Analyte Analytical method Linear range LOD Recovery (%) Ref Proline Colorimetry 0-200 mg/L - 96-106 [65]   Colorimetry 0.1-36 μmoles/g fresh wt - - [64]   HPLC-MS 0.3125-10 mol L−1 0.4 μM (LOQ) 85-122 [32]   HPLC-ELSD 25-500ppm 1.08×10-4μmol   [6]   CE-UV 0.1 mM-100 mM 0.1 mM 90-101 [35]   GCMS     90 [70]       0.001 μM   [61]   CE-UV 5-100 mg/L 11.6 μM 85 [7] Betaine Colorimetry   NG 90-95 [99]   Colorimetry 1-5 mg/mL - ͂ 100 [103]   Thin layer electrophoresis+scanning reflectance densitometry   10 μg/20 μL - [39]   GC-pyrolysis 20-150 nmol   78.4 [41]   HPLC-UV   0.0005 μM   [61]   HPLC-UV - - 95 [58]   HPLC-UV 15-650 μg/mL 15 μg/mL 79.7 [108]   HPLC-MS 0.3-10 mol L−1 0.3 μM (LOQ) - [32]   HPLC-ELSD 10-250 μg/mL 3 μg/mL 98-102 [97]   HPLC-ELSD 25-500ppm 7.81×10-5μmol - [6]   CE-UV 0.1 mM-100 mM 0.1 mM 102-110 [35]   CZE-UV 0.050-5.0 mM 0.010 mM 94 [114]   CE-UV 5-100 mg/L 28.3 μM 90-92 [7] Mannitol GCMS     108 [70]   HPLC-UV   0.0025 μM   [61]   HPLC-ELSD 25-500ppm 1.43×10-4μmol   [6]

Table 3: Linear range, LOD and recovery data reported for proline, betaine and mannitol selected analytical methods of proline, betaine and mannitol.