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Tag: Cladosporium

Cladosporium species in indoor environments

Cladosporium is a fungus that mostly found in indoor and outdoor molds. It is a species that formed in simple or branching chains and produced olive-green to brown colonies with pigmented conidia. Many of these Cladosporium species commonly found on living and dead plant materials. In which spores are dispersed by the wind that is why it is extremely abundant in outdoor air. On the other hand indoor species may grow when moisture of the surface is present. These species also belongs to a monophyletic group that is well bounded by having a unique coronate structures. In this current research a multilocus DNA sequence typing approach been conducted. As well as morphological examinations and cultural characteristics used as basis for identification and delimitation.


Diversity of Cladosporium in indoor environments

Cladosporium phylogeny and taxonomic structures have been reviewed extensively however, no enough study conducted about its presence in indoor environments. A molecular phylogenetic approach has been made to identify common indoor species. Since fungi usually present in indoor environment that produced toxins or holds allergens which cause hazards on health. That is why it is very important to know what are fungal species thrives indoors.


There were 46 species found indoors wherein four are found to be human-derived samples. Sixteen species identify as new in which 6 belong to Cladosporium complex and the most common are Cladosporium halotolerans. These indoor species grow better compared to other indoor fungi such as Aspergillus and Penicillium. As part of worldwide survey of the indoor mycobiota about 520 new Cladosporium isolates collected mainly from China, Europe, North America, South Africa and New Zealand.


Moreover, Cladosporium exhibits very condensed growth pattern forming round pigmented cells in the central colony and quick spore formation. It can also grow at lower available nutrients and the ability to deal with humidity changes in indoor situations. Interestingly the availability of water for these fungi is highly dynamic and influenced by changing temperature. The pure morphological identification of Cladosporium is clearly possible with the aid of molecular data and Cladosporium halotolerans is the most frequently isolated Cladosporium species indoors.


Source: Prepared by Joan Tura from  Studies in Mycology

Volume 89, March 2018, Pages 177-301



Fall and Winter Allergies

Well, the outdoor allergy season is almost over and we will soon be finished doing collections and providing information to the public through our reports that we produce.

The pollen in the air is generally at low levels or even absent on many days now. But people may still be suffering for a while in some areas where the temperatures will be remaining high enough for the fungal spores to continue growing and releasing the spores in the air. (more…)

What’s next for the allergy season?

This cold spring brought a late season for the trees but this does not have any impact on what is going to happen in August and the fall for outdoor pollen and mold spores. There are many weeds that cause seasonal allergies. Some of them include plantain, nettles, ragweed and others. But only weeds that are mostly or partially air pollinated are included in outdoor air samples. The weeds do not include ones that have a strong smell, colourful flowers or do not get airborne (Dandelion). These other weeds can cause allergic reactions but only on contact with the skin. (more…)

Where is spring and the pollen allergy season?

We hear it all the time. When will winter be over? Well not only are people saying it but so are the trees.

This winter the March weather has been very cold with lots of snow. April has begun with very cold temperatures as well and the temperatures are warming up very slowly. The sampler at our site in Ottawa on April 6th is still surrounded by snow. The winter snow cover is good for the trees since it provides protection for them during the cold winter months. What they don’t like is a stretch of warm weather in the spring followed by a cold snap for several days or even weeks. This can fool the trees into budding and it can have a profound effect on the pollen season to the point of almost eliminating it if the trees have started budding. We don’t have that problem this year so far. (more…)