Typhoons are becoming frequent and intense with ongoing climate change,threatening ecological security and healthy forest development in coastal areas.Eucalyptus of a predominant introduced species in southern China,f...Typhoons are becoming frequent and intense with ongoing climate change,threatening ecological security and healthy forest development in coastal areas.Eucalyptus of a predominant introduced species in southern China,faces significant growth challenges because of typhoon.Therefore,it is vital to investigate the variation of related traits and select superior breeding materials for genetic improvement.Variance,genetic parameter,and correlation analyses were carried out on wind damage indices and eight wood proper-ties in 88 families from 11 provenances of 10-year-old Euca-lyptus camaldulensis.The selection index equation was used for evaluating multiple traits and selecting superior prov-enances and family lines as future breeding material.The results show that all traits were highly significantly differ-ent at provenance and family levels,with the wind damage index having the highest coefficient of genetic variation.The heritability of each trait ranged from 0.48 to 0.87,with the wind damage index,lignin and hemicellulose contents,and microfibril angle having the highest heritabilities.The wind damage index had a positive genetic correlation with wood density,a negative correlation with lignin content,a negative phenotypic correlation and a negative genetic correlation with microfibril angle.Wind damage index and genetic progress in the selection of eight wood traits varied from 7.2%to 614.8%.Three provenances and 12 superior families were selected.The genetic gains of the wind damage index were 10.2%and 33.9%for provenances and families,and these may be starting material for genetic modification for wind resistance in eucalyptus and for their dissemination to typhoon-prone coastal areas of southern China.展开更多
Allelopathic effects of Eucalyptus camaldulensis Dehnh. were confirmed in Petri dish and pot experiments in our previous studies. However, the degree to which such effects under controlled experiments exist in more co...Allelopathic effects of Eucalyptus camaldulensis Dehnh. were confirmed in Petri dish and pot experiments in our previous studies. However, the degree to which such effects under controlled experiments exist in more complex ecological settings remains to be tested. Thus, the present study was carried out by incorporating different proportions of ground litter of E. camaldulensis in soil. The growth of three agricultural crops: falen(Vigna unguiculata(L.) Walp.), chickpea(Cicer arietinum L.), and arhor(Cajanus cajan(L.) Millsp.), and two tree species, kala koroi(Albizia procera(Roxb.) Benth.) and ipil ipil(Leucaena leucocephala(Lam.) de Wit) were tested. There were inhibitory effects of leaf litter on germination, shoot and root growth, leaf number, and collar diameter as well as a reduction of nodulation by legume crops(25–80%reduction). The extent of the effects was dependent on the proportion of leaf litter, the species and the type of traits. In contrast to shoot growth, the effect on root growth was more severe. No effect on germination was found with the agriculture crops while the two tree species showed reduced germination. The effect was greater in the presence of higher proportions of leaf litter mixed in soil while in some cases lower proportions stimulated growth. Not all species were suppressed; A. procera, C. cajan, V. unguiculata showed compatible growth while C. arietinum and L.leucocephala were found incompatible. This study provides evidence that E. camaldulensis has allelopathic potential under field conditions and a careful selection of associated crops in agroforestry systems is highly recommended.展开更多
Hardwoods are important raw material for making pulp and paper products. Eucalyptus camaldulensis is a fast-growing hardwood species with a wide distribution in Iran and can be introduced as appropriatematerial to com...Hardwoods are important raw material for making pulp and paper products. Eucalyptus camaldulensis is a fast-growing hardwood species with a wide distribution in Iran and can be introduced as appropriatematerial to compensate the wood shortages of the natural forest. Kraft pulping was performed under different cooking conditions and, based on the relations of pulp yield and kappa number, bleachable kraft pulp at screened yield of 43.3% and kappa number of 31.3 was selected for DED (Chlorine Dioxide-Alkaline Extraction-Chlorine Dioxide) bleaching and its bleachability was studied at different kappa factor in D~ stage. The results indicated that the bleachable kraft pulp from this species has high kappa number at acceptable screened yield and to complete the delignification in the bleaching process, higher kappa factor may be needed in DED bleaching sequence. The main reduction in final kappa number and yield loss were observed at kappa factor level of 0.2 but by further increase in kappa factor up to 0.4, more development were observed in optical properties but at lower opacity.展开更多
