Screening, statistical optimized production, and application of β‐mannanase from some newly isolated fungi

Abstract

Eighty‐eight fungi isolated from soil and decaying organic matter were screened for mannanolytic activity. Twenty‐eight fungi produced extracellular mannanase on locust bean gum as evidenced by zone of hydrolysis produced on mannan agar gel. Six prominent producers, including four Fusarium species namely Fusarium fusarioides NFCCI 3282, Fusarium solani NFCCI 3283, Fusarium equiseti NFCCI 3284, Fusarium moniliforme NFCCI 3287 with Cladosporium cladosporioides NFCCI 3285 and Acrophialophora levis NFCCI 3286 produced the β‐mannanase in the range of 84–140 nkat/mL. All these grew well on particulate substrates in solid‐state fermentation (SSF), producing relatively higher titers on mannan‐rich palm kernel cake (PKC) and copra meal. Two high yielding strains, F. equiseti (1747 nkat/gds) and A. levis (897 nkat/gds) were selected for statistical optimization of mannanase on PKC. Interaction of two critical solid state fermentation parameters, pH and moisture on mannanase production by these two molds was studied by response surface method. Optimized production on PKC resulted in three‐ to fourfold enhancement in enzyme yield was observed in case of F. equiseti (5945 nkat/gds) and A. levis (4726 nkat/gds). HPLC analysis of mannan hydrolysate indicated that F. equiseti and A. levis mannanase performed efficient hydrolysis of konjac gum (up to 99%) with exclusive mannooligosaccahride (DP of 4) production. A seminative SDS‐PAGE revealed that A. levis and F. solani produced three isoforms, F. moniliforme produced two isoforms while F. fusarioides, F. equiseti, and C. cladosporioides produced a single enzyme.

Ultrastructural changes in methicillin-resistant Staphylococcus aureus (MRSA) induced by metabolites of thermophilous fungi Acrophialophora levis

“…Likewise, in previous studies Acrophialophora sp. was extensively studied for production of industrial enzyme [ 38 – 43 ] however, no report was present on antibacterial and antioxidant activity. This study reports for the first time, the potential source of anti- S .…”

Effect of Rhizospheric Fungus on Biological Control of Root Rot (Fusarium equiseti) Disease of Saposhnikovia divaricata

“…Antagonistic fungi mainly inhibit plant diseases through competition, lysis, and hyperparasitism [46]. Through the production of β-glucosidase, cellulose, xylanase [47,48], pectolases [49], and β-mannanase [50], the genus Acrophialophora was discovered to effectively inhibit the growth of plant pathogenic fungi. In this study, MR-57 culture filtrate inhibited F. equiseti mycelium and spore germination, resulting in mycelium malformation and rupture and a decreased spore germination rate.…”

Isolation and screening of thermophilic and thermotolerant fungi for production of hemicellulases from heated environments

“…27, 24, 21, and 18 nkat/ml. Soni et al (2016) screened 88 fungi for mannanase activity and found 28 fungi produced extracellular mannanase when LBG used as carbon source in liquid medium. Moretti et al (2012) isolated 27 thermophilic and thermotolerant fungal strains from self-heated habitats and screened for xylanase production.…”