Standards | Regression equations |

Vanillic acid | Y = 1.0138x − 0.0071 (R |

Catechol | Y = 1.9037x − 0.013 (R |

Gallic acid | Y = 1.3595x − 0.003 (R |

Chlorogenic acid | Y = 0.66x + 0.00002 (R |

Ferulic acid | Y = 0.7564x + 0.1046 (R |

2 phenolics | Y = 1.5532x + 0.0318 (R |

3 phenolics | Y = 1.7526x + 0.0421 (R |

4 phenolics | Y = 1.8556x − 0.0509 (R |

5 phenolics | Y = 1.5237x − 0.0226 (R |

7 phenolics | y = 0.8773x − 0.0625 (R |

9 phenolics | y = 1.0022x − 0.1866 (R |

11 phenolics | y = 0.7771x − 0.0751 (R |