Table 1.

PHA and hydrogen production by Bacillus thuringiensis on synthetic media

Synthetic mediaa	Glucose (%)	Hydrogen (H2) production stage				PHA production stage
						Effluent from H2 production stage						Fresh GM2 with half bacterial biomassc
		Biogas (ml)	H2			With same bacterial biomass			With half bacterial biomass
			Vol (ml)	%	Yieldb	cdwd	PHBe	NPf	cdw	PHB	NP	cdw	PHB	NP
						mg/l			mg/l			mg/l
	Experiment 1					Experiment 2						Experiment 3
1× + 0.25×	0.5	75	50	66.7	0.36	1660	ndg	195	1200	nd	nd	1680	nd	nd
	1.0	210	130	61.9	0.46	1800	95	nd	1800	110	70	2500	nd	60
	2.0	390	150	38.5	0.27	2000	nd	nd	2400	5	20	2800	80	5
1× + 0.5×	0.5	65	35	53.8	0.26	1090	nd	30	1000	nd	25	1575	nd	60
	1.0	235	160	68.1	0.58	2050	nd	10	1700	50	80	2700	nd	260
	2.0	365	195	53.4	0.35	2000	nd	nd	2000	30	5	3000	10	nd
1× + 1×	0.5	55	35	63.6	0.25	1360	10	40	1260	10	15	1800	15	150
	1.0	185	120	64.9	0.43	2260	15	40	1920	275	80	2600	185	300
	2.0	480	245	51.0	0.42	2200	10	130	2000	100	70	3500	375	190
1× + 2×	0.5	45	30	66.7	0.22	995	nd	35	800	nd	90	1100	nd	145
	1.0	210	145	69.0	0.54	1800	20	5	1000	200	10	2800	325	200
	2.0	230	140	60.9	0.26	3000	nd	nd	3000	50	5	4800	40	15

Values are based on three sets of experiments. Standard deviation was less than 5 %

^aConcentration of M-9+GM-2 medium

^bmol/mol glucose utilized

^cBacterial biomass from the effluent of the H₂ production stage

^dCell dry weight

^ePolyhydroxybutyrate

^fNew co-polymer

^gNot detectable