PROIMI   05436
PLANTA PILOTO DE PROCESOS INDUSTRIALES MICROBIOLOGICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
ANTIFUNGAL ACTIVITY AND SIDEROPHORE
Autor/es:
DELFINI CD,PAJOT H, VILLEGAS LB, BAIGORI MD.
Lugar:
SAN lUIS
Reunión:
Congreso; XLVII REUNION ANUAL SOCIEDAD ARGENTINA DE INVESTIGACION EN BIOQUIMICA Y BIOLOGIA MOLECULAR; 2011
Institución organizadora:
SAIB
Resumen:
ANTIFUNGAL ACTIVITY AND SIDEROPHORE
PRODUCTION OF CHITINOLYTIC BACTERIA AGAINST
Colletotrichum
Delfini CD, Pajot H, Villegas LB, Baigorí MD. PROIMI-CONICET. Av. Belgrano y Pje Caseros. Tucumán, Argentina. T4001MVB. E-mail: cdelfini47@hotmail.com
Four chitinolytic Bacillus strains were previously isolated from bat
guano (Taradita brasilensis). These bacteria showed antagonistic
properties, in vitro, against the phytopatogenic fungus
Colletotrichum acutatum and C. fragariae. Bacillus sp. PB1
showed the highest antifungal activity and was selected for further
studies. The aim of this work was to study the stability of the fungal
activity and its relationship with siderophore production. Selected
bacterium was incubated in SPI-colloidal chitin, SPI-pupa and
Standard nutrient (SN) liquid media, at 200 rpm 72h, at 28ºC.
Supernatants were assayed against C. cutatum and C. fragariae on
potato dextrose agar. Under all tested conditions, supernatants were
able to inhibit fungal growth. Major activity was reached on SN
medium. In order to evaluate the stability of the antifungal activity,
supernatants were treated with proteinase K or heat-treated at 50ºC
and 100ºC. Heat and proteinase K treated supernatants could were
only able to modify mycelial morphology. Bacillus sp. PB 1
produced siderophores as evidenced by positive reaction in FeCl 3
test. The presence of hydroxamate type siderophores was also
evidenced by standard the tetrazolium test. These results suggest
that Bacillus sp. PB 1 siderophores could play a significant role in
antifungal activity of selected chitinolytic bacteria