Table of Contents
What is the morphology of Aspergillus flavus?
Aspergillus flavus is a mycotoxigenic fungus that possesses the ability to produce B aflatoxins. It can be readily distinguished morphologically by the production of a bright yellow-green conidial color, when cultured on malt extract agar or Czapek yeast extract agar.
What is the shape of Aspergillus?
The genus Aspergillus is characterized by the formation of flask-shaped or cylindrical phialides either in a single or double series on the surface of a vesicle at the apex of a conidiophore (Raper and Fennell 1965).
Where is Aspergillus parasiticus found?
Aspergillus parasiticus can be found outdoors commonly within an agricultural setting of soil on fields and through the improper handling, drying, transportation and storage of grains and fresh produce. This fungus is also commonly found on the stems and roots of peanuts and other plants.
Which of the following media identifies species of Aspergillus?
Results: Aspergillus isolates were identified in the level of species using the differential culture media.
What does Aspergillus flavus look like under the microscope?
The microscopic characteristics of Aspergillus flavus isolate 5 under the basic biological light microscope showing the biseriate with philiades radiating from all sides (a); the globose conidia with varying sizes that are slightly roughened (b); and unbranched conidiophore which is nonseptate, rough, and hyaline (c).
What are the characteristics of Aspergillus flavus?
Aspergillus flavus colonies are commonly powdery masses of yellowish-green spores on the upper surface and reddish-gold on the lower surface. In both grains and legumes, infection is minimized to small areas, and discoloration and dullness of affected areas is often seen.
What are the colony morphology of Aspergillus?
Culture and conidial heads of Aspergillus fumigatus. Morphological description: On Czapek Dox agar, colonies are typically blue-green with a suede-like surface consisting of a dense felt of conidiophores. Conidial heads are typically columnar (up to 400 x 50 µm but often much shorter and smaller) and uniseriate.
What mycotoxins does Aspergillus produce?
The most potent Aspergillus-derived mycotoxins include aflatoxins, ochratoxins, gliotoxin, fumonisins, sterigmatocystin, and patulin.
What are mycotoxins PDF?
Mycotoxins are chemicals that are produced by filamentous fungi that affect human or animal. health. By convention, this excludes mushroom poisons. These fungi are called “toxigenic”
Which is the resistant structure in Aspergillus flavus?
Abstract. Invasive and allergic infections by Aspergillus flavus are more common in tropical and subtropical countries. The emergence of voriconazole (VRC) resistance in A. flavus impacts the management of aspergillosis, as azoles are used as the first-line and empirical therapy.
Does Aspergillus have branching hyphae?
Abstract. Filamentous fungi like Aspergillus nidulans can effectively colonize their surroundings by the formation of new branches along the existing hyphae.
What substance is produced by Aspergillus bacteria?
Aflatoxins are a family of toxins produced by certain fungi that are found on agricultural crops such as maize (corn), peanuts, cottonseed, and tree nuts. The main fungi that produce aflatoxins are Aspergillus flavus and Aspergillus parasiticus, which are abundant in warm and humid regions of the world.
What type of toxin is Aspergillus?
Aflatoxins are amongst the most poisonous mycotoxins and are produced by certain moulds (Aspergillus flavus and Aspergillus parasiticus) which grow in soil, decaying vegetation, hay, and grains.
What are the types of mycotoxin?
Types of Mycotoxins
- Aflatoxins: Aflatoxins can occur in all regions across the globe as a result of changing weather patterns, agricultural practices and more.
- Other Aspergillus mycotoxins:
- Trichothecenes:
- Zearalenone:
- Fumonisins:
- Ochratoxins/Citrinin:
- Other Penicillium mycotoxins:
- Patulin:
Is Aspergillus flavus filamentous?
Aspergillus flavus is a fungus. It grows by producing thread like branching filaments known as hyphae. Filamentous fungi such as A. flavus are sometimes called molds.
What are the characteristics of Aspergillus?
The following are some of the morphological characteristics of Aspergillus Fumigatus:
- They produce spores of between 200 and 400 mm.
- The color of the stipes is gray around the apex.
- They have a smooth surface.
- They have a small, columnous globuse.
- The surface of the conidia is either smooth or spinose.
Is Aspergillus Gram positive or negative?
Levels of gram-negative bacteria, Aspergillus fumigatus, dust, and endotoxin at compost plants.
What is the growth temperature of Aspergillus parasiticus?
A. parasiticus is further distinguished by its dark green colony colour. Aspergillus parasiticus colonies are dark green. The average growth temperature for this fungus ranges between 12 and 42 °C with the optimum temperature for growth is at 32 °C and no growth reported at 5 °C.
What is the difference between Aspergillus flavus and parasiticus?
Often confused with the closely related species, A. flavus, A. parasiticus has defined morphological and molecular differences. Aspergillus parasiticus is one of three fungi able to produce the mycotoxin, aflatoxin, one of the most carcinogenic naturally occurring substances.
What is the morphology of Aspergillus?
The genus Aspergillus is made up of more than 100 species. However, despite there being so many, they have certain aspects in common. One of its distinctive characteristics is its morphology, made up of conidiophores that end in an apical vesicle and that in turn present a basal foot cell that inserts into the hypha at the opposite end.
Does Aspergillus parasiticus produce norsoloronic acid?
Aspergillus parasiticus is a mold known to produce aflatoxins within the section Flavi. A mutant strain of Aspergillus parasiticus was reported as producing norsoloronic acid ( Lee et al., 1971 ). Norsoloronic acid was previously identified in another fungal strain, Aspergillus versicolor ( Hamasaki et al., 1967 ).