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1.
Appl Microbiol Biotechnol ; 107(12): 3859-3868, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37148335

RESUMO

The control of gastrointestinal parasites in animals has become more challenging every year due to parasite resistance to conventional chemical control, which has been observed worldwide. Ovicidal or opportunistic fungi do not form traps to capture larvae. Their mechanism of action is based on a mechanical/enzymatic process, which enables the penetration of their hyphae into helminth eggs, with subsequent internal colonization of these. The biological control with the Pochonia chlamydosporia fungus has been very promising in the treatment of environments and prevention. When used in intermediate hosts of Schistosoma mansoni, the fungus promoted a high percentage decrease in the population density of aquatic snails. Secondary metabolites were also found in P. chlamydosporia. Many of these compounds can be used by the chemical industry in the direction of a commercial product. This review aims to provide a description of P. chlamydosporia and its possible use as a biological parasitic controller. The ovicidal fungus P. chlamydosporia is effective in the control of parasites and goes far beyond the control of verminosis, intermediate hosts, and coccidia. It can also be used not only as biological controllers in natura but also as their metabolites and molecules can have chemical action against these organisms. KEY POINTS: • The use of the fungus P. chlamydosporia is promising in the control of helminths. • Metabolites and molecules of P. chlamydosporia may have chemical action in control.


Assuntos
Ascomicetos , Hypocreales , Doenças Parasitárias , Animais , Controle Biológico de Vetores
2.
Pathogens ; 10(5)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062798

RESUMO

Cooperia, Haemonchus and Oesophagostomum are the genera of gastrointestinal parasitic nematodes most prevalent in cattle and constitute a serious problem in cattle breeding due to the impact they have on meat and milk production and the high costs of control measures. The objective of the present work was to evaluate the efficiency of Bioverm® (Duddingtonia flagrans) in the control of gastrointestinal parasitism of young cattle raised in the field, in the Central-West region of Brazil. The experiment was conducted on a farm located in the municipality of Jangada, MT, where 18 cattle, Nelore and Aberdeen Angus breeds, aged six to ten months, were randomly divided into two groups (treated group and control group) and distributed in paddocks of Brachiaria decumbens, naturally infested by larvae of gastrointestinal nematodes. The animals in the treated group received 1g of Bioverm® for each 10 kg of body weight, administered daily with commercial feed, throughout a period of six months. In the control group, each animal received 1 g of rice bran for each 10 kg of body weight, without Bioverm®, added to the feed. Stool and pasture samples were collected every two weeks. The treated group showed a significant reduction (p < 0.05) in values of eggs per gram of feces (EPG) and a significant gain of body weight (p < 0.05) when compared to the control group. The fungal formulation Bioverm® was effective in pasture decontamination and consequently in reducing the occurrence of reinfection by nematodes. The animals treated with Bioverm® showed a lower parasitic load and greater weight gain.

3.
J Invertebr Pathol ; 158: 46-51, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30240583

RESUMO

Research in the area of sanitation in ruminant production has focused on discovery of potential agents for biological control of helminths with nematophagous fungi and has provided evidence of success. The antagonistic potential of the fungus Arthrobotrys cladodes var. macroides on infective larvae of bovine gastrointestinal parasitic nematodes was evaluated by scanning electron microscopy. Additionally, an in vivo test of the resistance to digestive processes and viability of the fungus was carried out using a formulation based on sodium alginate administered orally in cattle. Production of conidia and chlamydospores was high. In in vitro tests, the number of infective nematode larvae was reduced 68.7% by the fungus in the treated group compared to the control group. The interaction between the fungus and the nematodes was confirmed by scanning electron microscopy. Plates containing fecal samples collected after oral administration of 100 g of pellets containing the A. cladodes fungus showed that the fungus survived passage through the gastrointestinal tract of ruminants, grew on agar, formed traps and preyed on L3 larvae of gastrointestinal parasites. The results of the present study provide a new opportunity for alternative, environmentally safe control of ruminant nematodes.


