Antibacterial and antifungal peptides found in houseflies （Musca domestica） in large number are indispensable components of its immune defense mechanism. In this study the anterior tip of the larvae of housefly was ...Antibacterial and antifungal peptides found in houseflies （Musca domestica） in large number are indispensable components of its immune defense mechanism. In this study the anterior tip of the larvae of housefly was cut off with a pair of fine scissors and hemolymph was collected and exuded in an ice-cold test tube. From the hemolymph an antifungal substance was isolated by solid-phase extraction combined with reverse phase-high performance liquid chromotography （RP-HPLC） and named as Musca domestica antifungal peptide-1 （MAF-1）. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis （SDS-PAGE） showed its molecular weight was 17 kDa. UV absorption spectra revealed that this antifungal substance possessed the characteristics of protein peptides. Analysis by fingerprint-identification and tandem mass spectrometry suggested MAF-I was an unknown protein. Edman degradation identified the sequence of 30 amino acids of its N-terminal which matched no peptide in the MASCOT search database, indicating MAF-1 was a novel insect antifungal peptide. Mass spectrometry showed the precise molecular weight of MAF-1 was 17203.384 Da. Its isoelectric point was acidic.展开更多
Lysozymes can hydrolyze bacteria and play an important role in animal digestion and innate immunity. The cDNA of a chicken-type lysozyme gene （Mdlys） was cloned from housefly （Musca domestica）. The 484 bp full-len...Lysozymes can hydrolyze bacteria and play an important role in animal digestion and innate immunity. The cDNA of a chicken-type lysozyme gene （Mdlys） was cloned from housefly （Musca domestica）. The 484 bp full-length cDNA contains a 426 bp open reading frame （ORF） that encodes MdLys of 141 amino acids. Phylogenetic analysis indicated that the MdLys was similar to chicken-type lysozymes. Spatio-temporal expression of Mdlys was analyzed by RT-PCR. The Mdlys transcript can be detected in both midgut and fat body and was expressed at a relatively lower level at the embryo stage. Mdlys mRNA was upregulated 2 h post bacterial challenge, maintained for 2 to 6 h, and slightly declined from 12 to 24 h post-injection. Western blot analysis showed that MdLys was highly expressed in midgut and was also detected in the hemolymph and fat body. MdLys expression was slightly increased in midgut after challenging with Escherichia coli or Staphylococcus aureus. Its expression was also slightly increased in the fat body after challenging with S. aureus, but no obvious change occurred after E. coli challenge. MdLys expression in the hemolymph was not affected by bacterial challenge. In the developmental stages, MdLys expression levels had no obvious change from the first instar to the pupae stage. There was also no variation under 24 h starvation stress. Recombinant MdLys displayed inhibitory activity against Gram-negative and Gram-positive bacteria. Together, these results suggest that MdLys may play an important role in the innate immunity of houseflies.展开更多
Objective:To investigate the effect of utilizing a molecular partner on high-level expression of Mxisca domestica(M.domestica) cecropin in Escherichia coli(E.coli) and to identify the expressed products.Methods:The ge...Objective:To investigate the effect of utilizing a molecular partner on high-level expression of Mxisca domestica(M.domestica) cecropin in Escherichia coli(E.coli) and to identify the expressed products.Methods:The genomic sequence of M.domestica cecropin A(MC) and M. domestica ubiquitin(UBI) were searched from Cenbank and amplified by reverse transcriptase polymerase chain reaction(RT-PCR).Two expression plasmids,pET32a-MC and pET32a-UBI-MC, were constructed and transferred into E.coli and were then induced by Isopropylβ-D-1- Thiogalactopyranoside(IPTG).The expression of the fusion proteins Trx-MC and Trx-UBI-MC was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE).Fusion protein Trx-MC was verified by Western blot analysis.The bactericidal activity of the purified MC was quantitatively determined using E.coli BL21(DE3).Results:The result showed that the fusion proteins were successively expressed in E.coli BL21 cells.A band at the expected position of 24 kDa representing the Trx-MC target protein was positivelystained,and the band at 4 kDa representing the hydrolysis of mature MC protein was also observed at the expected position. The expression levels of Trx-UBI-MC were higher than that of Trx-MC in E.coli.MC exhibited antimicrobial activity.Conclusions:With high-level expression of housefly cecropin A in E.coli using a fusion protein,MC exhibited antimicrobial activity.展开更多
With environmental and food safety issues becoming one of the greatest concerns of the public, active plant compounds play more and more important roles in pest controlling. Fern to their particular status in plant ta...With environmental and food safety issues becoming one of the greatest concerns of the public, active plant compounds play more and more important roles in pest controlling. Fern to their particular status in plant taxology and co-evolution are of great significance for application as new pesticides due with insects. In this study, methanol extracts were distilled from wild fern and gymnosperm of 54 species of 22 families collected from Shiwandashan Mountain in Guangxi Zhuang Autonomous Region of China. Insecticidal activities of the methanol extracts were assayed on both adult house fly （Musca domestica） and mosquito （Aedes albopictus）. Significant insecticidal activities were exhibited in the methanol extracts of five species, Cupressusfunebris （leaves and stems）, Cycas acuminatissima （roots）, Keteleeria fortunei （leaves and stems）, Onychium japonicum （whole plant）, and Pinus taiwanensis var. Darning shanensis （leaves and stems）. Applications of the extracts of these plants resulted in higher than 50% mortalities in 4th instar larvae of A. albopictus at 24 h after treatment. The methanol extracts from 13 species possessed insecticidal activities against the adult of M. domestica at 48 h after treatment with higher than 90% mortalities. The extensive screening results showed that these fern and gymnosperm were highly potential to be botanical insecticides. The findings provide a feasible and valuable basis for further investigation.展开更多
