Brazil is a rich country in biodiversity, with numerous plants, animals and microorganisms
species, distributed in different biomes, presented as an important source of biological
products of interest to pharmaceutical, agricultural and food industries. The knowledge on
these organisms and on the compounds produced by them still little explored, so it is
important the development of biodiversity surveys, enabling the effective use of these
compounds. The aim of the present study was to carry out a biodiversity survey on genera of
filamentous fungi Aspergillus, Penicillium, Talaromyces, and Paecilomyces in Atlantic Forest
soil located in the Quadrilátero Ferrífero, and evaluate their enzyme production potential. The
isolates were morphologically characterized and evaluated according to macroscopic and
microscopic aspects. The toxin production evaluation (citrinin, aflatoxins and ochratoxin A)
was applied to aid in the identification of isolates by thin layer chromatography method, in
addition, the protein profile of some isolates were evaluated by MALDI-TOF MS. In vitro
enzyme production tests was performed screening the isolates for lipase, cellulase and
pectinase enzymes, so the enzymatic index of each fungus was calculated. From the
screening, one morphotype and one enzyme were selected and tested in submerged
fermentation. In total, 2035 fungal isolates were obtained, among which 37 of the genus
Aspergillus, 34 of Paecilomyces, 6 of Talaromyces and 1958 isolates of the genus
Penicillium. Through morphological characterization was possible to identify 34 isolates of
Aspergillus, 50 of Penicillium and 6 of Talaromyces, grouped into 3, 15 and 3 species,
respectively. All further isolates were grouped by their morphological similarities,
characterized and stored for later genetic analysis. The aflatoxin test was efficient to assist
with the identification of A. flavus and A. parasiticus, thus it was able to indicate 19 isolates
from the first specie and 2 from the second. The application of MALDI-TOF technique was
efficient in the aid to identify the filamentous fungi, resulting in good clusters and decreasing
the number of isolates to be subjected to further analysis. In the enzyme production tests, the
pectinase enzyme showed the higher number of isolates producers, and the morphotype
P51showed the highest enzymatic index, so it was selected for the submerged fermentation.
The isolated demonstrated to be a good exo-polygalacturonase producer and optimum time,
temperature and pH ranges were defined for its production. The results showed wide diversity
of species in the evaluated soil, with the possibility of new species that have not been
described before, besides the untapped biotechnological potential that can be better studied
and used in several production processes.
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