Table 1.

Thickness and cell density of cellulolytic biofilms cultivated with various types of feedstock and microorganisms

No.	Substrate	Culture	Thickness	ρa (cells cm-2)	d (μm)	Microscope	ρv (cells cm-3)	Reference
1	Alfalfa leave	Mixed rumen bacteria	Monolayer	2.12 × 108	0.77	TEM	2.74 × 1012	(Cheng et al. 1984)
2	Forage	Fibrobacter succinogenes	Monolayer	9.68 × 107	1.15	SEM	8.43 × 1011	(Weimer et al. 1993)
3	Wheat straw	Fibrobacter succinogenes Butyrivibrio fibrisolvens	Monolayer	6.85 × 107	1.36	SEM	5.02 × 1011	(Miron et al. 2001)
4	Cellulose	Land fill mixed culture	Monolayer	2.02 × 107	2.51	Confocal	8.05 × 1010	(Burrell et al. 2004)
5	Wheat embryo	Agrobacterium tumefaciens	Monolayer	5.29 × 107	1.55	SEM	3.41 × 1011	(Mooney and Goodwin 1991)
6	Cellulose	Mixed leachate	Monolayer	2.53 × 107	2.25	SEM	1.13 × 1011	(Song et al. 2005)
7	Cellulose	C. obsidiansis	~ 10 μm	1.69 × 108	1.80	Confocal	1.69 × 1011	This study