In September 2013, a canker disease of Ficus nitida and F. benjamina was reported for the first time in Assiut governorate, Egypt. Infected samples were collected from various locations. Pure cultures of a fungus were isolated on potato dextrose agar at 25°C from diseased plants. Morphological investigation and DNA sequencing showed that the causal agent was Neoscytalidium dimidiatum. A pathogenicity test conducted using 2-year-old plants of each host gave 70%-80% infection, and the pathogen was reisolated from the inoculated plants. A pure culture of N. dimidiatum was deposited in the culture collection of the Assiut University Mycological Centre (AUMC) under the code AUMC 9293 and the ITS sequence was placed in NCBI under accession number KX985929.

Twenty fungal strains belonging to 17 species and isolated from male scalp hair were tested for their capacity to hydrolyze keratinous material from chicken feather. The identification of the three most efficient species was confirmed by sequencing of the internal transcribed spacer (ITS) region of rDNA. Activities of fungal keratinases produced by Aspergillus stelliformis (strain AUMC 10920), A. sydowii (AUMC 10935), and Fusarium brachygibbosum (AUMC 10937) were 113, 120, and 130 IU mg−1 enzymes, respectively. The most favorable conditions were at pH 8.0 and 50 °C. Keratinase activity was markedly inhibited by EDTA and metal ions Ca+2, Co+2, Ni+2, Cu+2, Fe+2, Mg+2, and Zn+2, with differences between the fungal species. To the best of our knowledge, this is the first study on the activity of keratinase produced by A. stelliformis, A. sydowii, and F. brachygibbosum. F. brachygibbosum keratinase was the most active, but the species is not recommended because of its known phytopathogenicty. Aspergillus sydowii has many known biotechnological solutions and here we add another application of the species, as producer of keratinases. We introduce A. stelliformis as new producer of active fungal keratinases for biotechnological solutions, such as in the management of keratinous waste in poultry industry.

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Cladosporium parasphaerospermum, Cladosporium chlamydosporigenum, and Cladosporium compactisporum have all been discovered and characterized as new Cladosporium species. The three new species seemed to generate cold-active pectinases with high activity at pH 6.0 and 10 °C, pH 6.0 and 15 °C, and pH 5.0 and 15 °C, respectively, with the most active being C. parasphaerospermum pectinase. In submerged fermentation (SmF), C. parasphaerospermum produced the most cold-active pectinase with the highest activity and specific activity (28.84 U/mL and 3797 U/mg) after 8 days. C. parasphaerospermum cold-active pectinase was isolated using DEAE-Cellulose anion exchange resin and a Sephadex G 100 gel filtration column. The enzyme was purified 214.4-fold and 406.4-fold greater than the fermentation medium using DEAE-cellulose and Sephadex G 100, respectively. At pH 7.0 and 10 °C, pure pectinase had the highest activity (6684 U/mg), with Km and Vmax determined to be 26.625 mg/mL and 312.5 U/min, respectively. At 5 mM/mL, EDTA, MgCl2, and SDS inhibited the activity of pure pectinase by 99.21, 96.03, and 94.45%, respectively. The addition of 10 U/mL pure pectinase enhanced the yield of apple, orange, apricot, and peach juice by 17, 20, 13, and 24%, respectively, and improved the clarity and colour of orange juice by 194 and 339%, respectively. We can now add cold-active pectinase production to the long list of Cladosporium species that have been identified. We also report three new species that can be used in biotechnological solutions as active microbial pectinase producers. Although further research is needed, these distinct species might be used to decompose difficult and resistant pertinacious wastes as well as clear fruit juices.

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