A comparative overview on chili pepper (capsicum genus) and sichuan pepper (zanthoxylum genus): From pungent spices to pharma-foods

Background: Both Chili pepper (CP) and Sichuan pepper (SP) have long been used for culinary purposes throughout Asia. It is well known CP and SP are well accompanied in Sichuan Cuisine, producing a typical pungent sensation. In recent decades, increasing evidences suggest a series of health benefits and pharmacological effects are associated to the two peppers. Now, a systematic comparison of structural and bioactivities diversity of bioactive ingredients from edible parts of two peppers are necessary to address their future application. Scope and approach: Bioactive composition, organoleptic property as well as pharmacological activity in cellular, animal, and human subjects are compared between SP (pericarps and leaves) and CP (fruits). Key findings and conclusions: Both SP and CP are rich in alklyamides, polyphenols, and odorants but their structures are greatly variable. Carotenoids are primarily identified in CP but rather in SP, whereas coumarins are the specific ingredients in SP as compared with CP. Pungent sensations evoked by capsainoids and sanshools are obvious distinct, which is attributed to different mechanisms of interaction with membrane ion channels. Due to these bioactives, especially for capsaicin and hydroxyl-α-sanshool, extracts and purified compounds of CP and SP presented attenuation effects against pain, obesity and hyperlipidemia, diabetes, atherosclerosis, gastrointestinal disorder, tumors, and neurodegenerative diseases even though large-scale and well-designed clinical trials are highly needed. However, more approaches should be conducted to overcome side effects of capsaicin during clinical application. Also, the pharmacological interaction among bioactives in two peppers should be further verified in physiological condition.