Proline Determination in Plant Tissues

Proline is a proteinogenic amino acid which plays distinct roles in plant under a variety of abiotic stress conditions such as drought, salinity, heavy metals, extreme temperatures, and UV-B radiation. The content of proline is closely related to the stress resistance of plants. The overproduction of proline imparts stress tolerance by maintaining cell turgor or osmotic balance; stabilizing membranes thereby preventing electrolyte leakage; and scavenging the reactive oxygen species (ROS) and other free radicals, thus preventing oxidative burst in plants. In addition to the protection of developing cells from osmotic damage, the functions of proline also include stabilizing the structure of biological macromolecules, reducing cytosolic acidity, relieving ammonia toxicity, and maintaining cell redox status.

STEMart is able to efficiently and accurately determine the content of proline in plant tissues to assess the plant resistance against salinity and drought stresses.

Test Samples

Plant tissue

Test Methods

• Acid-ninhydrin method. The reaction of proline with acidic-ninhydrin results in the formation of a stable red-colored compound, which has a peak absorbance at 520 nm.
• Fluorescamine method. The reaction of proline with fluorescamine yields a product, which has a strong absorption at 312 nm.
• Fluorescence competition method. Proline can competitively inhibit the fluorogenic reaction of primary amines with fludescamine. The degree of inhibition is proportional to the amount of proline, and can be measured at Ex/Em = 380/480 nm.
• Isatin paper assay. Isatin is a highly specific color reagent that can bind to proline to form a blue derivative -- pyrrole blue. The intensity of blue color indicates the proline concentration.
• High performance liquid chromatography (HPLC) method. The reaction of 9-fluorenylmethyl-chloroformate (FMOC-Cl) with proline results in the formation of stable and highly fluorescent derivatives. The fluorescence of these derivatives can be detected at Ex/Em = 260/315 nm after separation by HPLC.
• Optical method. The optical method is based on the measurement value angle (α) of the polarization plane of radiation at a certain wavelength λ. When increasing the proline concentration in solution, the angle of the polarization plane will increase. According to the standard curve with known proline concentration within c = (0.001 – 0.1) %, the proline content in the sample can be calculated.

Why Choose Us

• Comprehensive test report including relevant experimental steps, relevant parameters of the experiment, original pictures, original data, and complete experiment results
• Rich experience in proline determination
• Customized service for plant research
• Professional instruments and equipment for reliable data and results
• Rapid turnaround and cost-effective

For more information about our plant proline determination service, please contact us.