The difference between Penicillium and Aspergillus

Penicillium generally refers to the genus Penicillium, which is related to the genus Aspergillus to some extent. If you are not very familiar with Penicillium, you must be familiar with penicillin, which is a very common antibiotic. This drug is extracted from Penicillium. Penicillium and Aspergillus are closely related, but they are also essentially different from each other, and the differences are what we need to understand. So, what is the difference between Penicillium and Aspergillus? Let’s take a look below.

Generally refers to the genus Penicillium. It is a genus of the widely distributed Ascomycetes, related to the genus Aspergillus. There are more than 200 species, the representative species is Penicillium glaucum, which is easy to separate from the soil or air. Branched, broom-like conidia extend from the mycelium into the air, and each apical stalk produces chain-shaped green-brown conidia. It is known that it is physiologically similar to Aspergillus, and many of them can produce mycotoxins.

Penicillium is commonly found on citrus and other fruits, refrigerated cheese and other foods contaminated by its spores. Its conidia are ubiquitous in the soil, in the air and on decaying substances. Penicillium lives a saprophytic life with a wide range of nutritional sources. It is an omnivorous fungus that can grow on any substrate containing organic matter.

The vegetative body of Penicillium is a colorless or light-colored mycelium, with diaphragms between the cells, and the cells are usually multinucleated. The entire mycelium is divided into matrix mycelium that extends into the nutrient matrix to absorb nutrients and aerial mycelium that extends into the air. Simple long and upright conidiophores are produced on the aerial mycelium, and the top branches in a special symmetrical or asymmetrical broom-like manner, called broom branches. The multipolar conidiophores finally produce many phialides, on which conidia chains are produced. Conidia are spherical to ovoid, green, blue or yellow, which are the unique colors of various Penicillium colonies that are commonly seen.

Aspergillus is an important fungus in the fermentation industry and food processing industry, and nearly 60 species have been used. More than 2,000 years ago, my country used it to make sauces, and it is also the main strain for making wine and vinegar. Modern industry uses Koji mold to produce various enzyme preparations (amylase, protease, pectinase, etc.) and organic acids (citric acid, gluconic acid, gallic acid, etc.), and it is used as a saccharifying feed strain in agriculture.

Yeast mold is widely distributed in grains, air, soil and various organic items. Some of the molds that grow on peanuts and rice can produce fungal toxins that are harmful to the human body, such as aflatoxin B1, which can cause cancer, while others can cause mold and rot in fruits, vegetables, and grains.

Most of the species in the genus Mycorrhizal have only been found in the asexual stage, and very few can form ascospores, so they are still classified as Deuteromycetes in mycology.