Activity of Oyster Mushrooms, Genus Pleurotus (Agaricomycetes), on Lucilia cuprina (Diptera).

Lucilia cuprina is a vector of important diseases in humans and animals that causes myiasis in sheep, leading to enormous damage to the sheep sector. Chemical products are used to control these flies; however, there are reports of resistance in addition to these products causing toxicity to the environment, humans, and animals, so alternative controls have been studied to reduce these impacts. Pleurotus spp. are basidiomycete fungi and present bioactive compounds with medicinal properties. Due to the potential use of fungi to control Diptera, this study aimed to verify the activity of Pleurotus florida, P. ostreatus, and P. djamor in the control of larvae and adults of L. cuprina, as well as the effects of aqueous extracts of the fungi P. ostreatus, P. djamor, and P. florida on larvae and adults of L. cuprina. The aqueous extract from P. florida was the only one that showed larvicidal activity against L. cuprina, with a half-maximal effective concentration of 11.42 mg/mL. In the test with adult stages, 30 insects were used for each solution concentration, sprinkled with 1 mL of the solution. All aqueous extracts showed adulticidal activity at all concentrations, P. ostreatus showing the best results, with adult mortality ranging from 75.86 to 100%. Our results demonstrated an important larvicidal effect of P. florida and an adulticidal effect of all AE, with emphasis on P. ostreatus.

Microscopic alterations in Fasciola hepatica treated with the essential oils of Pelargonium graveolens and Citrus aurantium.

Fasciolosis is one of the most important parasitic diseases in animal health, affecting mainly ruminants, causing economic and productivity losses. This study aimed to evaluate the in vitro ovicidal and adulticidal activity of essential oils (EOs) from Pelargonium graveolens (geranium) and Citrus aurantium (sour orange) on Fasciola hepatica. Performed Gas Chromatography of EOs P. graveolens and C. aurantium, with major compound, citronellol (31.37 %) and limonene (93.89 %), respectively. For the cytotoxicity assay, the sour orange EO showed to be promising when used in lower concentrations. For the ovicidal tests, the eggs were incubated with geranium EOs at concentrations from 4.5 to 0.03375 mg/mL and sour orange at concentrations from 4.25 to 0.031875 mg/mL, along with controls. The viable eggs were counted on the 14th day post-incubation. Adult forms of F. hepatica were incubated containing the EOs and observed for 24 h after treatment, as well as the control groups. Later the specimens were fixed for histological analysis. Geranium and sour orange EOs in trematode eggs at the concentrations tested were 100 % effective in inactivating hatching (p < 0.05) when compared to the untreated control. In the adulticidal test, the essential oil of P. graveolens at both concentrations tested (0.0675 and 0.03375) within 15 h, promoted the death of flukes. For C. aurantium, 18 h was enough to inactivate all specimens, up to a concentration of 0.06375. The histological analysis, observed the accumulation of liquid in the tegument in the specimens incubated in C. aurantium and P. graveolens, with vacuolization in the tegument and spines, preventing externalization. The results of the study present OEs with efficient ovicidal and adulticidal activity.

Antioxidant and Nematocidal Effects of Several Oyster Mushroom Species of Genus Pleurotus (Agaricomycetes).

Cyathostomins are common intestinal nematodes that parasitize horses and can affect animal health and welfare. Alternative treatments are essential for sustainable parasite control, reducing the indiscriminate use of anthelmintics and their impacts on the environment, animals, and humans. Pleurotus spp. are edible medicinal mushrooms that possess several therapeutic properties, including antiparasitic and nematocidal activities. This study aimed to evaluate the antioxidant and nematocidal activity of aqueous extracts of three oyster species (P. florida, P. ostreatus, and P. djamor) on cyathostomine eggs in vitro. P. florida showed the highest activity against test organisms, inhibiting the hatching of eggs in up to 92.19% at the highest concentration (10%) of aqueous extract, with a mean lethal concentration (LC50) of 2.13%. In the aqueous extracts of P. ostreatus and P. djamor, nematocidal activity was reduced, inhibiting egg hatching by 55.46% (LC50, 7.44%) and 23.67%, respectively, at a concentration of 10%. P. florida showed higher antioxidant activity than that of the other species tested. Thus, P. florida may be considered a potential alternative for biological control in in vivo experiments with cyathostomins.

Nematocidal Effect of Oyster Culinary-Medicinal Mushroom Pleurotus ostreatus (Agaricomycetes) against Haemonchus contortus.

The nematocidal effect of Pleurotus ostreatus (white variety of oyster mushroom) aqueous extract (AE) was evaluated against Haemonchus contortus eggs and infective larvae (L3) in vitro and in artificially infected gerbils (Meriones unguiculatus). The chemical analyses indicated that constituents of AE are tridecanoic, tetradecanoic, linolelaidic, 9,15-octadecadienoic, and oxalic acids. P. ostreatus extract inhibited larval hatching by 100% at the concentration of 2.24 mg/mL and (50% effective concentration) EC50 of 0.73 mg/mL. In the larval development test, AE induced a larvicidal effect at the concentration of 50 mg/mL and EC50 of 17.24 mg/mL. The larval migration test revealed a reduction of 94.7% at a concentration of as low as 4 mg/mL and EC50 of 1.25 mg/mL. No significant effects of treatment with P. ostreatus AE were seen on H. contortus in the gerbil model. Thus, our results demonstrate an important nematocidal in vitro effect of P. ostreatus AE against the parasite H. contortus. However, further investigations are necessary to confirm the anthelmintic potential of P. ostreatus extract in small ruminants.