Renata Miliani Martinez

INTRODUCTION Microalgae are a large group of photosynthetic microorganisms that evolved to tolerate extreme conditions by producing bioactive compounds to protect themselves from environmental stress. Those products, such as polyunsaturated fatty acids (PUFAs), pigments, carbohydrates, vitamins, proteins, peptides, polyphenols and antioxidants, have commercial applications in pharmaceuticals, cosmetics, nutrition, nutraceuticals, nutricosmetics, biopolymers and bioplastics [1-5].

1. Introduction The cosmetic industry has been using natural components in products since the beginning of history. The use of clays in beauty care is old, with therapeutic uses since prehistory [1,2,3]. Reports of treatments with “medicinal earth”, mainly constituted by clay minerals, are present in ancient civilizations’ scriptures, such as ancient China, Egypt, and Greece [2,4]. Nowadays, there is a demand for natural ingredients by consumers, mainly for cosmetic products [5].

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