Background: The occurrence of bacterial infections sometimes involves synanthropic flies and cockroaches, as mechanical vectors of pathogenic microorganisms. The aim of this study was to identify the different species...Background: The occurrence of bacterial infections sometimes involves synanthropic flies and cockroaches, as mechanical vectors of pathogenic microorganisms. The aim of this study was to identify the different species of flies and cockroaches that cohabit with humans in the city of Cotonou and determine the contribution of Musca domestica and Periplaneta americana in the transmission of bacteria responsible for infections in humans. Methods: Capture sessions during the day for flies and at night for cockroaches were carried out in 4 arrondissements of the city of Cotonou. The insects collected were transported to the Center of Research Entomological of Cotonou for identification, then sent to the Section Hygiene of Water and Food for microbiological analysis, enumeration and testing for human pathogenic bacteria. Results: A total of 351 flies and 26 cockroaches were collected at the sites, including two synanthropic species belonging to two families each. Musca domestica and Periplaneta americana were the most abundant species found after identification in the city of Cotonou. Thermo-tolerant coliforms and Escherichia coli were found on all specimens at varying concentrations. Salmonella spp. bacteria were identified in the fly population from the Dantokpa dump. Conclusion: Flies and cockroaches can transmit microorganisms to humans. The presence of Salmonella spp. among the specimens revealed that infections frequently caused by contaminated food or water are also transmitted to humans by flies. The presence of these germs on flies and cockroaches represents a potential risk of mechanical transmission to humans. It is, therefore, essential to continue investigations in order to assess the species of bacteria propagated, improve control strategies against these troublesome insects and adopt better hygiene conditions for better living.展开更多
The inhibition effect of chitooligosaccharides from housefly larvae on pathogens ofcrops seeds, fruits or vegetables was studied and the main factors influencing theantimicrobial activity of chitooligosaccharides were...The inhibition effect of chitooligosaccharides from housefly larvae on pathogens ofcrops seeds, fruits or vegetables was studied and the main factors influencing theantimicrobial activity of chitooligosaccharides were also investigated. It was foundthat chitooligosaccharides from housefly larvae had wide spectrum fungistasis. It canstrongly inhibit the development of 31 kinds of plant pathogenic fungi such as corticiumrolfsii Saccardo. The results indicated that the degree of deacelylation (DD) or theaverage molecular weight(MW)of chitooligosaccharides were related to the antimicrobialactivity. The antimicrobial activity increased with the rising of DD or the declining ofMW. Pot culture results showed that chitooligosaccharide could enhance the rate ofgermination and emergence of the seeds of maize, wheat and cotton. Chitooligosaccharidehad certain effect on corn southern leaf blight caused by Helminthosporium maydis.展开更多
The significant increase in the demand for biomass waste treatment after garbage classification has led to housefly larvae treatment becoming an attractive treatment option.It can provide a source of protein while tre...The significant increase in the demand for biomass waste treatment after garbage classification has led to housefly larvae treatment becoming an attractive treatment option.It can provide a source of protein while treating biomass waste,which means that nutrients can be returned to the natural food chain.However,the performance of this technology in terms of its environmental impacts is still unclear,particularly with regards to global warming potential(GWP).This study used a life cycle assessment(LCA)approach to assess a housefly larvae treatment plant with a treatment capacity of 50 tons of biomass waste per day.The LCA results showed that the 95% confidence intervals for the GWP in summer and winter were determined to be 24.46-32.81 kg CO_(2) equivalent(CO_(2)-eq)/ton biomass waste and5.37-10.08 kg CO_(2)-eq/ton biomass waste,respectively.The greater GWP value in summer is due to the longer ventilation time and higher ventilation intensity in summer,which consumes more power.The main GWP contributions are from(1)electricity needs(accounting for 78.6% of emissions in summer and 70.2%in winter)and(2)product substitution by mature housefly larvae and compost(both summer and winter accounting for 96.8% of carbon reduction).展开更多
