Penicillium

1. Penicillium

2. Characteristics • Penicillium belongs to the Ascomycetes group of fungi and also refers to as “Ascomycetous fungi”. It also produces characteristic bluish-green spores, due to which it also refers to as “Blue-green mould”. • Habitat and Distribution:It is commonly present in the soil, dead organic matter of plant and animal waste, air etc. These are having a heterotrophic or saprophytic mode of nutrition. Penicillium species are generally ubiquitous and widespread in distribution. • The growth of Penicillium species occurs at a mesophilic range of temperature (Between 20 – 30 Degrees Celsius), and a pH of 3 – 4.5. • Wonder Drug:Some strains of genus Penicillium produce various medically useful antibiotics. The first antibiotic was isolated from Penicillium notatum, by a scientist named Alexander Flemings in the year 1929, which he named as “Penicillin”. Penicillin functions as an antibacterial agent that mainly resists the growth of gram-positive bacteria.

3. Vegetative structure • Mycelium: It’s a vegetative part having a profuse branching, septate, cylindrical and thin-walled hyphae. The cell wall comprises of glucan. Hyphae appear small, septate, hyaline and 1.5-5 µm in diameter. A septum consists of a central pore. The growth of mycelium can occur superficially on the substratum or deep inside the substrate. A single cell of mycelium may contain one to many nuclei, i.e. Uni-nucleate or multi-nucleate.

4. Contd. • Conidiophore: Penicillium species are generally consisting of a long, filamentous-like conidiophore. Depending on various species, the conidiophore may be either symmetrical or asymmetrical in structure and can be simple or branched. Metullae is a secondary branch originates from the long conidiophore, and also refers as primary sterigmata. Phialides is the secondary sterigmata that resemble the flask-like structure pinches out of the secondary branch (metullae) of the conidiophore. The arrangement of phialides is very typical which resemble the brush-like clusters known as “Penicilli”. • Conidia: The members of genus Penicillium generally comprise of conidial chains on the flask-like phialides. These are having a diameter of 2.5-5 µm. The conidial spores or conidiospores exist as round and unicellular cells. It has an arrangement in bicipital succession.

5. Interesting facts about penicillium • Origination:Penicillium is a term derived from a Latin word “Penicillus” which means paintbrush as its structure is very much similar like a paintbrush. Penicillin was the first antibiotic introduced by a scientist named Alexander Fleming, which he isolated from the species (Penicillium notatum). • Ecological Impact:The growth of Penicillium species is the common cause of fruits and vegetable decay and one of the primary reason of post-harvest losses. It can also affect the economy, as it may even grow on fabrics, leather, wood etc.

6. Human Health:It can grow on a variety of foodstuffs (commonly fruits and vegetables) and results to cause of food spoilage. Some of the Penicillium strains produce mycotoxins that may cause various allergic reactions.Example: P. verrucosum releases ochratoxin-A mycotoxin that shows nephrotoxic (kidney damage) and carcinogenic effects (cancer). • Scope:Some of the strains are harmful to the humankind and the economy of our country. Still, few are also crucial in the field of industrial field, medicine, food microbiology, bio-deterioration etc. Penicillium strains play an essential role in the commercial production of cheese, organic acids and antibiotics. • Identification:One of the easiest ways to identify Penicillium species is through the branching pattern of the conidiophore. The conidiophores give rise to the secondary branches (Metullae) that further give rise to the tertiary branches (Phialides or Sterigmata), which makes it distinct from the other groups of fungi.

7. Reproduction 1-Vegetative reproduction 2-Asexual reproduction 3-Sexual reproduction

9. Economical Importance of Penicillium • Penicillium species are very important economically. They produce many food products, organic acids, antibiotics and mycotoxins. • Cheese production- many Penicillium species are used in the production of different kinds of cheese, e.g. blue cheese, P. camemberti forms Camembert and Brie cheese and P. roqueforti forms Roquefort cheese • Enzymes and Organic acids production- many Penicillium species are used in the production of organic acids such as citric acid, gluconic acid, tartaric acid and enzymes like amylases, proteases, cellulase, lipase and pectinase • Antibiotic (Penicillin) production- In 1929 Alexander Fleming isolated the antibiotic Penicillin from penicillium, which inhibited the growth of Gram-positive bacteria. Later Florey and Chain extracted and produced Penicillin from the moulds to treat soldiers of the world war II • Penicillin is produced by Penicillium chrysogenum (earlier known as Penicillium notatum). The naturally occurring penicillins are Penicillin G (Benzylpenicillin), which is given by intramuscular injection and Penicillin V (Phenoxymethylpenicillin) given orally to treat various infections. Penicillin act by inhibiting enzymes responsible for the cell wall formation of bacteria and activating enzymes responsible for the breakdown of the protective wall of the bacteria. • Penicillium species are also used in the production of antifungal drug and tumour suppressing compounds • Penicillium species are also used in mycoremediation, i.e. bioremediation process using fungus to clean the environment due to their ability to breakdown xenobiotic compounds