Italian Journal of Mycology

Trichothecenes B and ergosterol content evaluation in mature grains of durum wheat genotypes contaminated by Fusarium culmorum

Salah Hadjout, Mohamed Zouidi — Wed, 08 Feb 2023 00:00:00 +0100

The interest of this present work is to compare two selected durum wheat lines (G1 and G4) with their sensitive parents to fusarium head blight by determining the mycotoxin and ergosterol content in their mature grains. These lines are homozygous, fixed, obtained by the classical genealogical selection, and composed of seeds from diallel crosses between 4 parental varieties Saadi, Simeto, Ardente, and Waha. For this purpose, the grains of the studied genotypes (lines and parental varieties) were tested in the laboratory for their content of Trichothecenes B mycotoxins (TCTB) and ergosterol at full grain maturity using high-performance liquid chromatographic – diode array detection (HPLC-DAD). Fungal biomass was estimated by the content of ergosterol. However, the level of toxins was assessed by the levels of TCTB produced by the different studied isolates. The results obtained showed that the lines derived from crosses and, especially the G1 line, accumulated levels of TCTB and ergosterol significantly lower than their parents. Our findings open up a new avenue of investigation into fusarium head blight in Algeria, including the search for mycotoxins as potential causes of poorly understood human diseases and the factors that contribute to their accumulation in grains.

Screening and virulence of Iranian isolates of Beauveria bassiana for potential management of Sunn Pest (Eurygaster integriceps Puton) in relation to cold activity

Farzaneh Parsi, Samira Peighami Ashnaei, Shahram Shahroukhi Khaneghah — Wed, 08 Feb 2023 00:00:00 +0100

Environmental abiotic factors, such as low temperatures, restrict the application of entomopathogenic fungi well-known biological control agents against agricultural pests. Among 60 Iranian isolates collected in Central Iran that were exposed to cold stress, four isolates were identified as potential candidates for further investigation. One hundred percent of the conidia of these four isolates germinated and subsequently produced conidia. Their virulence against Sunn Pest (Eurygaster integriceps Puton) varied between isolates. After applying cold stress (4 °C), Vesh 1-8 isolate with sporulation of 6.5 × 10 7 conidia mL^-1, 50% mortality and LT in 3/4 days was the most cold-tolerant isolate. Cold-active germination and growth of the biocontrol fungal isolates are important to industrialize the products with a high potential against target pests in different environmental conditions.

The king oyster mushroom Pleurotus eryngii behaves as a necrotrophic pathogen of Eryngium campestre

Juan Ramon Carlavilla, José Luis Manjón — Wed, 08 Feb 2023 00:00:00 +0100

Under natural conditions in Spain, the fruiting bodies of Pleurotus eryngii var. eryngii, a basidomycete of great economic and gastronomic importance, appears at the base of the stem of (mainly) Eryngium campestre, surrounded by the plant’s dried-out basal leaves. Traditionally collected in the wild of Mediterranean areas, this fungus is now cultivated all over the world for its culinary and even medicinal properties. However, controversy exists regarding its lifestyle. Some authors indicate it is a saprotroph, while others suggest it is a weak or even virulent parasite that causes male sterility in E. campestre. The present work aims to clarify whether P. eryngii behaves as a saprotroph, a weak or virulent parasite to E. campestre. The soil beside the roots of naturally growing E. campestre plants was inoculated with a commercial strain of P. eryngii, and the trophic mode of the fungus recorded. Soil and root samples were subjected to molecular analysis to confirm the absence/presence of the fungus. The death of the plants and the molecular analysis showed P. eryngii is a facultative necrotrophic parasite of E. campestre in natural conditions and a virulent parasite in greenhouse.

Chemical composition and nutritional value of nine wild edible mushrooms from Northwestern Tunisia

Mon, 13 Feb 2023 00:00:00 +0100

The chemical composition evaluation and the nutritional value of nine most widespread wild edible mushroom species (Agaricus arvensis, Cantharellus cibarius, C. lutescens, Craterellus cornucopioides, Hericium erinaceus, Hydnum repandum, Lactarius deliciosus, Pleurotus pulmonarius, and Ramaria flavescens) and much collected in northwestern Tunisia, have been analyzed and determined according to standard methodologies. The chemical composition of edible mushrooms was validated by statistical PCA analyzes. Overall results showed that most of the studied species had interesting values for almost all measured variables. In particular, the species H. erinaceus had the highest quantity of carbohydrates (89.70%), oleic (24.05%), and docosahexaenoic acid (3.19%), phenolic compounds (11.25 mg g^-1 dw), flavonoids (57.5 mg g^-1 dw), and minerals K, Mg and Ca but also the lowest content of proteins (4.80%) and carbohydrates (3.96%). On the other hand, the species P. pulmonarius had the lowest lipid content (7.30%) and the lowest caloric value (371.76 Kcal). These promising data can be exploited by taking advantage of the high-quality nutritional value of these interesting species.

Morphological observation and biomass formation in different edible medicinal Morchella collections (Pezizomycetes, Ascomycota)

Tue, 14 Mar 2023 00:00:00 +0100

The ascomycetes in the genus Morchella (commonly called morels) have a considerable economic and biotechnological value for their culinary and medicinal proprieties. However, their biotechnological interest is not limited to the fruiting body cultivation, but also in mycelial production to obtain bioactive compounds and other biotech products. In order to better exploit the biotechnological potentialities of morels it is necessary to improve the knowledge on their biology and mycelial characteristics. In this paper morphological and growth characteristics of mycelia, as well as biomass formation of Italian collections of five edible medicinal Morchella species [M. esculenta (L.) Pers., M. dunalii Boud., M. importuna M. Kuo, O'Donnell & T.J. Volk, M. disparilis Loizides & P.-A. Moreau and M. purpurascens (Krombh. ex Boud.) Jacquet.] are presented.

The nutritional and cultural conditions in shake flask culture for improved production of L-Asparaginase from endophytic fungus Fusarium sp. LCJ324: A sequential statistical method

Elangovan Udayan, Anbarasu Kathiravan, John Joel Gnanadoss — Mon, 20 Mar 2023 00:00:00 +0100

L-Asparaginase has a greater demand due to its potential application in the food industry as well as in the pharmaceutical industry. To meet this demand, optimization of nutritional as well as physical conditions is critical for scaling up the production of L-Asparaginase. This study aims to achieve enhanced L-Asparaginase production, a therapeutic enzyme from the endophytic fungus Fusarium sp. LCJ324 isolated from Glycosmis mauritiana (Lam.) Tanaka belonging to the Rutaceae family. Fusarium sp. LCJ324 exhibited L-Asparaginase activity of 8.75 ± 0.55 U mL^-1 in modified Czapek Dox broth, the highest among all the seven different media tested by submerged fermentation. Different sources and concentrations of carbon, nitrogen and amino acid inducers (nutritional factors) as well as pH and temperature (physical parameters) were optimized to achieve enhanced L-Asparaginase production. Maximum L-Asparaginase activity of 19.94 ± 0.35 U mL^-1 was obtained at 30º C with dextrose (3 g L^-1), ammonium sulphate (30 g L^-1), and L-Asparagine (20 g L^-1) at pH 6. Response Surface Methodology was employed for statistical optimization of minimum and maximum levels of the selected parameters. The levels of parameters suggested by the response surface methodology for maximum production of L-Asparaginase were similar to the conventional optimization. A 2.29 fold increase in L-Asparaginase production was obtained through conventional and statistical optimization.