TY - JOUR
T1 - Recovery of the fibrolytic microorganisms from rumen fluid by flocculation for simultaneous treatment of lignocellulosic biomass and volatile fatty acid production
AU - Takizawa, Shuhei
AU - Abe, Kenichi
AU - Fukuda, Yasuhiro
AU - Feng, Mengjia
AU - Baba, Yasunori
AU - Tada, Chika
AU - Nakai, Yutaka
N1 - Funding Information:
This work was supported by JSPS KAKENHI [grant nos. JP17H01512 and JP19J12745 ], the Miyagi Prefectural Government Recycling Promotion Division , and the Miyagi Organization for Industry Promotion .
Funding Information:
This work was supported by JSPS KAKENHI [grant nos. JP17H01512 and JP19J12745], the Miyagi Prefectural Government Recycling Promotion Division, and the Miyagi Organization for Industry Promotion.
Publisher Copyright:
© 2020
PY - 2020/6/1
Y1 - 2020/6/1
N2 - Large volumes of rumen fluid are continuously discharged from slaughterhouses, which are typically transported to facilities for treatments of lignocellulosic biomass. Recovery of fibrolytic microorganisms from the rumen fluid enables to reduce the load for wastewater treatment and transportation of rumen fluid. However, there is no standardized method for recovering ruminal microorganisms. Here, we established a flocculation-based method with an optimized flocculant concentration required to recover ruminal microorganisms with fibrolytic activity. Rumen fluid was flocculated with poly-ferric sulfate at 0.4%, 0.7%, 1.0%, and 2.0% and with an inorganic neutral flocculant at 13.0%. Poly-ferric sulfate at 0.4%, 0.7%, and 1.0% effectively recovered ruminal microorganisms, which resulted in an 85.6%, 77.3%, and 75.6% reduction in rumen fluid volume, respectively. These recovered microorganisms retained the endoglucanase activity at 52 kDa and 53 kDa in size. In addition, recovery of ruminal microorganisms allowed for substantial reductions in the solids and organic compound concentrations of the filtrates after the flocculation. As a practical demonstration of this method, tomato leaves were treated with the flocculated rumen fluid at 37 °C for 48 h. Hydrolysis of the tomato leaves using the rumen fluid flocculated with 0.7% poly-ferric sulfate demonstrated elevated endoglucanase activity at 37 kDa, 46 kDa, 57 kDa, 61 kDa, and 66 kDa in size during treatment. Therefore, 0.7% poly-ferric sulfate is the optimal concentration for recovering ruminal microorganisms while maintaining their fibrolytic activity. This is the first study which suggest a novel method to efficiently recover ruminal microorganisms from huge amounts of rumen fluid offers a practical and sustainable solution to reduce the load for wastewater treatment at slaughterhouses and in the transportation of rumen fluid.
AB - Large volumes of rumen fluid are continuously discharged from slaughterhouses, which are typically transported to facilities for treatments of lignocellulosic biomass. Recovery of fibrolytic microorganisms from the rumen fluid enables to reduce the load for wastewater treatment and transportation of rumen fluid. However, there is no standardized method for recovering ruminal microorganisms. Here, we established a flocculation-based method with an optimized flocculant concentration required to recover ruminal microorganisms with fibrolytic activity. Rumen fluid was flocculated with poly-ferric sulfate at 0.4%, 0.7%, 1.0%, and 2.0% and with an inorganic neutral flocculant at 13.0%. Poly-ferric sulfate at 0.4%, 0.7%, and 1.0% effectively recovered ruminal microorganisms, which resulted in an 85.6%, 77.3%, and 75.6% reduction in rumen fluid volume, respectively. These recovered microorganisms retained the endoglucanase activity at 52 kDa and 53 kDa in size. In addition, recovery of ruminal microorganisms allowed for substantial reductions in the solids and organic compound concentrations of the filtrates after the flocculation. As a practical demonstration of this method, tomato leaves were treated with the flocculated rumen fluid at 37 °C for 48 h. Hydrolysis of the tomato leaves using the rumen fluid flocculated with 0.7% poly-ferric sulfate demonstrated elevated endoglucanase activity at 37 kDa, 46 kDa, 57 kDa, 61 kDa, and 66 kDa in size during treatment. Therefore, 0.7% poly-ferric sulfate is the optimal concentration for recovering ruminal microorganisms while maintaining their fibrolytic activity. This is the first study which suggest a novel method to efficiently recover ruminal microorganisms from huge amounts of rumen fluid offers a practical and sustainable solution to reduce the load for wastewater treatment at slaughterhouses and in the transportation of rumen fluid.
KW - Agricultural residue
KW - Biological treatment
KW - Lignocellulose degradation
KW - Slaughterhouse wastewater
KW - Waste management
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U2 - 10.1016/j.jclepro.2020.120626
DO - 10.1016/j.jclepro.2020.120626
M3 - Article
AN - SCOPUS:85081005140
SN - 0959-6526
VL - 257
JO - Journal of Cleaner Production
JF - Journal of Cleaner Production
M1 - 120626
ER -