Insecticidal activities of the petroleum ether-, chloroform-, ethyl acetate-, and water-soluble fractions of the methanolic extract ofFicus sarmentosa var. henryi were assayed against Musca domestica adults. The chlor...Insecticidal activities of the petroleum ether-, chloroform-, ethyl acetate-, and water-soluble fractions of the methanolic extract ofFicus sarmentosa var. henryi were assayed against Musca domestica adults. The chloroform- and ethyl acetate- soluble fractions were the most active with 92.6 and 88.9% mortalities （24 h after treatment） respectively. Therefore, the two fractions were combined and four compounds, isolated from the fractions by activity-guided fractionation, were elucidated as 7-hydroxycoumarin, apigenin, eriodictyol, and quercetin by spectroscopic method and displayed excellent insecticidal activities against adults of M. domestica and 4th instar larva of Aedes albopictus. Among those, 7- hydroxycoumarin showed the strongest insecticidal activities with lethal concentrations （LC50） values of 72.13 μg g^-1 sugar and 4.87 μg mL^-1 （48 h after treatment） against the test insects respectively. The cytoxicities of these compounds on BTI-Tn-5B 1-4 cell were also investigated for the insecticidal mechanism and found that quercetin represented superior inhibitory activity with MTT assay and reactive oxygen species （ROS） against BTI-Tn-5B 1-4 cell, but slightly weaker than that of the positive control （azadirachtin） and significantly greater than the negative control （DMSO only）. Meanwhile, eriodictyol demonstrated the strongest effect on the mitochondrial membrane potentials （MMP）. In conclusion, based on their comparative toxicities to commercial insecticides and their cytotoxic effects, some of the compounds from the F. sarmentosa have potential as botanical insecticides.展开更多
Objective To better comprehend the molecular structure and physiological function of the housefly larval peritrophic matrix （PM）, a mass spectrometry approach was used to investigate the PM protein composition. Meth...Objective To better comprehend the molecular structure and physiological function of the housefly larval peritrophic matrix （PM）, a mass spectrometry approach was used to investigate the PM protein composition. Methods The PM was dissected from the midgut of the third instar larvae, and protein extracted from the PM was evaluated using SDS-PAGE. A 1D-PAGE lane containing all protein bands was cut from top to bottom, the proteins in-gel trypsinised and analysed via shotgun liquid chromatography- tandem mass spectrometry （LC-MS/MS）. Results In total, 374 proteins, with molecular weights varying from 8.225, kD to 996.065 kD and isoelectric points ranging from 3.83 to 11.24 were successfully identified, most identified proteins were mainly related to immunity, digestion, nutrient metabolism and PM structure. Furthermore, many of these proteins were functionally associated with pattern binding, polysaccharide binding, structural constituent of peritrophic membrane and chitin binding, according to Gene Ontology annotation. Conclusion The PM protein composition, which provides a basis for further functional investigations of the identified proteins, will be useful for understanding the housefly larval gut immune system and may help to identify potential targets and exploit new bioinsecticides.展开更多
This work studied the transcriptional patterns of three antibacterial genes,attacin,defensin and cecropin,during the development of Musca domestica. Quantitative analysis by real-time PCR was performed on mRNA levels ...This work studied the transcriptional patterns of three antibacterial genes,attacin,defensin and cecropin,during the development of Musca domestica. Quantitative analysis by real-time PCR was performed on mRNA levels in different development stages and challenged 3rd-instar larva at different time points after challenge of Musca domestica. The results revealed a predominance of the transcripts of all three genes during the 3rd-instar larvae and the adults. In the meanwhile,it revealed the greatest increase in mRNA. The transcript levels increased to 801 times,1009 times and 2500 times respectively for cecropin,attacin and defensin in 3rd-instar larvae after challenging susceptible bacterium. The results suggested that the transcriptional patterns of Musca domestica antibacterial genes were different during the different growth stages as well as the microbial challenge encountered in 3rd-instar larvae.展开更多
[Objective] The research aimed to observe the effects of Escherichia coli infection on the morphology of hemocytes of the 3rd stage larva of Musca domestica in vitro and understand the hemocytes types that take part i...[Objective] The research aimed to observe the effects of Escherichia coli infection on the morphology of hemocytes of the 3rd stage larva of Musca domestica in vitro and understand the hemocytes types that take part in the cell immunity of Musca domestica larval.[Method] The hemcytes of the 3rd stage larva of Musca domestica were cultured in vitro and the hemocyte morphology was observed about 2,4,6,8 h after culture in vitro.After Escherichia coli were injected into the hemocytes of the 3rd stage larva of Musca domestica in vitro,the morphology changes of hemocytes were observed at different time after infection.[Result] The hemocytes of of the 3rd stage larva of Musca domestica was divided into five types about 2 h after hemoculture.The hemocytes partly adherence was seen about 6 h after hemoculture.The vacuolation and morpholysis was found in plasmatocytes after being infected by E.coli and a great quantity bacterium were gathered around granulocyte,but the morphology changes of hemocytes were not found in the prohemocyte,shprulocyte and oenocytoid.[Conclusion] The plasmatocyte and granulocyte were primary participants of the cell immunity of Musca domestica larval,but the prohemocyte,sphrulocyte and oenocytoid do not participate in the cell immune reactions.展开更多