Particle size fractionation by sieving is used to optimize antioxydant potential of natural substances. The aim of the present study was to evaluate particle size effects on antioxidant and hepatoprotective potential ...Particle size fractionation by sieving is used to optimize antioxydant potential of natural substances. The aim of the present study was to evaluate particle size effects on antioxidant and hepatoprotective potential of Eucalyptus camaldulensis essential oils (EO) on CCl<sub>4</sub>-induced hepatic damage in Wistar rats. Animals were daily orally treated with the EOs extracted by hydrodistillation from powder sieved at four particle sizes (≥355, 200 - 355, 100 - 200, ≤100 μm) and those of the unsieved powder at dose of 50 mg/Kg for 7 days. Compounds that are evaluated for these activities are hydrocarbons and oxygenated terpenes that were identified and quantified by GC/MS. Activities of enzymes markers of hepatocellular damage in serum and antioxidant enzymes in the liver homogenates were measured. In this research, EOs significantly prevented the increase in serum ALT and AST (p < 0.05), total cholesterol, triglyceride and LDL-cholesterol level in acute liver damage induced by CCl<sub>4</sub> and significant increase level of plasma HDL-cholesterol. Also, significantly (p < 0.05) decreased the extent of malondialdehyde (MDA) formation and elevated the activities of superoxide dismutase (SOD) and catalase (CAT) liver in comparison to negative control group. The best antioxidant and hepatoprotective activities were those of EOs from two fine powder fractions (≤100 μm and 100 - 200 μm) was correlated to their high concentration in oxygenated terpenes (70.9% and 46.4%, respectively), when compared to the large particles (200 - 355 μm and ≥355 μm, with 33.3% and 41.8%, respectively) and unsieved powder (37.4%).展开更多
1,8-cineole, also known as eucalyptol, is the main constituent and the most important of the leaf oils of many species of the genus Eucalyptus. In present study, the essential oils isolated by hydrodistillation from t...1,8-cineole, also known as eucalyptol, is the main constituent and the most important of the leaf oils of many species of the genus Eucalyptus. In present study, the essential oils isolated by hydrodistillation from the leaves of Eucalyptus camaldulensis from six different locations were analyzed by GC-FID and GC-MS. Essential oil yields ranged from 0.33% to 4.35%. In total, 34 constituents were identified, accounting for 94.0% to 99.8% of the total compositions. 1,8-cineole (46.4% - 84.4%) was the main constituent of all the essential oil samples, except for one sample collected in the Fatick region, which had p-cymene (46.4%) and 1,8-cineole (26.0%) as major compounds. The essential oil showed excellent activity against S. aureus, E. coli and E. faecalis (IZ = 25.3 ± 1.2 mm;18.7 ± 0.6 mm;17.8 ± 0.3 mm, respectively) and moderate activity against P. aeruginosa (IZ = 10.8 ± 0.8 mm). They may have potential applications in food and pharmaceutical products.展开更多
Crude leaf extracts of Eucalyptus camaldulensis and Tylophora indica were evaluated for their antifeedancy against Helicoverpa armigera larvae in no-choice bioassays. Cabbage leaf-disc dipped in different concentratio...Crude leaf extracts of Eucalyptus camaldulensis and Tylophora indica were evaluated for their antifeedancy against Helicoverpa armigera larvae in no-choice bioassays. Cabbage leaf-disc dipped in different concentrations of leaf extracts was used for feeding fifth instars of H. armigera for 24 hours. Ethanol extracts from both the plant species exhibited significant feeding inhibition, activity. The effective concentrations of ethanol extracts that caused 50% reduction in larval feeding (EI50) were 6.9% for E. camaldulensis and 2.8% for T. indica, while these values of hexane extracts were 9.3% and 5.2%, respectively. Compared to the crude leaf extracts, crude alkaloids from T. indica and crude tannins from E. camaldulensis were more potent in reducing larval feedings.展开更多
