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Table 1 End products from in vitro switchgrass fermentations by mixed ruminal microorganisms in the presence or absence of redox dyes

From: Redox mediators modify end product distribution in biomass fermentations by mixed ruminal microbes in vitro

Product Net umol producta SEDb Model P > F
Methyl viologen (0.5 mM) Neutral red (1.0 mM) Safranin O (1.0 mM) Control (no dye)
Methane 122.1 A 62.1 B 38.5 B 139.2 A 9.9 <0.0001
Acetate 269.8 A 182.0 B 142.9 B 305.6 A 13.7 <0.0001
Propionate 60.4 C 119.7 A 48.0 C 91.0 B 5.0 <0.0001
Butyrate 24.0 B 40.2 AB 48.8 A 38.8 AB 5.9 0.018
Isobutyrate 9.7 A 4.3 B 0.8 C 1.8 C 0.7 <0.0001
Valerate 6.8 B 35.9 A 1.5 C 5.3 BC 1.4 <0.0001
Isoval + 2 MBc 19.1 A 14.4 B 0.1 C 1.4 C 1.0 <0.0001
Caproate 6.7 A 8.1 A 0.3 B 2.1 B 1.6 0.003
Total VFA 399.1 A 404.1 A 242.3 B 441.5 A 15.4 <0.0001
Total VFA-C 1025.6 B 1201.3 A 629.6 C 1,092.0 AB 40.5 <0.0001
ACLd 2.58 B 2.97 A 2.61 B 2.42 C 0.04 <0.0001
Enthalpy of combustion, kJ 0.602 B 0.667 A 0.343 C 0.633 AB 0.009 <0.0001
  1. Vials contained 100 mg switchgrass and 3.0 mL of diluted mixed ruminal inoculum in a total liquid volume of 10 mL.
  2. aValues are least-square means from triplicate cultures after 72 h incubation, after correction for inoculated blank vials lacking switchgrass. Values within row having different letters (A, B, C) differ (P < 0.05).
  3. bPooled standard error of the difference.
  4. cIsovalerate plus 2-methylbutyrate (chromatographically co-eluting isomers).
  5. dAverage chain length of VFA.