Quantification and characterization of the phenolic compounds of kenaf leaves

Dissertation for the Master Degree in Technology and Food Security

In the food industry is necessary to bring new ways to improve the taste and quality of food and add health benefits for the consumer, some herbs and plants are a good natural source of antioxidants having the ability to protect the human system from many chronicle diseases, such as Parkinson and inflammatory processes. Combining these two worlds there is a way to acquire a new product. To know if the plant chosen is suitable to be a future add to a certain food it’s necessary to study the components of the plant and determinate the quantitative and qualitative composition of the metabolite group of interest, in this case phenolic compounds. The plant of interest was Hibiscus cannabinus L. (Kenaf), from Malvaceae family that it’s known for its fibres but it is also used as an infusion or condimental herb and in traditional medicine as an antidote to poisoning with chemicals and venomous mushrooms, it’s known in Asia and Africa but still barely approached by European countries. In order to separate and identify the phenolic compounds a liquid extraction with a polar solvent was the first step, it was chosen MeOH/H2O and MeOH (80% w/w; 100%). Was determinate the antioxidant capacity and the quantification of the phenolic content of the plant samples, for Everglades 41 the DPPH value of Ec50 was 27,33, The ORAC value was 1273,7 (μmol Trolox/mg sample) and the Folin-Ciocalteu 26,40 EAG (mg)/Sample (g)). For the Tainung 2 type was 43,00, 307.54 and 18,67, respectively. The final step was the identification of the compounds by liquid chromatography followed by mass spectrometry with time of fly analyzer and quadrupole time of fly (HPLC-ESI-MS), were obtained 47 compounds for Everglades leaf and 37 for Tainung 2.