{ diff(x1, t) = (1*k30*k1*x2/(k2 + x2)*x1/(k3 + x1) + 1*k30*k4*x2/(k2 + x2) + 1*k30*k5*x3*x4/(k6 + x4) + 1*k30*k7*x5*x4/(k8 + x4) + (-1)*k30*k9*x1 + (-1)*k30*k10*x1*x6)/k30,
  diff(x2, t) = ((-1)*k30*k16*x7*x2/(k2 + x2) + 1*k30*k13*k31/(k14 + k31) + (-1)*k30*k15*x2)/k30,
  diff(x3, t) = ((-1)*k30*k20*x7*x3/(k6 + x3) + 1*k30*k17*k31/(k14 + k31) + 1*k30*k18*x2/(k2 + x2) + (-1)*k30*k19*x3)/k30,
  diff(x4, t) = ((-1)*k30*k5*x3*x4/(k6 + x4) + (-1)*k30*k7*x5*x4/(k8 + x4) + 1*k30*k10*x1*x6 + (-1)*k30*k29*x4)/k30,
  diff(x5, t) = ((-1)*k30*k23*x7*x5/(k8 + x5) + 1*k30*k21*x1/(k3 + x1) + (-1)*k30*k22*x5)/k30,
  diff(x6, t) = ((-1)*k30*k10*x1*x6 + 1*k30*k24 + 1*k30*k25*x9/(k26 + x9) + (-1)*k30*k27*x6 + (-1)*k30*k5*x3*x6/(k6 + x6) + (-1)*k30*k7*x5*x6/(k8 + x6))/k30,
  diff(x7, t) = (1*k30*k11*x1/(k3 + x1) + (-1)*k30*k12*x7 + (-1)*k30*k16*x7*x2/(k2 + x2) + (-1)*k30*k20*x7*x3/(k6 + x3) + (-1)*k30*k23*x7*x5/(k8 + x5))/k30,
  diff(x8, t) = 0,
  diff(x9, t) = (1*k30*k5*x3*x4/(k6 + x4) + 1*k30*k7*x5*x4/(k8 + x4) + (-1)*k30*k25*x9/(k26 + x9) + 1*k30*k5*x3*x6/(k6 + x6) + 1*k30*k7*x5*x6/(k8 + x6) + (-1)*k30*k28*x9)/k30 }