Mold Testing and Bacteria Testing

Trusted Laboratories

Trusted Laboratories

Phone: (905)290-9101
Toll Free: 1-866-813-0648

Worried About Mold?

Click ** Get Your Free Assessment Now!**

  • Home
  • About Us
  • Services
    • Mold Testing
    • Bacteria Testing
    • Legionella Testing
    • Cannabis Testing
    • Antimicrobial effectiveness testing
    • Biological Indicators and Sterilization Process
    • Contract Microbiological Research
    • Environmental Monitoring & Bioburden Testing
    • Material Fungus Resistance Testing
    • Materials Standard Testing
    • Cannabis Licence
  • Accreditation
  • Mold Test Kits
  • View Courses
  • Freebies
    • Live Presentations
    • FREE Mold Inspection Quiz
    • FREE Mold Spore Identification Quiz
  • Resources
    • Chain of Custody Form
    • Ask a Question
    • How to Take Samples
    • Results Interpretation
    • Mold and Bacteria Pictures
    • Jobs
  • Contact us
You are here: Home / Mold / Penicillium

Penicillium

Dr Jackson Kung'u

Penicillium species: the mould that saved millions of lives

Penicillium chrysogenum as seen under a microscope
Penicillium chrysogenum spores

Penicillium is a group (Genus) of moulds found everywhere world-wide. It is the mould that saved millions of lives by producing the first ever known modern antibiotic, the penicillin. The discovery of penicillin from the fungus Penicillium chrysogenum (then known as Penicillium notatum) by Sir Alexander Fleming in 1928, perfected the treatment of bacterial infections.

The name Penicillium comes from the resemblance of the spore producing structures (conidiophores) of the fungus to a paintbrush (penicillus is the Latin word for paintbrush). They are found in soil, decaying vegetation, air and are common contaminants on various substances.

Penicillium causes food spoilage, colonizes leather objects and is an indicator organism for dampness indoors. Some species are known to produce toxic compounds (mycotoxins). The spores can trigger allergic reactions in individuals sensitive to mould. Therefore, the health of occupants may be adversely affected in an environment that has an amplification of  Penicillium.

About 200 species of Penicillium have been described. They are commonly called the blue or green moulds because they produce enormous quantities of greenish, bluish or yellowish spores which give them their characteristic colours. Spores from this species of mold are found everywhere in the air and soil. As mentioned earlier, Penicillium species are one of the most common causes of spoilage of fruits and vegetables. For example, P.  italicum and P.  digitatum are common causes of rot of citrus fruits, while P. expansum is known to spoil apples.

Penicillium chrysogenum is the most common species in indoor environment. It is widespread and has a wide range of habitats. In indoor environment, it is extremely common on damp building materials, walls and wallpaper, floor, carpet mattress and upholstered furniture dust. It produces a number of toxins of moderate toxicity. It is allergenic (i.e., it can trigger allergic reactions).

Some species of Penicillium can also infect immunocompromised individuals. For example, P. marneffei is pathogenic particularly in patients with AIDS and its isolation from blood is considered as an HIV marker in endemic areas. It has emerged as the third most common opportunistic pathogen among HIV-positive individuals in Southeast Asia where it is endemic and infects bamboo rats which serve as reservoirs for human infections.

Penicillium as A Producer of Mycotoxins

Penicillium species other than  P. marneffei are commonly considered as contaminants but they are also known to produce mycotoxins. For example, P. verrucosum  produces a mycotoxin, ochratoxin A ,  which is damaging to the kidney (nephrotoxic) and could be cancer causing (carcinogenic). The production of the toxin usually occurs in cereal grains at cold climates but has been isolated in buildings contaminated with Penicillium. Other mycotoxins include patulin, citrinin, and citroviridin among others.

Identification of Penicillium Species

Many species of Penicillium are important in biotechnology, food, medicine, biodeterioration and other applied fields. So, correct identification of these species is of vital importance. Microscopically, Penicillium species are identified primarily based on the branching habit of the conidiophores the species exhibits. Conidiophores can be simple or branched.