Assuntos
Ascomicetos/fisiologia , Doenças dos Bovinos , Nematoides/parasitologia , Controle Biológico de Vetores/métodos , Animais , Bovinos , Doenças dos Bovinos/parasitologia
4.
Exp Parasitol ; 194: 9-15, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30237051

RESUMO

Biological control through the use of nematophagous fungi is a sustainable alternative for combatting helminthes in domestic animals and allows a reduction in the use of anthelmintics. The objective of this research was to evaluate the efficacy of the Arthrobotrys cladodes var macroides fungus in a pelleted formulation, based on sodium alginate and administered twice a week orally, as an alternative for the biological control of nematodes in field-grown young cattle. The experiment was conducted in a farm located in the municipality of Viçosa, MG, where 12 cattle, seven to nine months old, were allocated in two groups (treated group and control group) and distributed in pickets of Brachiaria decumbens, naturally infested with nematode larvae. The animals in the treated group received 1g of sodium alginate matrix pellets for every 10 kg of animal live weight, containing the nematophagous fungus Arthrobotrys cladodes var macroides and administered twice a week in conjunction with commercial feed. In the control group, each animal received 1 g of pellets for every 10 kg of animal live weight, without fungal mycelium added to the feed. Samples of feces and pastures were collected fortnightly for 12 months. The results showed that the most prevalent nematode genera in the coprocultures were Haemonchus sp., Cooperia sp. and Oesophagostomum sp., reflecting the results found in forage. The pasture that contained the animals that received feed with the fungus presented a reduction of 59% and 52% of larvae recovered at distances of 20 cm and 40 cm from the fecal pats, respectively. The mean number of eggs per gram of feces each month and animal body weight did not differ (p > 0.05) between the treated and control groups. Stool and soil samples from both groups were colonized by A. cladodes fungus and other fungi. Administration of Arthrobotrys cladodes var macroides mycelium by means of a sodium alginate matrix twice weekly reduced larval infestation of the surrounding pasture, indicating that this fungus may be a promising biological control of infecting forms of nematodes present in the environment.


Assuntos
Ascomicetos/fisiologia , Agentes de Controle Biológico , Doenças dos Bovinos/prevenção & controle , Fezes/parasitologia , Nematoides/microbiologia , Infecções por Nematoides/veterinária , Animais , Brasil , Bovinos , Doenças dos Bovinos/parasitologia , Infecções por Nematoides/prevenção & controle , Distribuição Aleatória , Estações do Ano , Microbiologia do Solo
5.
Exp Parasitol ; 184: 11-15, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29133187

RESUMO

Three experimental assays with Duddingtonia flagrans (isolated AC001) were carried out. The growth of the genus Duddingtonia present in formulation of rice bran, its predatory capability on Oesophagostomum spp. infective larvae (L3) in petri dishes (assay 1), its action in faecal cultures with eggs of that parasite (assay 2) and isolate's capability of predation after passing through gastrointestinal tract of swine (assay 3) was evaluated. At assay 3, feces were collected at time intervals of 12, 24, 36, 48, and 60 h after feed animals with the formulation. Assays 1 and 2 showed a statistical difference (p < 0.01) by the F test when comparing the treated group with the control group. At the both assays, was observed in the treated group a reduction percentage of 74.18% and 88.38%, respectively. In assay 3, there was a statistical difference between the treated group and the control group at all collection times (p < 0.01). Regarding the collection periods, there was no statistical difference over time in the treatment group (p > 0.05). The results demonstrate that the fungal isolate AC001 formulated in rice bran can prey on L3 of Oesophagostomum spp., in vitro and after passing through the gastrointestinal tract, without loss of viability. This isolate may be an alternative in the control of Oesophagostomum spp. in swine.


