Antimicrobial activity and potential of the ingredients of horchata - a traditional southern Ecuadorian highlands herbal drink

Ecuadorian horchata is a herbal mixture infusion; a sweetened compound tisane with ample presence in the gastronomy and ethnopharmacology of the southern Ecuador highlands, particularly in the Loja province. It is composed of a variable number of plant ingredients: herbs, leaves, barks, and flowers, and is served either hot or cold in a variety of settings. Among the medicinal uses of horchata, those of anti-infection are frequent, and there are studies that validate its potency. In this chapter, we review the native species used in the preparation of horchata for their antimicrobial activity and potential. Of the 72 species used in the drink, 35 are native. Of these, ten are insufficiently studied, twenty-one possess some level of antimicrobial activity or toxicity, and three have not been found to exhibit antimicrobial activity. The most studied and used species are Amaranthus hybridus, Amaranthus caudatus - both for their extracts and their starch and film forming properties - and Aloysia triphylla. To a lesser degree, Myrcianthes hallii and Ocimum campechianum have also been studied for their highly active essential oils and extracts in pharmacology and sustainable food packaging and conservation properties. Several species of interest with food preservation antimicrobial properties remain to be studied.