Pleurotus pulmonarius

Description

Pleurotus pulmonarius is an edible mushroom that is very similar to Pleurotus ostreatus. The main differences are that P. pulmonarius has smaller and paler caps, develops more stems, and prefers warmer weather. This species is found in forests around the world, and is commonly cultivated in Europe and North America. It grows on dead and living wood of hardwoods, in shelf-like clusters, and has a white to grayish to lilac spore print. The mushroom is low in calories, fat, and sodium and is considered a healthy food option.

Studies suggest that P. pulmonarius and its extracts have potential medical benefits for various conditions. A substance called β-D-Glucan in P. pulmonarius can reduce pain sensitivity and has potential as a basis for new pain medications. Other studies found that extracts from P. pulmonarius have anti-inflammatory, antitumor, and antihyperglycemic effects, as well as potential for use in cancer treatment, diabetes treatment, and hay fever relief. P. pulmonarius extracts also have antimicrobial properties and exhibit antioxidant activity.

Common names: Indian Oyster, Italian Oyster, Phoenix Mushroom, Lung Oyster, German (Lungenseitling), Netherlands (Bleke oesterzwam).

Mushroom Identification

1. Cap

   The cap is 1.18 to 3.94 inches (3 to 10 cm) in diameter, and starts off convex before becoming flat or slightly depressed. Its fan-shaped, or semicircular outline, and nearly circular if growing on the tops of logs. When young and fresh, the cap can be somewhat greasy, but is usually bald and ranges in color from whitish to beige or pale tan. It lacks dark brown colorations and often results in a two-toned appearance as it fades when drying out. The margin is inrolled when young, later becoming wavy and sometimes very finely lined.

2. Gills

   The gills of this mushroom run down the stem, and can be either close or nearly distant, with short gills being frequent. They are initially whitish but can discolor yellowish with age.

3. Stem

   The stem can be absent or rudimentary but is often present. It measures 0.39 to 1.57 inches (1 to 4 cm) in length and 0.20 to 0.39 inches (0.5 to 1 cm) in thickness and can be eccentric or lateral, or even central. The stem is bald and whitish, with a white basal mycelium.

4. Flesh

   The flesh of this mushroom is thick and white and remains unchanged when sliced.

5. Odor and Taste

   Has a mushroom aroma with a mild taste.

6. Spore Print

   White, gray, lilac.

7. Habitat

   As a saprobic fungus, this species grows in shelf-like clusters on both dead and living wood of hardwoods, causing a white rot. It is widely distributed in North America and can be found from late spring through September.

8. Microscopic Features

   Spores 7–11 x 2–3 µm; cylindric-ellipsoid; smooth; hyaline in KOH; inamyloid. Hymenial cystidia not found. Pileipellis a cutis; elements 5–10 µm wide, smooth, hyaline in KOH.

Look-Alikes

1. Pleurotus populinus

   Restricted to grow on aspen and cottonwood.

2. Pleurocybella porrigens

   Grows on coniferous wood and develops translucent glassy white fruiting bodies without a stem, the crowded lamellae of which converge at the growth site.

Health Benefits

Anti-cancer

Researchers isolated polysaccharide-protein complexes from Pleurotus pulmonarius using hot-water extraction and tested their effects on liver cancer cells. They found that exposure to these compounds reduced cancer cell growth and invasion, as well as improved drug sensitivity to Cisplatin. In a mouse model, oral administration of these compounds inhibited cancer cell growth.

Leukaemia is a major cause of cancer-related death worldwide, and anemia is a symptom of this disease. Metabolites from extracts of Pleurotus pulmonarius were shown to increase the hemoglobin concentration and number of erythrocytes in a leukemia-induced rat model. These metabolites also prevented or restored leukocytosis, an increase in white blood cells that occurs in leukemia. The extracts also had immunomodulatory effects, increasing total leukocyte counts.

Extracts of Pleurotus pulmonarius were also applied to colon cancer cells in vitro. Both mycelium and fruiting body extracts contributed to anti-proliferative effects and down-regulated the ability of cancer cells to adhere to other cells, which is important for cancer progression and metastasis.

