Prospecting In Vitro Antioxidant and Photoprotective Properties of Rosmarinic Acid in a Sunscreen System Developed by QbD Containing Octyl p-Methoxycinnamate and Bemotrizinol

Abstract

Progressively growing diagnoses of skin cancer trigger public health concerns about excessive sun exposure, awareness of the deleterious effects of ultraviolet (UV) radiation on the skin, and the proper use of sunscreens. Studies show that bioactive molecules, such as rosmarinic acid (RA), may potentiate the photoprotective and antioxidant activity of topical formulations. This research presents the application of the concepts of quality by design (QbD) to evaluate the critical parameters of quality and the development of an optimized cosmetic formulation with RA by means of an understanding of product design space. Samples were developed using design of experiments (DoE) and they were evaluated for in vitro antioxidant activity and photoprotective efficacy, as well as for photostability through artificial irradiation. We were able to achieve the RA performance regarding antioxidant and SPF properties through in vitro experiments. We obtained the equations for predicting the in vitro antioxidant activity and SPF. Considering our sunscreen system, developed with octyl p-methoxycinnamate and bemotrizinol, the presence of RA increased its antioxidant capacity; however, the in vitro SPF was reduced when both UV filters were used. The development of multifunctional sunscreens is of utmost importance; moreover, there is a need for the rational development of formulations that ensure representative statistical tests of the effects and interactions among the components of a formulation on the desired critical quality attributes, including efficacy.

Rosmarinic Acid Multifunctional Sunscreen: Comet Assay and in Vivo Establishment of Cutaneous Attributes

“…Considering this phenomenon, the association of antioxidants in photoprotective formulations can optimize skin protection. RA is known for its antioxidant potential by free radical scavenging action proven by several experimental protocols, like, DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging and TBARS (malonyl dialdehyde formation) [14,18,37,38]. Its molecule presents two catechol structures conjugated with a carboxylic acid group as an important structural element in the antioxidant activity of this compound [38,39].…”

“…Four formulations containing commercially available octyl p-methoxycinnamate (UVB filter), bemotrizinol (broad spectrum filter), plus 1.0% (w/w) of the bioactive compound rosmarinic acid were used in the study [18]. Formulations' active ingredients are presented Table 1 S1 (Supplementary Materials).…”

“…The daily topical application of sunscreens can protect the skin from UV rays and, thus, delay or reduce the occurrence of skin damage, such as the appearance of melanomas, spots and wrinkles. Considering that antioxidants are capable of helping to minimize the occurrence of ROS, that are related to the damages previously mentioned, the association of such molecules to the photoprotective formulations optimizes the beneficial effects of these products on the skin [9,14,15,17,18].…”

Modulating the Photostability of (E)-Resveratrol in Grape Cane Extract Formulations

“…Bemotrizinol is a molecule which has a structure that includes two hydroxyl groups and one hydroxyphenyl triazine group, enabling tautomerism, a process that facilitates the rapid release of energy after the absorption of UV radiation. 33 Despite these properties, bemotrizinol showed only a slight decelerating effect on the (E)-resveratrol decay. Conceivably, total bemotrizinol solubility was not achieved in our experiments, as this molecule is lipophilic.…”

Dietary Supplements and the Skin: Focus on Photoprotection and Antioxidant Activity—A Review

“…Rosmarinic acid, or (R)-1-carboxy-2-(3,4-dihydroxyphenyl) ethyl ester of 3,4-dihydroxy cinnamic acid, is an ester of caffeic acid and 3,4-dihydroxyphenylacetic acid, being found in plants, such as rosemary ( Rosmarinus officinalis ). The molecular structure of the molecule is represented in Figure 1 [ 15 , 16 , 17 ].…”