Interaction and ovicidal activity of nematophagous fungus Pochonia chlamydosporia on Taenia saginata eggs

Abstract

The ovicidal activity of the nematophagous fungi Pochonia chlamydosporia (isolates VC1 and VC4), Duddingtonia flagrans (isolate AC001) and Monacrosporium thaumasium (isolate NF34) on Taenia saginata eggs was evaluated under laboratory conditions. T. saginata eggs were plated on 2% water-agar with fungal isolates and controls without fungus and examined after 5, 10 and 15 days. At the end of the experiment P. chlamydosporia showed ovicidal activity against T. saginata eggs (p<0.05), mainly for internal egg colonization with results of 12.8% (VC1) and 2.2% (VC4); 18.1% (VC1) and 7.0% (VC4); 9.76% (VC1) and 8.0% (VC4) at 5, 10 and 15 days, respectively. The other fungi showed only lytic effect without morphological damage to the eggshell. Results demonstrated that P. chlamydosporia was effective in vitro against T. saginata eggs unlike the other fungi.

Biological control of Taenia saginata eggs

“…Note that type 1 and type 2 effects demonstrated by data do not classify PL1 as ovicide. This agrees with literature reporting that the aforementioned effects, though not proving ovicide, do contribute to biological control due to their viability-reducing capacities (Araújo et al, 2009). This fact has been earlier noted in other protocol-models involving genera Duddingtonia, and Monacrosporium and their effect on gastrointestinal infesting helminthic parasites .…”

“…Eggs of T. saginata are resistant to environment adverse condition, conventional sewerage treatment besides remaining viable up to 12 months due to the fact them having a hard shell protective later, embryophore (Urquhart et al, 1998). This provokes a need of using alternative ways of combating its environmental proliferation and subsequent human-animal infection, in this case biological means using ovicidal fungi with potential of propagating in fecal matter-conditions (Araújo et al, 2009). However the mechanism of ovicide fungal egg shell penetration is yet to be totally elucidated.…”

“…No fungi species distinct themselves due their ovicide nature more than P. lilacinus and P. chlamydosporia . Araújo et al (2009) reported that P. chlamydosporia (VC1 e VC4) samples destroyed eggs of T. saginata in vitro at the end of 15 days. When comparing to the efficiency of P. lilacinus in our work, it can be noted that: (1) in relation to type 1 effect, both did not post significant difference (p > 0.05).…”

Ação ovicida do extrato bruto enzimático do fungo Pochonia chlamydosporia sobre ovos de Ancylostoma sp

“…São divididos em predadores, endoparasitas e ovicidas. No grupo de fungos ovicidas, destacamse a espécie Pochonia chlamydosporia (VC4) que produz enzimas extracelulares do tipo proteases que desenvolvem um papel importante na infecção e na destruição (atividade ovicida) dos ovos de geo-helmintos 6 . De acordo com Esteves e cols 7 , alguns trabalhos têm demonstrado que isolados fúngicos de Pochonia chlamydosporia são capazes de produzir extratos enzimáticos contra vários tipos de substratos sólidos, e dentre esses, os polissacarídeos, as proteínas e os lipídios.…”

Avaliação da patogenicidade de isolados de Pochonia chlamydosporia e Purpureocillium lilacinum sobre ovos de Meloidogyne enterolobii

“…O parasitismo de ovos de nematoides por fungos vem sendo amplamente relatado nas últimas décadas (Chen et al, 1996;Araújo et al, 2009; , Llopes-Lorca et al, 2002, essa característica não ficou evidente no presente estudo para ambas as culturas.…”