Crude ethanolic extract of Eucalyptus camaldulensis was encapsulated with sodium alginate- sodium carboxymethyl cellulose (CMC) using freeze-drying techniques. The microcapsules were characterized for particle size, m...Crude ethanolic extract of Eucalyptus camaldulensis was encapsulated with sodium alginate- sodium carboxymethyl cellulose (CMC) using freeze-drying techniques. The microcapsules were characterized for particle size, morphology, physicochemical parameters, and micromeritics properties. Antioxidant and antimicrobial activities of the microcapsules were also demonstrated. Results revealed an irregular-shaped microparticles with a mean diameter ranging from 6.7 to 26.6 μm. Zeta potential and polydispersity index ranged from −17.01 to 2.23 mV and 0.34 to 0.49, respectively. Percentage yield ranged between 70.4 and 81.5 per cent whereas encapsulation efficiency ranged between 74.2 ± 0.011 and 82.43 ± 0.77 per cent. Swelling index and solubility varied inversely with extract concentration, with a range of 54.4%-84.0% and 18.8%-22.2%, respectively. Antioxidant activities varied directly with the concentration of the extract. Minimum inhibitory and minimum bactericidal concentrations of the microcapsules against Gram-positive foodborne pathogens ranged from 0.19 to 3.12 and 0.19-12.25 mg/ml, respectively. The Higuchi model indicated a time-dependent, delayed, and regulated release of polyphenols at 37°C. The results suggested that alginate-CMC possessed good encapsulant properties that preserved the bioactive extract, thus might be employed for application of natural products in food systems.展开更多
Objective:To evaluate the in vitro antimicrobial activities of the crude oil of Eucalyptus camaldulensis(E.camaldulensis)leaves.Methods:The essential oils of E.camaldulensis harvested from the garden of the Health Cen...Objective:To evaluate the in vitro antimicrobial activities of the crude oil of Eucalyptus camaldulensis(E.camaldulensis)leaves.Methods:The essential oils of E.camaldulensis harvested from the garden of the Health Center in Sidi Bel Abbes city(North West of Algeria),were screened for their antibacterial activities against two clinical bacteria[Escherichia coli(E.coli),Staphylococcus aureus(S.aureus)]by the agar disc diffusion method and broth dilution susceptibility assay.Results:The diameter of zones of inhibition by the leaf extracts of E.camaldulensis was 10-31 mm and 10-26 mm respectively for E.coli and S.aureus.Gram positive S.aureus was more resistant to tested essential oil than Gram negative E.coli.Conclusions:The results suggested a potential antimicrobial activity of the essential oil of E.camaldulensis,which may find its application in future research for the food and pharmaceutical industry.展开更多
The chemical composition of the essential oils obtained from the dried leaves of five species of the genus Eucalyptus (E. camaldulensis, E. de-glupta, E. grandis, E. torelliana, E. urophylla) growing in C?te d’Ivoire...The chemical composition of the essential oils obtained from the dried leaves of five species of the genus Eucalyptus (E. camaldulensis, E. de-glupta, E. grandis, E. torelliana, E. urophylla) growing in C?te d’Ivoire, was analyzed by means of GC and GC/MS. The density and the refractive index were measured. The major components of all these oils are: α-pinene, β-pinene, α-phellandrene, limonene, γ-terpinene, p-cymene and β-caryo-phyllene. The particularity of these oils is their monoterpene hydrocarbons major components.展开更多
Water is the most important limiting factor in the development of arid environments; therefore, optimization of water use is a necessity in desert reclamation projects. Evapotranspiration of a 6-year-old river red gum...Water is the most important limiting factor in the development of arid environments; therefore, optimization of water use is a necessity in desert reclamation projects. Evapotranspiration of a 6-year-old river red gum (Eucalyptus camaldulensis Dehnh.) plantation, located in a sedimentation basin of an artificial recharge of the Gareh Bygone Plain groundwater system in Iran's southern Zagros Mountains, was studied during a 7-month period. A neutron moisture probe was used to monitor soil water changes in the root zone. Soil water depletion following rapid drainage for blocks receiving relatively high, medium and low volumes of foodwater were 809.6, 312.4, and 203.1 mm, respectively, for a 150-day period. Soil water potential during most of the study period was below -1.5 MPa. This study proves that river red gum in not a suitable species for desertification control where water conservation is of vital importance. Flood irrigation of trees on 8 Aug. 1991 provided the opportunity to throw doubt upon the claim of summer dormancy of river red gum.展开更多
基金supported by the National Natural Science Foundation of China(Grant Number 32201527)National Key R&D Program of China(Grant No.2023YFD2201004).
