Table 1.

Biological conversions of crude glycerol to chemicals

Product	Pathway	Product productivity	Reference
1, 3-propanediol	Fed-batch cultures of Klebsiella pneumoniae strain	1.7 g/L/h	[6]
	Maximum 1,3-propanediol production from K. pneumonia	13.8 g/L	[29]
	Optimize 1,3-propanediol production from K. pneumoniae ATCC 15380	56 g/L	[30]
	Integrated bioprocess combining biodiesel production by lipase with microbial production of 1, 3-propanediol by K. pneumoniae strain	1.7 g/L/h	[31]
	Clostridium butyricum strain VPI 3266 on a synthetic medium	0.60 mol/mol glycerol	[32]
	C. butyricum strain F2b (process modelling)	NAa	[33]
	C. butyricum VPI 1718; fed-batch operation under non-sterile culture conditions	67.9 g/L	[35]
	One vessel bio- and chemocatalytic process; in a biphasic system without intermediate separation of 1, 3-propanediol; C. butyricum DSM10703	134 m mol/L	[36]
Citric acid	Y. lipolytica strain ACA-DC 50109 (process modelling)	NAa	[33]
	Acetate Mutants of Y. lipolytica Wratislavia AWG7 strain; Fed-batch operation	139 g/L	[39]
	Yarrowia lipolytica strain LGAM S (7)1	35 g/L	[42]
	Y. lipolytica N15	71 g/L	[43]
Erythritol	Fed-batch cultures of Y. lipolytica Wratislavia K1	1 g/L/h	[41]
Hydrogen	Photofermentative conversion process; Rhodopseudomonas palustris strain	6 mol/mol glycerol	[44]
	Enterobacter aerogenes strain HU-101; continuous culture; porous ceramics as a support material to fix cells	63 mmol/L/h	[45]
	Optimize some media compositions of E. aerogenes ATCC 35029	0.85 mol/mol glycerol	[46]
	Anaerobic treatment process; crude glycerol was a co-substrate	2.9 mmol/g glycerol	[49]
Poly (hydroxyalkanoates) (PHAs)	Pseudomonas oleovorans NRRL B-14682 and P. corrugata 388 grew and synthesized PHB and mcl-PHA, respectively	NAa	[52]
	Producing PHB; Paracoccus denitrificans and Cupriavidus necator JMP 134 strains	48%	[53]
	Producing PHB; Cupriavidus necator strain DSM 545	50%	[54]
	Producing PHB; Zobellella denitrificans MW1; fed-batch cultivation	66.9% ± 7.6%	[55]
	Producing PHB; Mixed microbial consortia (MMC)	> 50%	[56]
	Pseudomonas oleovorans NRRL B-14682; batch culture	30%	[57]
Phytase	High cell density fermentations, recombinant Pichia pastoris	1125 U/mL	[70]
Lipase	Staphylococcus caseolyticus EX17	127.3 U/L	[75]
Succinic acid	Basfia succiniciproducens DD1; continuous cultivation process	1.02 g/g glycerol	[68]
Docosahexaenoic acid-rich algae	Fermentation of the alga, Schizochytrium limacinum strain; continuous culture	0.52 g/L-day	[61]
Eicosapentaenoic acid	Fungus Pythium irregulare	90 mg/L	[60]
Lipid	Schizochytrium limacinum SR21; batch culture	73.3%	[62]
	Cryptococcus curvatus; two-stage fed-batch process	52%	[63]
	Oleaginous red yeast Rhodotorula glutinis TISTR 5159; fed-batch fermentation	60.7%	[65]
	Chlorella protothecoides	3 g/L per day	[66]
	Fungi	42.6%	[67]
Recombinant human erythropoietin etc.	Pichia pastoris medium	31 mg/L	[72]
Ethanol	Nonpathogenic Kluyvera cryocrescens S26; batch fermentation	27 g/L	[47]
	Klebsiella pneumoniae mutant strain (GEM167)	21.5 g/L	[48]
Methane	Anaerobic digestion	0.306 m3/kg glycerol	[51]
Butanol	Clostridium pasteurianum (ATCC®6013™)	0.30 g/g glycerol	[71]
Fungal protein	Rhizopus microsporus var. oligosporus	0.83 ± 0.02 g/g glycerol	[77]

^a represents data are not available