**2.8** *Fomitopsis officinalis*

This is a bracket fungus, commonly known as white agaric, agaric, puring agaric, and larch agaric [21, 46]. Apart from its medicinal properties, it is also known to be used as tinder and with the common names as tinder and touchwood [17]. This species is considered as the oldest traditional medicinal mushroom in Asia that has been used by both the Greeks and Romans. It was used in ancient times as an antidote for poisoning [36]. In the past century, it was recorded for use as a laxative, in preventing flatulence and to treat the intestine of worms and parasites [53]. It has contributed to Africa and the tropics for the successful treatment of malaria. Just prior to the midtwentieth century, it was still used as a tonic for bronchial asthma and night sweats in tuberculosis patients [48, 55]. *Fomitopsis officinalis* is illustrated in **Figure 9**.

*Fomitopsis officinalis* species are among the most studied species for their medicinal properties. Although bioactivity studies for disease treatment have been done in most

*Medicinal Mushroom of Potential Pharmaceutical Toxic Importance: Contribution… DOI: http://dx.doi.org/10.5772/intechopen.103845*

**Figure 9.** Fomitopsis officinalis *(White agaric) [30].*

cases this species is not highly recognized to be of pharmaceutical importance for the treatment of the diseases studied and therefore not approved by the FDA [21]. In addition, for its use as dietary supplement/nutraceuticals more research is needed before a strong consideration for use as a supplement, as some species have been reported to show toxicity if consumed more than the recommended established doses [34].

#### **2.9** *Pleurotus ostreatus*

*Pleurotus ostreatus*, commonly called the oyster mushroom, oyster fungus, or hiratake, is a widely consumed edible mushroom [63]. It was first cultivated in Germany in subsistence farming to support food sources for the population during the World wars [63], and is currently widely cultivated on a commercial large-scale production worldwide for sustainable food production. It is closely related to the widely cultivated king oyster mushroom. This species of mushrooms is industrially used for mycoremediation purposes [9, 64]. The oyster mushroom is considered as one of the most widely sought-after wild mushrooms, even though they are highly cultivated on straw and other substrate media. It produces the bittersweet aroma of benzaldehyde, which is a characteristic of bitter almonds [15, 65]. The species of Pleurotus are shown in **Figure 10**.

The gastronomic effects are described by the addition of either the dried fruiting bodies of the oyster fungus *P. ostreatus*, or the ethanolic extract, to the diet of normal Wistar male rats and a strain with hereditary hyper-cholesterolemia. The addition of the dry oyster fungus to the diet is linked to a two-fold significant increase of the triacylglycerol (TAG) level in the plasma of both treatment groups of rats when

**Figure 10.** *(a)* Pleurotus ostreatus *growing on a tree trunk. (b)* Pleurotus ostreatus *cultivated in Cameroon.*

compared with their respective controls [66–68]. On the contrary, the ethanolic extract alone did not significantly increase TAG levels. There was no significant change for total cholesterol and its high- and low-density lipoprotein fractions in the plasma, as well as the calculated atherogenic index.