文摘Typhoons are becoming frequent and intense with ongoing climate change,threatening ecological security and healthy forest development in coastal areas.Eucalyptus of a predominant introduced species in southern China,faces significant growth challenges because of typhoon.Therefore,it is vital to investigate the variation of related traits and select superior breeding materials for genetic improvement.Variance,genetic parameter,and correlation analyses were carried out on wind damage indices and eight wood proper-ties in 88 families from 11 provenances of 10-year-old Euca-lyptus camaldulensis.The selection index equation was used for evaluating multiple traits and selecting superior prov-enances and family lines as future breeding material.The results show that all traits were highly significantly differ-ent at provenance and family levels,with the wind damage index having the highest coefficient of genetic variation.The heritability of each trait ranged from 0.48 to 0.87,with the wind damage index,lignin and hemicellulose contents,and microfibril angle having the highest heritabilities.The wind damage index had a positive genetic correlation with wood density,a negative correlation with lignin content,a negative phenotypic correlation and a negative genetic correlation with microfibril angle.Wind damage index and genetic progress in the selection of eight wood traits varied from 7.2%to 614.8%.Three provenances and 12 superior families were selected.The genetic gains of the wind damage index were 10.2%and 33.9%for provenances and families,and these may be starting material for genetic modification for wind resistance in eucalyptus and for their dissemination to typhoon-prone coastal areas of southern China.
文摘Allelopathic effects of Eucalyptus camaldulensis Dehnh. were confirmed in Petri dish and pot experiments in our previous studies. However, the degree to which such effects under controlled experiments exist in more complex ecological settings remains to be tested. Thus, the present study was carried out by incorporating different proportions of ground litter of E. camaldulensis in soil. The growth of three agricultural crops: falen(Vigna unguiculata(L.) Walp.), chickpea(Cicer arietinum L.), and arhor(Cajanus cajan(L.) Millsp.), and two tree species, kala koroi(Albizia procera(Roxb.) Benth.) and ipil ipil(Leucaena leucocephala(Lam.) de Wit) were tested. There were inhibitory effects of leaf litter on germination, shoot and root growth, leaf number, and collar diameter as well as a reduction of nodulation by legume crops(25–80%reduction). The extent of the effects was dependent on the proportion of leaf litter, the species and the type of traits. In contrast to shoot growth, the effect on root growth was more severe. No effect on germination was found with the agriculture crops while the two tree species showed reduced germination. The effect was greater in the presence of higher proportions of leaf litter mixed in soil while in some cases lower proportions stimulated growth. Not all species were suppressed; A. procera, C. cajan, V. unguiculata showed compatible growth while C. arietinum and L.leucocephala were found incompatible. This study provides evidence that E. camaldulensis has allelopathic potential under field conditions and a careful selection of associated crops in agroforestry systems is highly recommended.