Assuntos
Duddingtonia/fisiologia , Enteropatias Parasitárias/veterinária , Esofagostomíase/veterinária , Controle Biológico de Vetores/métodos , Doenças dos Suínos/prevenção & controle , Animais , Duddingtonia/crescimento & desenvolvimento , Fezes/parasitologia , Feminino , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/prevenção & controle , Masculino , Esofagostomíase/prevenção & controle , Oesophagostomum/microbiologia , Oryza/microbiologia , Contagem de Ovos de Parasitas/veterinária , Esporos Fúngicos/crescimento & desenvolvimento , Suínos , Doenças dos Suínos/parasitologia
6.
J Invertebr Pathol ; 150: 1-5, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28859879

RESUMO

Gastrointestinal nematodes (GIN) can reduce or limit sheep production. Currently there is a clear deficiency in the action of drugs for the control of these parasites. Nematophagous fungi are natural enemies of GIN. Fungal combinations have potential for reducing GIN populations. The aim of this study was to evaluate the efficiency combinations of nematophagous fungi in sodium alginate matrix pellets for the biological control agents of gastrointestinal sheep nematode parasites in the field. The nematophagous fungi (0.2mg of fungus per kg of body weight), Arthrobotrys conoides, A. robusta, Duddingtonia flagrans, and Monacrosporium thaumasium were used. The treated groups were administered mycelium combinations in the following combinations: group 1 (D. flagrans+A. robusta); group 2 (M. thaumasium+A. conoides). The control group did not receive any fungal pellets. We used three groups with eight Santa Inês sheep each. Each animal was treated with approximately 1g of pellet per 10kg of live weight. During the experimental period, we evaluated: number of eggs per gram of feces (EPG), infective larvae (L3) per kg of dry matter, larvae recovered from coprocultures, packed cell volume, total plasma protein concentration of sheep, and environmental conditions. Group 2 EPG (M. thaumasium+A. conoides) differed from the control group in September and October. The number of L3/kg of dry matter recovered from animals of groups 1 and 2 at distances of 0-20 and 20-40cm from the fecal pats was lower than the control group. The packed cell volume and total plasma proteins of treated animals were similar to those of the control group. The combination of treatment groups (D. flagrans+A. robusta and M. thaumasium+A. conoides) reduced the number of L3/kg of pasture. Therefore, treatment of nematophagous fungal combinations have the potential to manage free-living stages of GIN in sheep.


Assuntos
Duddingtonia , Trato Gastrointestinal/microbiologia , Larva/microbiologia , Nematoides/microbiologia , Controle Biológico de Vetores/métodos , Animais , Agentes de Controle Biológico , Ovinos
7.
Electrophoresis ; 38(22-23): 2940-2946, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28777449

RESUMO

A bioreactor was built by means of immobilizing alpha-amylase from Aspergillus oryzae by encapsulation, through cryopolymerization of acrylamide monomers for the continuous starch hydrolysis. The starch hydrolysis was evaluated regarding pH, the concentration of immobilized amylase on cryogel, the concentration of starch solution and temperature. The maximum value for starch hydrolysis was achieved at pH 5.0, concentration of immobilized enzyme 111.44 mg amylase /gcryogel , concentration of starch solution 45 g/L and temperature of 35°C. The immobilized enzyme showed a conversion ratio ranging from 68.2 to 97.37%, depending on the pH and temperature employed. Thus, our results suggest that the alpha-amylase from A. oryzae immobilized on cryogel monoliths represents a potential process for industrial production of maltose from starch hydrolysis.


