity in this study population.  相似文献   

10.
Murraya koenigii (L.) Spreng. (Rutaceae), commonly known as ‘curry leaf tree’, is a popular spice and condiment of India. To explore the diversity of the essential‐oil yield and aroma profile of curry leaf, growing wild in foot and mid hills of north India, 58 populations were collected during spring season. M. koenigii populations were found to grow up to an altitude of 1487 m in north India. Comparative results showed considerable variations in the essential‐oil yield and composition. The essential‐oil yield varied from 0.14 to 0.80% in shade‐dried leaves of different populations of M. koenigii. Analysis of the essential oils by GC and GC/MS, and the subsequent classification by statistical analysis resulted in four clusters with significant variations in their terpenoid composition. Major components of the essential oils of investigated populations were α‐pinene ( 2 ; 4.5–71.5%), sabinene ( 3 ; <0.05–66.1%), (E)‐caryophyllene ( 11 ; 1.6–18.0%), β‐pinene ( 4 ; <0.05–13.6%), terpinen‐4‐ol ( 9 ; 0.0–8.4%), γ‐terpinene ( 8 ; 0.2–7.4%), limonene ( 7 ; 1.1–5.5%), α‐terpinene ( 6 ; 0.0–4.5%), (E)‐nerolidol ( 14 ; 0.0–4.1%), α‐humulene ( 12 ; 0.6–3.5%), α‐thujene ( 1 ; 0.0–2.5%), β‐elemene ( 10 ; 0.2–2.4%), β‐selinene ( 13 ; 0.2–2.3%), and myrcene ( 5 ; 0.5–2.1%). Comparison of the present results with those in earlier reports revealed new chemotypes of M. koenigii in investigated populations from Western Himalaya. The present study documents M. koenigii populations having higher amounts of sabinene ( 3 ; up to 66.1%) for the first time.  相似文献   

11.
12.
The variation of the essential‐oil composition among ten wild populations of Stachys lavandulifolia Vahl (Lamiaceae), collected from different geographical regions of Iran, was assessed by GC‐FID and GC/MS analyses, and their intraspecific chemical variability was determined. Altogether, 49 compounds were identified in the oils, and a relatively high variation in their contents was found. The major compounds of the essential oils were myrcene (0.0–26.2%), limonene (0.0–24.5%), germacrene D (4.2–19.3%), bicyclogermacrene (1.6–18.0%), δ‐cadinene (6.5–16.0%), pulegone (0.0–15.1%), (Z)‐hex‐3‐enyl tiglate (0.0–15.1%), (E)‐caryophyllene (0.0–12.9), α‐zingiberene (0.2–12.2%), and spathulenol (1.6–11.1%). For the determination of the chemotypes and the chemical variability, the essential‐oil components were subjected to cluster analysis (CA). The five different chemotypes characterized were Chemotype I (germacrene D/bicyclogermacrene), Chemotype II (germacrene D/spathulenol), Chemotype III (limonene/δ‐cadinene), Chemotype IV (pulegone), and Chemotype V (α‐zingiberene). The high chemical variation among the populations according to their geographical and bioclimatic distribution imposes that conservation strategies of populations should be made appropriately, taking into account these factors. The in situ and ex situ conservation strategies should concern all populations representing the different chemotypes.  相似文献   

13.