Amaranth is one of the most consumed vegetables in Niger Republic because of its nutritional values. However, the production of this plant requires nutrient-rich soils that are becoming scarce in most agricultural soi...Amaranth is one of the most consumed vegetables in Niger Republic because of its nutritional values. However, the production of this plant requires nutrient-rich soils that are becoming scarce in most agricultural soils in Niger. This study aims to evaluate the fertilizing potential of the maggot production residue of Musca domestica L. 1758 and bovine excrement on the agronomic parameters of Amaranthus cruentus L., 1759. To do this, four densities (50, 100, 150, 200 g) of maggot production residue and bovine excrement were tested. Stem length, neck diameter and leaf number were strongly influenced by the interaction of the type of treatment (maggot production residue and bovine excrement) and dose. Dose 50 and dose 150 gave the best performance in length and diameter respectively for residue (length = 42.24 ± 8.98 cm;diameter = 0.88 ± 0.17 cm) and bovine droppings (length = 39.29 ± 8.10;diameter = 0.98 ± 0.77). On the leaf number side, no significant differences were observed between the doses for the residue. For bovine excrement, this number was higher at the 150 g dose (28.12 ± 4.98). The effect of the residue and bovine excrement on each corresponding dose shows that, for the stem length, only the 50 g dose was statistically influenced by the latter (P < 0.001). On the neck diameter side, only the 50 g and 100 g doses were statistically influenced by bovine residue and excrement (dose 50 g: P < 0.001;dose 100 g: P < 0.001). For each of these doses, the residue recorded the best performance both for the length of the rod and for the diameter at the collar. On the leaf number side, only the dose 50 g and 150 g varied statistically according to the type of fertilizer. At the 50 g dose, the residue recorded the largest number of leaves (27.10 ± 11.15), but the residue recorded the lowest number of leaves at the 100 g dose (21.01 ± 5.99). Foliar and root biomass varied statistically according to the dose within each fertilizer (foliar biomass: residue: P = 0.040;bovine excrement: P < 0.001;root biomass: re展开更多
The ＂fly factor＂ was first discovered 〉60 years ago and describes the phe- nomenon that food currently or previously fed on by flies attracts more foraging flies than the same type and amount of food kept inaccessi...The ＂fly factor＂ was first discovered 〉60 years ago and describes the phe- nomenon that food currently or previously fed on by flies attracts more foraging flies than the same type and amount of food kept inaccessible to flies. Since then, there has been little progress made to understanding this phenomenon. Our objectives were （i） to demonstrate the existence of the fly factor in house flies, Musca domestica and （ii） to study underlying mechanisms that may cause or contribute to the fly factor. In 2-choice laboratory bioassays, we obtained unambiguous evidence for a fly factor phenomenon in house flies, in that we demonstrated that feeding flies are more attractive to foraging flies than are nonfeeding flies, and that fed-on food is more attractive to foraging flies than is ＂clean＂ food. Of the potential mechanisms （fly excreta, metabolic output parameters [elevated temperature, relative humidity, carbon dioxide]）, causing the fly factor, fly feces, and regurgitate do at- tract foraging flies but none of the metabolic output parameters of feeding flies does. Even though feeding flies produce significantly more CO2 than nonfeeding flies, elevated levels of CO2 have no behavior-modifying effect on flies. Preferential attraction of house flies to fly feces and regurgitate indicates that the flies sense airborne semiochemicals emana- ting from these sources. Hypothesizing that these semiochemicals are microbe-produced, future studies will aim at isolating and mass producing these microbes to accumulate semiochemicals for identification.展开更多
The house fly, Musca domestica, has been implicated as a vector of Campy- lobacter spp., a major cause of human disease. Little is known whether house flies serve as biological amplifying hosts or mechanical vectors f...The house fly, Musca domestica, has been implicated as a vector of Campy- lobacter spp., a major cause of human disease. Little is known whether house flies serve as biological amplifying hosts or mechanical vectors for Campylobacterjejuni. We in- vestigated the period after C. jejuni had been ingested by house flies in which viable C. jejuni colonies could be isolated from whole bodies, the vomitus and the excreta of adult M. domestica and evaluated the activation of innate immune responses of house flies to ingested C. jejuni over time. C. jejuni could be cultured from infected houseflies soon after ingestion but no countable C. jejuni colonies were observed 〉 24 h postingestion. We detected viable C. jejuni in house fly vomitus and excreta up to 4 h after ingestion, but no viable bacteria were detected 〉 8 h. Suppression subtractive hybridization identi- fied pathogen-induced gene expression in the intestinal tracts of adult house flies 4-24 h after ingesting C. jejuni. We measured the expression of immune regulatory （thor, JNK, and spheroide） and effector （cecropin, diptericin, attacin, defensing, and lysozyme） genes in C. jejuni-infected and -uninfected house flies using quantitative real time PCR. Some house fly factor, or combination of factors, eliminates C. jejuni within 24 h postingestion. Because C. jejuni is not amplified within the body of the housefly, this insect likely serves as a mechanical vector rather than as a true biological, amplifying vector for C. jejuni, and adds to our understanding of insect pathogen interactions.展开更多
基金Acknowledgements This work was supported by grants from the National Natural Science Foundation of China （No. 39970087）, the Special Fund of Governor of Guizhou Province [QKJB（2003）04], and ＂Western Lights＂ of Chinese Academy of Sciences [KJWZ（2005）404].