Assuntos
Reatores Biológicos , Criogéis/química , Enzimas Imobilizadas/metabolismo , Amido/metabolismo , alfa-Amilases/metabolismo , Aspergillus oryzae , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Maltose/metabolismo , Porosidade , Amido/análise , Amido/química , Temperatura , alfa-Amilases/química
8.
Biomed Res Int ; 2015: 474879, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26504809

RESUMO

The biocontrol is proven effective in reducing in vitro and in situ free-living stages of major gastrointestinal helminths, allowing progress in reducing losses by parasitism, maximizing production, and productivity. This study aimed at evaluating the predatory activity of fungal isolates of Duddingtonia flagrans and Clonostachys rosea species and its association on infective larvae (L3) of H. contortus in microplots formed by grasses and maintained in a protected environment. All groups were added with 10 mL of an aqueous suspension with 618 H. contortus L3 approximately. Group 1 was used as control and only received the infective larvae. Groups 2 and 3 received D. flagrans chlamydospores and C. rosea conidia at doses of 5 × 10(6). Group 4 received the combination of 5 × 10(6) D. flagrans chlamydospores + 5 × 10(6) C. rosea conidia. D. flagrans and C. rosea showed nematicidal effectiveness reducing by 91.5 and 88.9%, respectively, the population of H. contortus L3. However, when used in combination efficiency decreased to 74.5% predation of H. contortus L3. These results demonstrate the need for further studies to determine the existence of additive effects, synergistic or antagonistic, between these species.


Assuntos
Duddingtonia/fisiologia , Haemonchus/patogenicidade , Hypocreales/fisiologia , Controle Biológico de Vetores/métodos , Doenças dos Ovinos/prevenção & controle , Animais , Hemoncose/parasitologia , Hemoncose/prevenção & controle , Hemoncose/veterinária , Larva/patogenicidade , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
9.
Food Chem ; 174: 1-7, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25529644

RESUMO

A rapid method for the detection and quantification of the adulteration of milk powder by the addition of whey was assessed by measuring glycomacropeptide protein using mid-infrared spectroscopy (MIR). Fluid milk samples were dried and then spiked with different concentrations of GMP and whey. Calibration models were developed using multivariate techniques, from spectral data. For the principal component analysis and discriminant analysis, excellent percentages of correct classification were achieved in accordance with the increase in the proportion of whey samples. For partial least squares regression analysis, the correlation coefficient (r) and root mean square error of prediction (RMSEP) in the best model were 0.9885 and 1.17, respectively. The rapid analysis, low cost monitoring and high throughput number of samples tested per unit time indicate that MIR spectroscopy may hold potential as a rapid and reliable method for detecting milk powder frauds using cheese whey.


Assuntos
Contaminação de Alimentos/análise , Proteínas do Leite/análise , Leite/química , Espectrofotometria Infravermelho/métodos , Animais , Calibragem , Caseínas/análise , Análise dos Mínimos Quadrados , Fragmentos de Peptídeos/análise , Pós/análise , Análise de Componente Principal , Espectrofotometria Infravermelho/normas , Proteínas do Soro do Leite
10.
J Basic Microbiol ; 54 Suppl 1: S109-14, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25088293

RESUMO

Research involving the use of nematophagous fungi in the biological control of parasites of interest to veterinarians has occurred over recent years, with promising results. This article reports the infection of Parascaris equorum eggs by the fungus Pochonia chlamydosporia (isolates VC1 and VC4). Six groups were formed for each isolate, with six different culture media: 2% water-agar (2% WA); agar-chitin (AC); YPSSA (yeast extract, K2HPO4, MgSO4 ·7H2O, soluble starch); AELA extract (starch + water + agar); 2% corn-meal-agar (2% CMA); and 2% potato dextrose-agar (2% PDA). A total of 1000 eggs of P. equorum were transferred to each plate containing isolates grown for a period of 7 days (treatment group). Also, 1000 eggs were added to each plate without fungus (controlgroup). The plates were kept in an environmental chamber at 25 °C in the dark for 21 days. After, we analyzed the effects on ovicidal activity: effect 1 (accession shell); effect 2 (penetration hyphae); and effect 3 (destruction of the eggs). No differences were observed in the destruction of eggs between the two isolates. The decreasing effectiveness of the different culture media was: PDA (38.9%); CMA (38.3%); WA (36.7%); YPSSA (36.45%); and AC (32.5%). The highest percentage egg destruction was observed when the strains were grown in culture medium AELA (44.9%); this was the best medium.