The milk oligosaccharides were studied for two species of the Carnivora: the American black bear (Ursus americanus, family Ursidae, Caniformia), and the cheetah, (Acinonyx jubatus, family Felidae, Feliformia). Lactose was the most dominant saccharide in cheetah milk, while this was a minor saccharide and milk oligosaccharides predominated over lactose in American black bear milk. The structures of 8 neutral saccharides from American black bear milk were found to be Gal(β1–4)Glc (lactose), Fuc(α1–2)Gal(β1–4)Glc (2′-fucosyllactose), Gal(α1–3)Gal(β1–4)Glc (isoglobotriose), Gal(α1–3)[Fuc(α1–2)]Gal(β1–4)Glc (B-tetrasaccharide), Gal(α1–3)[Fuc(α1–2)]Gal(β1–4)[Fuc(α1–3)]Glc (B-pentasaccharide), Fuc(α1–2)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc (difucosyl lacto-N-neotetraose), Gal(α1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–3)Gal(β1–4)Glc (monogalactosyl monofucosyl lacto-N-neotetraose) and Gal(α1–3)Gal(β1–4)GlcNAc(β1–3)Gal(β1–4)Glc (Galili pentasaccharide). Structures of 5 acidic saccharides were also identified in black bear milk: Neu5Ac(α2–3)Gal(β1–4)Glc (3′-sialyllactose), Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)[Fuc(α1–2)Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (monosialyl monofucosyl lacto-N-neohexaose), Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)[Gal(α1–3)Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (monosialyl monogalactosyl lacto-N-neohexaose), Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3){Gal(α1–3)Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–6)}Gal(β1–4)Glc (monosialyl monogalactosyl monofucosyl lacto-N-neohexaose), and Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3){Gal(α1–3)[Fuc(α1–2)]Gal(β1–4)[Fuc(α1–3)]GlcNAc(β1–6)}Gal(β1–4)Glc (monosialyl monogalactosyl difucosyl lacto-N-neohexaose). A notable feature of some of these milk oligosaccharides is the presence of B-antigen (Gal(α1–3)[Fuc(α1–2)]Gal), α-Gal epitope (Gal(α1–3)Gal(β1–4)Glc(NAc)) and Lewis x (Gal(β1–4)[Fuc(α1–3)]GlcNAc) structures within oligosaccharides. By comparison to American black bear milk, cheetah milk had a much smaller array of oligosaccharides. Two cheetah milks contained Gal(α1–3)Gal(β1–4)Glc (isoglobotriose), while another cheetah milk did not, but contained Gal(β1–6)Gal(β1–4)Glc (6′-galactosyllactose) and Gal(β1–3)Gal(β1–4)Glc (3′-galactosyllactose). Two cheetah milks contained Gal(β1–4)GlcNAc(β1–3)[Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (lacto-N-neohexaose), and one cheetah milk contained Gal(β1–4)Glc-3’-O-sulfate. Neu5Ac(α2–8)Neu5Ac(α2–3)Gal(β1–4)Glc (disialyllactose) was the only sialyl oligosaccharide identified in cheetah milk. The heterogeneity of milk oligosaccharides was found between both species with respect of the presence/absence of B-antigen and Lewis x. The variety of milk oligosaccharides was much greater in the American black bear than in the cheetah. The ratio of milk oligosaccharides-to-lactose was lower in cheetah (1:1–1:2) than American black bear (21:1) which is likely a reflection of the requirement for a dietary supply of N-acetyl neuraminic acid (sialic acid), in altricial ursids compared to more precocial felids, given the role of these oligosaccharides in the synthesis of brain gangliosides and the polysialic chains on neural cell adhesion.

  相似文献   

14.
Murdannia nampyana sp. nov. (Commelinaceae), collected from a marshy riparian area by the Kadambrayar River, near Bhramapuram Diesel Power Project, Kakkanad, Ernakulam district, Kerala is described. The new species can be distinguished from the similar species M. spirata G.Brückn. by its creeping habit, up to 1.5 m long with no definite base (vs erect, ascending, decumbent habit, with or without definite base), 1.1–2.2 cm wide flower diameter (vs 0.65–0.80 cm), petals 1.1 × 0.5–0.7 cm (vs 0.35–0.40 × 0.25–0.35 cm), 0.6–0.5–0.9 cm long stamen filaments (vs 0.06–0.15 cm), 0.20–0.25 cm long staminode filaments, (vs 0.06–0.15 cm), 2–3 smooth seeds per locule, with ridges and furrows and 1–2 small ventral depression on both side of the linear hilum and dorsal embryotega (vs 3–4 verrucose seeds per locule, with ridges and warts, 1–3 deep ventral pits on both side of elliptic hilum, edges of pits surrounded by warts, brownish powdery material in the testa and semidorsal embryotega).  相似文献   

15.
Choline acetyltransferase is critical in the synthesis of acetylcholine and regulation of cholinergic neuron functions. We recently reported association of the encoding gene ChAT with both smoking cessation and nicotine dependence (ND) in two independent European American (EA) samples; however, in the replication sample, only limited SNPs partially covering the gene were examined. In this study, we examined the association of 14 SNPs, which cover the entire gene, with ND, assessed by smoking quantity (SQ), heaviness of smoking index (HSI), and Fagerström Test for ND (FTND), in 2,037 subjects from 602 families of African American (AA) or EA origin. Individual SNP-based association analysis revealed that five SNPs showed nominal association with at least one ND measure in one of the samples (P = 0.022–0.042); none remained significant after correction for multiple testing. Haplotype-based association analysis revealed that haplotypes G–G–A–C, formed by rs1880676–rs3810950–rs10082479–rs8178990 (P = 0.005–0.0178), and G–G–T–C–G–C, formed by rs1880676–rs3810950–rs10082479–rs8178990–rs3793790–rs12266458 (P = 0.00247–0.00468), displayed significant association with all three ND measures in the AA sample, as did haplotype T–C–G–A–T, formed by rs12266458–rs11101191–rs8178991–rs4838544–rs4838547 (P = 0.00741–0.0103), in the EA sample. All these detected haplotype-based associations remained significant after correction for all major haplotypes for a given SNP combination. Together, our findings, in conjunction with the previous report of the association, warrant further investigation of ChAT in ND.  相似文献   

16.
An alkaloid (1), an amide (2), three lactones (3, 6 and 7), two coumarins (4–5), eight lignans (8–15), four alcohols (16–19) and three phenols (20–22) are obtained from the EtOAc soluble portion of the MeOH extract of the rhizome of Menispermum dauricum DC. The chemical structures of the compounds are determined by using spectroscopic methods and further supported by comparison with previous literatures. This is the first report that compounds 4–5, 12–17, 19 and 20–21 are obtained from the family Menispermaceae. Compounds 1–2, 6–11 and 22 are isolated for the first time from Menispermum genus. The chemotaxonomic significance of the compounds is also discussed.  相似文献   

