Isolation of Endopyhtic and Xylanolytic Bacillus pumilus Strains from Zea mays

Abstract

In this study, two endophytic xylanolytic bacteria, named M1 and M2, were isolated from surface sterilized Zea mays stern and leaf, respectively. Isolates were identified as Bacillus pumilus. Microorganisims showed different morphology on agar plates. Xylanase production level and profile varied between isolates, as well. Maximum xylanase production level of 188.0 ± 20.0 and 5.6 ± 1.1 U/ml were achieved by Bacillus pumilus M1 and Bacillus pumilus M2 in a liquid medium containing 3% corn cobs as a sole carbon source and inducer, respectively. Isolates produced very low level of cellulase in crude enzyme extract. B. pumilus M1 xylanase was partially characterized. Enzyme had a maximum activity at pH 8.0 and 65°C, seemed proper for pulp and paper industry, and required further characterization. In conclusion, this study indicated that inside part of Zea mays is a novel and good source for isolating xylanase producers. After detailed characterization, such enzymes could be used in various applications in paper and pulp, textile, food and feed industries.Key Words: Bacillus pumilus, endopyhte, plant, xylan, xylanase producers. Zea mays'dan Endofitik ve Ksilanolitik Bacillus pumilus Suş ları n ı n İzolasyonuÖz: Bu çal ışmada, yüzey sterilizasyonu yap ı lm ış Zea mays gövde ve yapraklar ı ndan, s ı ras ı ile M1 ve M2 olarak isimlendirilen iki tane endofitik ksilanolitik bakteri izole edilmi ştir. Izolatlar Bacillus pumilus olarak tan ı mlanm ıştı r. Mikroorganizmalar agar üzerinde farkl ı morfoloji sergilemi ştir. Izolatlar aras ı nda, ksilanaz üretim seviyesi ve profilinde de farkl ı l ı klar bulunmaktad ı r. İçinde %3 m ı s ı r koçan ı n ı tek karbon kaynağı olarak bulunduran s ı v ı besi yerinde, Bacillus pumilus Mi ve Bacillus pumilus M2 s ı ras ı ile maksimum ksilanaz aktivitesi olan 188.0 ± 20.0 ve 5.6 t 1.1 U/mi değ erlerine ula şabilmi ştir. İzolatlar, kaba fermentasyon özütünde çok dü ş ük miktarda selülaz üretmi ştir. B. pumilus M1 ksilanaz ı k ı smi karakterize edilmi ştir. Enzim pH 8.0 ve 65°C'de maksimum aktivite götermi ş , ka ğı t beyazlatma endüstrisine uygun görülmü ş ve ileri derecede karakterizasyona ihtiyaç duymu ştur. Sonuç olarak, bu çal ış ma Zea mays' ı n iç k ı sm ı n ı n, ksilanaz üreticilerinin izolasyonu için yeni ve iyi bir kaynak oldu ğ unu göstermi ştir. Detayl ı tan ı mlama ard ı ndan bu enzimler, ka ğı t, tekstil, g ı da ve yem endüstrisinde çe ş itli uygulamalarda değerlendirilebilmesi mümkündür.

A Novel Triculture System (CC3) for Simultaneous Enzyme Production and Hydrolysis of Common Grasses through Submerged Fermentation

“…Recently, Compant et al ( 2005 ), showed that cell wall degrading enzymes, endogluconase and polygalacturonase are required for immigration of Burkholderia sp in Vitis vinifera . There are few reports on the application of endophytic bacteria having potential of hydrolytic enzymes production (Lima et al, 2005 ; Yasinok et al, 2008 ; Xiong et al, 2013 ). However, there is no report on endogenous bacteria associated with perennial grasses having potential for biomass degradation.…”

A novel and cost effective methodology for qualitative screening of alkalo-thermophilic cellulase free xylano-pectinolytic microorganisms using agricultural wastes

“…1b), where as, an isolate giving no zone of clearance on nutrient-agar plate containing wheatbran, did not show any zone of substrate clearance on nutrient-agar plate containing birchwood xylan ( Table 1). Use of commercial xylan containing nutrient agar plates for the screening of xylanase producing strains through the formation of zone of substrate hydrolysis have been reported by several workers (Gessesse and Gashe 1997;Cordeiro et al 2002;Nair et al 2008;Yasinok et al 2008;Gupta et al, 2009). In secondary screening, colonies showing no zone of clearance on wastepaper-nutrient agar medium were specified to be the cellulase free microorganisms.…”

“…The earlier studies concentrate on low cost enzyme production rather than cost effective screening. Literature has shown the use of xylan (Nair et al 2008;Yasinok et al 2008;Gupta et al 2009), pectin (Boccas et al 1994;Mellon and Cotty 2004;Ahlawat et al 2007), and cellulose (Baharuddin et al 2010) for screening purposes. The use of these purified substrates would be too expensive for qualitative estimation of enzyme activity during screening.…”

Screening and Molecular Identification of New Microbial Strains for Production of Enzymes of Biotechnological Interest

“…In primary screening, formation of a clear zone around the colonies, after Congo red staining of nutrient agar medium containing xylan, indicated the colonies which were the xylanase producers. The use of commercial xylan containing nutrient agar plates for the screening of xylanase producing strains through the formation of zone of substrate hydrolysis have been reported by several works (Gupta et al 2009;Nair et al 2008;Yasinok et al 2008). In a secondary screening, colonies of different isolates showing zone of clearance on pectin-nutrient agar medium were specified to be the pectinase microorganisms.…”