plants Article Determination of Phenolic Content, Antioxidant Activity, and Tyrosinase Inhibitory Effects of Functional Cosmetic Creams Available on the Thailand Market Sariya Mapoung 1,2 , Warathit Semmarath 1 , Punnida Arjsri 1 , Sonthaya Umsumarng 2,3 , Kamonwan Srisawad 1 , Pilaiporn Thippraphan 1 , Supachai Yodkeeree 1,2 and Pornngarm Limtrakul (Dejkriengkraikul) 1,2, *   Citation: Mapoung, S.; Semmarath, W.; Arjsri, P.; Umsumarng, S.; Srisawad, K.; Thippraphan, P.; Yodkeeree, S.; Limtrakul (Dejkriengkraikul), P. Determination of Phenolic Content, Antioxidant Activity, and Tyrosinase Inhibitory Effects of Functional Cosmetic Creams Available on the Thailand Market. Plants 2021, 10, 1383. https://doi.org/10.3390/ plants10071383 Academic Editor: Adam Stebel Received: 7 June 2021 Accepted: 4 July 2021 Published: 6 July 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand; srmapoung@gmail.com (S.M.); warathit_semmarath@cmu.ac.th (W.S.); punnida_dream@hotmail.com (P.A.); k.srisawad@gmail.com (K.S.); tipprapant@gmail.com (P.T.); yodkeelee@hotmail.com (S.Y.) 2 Center for Research and Development of Natural Products for Health, Chiang Mai University, Chiang Mai 50200, Thailand; sonthaya.u@cmu.ac.th 3 Department of Veterinary Biosciences and Veterinary Public Health, Division of Veterinary Preclinical Sciences, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai 50200, Thailand * Correspondence: pornngarm.d@cmu.ac.th or pdej@hotmail.co.th Abstract: Recently, the global trend toward the use of natural extracts and antioxidant agents in the cosmetic cream industry to produce whitening effects has been increasing. This has also been a persistent trend in Thailand. In this study, samples of commercial cosmetic creams on the Thai market were assessed for a functional evaluation of their antioxidant activity, tyrosinase inhibitory effects, and phenolic contents. Samples were extracted using hot water and sonication extraction method to obtain the functional cream extracts. Total phenolic contents in all samples were within the range of 0.46–47.92 mg GAE/30 g cream. Antioxidant activities of the cream extracts were within the range of 3.61–43.98 mg Trolox equivalent/30 g cream, while tyrosinase inhibition activities were within the range of 2.58–97.94% of inhibition. With regard to the relationship between the total phenolic content and the antioxidant activity of the cosmetic creams, Pearson’s correlation coefficient revealed a moderately positive relationship with an r value of 0.6108. Furthermore, the relationship between the antioxidant activity and the tyrosinase inhibitory activity of the cosmetic creams was highly positive with an r value of 0.7238. Overall, this study demonstrated that the total phenolic contents in the functional cosmetic creams could play a role in antioxidant activity and anti-tyrosinase activities. The findings indicate how the whitening and antioxidant effects of cosmetic creams could be maintained after the products have been formulated, as this concern can affect the consumer’s decision when purchasing cosmetic products. Keywords: whitening cream; plant phenolics; cosmetic plants; cosmetic products; hot water cream extraction; Thailand 1. Introduction During the first decade of the 21st century, cosmetic product sales underwent fairly significant growth and represented 23% of the overall market share of consumer products. This growth was driven primarily by the Asian market [1,2]. Among these cosmetic products, the facial and skincare market has accounted for two thirds of total cosmetic sales. Interestingly, a particular aspect of the Asian skincare market would be the prominence of face-whitening products, as pale skin continues to be considered a beauty ideal in Asia [3,4]. Consequently, there has always been a strong demand for skin whiteners throughout the Asian continent [5,6]. Likewise, consumer demand continues to increase for the innovative uses of natural compounds to treat skin aging manifestations including wrinkles, sagging skin, skin texture changes, and hyperpigmentation [7–10]. Accordingly, cosmetic manufacturers have begun Plants 2021, 10, 1383. https://doi.org/10.3390/plants10071383 https://www.mdpi.com/journal/plants