Identification of Bacillus Species Isolated From Ropey Breads Both With Classical Methods And API Identification Kits

Year 2009, Volume: 22 Issue: 2, 201 - 210, 01.12.2009

F. Erem , M. Certel B. Karakaş

Abstract

In this study, white and whole meal breads baked at laboratory conditions were stored at 37 ºC for 7 days to isolate and identify the Bacillus species responsible for the development of rope spoilage which is the most important bacterial problem in breads. The Bacillus species which were isolated from ropey breads were identified by using classical methods and API identification kits. It was understood that definite identification of some of the isolates using these methods was not possible and these strains could only be identified as being most likely a certain species. Isolates from white bread were identified as B. subtilis, B. megaterium, B. licheniformis, B. coagulans and B. pumilus; and isolates from whole meal bread were identified as B. subtilis, B. megaterium, B. licheniformis using biochemical tests. Using the API identification kits, on the other hand, resulted in the identification of B. licheniformis, B. pumilus, B. subtilis/amyloliquefaciens, ‘most likely’ B. megaterium in white breads and B. licheniformis, B. subtilis/amyloliquefaciens, ‘most likely’ B. megaterium, ‘most likely’ B. thuringiensis and Bacillus spp. in whole meal breads. According to the results of the classical methods B. subtilis was the most abundant species in both white and whole meal breads. API kits, on the other hand, confirmed B. licheniformis as the predominant species.

Keywords

Bacillus, Ropey Bread, Isolation, Identification

Sünmüş Ekmekten İzole Edilen Bacillus Türlerinin Klasik Yöntemler ve API Kitleri ile Tanılanması

Abstract

Bu çalışmada, ekmeklerdeki bakteriyel bozulmaların en önemlisi olan sünme hastalığından sorumlu Bacillus türlerini izole etmek ve tanılamak için normal ve kepekli ekmekler, laboratuvar koşullarında pişirilmiş ve 37 ºC’de 7 gün boyunca muhafaza edilmiştir. Sünmüş ekmeklerden izole edilen Bacillus türleri klasik yöntemler ve API kitleri kullanılarak tanılanmıştır. İzole edilen bazı suşların kesin olarak tanılanmasının bu yöntemlerle mümkün olmadığı, bu suşların ancak muhtemelen tanılanabildiği anlaşılmıştır. Biyokimyasal testler ile normal ekmeklerden izole edilen suşlar B. subtilis, B. megaterium, B. licheniformis, B. coagulans ve B. pumilus; kepekli ekmeklerden izole edilen suşlar B. subtilis, B. megaterium, B. licheniformis olarak tanılanmıştır. API tanılama kitleri kullanıldığında ise tanılama, normal ekmekler için B. licheniformis, B. pumilus, B. subtilis/amyloliquefaciens, muhtemelen B. megaterium; kepekli ekmekler için B. licheniformis, B. subtilis/amyloliquefaciens, muhtemelen B. megaterium, muhtemelen B. thuringiensis ve Bacillus spp. şeklinde sonuçlanmıştır. Biyokimyasal test sonuçlarına göre hem normal hem de kepekli ekmeklerde B. subtilis en fazla bulunan tür olarak belirlenirken; API kitleri ile B. licheniformis’in baskın tür olduğu saptanmıştır

Keywords

Bacillus, Sünmüş Ekmek, İzolasyon, Tanılama

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