文摘Antibacterial and antifungal peptides found in houseflies （Musca domestica） in large number are indispensable components of its immune defense mechanism. In this study the anterior tip of the larvae of housefly was cut off with a pair of fine scissors and hemolymph was collected and exuded in an ice-cold test tube. From the hemolymph an antifungal substance was isolated by solid-phase extraction combined with reverse phase-high performance liquid chromotography （RP-HPLC） and named as Musca domestica antifungal peptide-1 （MAF-1）. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis （SDS-PAGE） showed its molecular weight was 17 kDa. UV absorption spectra revealed that this antifungal substance possessed the characteristics of protein peptides. Analysis by fingerprint-identification and tandem mass spectrometry suggested MAF-I was an unknown protein. Edman degradation identified the sequence of 30 amino acids of its N-terminal which matched no peptide in the MASCOT search database, indicating MAF-1 was a novel insect antifungal peptide. Mass spectrometry showed the precise molecular weight of MAF-1 was 17203.384 Da. Its isoelectric point was acidic.
基金supported by the National High Technology Research and Development Program of China (863 Program) (No. 2007AA09Z425 and 2006AA100311)the Ph.D. Program Foundation of the Ministry of Education of China (No. 20060422034).
文摘Lysozymes can hydrolyze bacteria and play an important role in animal digestion and innate immunity. The cDNA of a chicken-type lysozyme gene （Mdlys） was cloned from housefly （Musca domestica）. The 484 bp full-length cDNA contains a 426 bp open reading frame （ORF） that encodes MdLys of 141 amino acids. Phylogenetic analysis indicated that the MdLys was similar to chicken-type lysozymes. Spatio-temporal expression of Mdlys was analyzed by RT-PCR. The Mdlys transcript can be detected in both midgut and fat body and was expressed at a relatively lower level at the embryo stage. Mdlys mRNA was upregulated 2 h post bacterial challenge, maintained for 2 to 6 h, and slightly declined from 12 to 24 h post-injection. Western blot analysis showed that MdLys was highly expressed in midgut and was also detected in the hemolymph and fat body. MdLys expression was slightly increased in midgut after challenging with Escherichia coli or Staphylococcus aureus. Its expression was also slightly increased in the fat body after challenging with S. aureus, but no obvious change occurred after E. coli challenge. MdLys expression in the hemolymph was not affected by bacterial challenge. In the developmental stages, MdLys expression levels had no obvious change from the first instar to the pupae stage. There was also no variation under 24 h starvation stress. Recombinant MdLys displayed inhibitory activity against Gram-negative and Gram-positive bacteria. Together, these results suggest that MdLys may play an important role in the innate immunity of houseflies.
基金supported by grants from National Natural Science Foundation of China(No.30972566,3087198)
文摘Objective:To investigate the effect of utilizing a molecular partner on high-level expression of Mxisca domestica(M.domestica) cecropin in Escherichia coli(E.coli) and to identify the expressed products.Methods:The genomic sequence of M.domestica cecropin A(MC) and M. domestica ubiquitin(UBI) were searched from Cenbank and amplified by reverse transcriptase polymerase chain reaction(RT-PCR).Two expression plasmids,pET32a-MC and pET32a-UBI-MC, were constructed and transferred into E.coli and were then induced by Isopropylβ-D-1- Thiogalactopyranoside(IPTG).The expression of the fusion proteins Trx-MC and Trx-UBI-MC was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE).Fusion protein Trx-MC was verified by Western blot analysis.The bactericidal activity of the purified MC was quantitatively determined using E.coli BL21(DE3).Results:The result showed that the fusion proteins were successively expressed in E.coli BL21 cells.A band at the expected position of 24 kDa representing the Trx-MC target protein was positivelystained,and the band at 4 kDa representing the hydrolysis of mature MC protein was also observed at the expected position. The expression levels of Trx-UBI-MC were higher than that of Trx-MC in E.coli.MC exhibited antimicrobial activity.Conclusions:With high-level expression of housefly cecropin A in E.coli using a fusion protein,MC exhibited antimicrobial activity.
