生物膜的主要组成成分是（  ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24973' and id < 2127478 and id<>'2127478' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24973' and id > 2127478 and id<>'2127478' order by id asc limit 5