101
Abstract
The study of the biodiversity of micromycetes is an embryonic science. The objective of our
work is to determine and characterise the micromycetes of the different substrates (sea water,
sediments, marine organisms and debris) of the port of Algiers and (sea water, mussels, oysters)
of the shellfish farm Cultmare Tipaza, by studying their morphological and cultural
characteristics, as well as their toxicity. We have identified 314 strains of filamentous fungal
fungi divided into 11 genera of which they are in descending order: Aspergillus66.56%,
Penicillium 26.84%, Eurotium 1.92%, Neurospora 1.28%, Mucor 0.96%, Emericella nidulans
0.64%, Alternaria, Cladosporium, Acremonium, Nigrospora and Scedosporuim 0.32% (for
each).
We used the acute toxicity test on Artemia salina larvae, which is a sensitive and reliable test,
low cost and easy to use. Due to its broad detection spectrum it is a good toxicity screening test
and in particular it is very suitable for the detection of metabolites. All the more so as A.salina is
also a marine organism and Artemia nauplii represent an indispensable trophic link to feed fry in
aquaculture.
For more in-depth study, we determined the median lethal concentration (CL 50 ) of the culture
extracts previously selected as potentially toxic. The results show that Penicillium, Aspergillus,
Fusarium and Mucorales are highly toxic strains for A.salina larvae, since in all the tests the
seven (7) fungal filtrates showed a positive effect on Artemia nauplius, whose LC 50 values
obtained were less than 30% in ascending order, 14.19%, 17.1%, 19.58% and 24.24% for
Penicillium, Mucor, Fusarium and Aspergillus, respectively.
For further investigation, we determined the median lethal concentration (LC 50 ) of the culture
extracts previously selected as potentially toxic. The results show that Penicillium, Aspergillus,
Fusarium and Mucorales are highly toxic strains for A.salina larvae, since in all the tests the
seven (7) fungal filtrates showed a positive effect on brine shrimp,with LC 50 values below 30%
in ascending order, 14.19%, 17.1%, 19.58% and 24.24% for Penicillium, Mucor, Fusarium and
Aspergillus, respectively.
The survival of the A.salina nauplii observed after 72 hours in this study could also be explained
by the presence of the non-toxic metabolites. In order to test this hypothesis, we tried to identify
these primary metabolites by extraction and purification by the thin layer chromatography
method. The results were satisfactory with the presence of numerous organic molecules such as,
phosphatidylcholine and phosphatidylethanolamine which can be beneficial to human health.
Key words: Micromycetes, port of Algies, Cultmare of Tipaza, OSMAC method, Artemia
salina, toxicity test, Metabolites extraction.
Abstract
The study of the biodiversity of micromycetes is an embryonic science. The objective of our
work is to determine and characterise the micromycetes of the different substrates (sea water,
sediments, marine organisms and debris) of the port of Algiers and (sea water, mussels, oysters)
of the shellfish farm Cultmare Tipaza, by studying their morphological and cultural
characteristics, as well as their toxicity. We have identified 314 strains of filamentous fungal
fungi divided into 11 genera of which they are in descending order: Aspergillus66.56%,
Penicillium 26.84%, Eurotium 1.92%, Neurospora 1.28%, Mucor 0.96%, Emericella nidulans
0.64%, Alternaria, Cladosporium, Acremonium, Nigrospora and Scedosporuim 0.32% (for
each).
We used the acute toxicity test on Artemia salina larvae, which is a sensitive and reliable test,
low cost and easy to use. Due to its broad detection spectrum it is a good toxicity screening test
and in particular it is very suitable for the detection of metabolites. All the more so as A.salina is
also a marine organism and Artemia nauplii represent an indispensable trophic link to feed fry in
aquaculture.
For more in-depth study, we determined the median lethal concentration (CL 50 ) of the culture
extracts previously selected as potentially toxic. The results show that Penicillium, Aspergillus,
Fusarium and Mucorales are highly toxic strains for A.salina larvae, since in all the tests the
seven (7) fungal filtrates showed a positive effect on Artemia nauplius, whose LC 50 values
obtained were less than 30% in ascending order, 14.19%, 17.1%, 19.58% and 24.24% for
Penicillium, Mucor, Fusarium and Aspergillus, respectively.
For further investigation, we determined the median lethal concentration (LC 50 ) of the culture
extracts previously selected as potentially toxic. The results show that Penicillium, Aspergillus,
Fusarium and Mucorales are highly toxic strains for A.salina larvae, since in all the tests the
seven (7) fungal filtrates showed a positive effect on brine shrimp,with LC 50 values below 30%
in ascending order, 14.19%, 17.1%, 19.58% and 24.24% for Penicillium, Mucor, Fusarium and
Aspergillus, respectively.
The survival of the A.salina nauplii observed after 72 hours in this study could also be explained
by the presence of the non-toxic metabolites. In order to test this hypothesis, we tried to identify
these primary metabolites by extraction and purification by the thin layer chromatography
method. The results were satisfactory with the presence of numerous organic molecules such as,
phosphatidylcholine and phosphatidylethanolamine which can be beneficial to human health.
Key words: Micromycetes, port of Algies, Cultmare of Tipaza, OSMAC method, Artemia
salina, toxicity test, Metabolites extraction.