文摘Hardwoods are important raw material for making pulp and paper products. Eucalyptus camaldulensis is a fast-growing hardwood species with a wide distribution in Iran and can be introduced as appropriatematerial to compensate the wood shortages of the natural forest. Kraft pulping was performed under different cooking conditions and, based on the relations of pulp yield and kappa number, bleachable kraft pulp at screened yield of 43.3% and kappa number of 31.3 was selected for DED (Chlorine Dioxide-Alkaline Extraction-Chlorine Dioxide) bleaching and its bleachability was studied at different kappa factor in D~ stage. The results indicated that the bleachable kraft pulp from this species has high kappa number at acceptable screened yield and to complete the delignification in the bleaching process, higher kappa factor may be needed in DED bleaching sequence. The main reduction in final kappa number and yield loss were observed at kappa factor level of 0.2 but by further increase in kappa factor up to 0.4, more development were observed in optical properties but at lower opacity.
文摘Particle size fractionation by sieving is used to optimize antioxydant potential of natural substances. The aim of the present study was to evaluate particle size effects on antioxidant and hepatoprotective potential of Eucalyptus camaldulensis essential oils (EO) on CCl<sub>4</sub>-induced hepatic damage in Wistar rats. Animals were daily orally treated with the EOs extracted by hydrodistillation from powder sieved at four particle sizes (≥355, 200 - 355, 100 - 200, ≤100 μm) and those of the unsieved powder at dose of 50 mg/Kg for 7 days. Compounds that are evaluated for these activities are hydrocarbons and oxygenated terpenes that were identified and quantified by GC/MS. Activities of enzymes markers of hepatocellular damage in serum and antioxidant enzymes in the liver homogenates were measured. In this research, EOs significantly prevented the increase in serum ALT and AST (p < 0.05), total cholesterol, triglyceride and LDL-cholesterol level in acute liver damage induced by CCl<sub>4</sub> and significant increase level of plasma HDL-cholesterol. Also, significantly (p < 0.05) decreased the extent of malondialdehyde (MDA) formation and elevated the activities of superoxide dismutase (SOD) and catalase (CAT) liver in comparison to negative control group. The best antioxidant and hepatoprotective activities were those of EOs from two fine powder fractions (≤100 μm and 100 - 200 μm) was correlated to their high concentration in oxygenated terpenes (70.9% and 46.4%, respectively), when compared to the large particles (200 - 355 μm and ≥355 μm, with 33.3% and 41.8%, respectively) and unsieved powder (37.4%).
文摘1,8-cineole, also known as eucalyptol, is the main constituent and the most important of the leaf oils of many species of the genus Eucalyptus. In present study, the essential oils isolated by hydrodistillation from the leaves of Eucalyptus camaldulensis from six different locations were analyzed by GC-FID and GC-MS. Essential oil yields ranged from 0.33% to 4.35%. In total, 34 constituents were identified, accounting for 94.0% to 99.8% of the total compositions. 1,8-cineole (46.4% - 84.4%) was the main constituent of all the essential oil samples, except for one sample collected in the Fatick region, which had p-cymene (46.4%) and 1,8-cineole (26.0%) as major compounds. The essential oil showed excellent activity against S. aureus, E. coli and E. faecalis (IZ = 25.3 ± 1.2 mm;18.7 ± 0.6 mm;17.8 ± 0.3 mm, respectively) and moderate activity against P. aeruginosa (IZ = 10.8 ± 0.8 mm). They may have potential applications in food and pharmaceutical products.
文摘Crude leaf extracts of Eucalyptus camaldulensis and Tylophora indica were evaluated for their antifeedancy against Helicoverpa armigera larvae in no-choice bioassays. Cabbage leaf-disc dipped in different concentrations of leaf extracts was used for feeding fifth instars of H. armigera for 24 hours. Ethanol extracts from both the plant species exhibited significant feeding inhibition, activity. The effective concentrations of ethanol extracts that caused 50% reduction in larval feeding (EI50) were 6.9% for E. camaldulensis and 2.8% for T. indica, while these values of hexane extracts were 9.3% and 5.2%, respectively. Compared to the crude leaf extracts, crude alkaloids from T. indica and crude tannins from E. camaldulensis were more potent in reducing larval feedings.
