Paper
Green Chemistry
cells mL−1 were added into the S. elongatus cultures. HEPES The cell density and pH of the cultures were monitored for the
(10 mM, pH 7.5) was added to maintain a suitable pH for the next few days.
growth of K. pneumoniae. NH4Cl was used as the nitrogen
source for K. pneumoniae. Growth of K. pneumoniae was moni-
tored by plating serial dilutions on Luria-Bertani (LB) agar
Acknowledgements
supplemented with 100 μg mL−1 ampicillin, which inhibits
the growth of S. elongatus but does not inhibit the growth of This work was partially supported by the Chinese National
K. pneumoniae.
Program for High Technology Research and Development
(2011AA02A207). The authors acknowledge the National Basic
Research Program of China (2011CBA00800) from the Ministry
of Science and Technology of China and a grant from the
1,3-PD fermentation by K. pneumoniae using glycerol
produced by S. elongatus
The cultures of strain YW1 were centrifuged for 5 min at National Natural Science Foundation of China (31100078).
12 000g. The supernatant was collected and concentrated 10-
fold by rotary evaporation to increase the concentration of gly-
cerol to about 10 g L−1. The concentrated glycerol produced by
S. elongatus was then used as the solo carbon source for
Notes and references
K. pneumoniae. Pure glycerol was used as a control. The medium
used for glycerol fermentation by K. pneumoniae contained 5 g
L−1 yeast extract, 10 g L−1 K2HPO4·3H2O, 2 g L−1 KH2PO4, 1 g
L−1 NH4Cl, 0.1 g L−1 MgSO4·7H2O, 30 mg L−1 FeCl3·6H2O,
5 mg L−1 CoCl2·6H2O, and 10 g L−1 pure glycerol or concen-
trated glycerol produced by S. elongatus. K. pneumoniae was
incubated at a shaker speed of 200 rpm at 37 °C. Growth of
K. pneumoniae was monitored by measuring the optical density
at 620 nm.
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Green Chem.
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