基金funded by the National Nature Science Foundation of China (30571235)the Industry Schemes of the Ministry of Agriculture,China(200903052)
文摘With environmental and food safety issues becoming one of the greatest concerns of the public, active plant compounds play more and more important roles in pest controlling. Fern to their particular status in plant taxology and co-evolution are of great significance for application as new pesticides due with insects. In this study, methanol extracts were distilled from wild fern and gymnosperm of 54 species of 22 families collected from Shiwandashan Mountain in Guangxi Zhuang Autonomous Region of China. Insecticidal activities of the methanol extracts were assayed on both adult house fly （Musca domestica） and mosquito （Aedes albopictus）. Significant insecticidal activities were exhibited in the methanol extracts of five species, Cupressusfunebris （leaves and stems）, Cycas acuminatissima （roots）, Keteleeria fortunei （leaves and stems）, Onychium japonicum （whole plant）, and Pinus taiwanensis var. Darning shanensis （leaves and stems）. Applications of the extracts of these plants resulted in higher than 50% mortalities in 4th instar larvae of A. albopictus at 24 h after treatment. The methanol extracts from 13 species possessed insecticidal activities against the adult of M. domestica at 48 h after treatment with higher than 90% mortalities. The extensive screening results showed that these fern and gymnosperm were highly potential to be botanical insecticides. The findings provide a feasible and valuable basis for further investigation.
文摘Background: The occurrence of bacterial infections sometimes involves synanthropic flies and cockroaches, as mechanical vectors of pathogenic microorganisms. The aim of this study was to identify the different species of flies and cockroaches that cohabit with humans in the city of Cotonou and determine the contribution of Musca domestica and Periplaneta americana in the transmission of bacteria responsible for infections in humans. Methods: Capture sessions during the day for flies and at night for cockroaches were carried out in 4 arrondissements of the city of Cotonou. The insects collected were transported to the Center of Research Entomological of Cotonou for identification, then sent to the Section Hygiene of Water and Food for microbiological analysis, enumeration and testing for human pathogenic bacteria. Results: A total of 351 flies and 26 cockroaches were collected at the sites, including two synanthropic species belonging to two families each. Musca domestica and Periplaneta americana were the most abundant species found after identification in the city of Cotonou. Thermo-tolerant coliforms and Escherichia coli were found on all specimens at varying concentrations. Salmonella spp. bacteria were identified in the fly population from the Dantokpa dump. Conclusion: Flies and cockroaches can transmit microorganisms to humans. The presence of Salmonella spp. among the specimens revealed that infections frequently caused by contaminated food or water are also transmitted to humans by flies. The presence of these germs on flies and cockroaches represents a potential risk of mechanical transmission to humans. It is, therefore, essential to continue investigations in order to assess the species of bacteria propagated, improve control strategies against these troublesome insects and adopt better hygiene conditions for better living.
文摘The inhibition effect of chitooligosaccharides from housefly larvae on pathogens ofcrops seeds, fruits or vegetables was studied and the main factors influencing theantimicrobial activity of chitooligosaccharides were also investigated. It was foundthat chitooligosaccharides from housefly larvae had wide spectrum fungistasis. It canstrongly inhibit the development of 31 kinds of plant pathogenic fungi such as corticiumrolfsii Saccardo. The results indicated that the degree of deacelylation (DD) or theaverage molecular weight(MW)of chitooligosaccharides were related to the antimicrobialactivity. The antimicrobial activity increased with the rising of DD or the declining ofMW. Pot culture results showed that chitooligosaccharide could enhance the rate ofgermination and emergence of the seeds of maize, wheat and cotton. Chitooligosaccharidehad certain effect on corn southern leaf blight caused by Helminthosporium maydis.
基金supported by the National Key Research and Development Program of China(No.2018YFD1100600)Shanghai Municipal Government State-Owned Assets Supervision and Administration Commission(No.2022028)。
文摘The significant increase in the demand for biomass waste treatment after garbage classification has led to housefly larvae treatment becoming an attractive treatment option.It can provide a source of protein while treating biomass waste,which means that nutrients can be returned to the natural food chain.However,the performance of this technology in terms of its environmental impacts is still unclear,particularly with regards to global warming potential(GWP).This study used a life cycle assessment(LCA)approach to assess a housefly larvae treatment plant with a treatment capacity of 50 tons of biomass waste per day.The LCA results showed that the 95% confidence intervals for the GWP in summer and winter were determined to be 24.46-32.81 kg CO_(2) equivalent(CO_(2)-eq)/ton biomass waste and5.37-10.08 kg CO_(2)-eq/ton biomass waste,respectively.The greater GWP value in summer is due to the longer ventilation time and higher ventilation intensity in summer,which consumes more power.The main GWP contributions are from(1)electricity needs(accounting for 78.6% of emissions in summer and 70.2%in winter)and(2)product substitution by mature housefly larvae and compost(both summer and winter accounting for 96.8% of carbon reduction).