Anti-hypertensive

Hypertension, also referred to as high blood pressure, is a leading cause of death. Angiotensin converting enzyme (ACE) is a natural biological molecule that leads to constriction of the arteries. The pharmaceutical industry has developed drugs that inhibit ACE, and they are used as a treatment for hypertension. Pleurotus pulmonarius mycelium protein extracts have been explored in vitro for their use as an ACE inhibitor. Using Pleurotus pulmonarius mycelial water extracts, three proteins were identified as having ACE inhibitory effects. This provides the platform for further research and therapeutic developments using Phoenix Mushroom extracts and their biologically active components to treat hypertension.

Anti-oxidant

Everyday processes in the human body produce free radicals or reactive oxygen species (ROS) capable of oxidizing biological molecules such as including lipids, proteins and DNA. They play a critical role in disease development (e.g. arthritis, asthma, atherosclerosis, cancer, dementia, and Parkinson’s disease). Natural anti-oxidants are important to modify these effects and methanol extract of the fruiting bodies of Pleurotus pulmonarius have been shown to have antioxidant effects. There was a dose-dependent increase in the ability of Pleurotus pulmonarius to fight against free radicals and lipid peroxidation. The optimal concentration was observed at 2mg/ml. The most potent antioxidant activity of Pleurotus pulmonarius was against scavenging for ROS (hydrogen peroxide).

Anti-inflammatory

In vitro application of methanol-induced extraction of the fruiting bodies of Pleurotus pulmonarius to RAW cells showed a significant reduction in nitric oxide (NO) produced by the induction of an inflammatory response. RAW cells are used as they are the precursor to cells in our immune system that are responsible for an inflammatory response. The decrease in the presence of NO was produced in a dose-dependent manner (range 5mg/kg – 50mg/kg). NO is a molecule that can mediate pro-inflammatory responses and needs to be well controlled to avoid excessive inflammation that can cause disease or damage to tissue.

Anti-diabetic

It has been shown in vitro that protein extracts from Pleurotus pulmonarius have antidiabetic properties. The assays employed in this study monitored enzymes in the presence of protein extracts from Pleurotus pulmonarius. The enzymes are involved in carbohydrate metabolism and the study provides good evidence for the Pleurotus pulmonarius protein extracts as a method to inhibit these enzymes. A diabetic mouse model (alloxan treated) was used to examine the effect of aqueous Pleurotus pulmonarius extract and the results showed strong antihyperglycemic effects. These studies show that the use of Phoenix Mushroom could significantly reduce blood glucose elevations after food; therefore, it deserves consideration for its properties and potential use in the management of blood glucose levels, in particular in Diabetes Type II.

Anti-rhinitis

Allergic rhinitis is the most common atopic disease , atopy refers to the genetic predisposition to allergies. Allergic rhinitis is characterized by sneezing, itching and congestion of the nose and rhinorrhea. The administration of Pleurotus pulmonarius at a single dose of 500 mg/kg did not have a significant effect on mice with antigen-induced nasal rubbing and sneezing, but inhibition was observed following two weeks of treatment at 500 mg/kg; furthermore, after four weeks of administering the mice a dose of 200 mg/kg, a significant inhibition in symptoms were observed. Indicating that repeated doses of Pleurotus pulmonarius in this mouse model was suitable for treatment of the symptoms associated with Allergic rhinitis.

Anti-viral

The cause of acquired immunodeficiency syndrome (AIDS) is the human immunodeficiency virus (HIV). The HIV (HIV-1 RT) inhibition ratio of Pleurotus pulmonarius extract was tested at the concentration level of 1 mg/ml and showed HIV-1 RT inhibition of 70.8%. This provides good evidence in vitro for the potential anti-viral properties of Pleurotus pulmonarius.

Uses

A US company, Ecovative Design, has proposed the use of mycelium along with growth media as an alternative to petroleum-derived expanded polystyrene packaging or insulation. It can also be used to absorb and digest oil spills and other petroleum products.

