Tyrosinase inhibitory activity of Sargassum fusiforme and characterisation of bioactive compounds

Abstract

IntroductionSargassum fusiforme (Harvey) Setchell, also known as Tot (in Korean) and Hijiki (in Japanese), is widely consumed in Korea, Japan, and China due to its health promoting properties. However, the bioactive component behind the biological activity is still unknown.ObjectivesWe aimed to optimise the extraction conditions for achieving maximum tyrosinase inhibition activity by using two sophisticated statistical tools, that is, response surface methodology (RSM) and artificial neural network (ANN). Moreover, high‐resolution mass spectrometry (HRMS) was used to tentatively identify the components, which are then further studied for molecular docking study using 2Y9X protein.MethodologyRSM central composite design was used to conduct extraction using microwave equipment, which was then compared to ANN. Electrospray ionisation tandem mass spectrometry (ESI‐MS/MS) was used to tentatively identify bioactive components, which were then docked to the 2Y9X protein using AutoDock Vina and MolDock software.ResultsMaximum tyrosinase inhibition activity of 79.530% was achieved under optimised conditions of time: 3.27 min, temperature: 128.885°C, ethanol concentration: 42.13%, and microwave intensity: 577.84 W. Furthermore, 48 bioactive compounds were tentatively identified in optimised Sargassum fusiforme (OSF) extract, and among them, seven phenolics, five flavonoids, five lignans, six terpenes, and five sulfolipids and phospholipids were putatively reported for the first time in Sargassum fusiforme. Among 48 bioactive components, trifuhalol‐A, diphlorethohydroxycarmalol, glycyrrhizin, and arctigenin exhibited higher binding energies for 2Y9X.ConclusionTaken together, these findings suggest that OSF extract can be used as an effective skin‐whitening source on a commercial level and could be used in topical formulations by replacing conventional drugs.

RSM- and ANN-Based Multifrequency Ultrasonic Extraction of Polyphenol-Rich Sargassum horneri Extracts Exerting Antioxidative Activity via the Regulation of MAPK/Nrf2/HO-1 Machinery

“…The literature showed that phenolic acids lose certain fragments such as methyl (15 Da), hydroxyl (18 Da), and carboxyl (44 Da) during the collision, which helped in determining the compounds [ 3 ]. Compounds 1 – 14 have been tentatively identified in Sargassum fusiforme based on previously reported fragmentation behavior data ( Table 1 ) [ 15 , 16 , 17 , 18 , 19 ]. Interestingly, 5-(3′,5′-Dihydroxyphenyl)-γ-valerolactone 3- O -glucuronide and coumaroylquinic acid were tentatively acknowledged for the first time in optimized MUAE SH extract.…”

“…The RSM–BBD model followed the methodology of Javed et al [ 15 ]. In short, four independent variables—time (X 1 ), temperature (X 2 ), ethanol concentration (X 3 ), and ultrasonic frequency (X 4 )—were checked against four experimental responses—total phenolic content (TPC, Y1), total flavonoid content (TFC, Y 2 ), 1-diphenyl-2-picrylhydrazyl (DPPH, Y 3 ), and 1-diphenyl-2-picrylhydrazyl (ABTS, Y 4 ).…”

“…The hit and trial method was applied to minimize the mean square error, MSE. After constructing the RSM and ANN models, both models were compared using 4 different parameters elaborated by Javed et al [ 15 ], that is, the absolute average deviation (AAD), the standard error of prediction (SEP), the coefficient of determination (R 2 ), and the root mean square error (RMSE). To calculate the optimized condition for the ANN model, a further genetic algorithm (GA) was applied.…”

“…SH extracts were analyzed thrice for their TPC and TFC using the Folin–Ciocalteu test and the aluminum chloride colorimetric method, respectively, by following the method described by Javed et al [ 15 ]. Regression equations (TPC: y = 0.0526x + 0.0020; R 2 = 0.9856, TFC: y = 0.0 336x + 0.0021; R 2 = 0.9894) were derived from calibration curves.…”

Anti-Melanogenic Effects of Takifugu flavidus Muscle Hydrolysate in B16F10 Melanoma Cells and Zebrafish

“…Molecular docking analysis showed that T-6 binds within the TYR cavity, forming hydrogen bonds with Val248, Ala323, Asn320, and Asn81; an ionic bond with Glu322; and engaging in pi-pi stacking interactions with Phe192. The active site of TYR is divided into three distinct regions [35]: a substrate-binding pocket with six histidine residues and a binuclear copper ion; a hydrophobic region comprising Val248, Phe264, Val283, and Pro284; and a solvent-exposed region with Glu189 and Arg268 [36][37][38]. Docking simulations indicated that T-6 may primarily interact with the first and second regions, consequently inhibiting enzyme activity.…”