基金support by the National Natural Science Foundation of China (30571235)
文摘Insecticidal activities of the petroleum ether-, chloroform-, ethyl acetate-, and water-soluble fractions of the methanolic extract ofFicus sarmentosa var. henryi were assayed against Musca domestica adults. The chloroform- and ethyl acetate- soluble fractions were the most active with 92.6 and 88.9% mortalities （24 h after treatment） respectively. Therefore, the two fractions were combined and four compounds, isolated from the fractions by activity-guided fractionation, were elucidated as 7-hydroxycoumarin, apigenin, eriodictyol, and quercetin by spectroscopic method and displayed excellent insecticidal activities against adults of M. domestica and 4th instar larva of Aedes albopictus. Among those, 7- hydroxycoumarin showed the strongest insecticidal activities with lethal concentrations （LC50） values of 72.13 μg g^-1 sugar and 4.87 μg mL^-1 （48 h after treatment） against the test insects respectively. The cytoxicities of these compounds on BTI-Tn-5B 1-4 cell were also investigated for the insecticidal mechanism and found that quercetin represented superior inhibitory activity with MTT assay and reactive oxygen species （ROS） against BTI-Tn-5B 1-4 cell, but slightly weaker than that of the positive control （azadirachtin） and significantly greater than the negative control （DMSO only）. Meanwhile, eriodictyol demonstrated the strongest effect on the mitochondrial membrane potentials （MMP）. In conclusion, based on their comparative toxicities to commercial insecticides and their cytotoxic effects, some of the compounds from the F. sarmentosa have potential as botanical insecticides.
基金supported by National Natural Science Foundation of China(No.81360254)National Sci-Tech Support Plan of China under grant(No.2011BAC06B12)the Science and Technology Program of Guizhou Province Agricultural research Project[No.NY(2014)3054]
文摘Objective To better comprehend the molecular structure and physiological function of the housefly larval peritrophic matrix （PM）, a mass spectrometry approach was used to investigate the PM protein composition. Methods The PM was dissected from the midgut of the third instar larvae, and protein extracted from the PM was evaluated using SDS-PAGE. A 1D-PAGE lane containing all protein bands was cut from top to bottom, the proteins in-gel trypsinised and analysed via shotgun liquid chromatography- tandem mass spectrometry （LC-MS/MS）. Results In total, 374 proteins, with molecular weights varying from 8.225, kD to 996.065 kD and isoelectric points ranging from 3.83 to 11.24 were successfully identified, most identified proteins were mainly related to immunity, digestion, nutrient metabolism and PM structure. Furthermore, many of these proteins were functionally associated with pattern binding, polysaccharide binding, structural constituent of peritrophic membrane and chitin binding, according to Gene Ontology annotation. Conclusion The PM protein composition, which provides a basis for further functional investigations of the identified proteins, will be useful for understanding the housefly larval gut immune system and may help to identify potential targets and exploit new bioinsecticides.
基金Supported by the National Natural Science Foundation of China (Grant No. 30671832)the Key Science and Technology Program of Guangzhou (Grant No. 2005Z32E0211)
文摘This work studied the transcriptional patterns of three antibacterial genes,attacin,defensin and cecropin,during the development of Musca domestica. Quantitative analysis by real-time PCR was performed on mRNA levels in different development stages and challenged 3rd-instar larva at different time points after challenge of Musca domestica. The results revealed a predominance of the transcripts of all three genes during the 3rd-instar larvae and the adults. In the meanwhile,it revealed the greatest increase in mRNA. The transcript levels increased to 801 times,1009 times and 2500 times respectively for cecropin,attacin and defensin in 3rd-instar larvae after challenging susceptible bacterium. The results suggested that the transcriptional patterns of Musca domestica antibacterial genes were different during the different growth stages as well as the microbial challenge encountered in 3rd-instar larvae.
基金Supported by Health Department of Guizhou Province Foundation(D-281)Yong Foundation of Zunyi Medical College(F-241)~~
文摘[Objective] The research aimed to observe the effects of Escherichia coli infection on the morphology of hemocytes of the 3rd stage larva of Musca domestica in vitro and understand the hemocytes types that take part in the cell immunity of Musca domestica larval.[Method] The hemcytes of the 3rd stage larva of Musca domestica were cultured in vitro and the hemocyte morphology was observed about 2,4,6,8 h after culture in vitro.After Escherichia coli were injected into the hemocytes of the 3rd stage larva of Musca domestica in vitro,the morphology changes of hemocytes were observed at different time after infection.[Result] The hemocytes of of the 3rd stage larva of Musca domestica was divided into five types about 2 h after hemoculture.The hemocytes partly adherence was seen about 6 h after hemoculture.The vacuolation and morpholysis was found in plasmatocytes after being infected by E.coli and a great quantity bacterium were gathered around granulocyte,but the morphology changes of hemocytes were not found in the prohemocyte,shprulocyte and oenocytoid.[Conclusion] The plasmatocyte and granulocyte were primary participants of the cell immunity of Musca domestica larval,but the prohemocyte,sphrulocyte and oenocytoid do not participate in the cell immune reactions.