Researchers in Mexico have shown that oyster mushrooms can degrade disposable diapers. In vivo studies have shown that consumption of oyster mushroom extract reduces cholesterol levels, an effect related to its beta-glucan content. However, this effect of mushrooms has not been proven in humans. Oyster mushrooms naturally contain up to 2.8% lovastatin (by dry weight).

Cooking Notes

Oyster mushrooms are often used as a delicacy in Japanese, Korean, and Chinese dishes: usually in plain, soup, stuffed, or stir-fried with soy sauce.

The taste of the mushrooms is described as mild, with a slight anise smell. Oyster mushrooms are best picked when they are young; as the mushrooms age, the flesh becomes firmer and the flavor becomes pungent and unpleasant.

Oyster mushrooms contain small amounts of arabitol, a sugar alcohol that can cause gastrointestinal distress in some people.

Cultivation Tips

Substrates for Fruiting:

Mushrooms are widely adaptable and can be produced from various organic wastes. The substrate materials proven to be the most productive are cereal straw (wheat, rice), hardwood sawdust, corn stover, bagasse, coffee waste, pulp mill sludge, cotton waste and many other agricultural and forestry waste by-products. Royse & Bahler found that adding 20% ​​alfalfa hay to wheat straw significantly improved yields. In their study, yields peaked when using a combination of wheat straw, alfalfa and slow-release nutrients.

Every compost producer knows that compost is considered "hot" because of its increased nitrogen content. While yields can be improved by adding these nitrogenous supplements, farmers must weigh whether this benefit will be offset by a possible increase in pollution rates. (Typically, the likelihood of a competitor getting moldy increases directly with nitrogen levels.)

Yield Potentials:

Biological efficiency 100-200%, largely affected by fruit body size at harvest and whether the fourth or fifth flush is reached.

Spawn Run:

1. Incubation Temperature: 75-85°F (24-29*C)

2. Relative Humidity: 90-100%

3. Duration: 8-14 days

4. CO2: >5000 ppm

5. Fresh Air Exchanges: 1 per hour

6. Light Requirements: n/a

Primordia Formation:

1. Initiation Temperature: 50-75° (80°) F (10-24° (27°) C)

2. Relative Humidity: 95-100%

3. Duration: 3-5 days

4. CO2: 400-800 ppm

5. Fresh Air Exchanges: 5-7 per hour

6. Light Requirements: 1000-1500 lux

Fruitbody Development:

1. Temperature: 60-80* F (18-27°C)

2. Relative Humidity: 85-90% (95%)

3. Duration: 3-5 days

4. CO2: 400-800 ppm

5. Fresh Air Exchanges: 5-7 per hour

6. Light Requirements: 1000-1500 lux

Cropping Cycle:

Every 7-10 days, for 3 flushes.

Although it is highly productive:

1. Continued growth after harvest.

2. Lack of cluster-bouquet formation.

3. Premature fruiting.

4. Quickness to spoil.

5. Production of high spore loads.

6. Attractiveness to fungus flies.

Synonyms and Varieties

• Agaricus petaloides Sommerfelt (1826), Supplementum florae lapponica, p. 258

• Agaricus pulmonarius Fries (1821), Systema mycologicum, 1, p. 187

• Agaricus pulmonarius subsp.* juglandis Fries (1874), Icones selectae hymenomycetum nondum delineatorum, 1(9), p. 98, tab. 87, fig. 2

• Dendrosarcus pulmonarius (Fries) Kuntze (1898), Revisio generum plantarum, 3, p. 464

• Pleurotus araucariicola Singer (1953), Lilloa, 26, p. 141

• Pleurotus ostreatus f. pulmonarius(Fries) Pilát (1934) [1933], Bulletin de la Société mycologique de France, 49(3-4), p. 281

• Pleurotus ostreatus var. pulmonarius (Fr.) Iordanov, 1979

Video

Photo sources:

Photo 1 - Author: wearethechampignons (CC BY-SA 4.0)

Photo 2 - Author: barbarab (CC BY-SA 4.0)

Photo 3 - Author: Tim Kennedy (CC BY-SA 4.0)

Photo 4 - Author: Amanita77 (CC BY-SA 3.0)