Details of Penicillium identification are beyond the scope of this article. However many commercial labs are incapable of correctly identifying Penicillium to species level. If you have questions or need mold testing and identification services, please contact us by phone or email.

author avatar
Dr Jackson Kung'u
Dr. Jackson Kung’u is a Microbiologist who has specialized in the field of mycology (the study of moulds and yeasts). He is a member of the Mycological Society of America. He graduated from the University of Kent at Canterbury, UK, with a Masters degree in Fungal Technology and a PhD in Microbiology. He has published several research papers in international scientific journals. Jackson has analyzed thousands of mould samples from across Canada. He also regularly teaches a course on how to recognize mould, perform effective sampling and interpret laboratory results. Jackson provides how-to advice on mould and bacteria issues. Get more information about indoor mould and bacteria at www.drjacksonkungu.com.
See Full Bio
social network icon social network icon

No related posts.

Filed Under: Mold Tagged With: Paecilomyces, Penicillium, Penicillium chrysogenum, Penicillium digitatum, Penicillium expansum, Penicillium italicum

How Much Do You Know About Mold?

Take a 3 minutes Quiz and find out how much you know about mold. To start the Quiz please Click START QUIZ below.

General Knowledge Mold Quiz

General knowledge mold quiz- Try it, it's fun!
Complete the form below to see results
Share your result via
Facebook X Pinterest LinkedIn Email

By the way, we have online mold courses at https://www.mytrainingcourses.ca

« Paecilomyces
Phialophora »

Online Training

Online Mold Recognition, Assessment
And Control Course. Register Today!

Mold Testing Kits

Suffer from asthma or allergies?
Order air mold test kit Today- $116!

Bacteria Testing

‪MBL specializes in identification and enumeration of mold and bacteria!

Legionella Testing

Legionella Testing by CALA-accredited laboratory. Call Today!

Laboratory Mold Testing

MBL Specializes in Mold Identification and Mold Testing!

Mold Inspection Services

Mold And Mildew Testing By Mold
Inspection Specialists. Call Now!

Recent Posts

Is E. coli Airborne? Separating Facts from Myths in Bacterial Sampling

In the world of indoor environmental quality, bacterial contamination often raises questions, especially when dealing with sewage damage. A recent … [Read More...]

 - Mold Testing and Bacteria Testing

Is “Black Mold” Equivalent to “Toxic Mold”?

Is "Black Mold" Equivalent to "Toxic Mold"? No, black mold is not equivalent to toxic mold. "Black Mold" is a term that is often used incorrectly to … [Read More...]

 - Mold Testing and Bacteria Testing

Exploring Non-Tuberculous Mycobacteria (NTM): Understanding Characteristics and Implications

What Are Non-tuberculous Mycobacteria (NTM)? Non-tuberculous Mycobacteria are mycobacteria other than Mycobacterium tuberculosis and M. leprae, and … [Read More...]

Learn With Us…

Courses

  • Mold Inspection, Identification and Control
  • Fungal Spore Identification
  • Mold Inspection Business Course
  • How to take Mold Samples Course
  • Coliform Testing
  • WHMIS
  • INTERESTING KNOWLEDGE QUIZES

Get In Touch

By phone or by email
905-290-9101
Email

Our Location
1020 Brevik Place, Unit 1A • Mississauga, ON L4W 4N7
(Phone: 905-290-9101 • toll-free: 1-866-813-0648 • fax: 905-290-0499.)

  • Email
  • Facebook
  • LinkedIn
  • Twitter
  • YouTube

Search this Site

Recent Posts

  • Is E. coli Airborne? Separating Facts from Myths in Bacterial Sampling
  • Is “Black Mold” Equivalent to “Toxic Mold”?
  • Exploring Non-Tuberculous Mycobacteria (NTM): Understanding Characteristics and Implications

Useful Links

  • Chain of Custody Download
  • Contact us
  • Privacy policy

Copyright © 2025 · Mold & Bacteria Consulting Laboratories. Log in