文摘Amaranth is one of the most consumed vegetables in Niger Republic because of its nutritional values. However, the production of this plant requires nutrient-rich soils that are becoming scarce in most agricultural soils in Niger. This study aims to evaluate the fertilizing potential of the maggot production residue of Musca domestica L. 1758 and bovine excrement on the agronomic parameters of Amaranthus cruentus L., 1759. To do this, four densities (50, 100, 150, 200 g) of maggot production residue and bovine excrement were tested. Stem length, neck diameter and leaf number were strongly influenced by the interaction of the type of treatment (maggot production residue and bovine excrement) and dose. Dose 50 and dose 150 gave the best performance in length and diameter respectively for residue (length = 42.24 ± 8.98 cm;diameter = 0.88 ± 0.17 cm) and bovine droppings (length = 39.29 ± 8.10;diameter = 0.98 ± 0.77). On the leaf number side, no significant differences were observed between the doses for the residue. For bovine excrement, this number was higher at the 150 g dose (28.12 ± 4.98). The effect of the residue and bovine excrement on each corresponding dose shows that, for the stem length, only the 50 g dose was statistically influenced by the latter (P < 0.001). On the neck diameter side, only the 50 g and 100 g doses were statistically influenced by bovine residue and excrement (dose 50 g: P < 0.001;dose 100 g: P < 0.001). For each of these doses, the residue recorded the best performance both for the length of the rod and for the diameter at the collar. On the leaf number side, only the dose 50 g and 150 g varied statistically according to the type of fertilizer. At the 50 g dose, the residue recorded the largest number of leaves (27.10 ± 11.15), but the residue recorded the lowest number of leaves at the 100 g dose (21.01 ± 5.99). Foliar and root biomass varied statistically according to the dose within each fertilizer (foliar biomass: residue: P = 0.040;bovine excrement: P < 0.001;root biomass: re
文摘The ＂fly factor＂ was first discovered 〉60 years ago and describes the phe- nomenon that food currently or previously fed on by flies attracts more foraging flies than the same type and amount of food kept inaccessible to flies. Since then, there has been little progress made to understanding this phenomenon. Our objectives were （i） to demonstrate the existence of the fly factor in house flies, Musca domestica and （ii） to study underlying mechanisms that may cause or contribute to the fly factor. In 2-choice laboratory bioassays, we obtained unambiguous evidence for a fly factor phenomenon in house flies, in that we demonstrated that feeding flies are more attractive to foraging flies than are nonfeeding flies, and that fed-on food is more attractive to foraging flies than is ＂clean＂ food. Of the potential mechanisms （fly excreta, metabolic output parameters [elevated temperature, relative humidity, carbon dioxide]）, causing the fly factor, fly feces, and regurgitate do at- tract foraging flies but none of the metabolic output parameters of feeding flies does. Even though feeding flies produce significantly more CO2 than nonfeeding flies, elevated levels of CO2 have no behavior-modifying effect on flies. Preferential attraction of house flies to fly feces and regurgitate indicates that the flies sense airborne semiochemicals emana- ting from these sources. Hypothesizing that these semiochemicals are microbe-produced, future studies will aim at isolating and mass producing these microbes to accumulate semiochemicals for identification.
文摘The house fly, Musca domestica, has been implicated as a vector of Campy- lobacter spp., a major cause of human disease. Little is known whether house flies serve as biological amplifying hosts or mechanical vectors for Campylobacterjejuni. We in- vestigated the period after C. jejuni had been ingested by house flies in which viable C. jejuni colonies could be isolated from whole bodies, the vomitus and the excreta of adult M. domestica and evaluated the activation of innate immune responses of house flies to ingested C. jejuni over time. C. jejuni could be cultured from infected houseflies soon after ingestion but no countable C. jejuni colonies were observed 〉 24 h postingestion. We detected viable C. jejuni in house fly vomitus and excreta up to 4 h after ingestion, but no viable bacteria were detected 〉 8 h. Suppression subtractive hybridization identi- fied pathogen-induced gene expression in the intestinal tracts of adult house flies 4-24 h after ingesting C. jejuni. We measured the expression of immune regulatory （thor, JNK, and spheroide） and effector （cecropin, diptericin, attacin, defensing, and lysozyme） genes in C. jejuni-infected and -uninfected house flies using quantitative real time PCR. Some house fly factor, or combination of factors, eliminates C. jejuni within 24 h postingestion. Because C. jejuni is not amplified within the body of the housefly, this insect likely serves as a mechanical vector rather than as a true biological, amplifying vector for C. jejuni, and adds to our understanding of insect pathogen interactions.