Assuntos
Ascaridoidea/microbiologia , Interações Hospedeiro-Patógeno , Hypocreales/crescimento & desenvolvimento , Zigoto/microbiologia , Animais , Antibiose , Meios de Cultura/química , Escuridão , Hypocreales/fisiologia , Análise de Sobrevida , Temperatura , Tempo
11.
Acta Trop ; 139: 88-92, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25046695

RESUMO

Echinostoma paraensei is a trematode of the genus Echinostoma that causes echinostomiasis in humans. The objectives of this study were to: evaluate the ovicidal activity of the nematophagous fungus Pochonia chlamydosporia (VC1 and VC4) on a solid medium 2% water-agar (2% WA) against E. paraensei eggs (assay A); evaluate ovicidal effect (destruction of eggs) of the isolate VC4 in supplemented culture media (assay B); and evaluate the ovicidal ability of the crude extract (VC4) on E. paraensei eggs (assay C). Eggs of E. paraensei (assay A) were placed in Petri dishes containing 2% WA with an isolate of the fungus P. chlamydosporia (VC1 and VC4) grown for 10 days, and without fungus as a control and evaluated regarding their destruction. In assay B, eggs of E. paraensei were placed in Petri dishes with different supplemented culture media and with VC4 isolate and the destruction of eggs was examined at the end of 25 days of interaction. In assay C, effects of the crude extract of P. chlamydosporia (VC4) on eggs were evaluated at the end of 7 days. In assay A, there was no difference (p>0.05) in ovicidal activity among the tested isolates (VC1 and VC4); however, the highest percentage for ovicidal activity (type 3 effect) was demonstrated by the isolate VC4. In assay B, the culture medium starch-agar showed the best results for the destruction of the eggs, with a percentage of 46.6% at the end of the assay. In assay C, the crude extract of VC4 was effective in the destruction of E. paraensei eggs, with a percentage reduction of 53%. The results of this study demonstrate that a rich culture medium with a greater availability of carbon and nitrogen may interfere directly in the predatory characteristics of ovicidal fungi.


Assuntos
Anti-Helmínticos/química , Echinostoma/microbiologia , Hypocreales/química , Óvulo/microbiologia , Controle Biológico de Vetores/métodos , Animais , Hypocreales/fisiologia
12.
Acta Trop ; 127(3): 187-90, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23664843

RESUMO

The nematode Angiostrongylus cantonensis causes eosinophilic meningoencephalitis in humans and thus alternative methods of control should be studied. The objective of this work was to evaluate the predatory capacity of eight fungal isolates of the species Duddingtonia flagrans (AC001, CG768 and CG722), Monacrosporium thaumasium (NF34), M. sinense (SF53) and Arthrobotrys robusta (I31), A. cladodes (CG719) and A. conoides (I40) on first-stage larvae (L1) of A. cantonensis under laboratory conditions. The treated groups contained 1000 conidia of the fungal isolates and 1000 A. cantonensis L1 in Petri dishes containing 2% water-agar medium (2% WA). The control group (without fungi) contained only 1000 A. cantonensis L1 in 2% WA. Evidence of predation was observed at the end of 7 days. Percentage reductions in L1 were: AC001, 82.8%; CG768, 71.0%; CG722, 72.8%; NF34, 86.7%; SF53, 89.7%; I40, 48.3%; CG719, 84.7%; and I31, 80.4%. No significant difference was observed (p>0.01) between the actions of the isolates used; however, a difference was noted (p<0.01) in relation to the control group. The results of the present work, confirm previous reports of the effectiveness of the fungi D. flagrans, M. thaumasium, M. sinense and A. robusta in controlling larvae of potentially zoonotic nematodes, this being the first report on A. cantonensis L1.


Assuntos
Angiostrongylus cantonensis/microbiologia , Fungos/fisiologia , Animais , Interações Hospedeiro-Patógeno , Larva/microbiologia
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