Antifungal and marker effects of Talisia esculenta lectin on Microsporum canis in vitro.
OBJECTIVE
The purpose of this study was to demonstrate the usefulness of lectin obtained from Talisia esculenta (TEL) seeds as a tool to recognize and study Microsporum canis. For this purpose, we investigated the antifungal and marker action of this lectin and the relationship of these effects with the presence of carbohydrates on the structure of this fungus.


RESULTS
The in vitro antifungal activity of TEL was analysed by broth microdilution assay. In addition, TEL was assessed against the arthroconidia present on hairs obtained from infected dogs and cats. The affinity of fluorescein isothiocyanate (FITC)-labelled TEL for macroconidia and arthroconidia of M. canis was also tested. The effects of TEL on the growth of the M. canis strains began with 0.125 mg ml(-1), and 100% inhibition was obtained with a concentration of 2 mg ml(-1). The addition of carbohydrates, especially N-acetyl-glucosamine and d-mannose, inhibited these antifungal effects. TEL was able to inhibit the growth of arthroconidial chitin-rich forms of M. canis obtained from hairs of infected animals and strains cultured in Sabouraud agar. FITC-labelled TEL efficiently marked macroconidial and arthroconidial forms of M. canis, as shown by fluorescent microscopy.


CONCLUSIONS
These results show that the inhibitory effects of TEL on M. canis growth may be related to the interaction of lectin with the carbohydrates present at the micro-organism's surface, mainly D-mannose and N-acetyl-glucosamine.


CONCLUSIONS
Talisia esculenta can be used as an important tool in the biochemical study of M. canis or as a molecule to recognize this dermatophyte in infected tissue.
Pinheiro
A Q
AQ
Veterinary Faculty, State University of Ceará, Fortaleza-CE, Brazil. adrianaqfavet@yahoo.com.br
Melo
D F
DF
Macedo
L M
LM
Freire
M G M
MG
Rocha
M F G
MF
Sidrim
J J C
JJ
Brilhante
R S N
RS
Teixeira
E H
EH
Campello
C C
CC
Pinheiro
D C S N
DC
Lima
M G S
MG
D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D001681:Biological Assay; D002371:Cat Diseases / Q000382:microbiology*; D002415:Cats; D003881:Dermatomycoses / Q000382:microbiology / Q000662:veterinary*; D004283:Dog Diseases / Q000382:microbiology*; D004285:Dogs; D006197:Hair / Q000382:microbiology; D008826:Microbial Sensitivity Tests; D008864:Microsporum / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification*; D037121:Plant Lectins / Q000494:pharmacology*; D029631:Sapindaceae / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry; D013172:Spores, Fungal / Q000187:drug effects
D000935:Antifungal Agents; D037121:Plant Lectins