基金This work was supported by Thailand’s Education Hub for ASEAN Countries(Grant No.TEH-AC 013/2017)the TRF Senior Research Scholar(Grant no.RTA 6180006)The Thailand Research Fund.
文摘Crude ethanolic extract of Eucalyptus camaldulensis was encapsulated with sodium alginate- sodium carboxymethyl cellulose (CMC) using freeze-drying techniques. The microcapsules were characterized for particle size, morphology, physicochemical parameters, and micromeritics properties. Antioxidant and antimicrobial activities of the microcapsules were also demonstrated. Results revealed an irregular-shaped microparticles with a mean diameter ranging from 6.7 to 26.6 μm. Zeta potential and polydispersity index ranged from −17.01 to 2.23 mV and 0.34 to 0.49, respectively. Percentage yield ranged between 70.4 and 81.5 per cent whereas encapsulation efficiency ranged between 74.2 ± 0.011 and 82.43 ± 0.77 per cent. Swelling index and solubility varied inversely with extract concentration, with a range of 54.4%-84.0% and 18.8%-22.2%, respectively. Antioxidant activities varied directly with the concentration of the extract. Minimum inhibitory and minimum bactericidal concentrations of the microcapsules against Gram-positive foodborne pathogens ranged from 0.19 to 3.12 and 0.19-12.25 mg/ml, respectively. The Higuchi model indicated a time-dependent, delayed, and regulated release of polyphenols at 37°C. The results suggested that alginate-CMC possessed good encapsulant properties that preserved the bioactive extract, thus might be employed for application of natural products in food systems.
基金Supported by Project(F03720120003)of Ministry of Higher Education&Scientific Research in Algeria.
文摘Objective:To evaluate the in vitro antimicrobial activities of the crude oil of Eucalyptus camaldulensis(E.camaldulensis)leaves.Methods:The essential oils of E.camaldulensis harvested from the garden of the Health Center in Sidi Bel Abbes city(North West of Algeria),were screened for their antibacterial activities against two clinical bacteria[Escherichia coli(E.coli),Staphylococcus aureus(S.aureus)]by the agar disc diffusion method and broth dilution susceptibility assay.Results:The diameter of zones of inhibition by the leaf extracts of E.camaldulensis was 10-31 mm and 10-26 mm respectively for E.coli and S.aureus.Gram positive S.aureus was more resistant to tested essential oil than Gram negative E.coli.Conclusions:The results suggested a potential antimicrobial activity of the essential oil of E.camaldulensis,which may find its application in future research for the food and pharmaceutical industry.
文摘The chemical composition of the essential oils obtained from the dried leaves of five species of the genus Eucalyptus (E. camaldulensis, E. de-glupta, E. grandis, E. torelliana, E. urophylla) growing in C?te d’Ivoire, was analyzed by means of GC and GC/MS. The density and the refractive index were measured. The major components of all these oils are: α-pinene, β-pinene, α-phellandrene, limonene, γ-terpinene, p-cymene and β-caryo-phyllene. The particularity of these oils is their monoterpene hydrocarbons major components.
文摘Water is the most important limiting factor in the development of arid environments; therefore, optimization of water use is a necessity in desert reclamation projects. Evapotranspiration of a 6-year-old river red gum (Eucalyptus camaldulensis Dehnh.) plantation, located in a sedimentation basin of an artificial recharge of the Gareh Bygone Plain groundwater system in Iran's southern Zagros Mountains, was studied during a 7-month period. A neutron moisture probe was used to monitor soil water changes in the root zone. Soil water depletion following rapid drainage for blocks receiving relatively high, medium and low volumes of foodwater were 809.6, 312.4, and 203.1 mm, respectively, for a 150-day period. Soil water potential during most of the study period was below -1.5 MPa. This study proves that river red gum in not a suitable species for desertification control where water conservation is of vital importance. Flood irrigation of trees on 8 Aug. 1991 provided the opportunity to throw doubt upon the claim of summer dormancy of river red gum.