Release of bioactive substances from formulations containing Arthrospira platensis (Spirulina platensis)

Abstract

Arthrospira platensis (Spirulina platensis) is a well-known microalga and has been utilized as a medicinal agent and foodstuff by humans since at least 16th century. The aim of this study was to determine zinc content as well as determine phenolic and indole compounds from commercial preparations containing Arthrospira platensis (lyophilizate, tablets, and capsules) before and after extraction with methanol and incubation with artificial digestive juices. The secondary aim of this study was to evaluate the quality of these preparations. The samples were incubated in artificial stomach juice and in intestinal juice. The samples were mineralized and their zinc(II) ions content was estimated using flame absorption atomic spectroscopy (F-AAS). The maximum zinc(II) ions content released into the digestive juices was found to be up to 1.6 mg/100 g of the preparation. Phenolic compounds identified in the examined extracts are as follows: gallic acid; protocatechuic acid; 3,4-dihydroxyphenylacetic acid; p-hydroxybenzoic acid; syringic acid; cinnamic acid; and quercetin. Furthermore, indole compounds identified were 5-hydroxy-L-tryptophan, 5-methyl-L-tryptophan, L-tryptophan, tryptamine, and 5-methyltryptamine. Consequently, it was also found that the distributed Arthrospira platensis in the form of tablets does not disintegrate in the artificial digestive juices. Among the examined preparations, only hard capsules met the requirements of the European Pharmacopeia 8th ed.