17.
Hydrodistillated essential oils of Ziziphora clinopodioides ssp. rigida from nine populations of the Lashgardar protected region (Hamedan Province, Iran) were analyzed by using GC and GC/MS techniques to determine the intraspecific chemical variability. Altogether, 39 compounds were identified in the oils, and a relatively high variation in their contents was found. The main constituents of the essential oils were pulegone (0.7–44.5%), 1,8‐cineole (2.1–26.0%), neomenthol (2.5–22.5%), 4‐terpineol (0.0–9.9%), 1‐terpineol (0.0–13.2%), neomenthyl acetate (0.0–7.1%), and piperitenone (0.0–5.4%). For the determination of the chemotypes and the intraspecific chemical variability, the essential oil components were subjected to cluster analysis (CA). The five different chemotypes characterized were Chemotype I (pulegone/neomenthol), Chemotype II (pulegone), Chemotype III (pulegone/1,8‐cineole), Chemotype IV (neomenthol), and Chemotype V (1,8‐cineole/4‐terpineol).  相似文献   

18.
Infection by parasites has been studied in 189 specimens of Barbatula barbatula (Linnaeus, 1758) from eight rivers in Yaroslavl province over 4 years. A total of 41 parasite species are identified in stone loach. The following parasite taxa have been found: parasitic Protozoa (Kinetoplastidea (2), Myxozoa (6), and Ciliophora (7)) and parasitic Metazoa (Monogenea (5), Cestoda (4), Trematoda (9), Nematoda (4), Acanthocephala (3), and Bivalvia (1)). Stone loach is recorded for the first time as a new host for seven parasite species: Chloromyxum truttae Lèger, 1906, Gyrodactylus cobitis Bychowsky, 1933, Paracaryophylaeus gotoi (Motomura, 1927), Neogryporhynchus cheilancristrotus (Wedl, 1955), Paracoenogonimus ovatus Katsurada, 1914, Camallanus truncates (Rudolphi, 1814), and Neoechinorhynchus crassus Van Cleave, 1919. The most abundant parasites are Raphidascaris acus (Bloch, 1779) (28.6–100%, 1–64), Crepidostomum oschmarini Zhokhov et Pugacheva, 1998 (18.2–71.4%, 1–40), Paracoenogonimus ovatus (3.13–71.4% 1–34), and Gyrodactylus nemachili Bychowsky, 1936 (3.85–100%, 1–65).  相似文献   

19.
The present study is the first investigation of the volatile‐oil variability and insecticidal properties of the endemic Moroccan mint Mentha suaveolens subsp. timija (mint timija). The yield of essential oils (EOs) obtained from different wild mint timija populations ranged from 0.20±0.02 to 1.17±0.25% (v/w). GC/MS Analysis revealed the presence of 44 oil constituents, comprising 97.3–99.9% of the total oil compositions. The main constituents were found to be menthone (1.2–62.6%), pulegone (0.8–26.6%), cis‐piperitone epoxide (2.9–25.5%), piperitone (0.3–35.5%), trans‐piperitone epoxide (8.1–15.7%), piperitenone (0.2–9.6%), piperitenone oxide (0.5–28.6%), (E)‐caryophyllene (1.5–11.0%), germacrene D (1.0–15.7%), isomenthone (0.3–7.7%), and borneol (0.2–7.3%). Hierarchical‐cluster analysis allowed the classification of the EOs of the different mint timija populations into four main groups according to the contents of their major components. This variability within the species showed to be linked to the altitude variation of the mint timija growing sites. The results of the insecticidal tests showed that all samples exhibited interesting activity against adults of Tribolium castaneum, but with different degrees. The highest toxicity was observed for the EOs belonging to Group IV, which were rich in menthone and pulegone, with LC50 and LC90 values of 19.0–23.4 and 54.9–58.0 μl/l air in the fumigation assay and LC50 and LC90 values of 0.17–0.18 and 0.40–0.52 μl/cm2 in the contact assay.  相似文献   

20.
A study was carried out on 20 water bodies of the same origin in southern Poland. The study objectives included the assessment of toxic metal contamination in the bottom sediments of the water bodies in comparison with the geochemical background and sediments found in the substrate (i.e., vicinity) of the water bodies (i.e., the formations present in the surroundings of the water body itself), thus demonstrating the scale of anthropogenic enrichment of bottom sediments with toxic metals and assessing the cumulative impact on water bodies. The following amounts of toxic metals were found in the bottom sediments of the water bodies examined: 181.7–35200.0 ppm for zinc, 33.3–1648.8 ppm for lead, 1.8–359 ppm for cadmium, 14.0–271.5 ppm for copper, 45.3–167.5 ppm for chromium, and 12–128.5 ppm for nickel. Ratios of the values measured to the geochemical background were as follows: 0.7–135.9 (Zn), 0.6–53.0 (Pb), 0.7–143.6 (Cd), 0.9–18.1 (Cu), 5.0–18.6 (Cr), 1.1–11.7 (Ni).  相似文献   

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