Ollagen/melissa.Figure four. AFM visualization of collagen film (the roughness parameters have been calculated from ten ten scanned areas).Figure 5. AFM visualization of Col/ML film (the roughness parameters had been calculated from ten 10 scanned places).three.four. Mechanical Properties Tensile strength of collagen and melissa-incorporated collagen films have been examined (Table 2). The arithmetic imply from seven samples was correctly assessed for collagen film (41.7 MPa) and melissa-incorporated collagen film (9.eight MPa), which indicates that the addition of melissa decreases the mechanical properties of collagen films.Cosmetics 2021, 8,9 ofTable 2. Mechanical properties of collagen and melissa-incorporated collagen film. Material Collagen Collagen/Melissa Fmax (MPa) 41.7 9.31 9.eight six.16 Emod (GPa) 0.627 0.08 0.321 0.According to mechanical properties measurement, the Young modulus was calculated. Benefits are presented in Table two. The mean average with the Young modulus for collagen film was 0.627 GPa, whereas for melissa-incorporated collagen film it was 0.321 GPa. Tensile stiffness is weaker in collagen film with the addition of melissa. The reduce on the mechanical properties of collagen films after melissa addition indicates that the structure from the material has been changed. Mechanical properties of collagen film modified with melissa extract are significantly worse than for pure collagen films. It might suggest that hydrogen bonds involving components of melissa extract are stronger than hydrogen bonds amongst melissa extract and collagen. The above outcomes show that the addition of melissa to collagen will not improve the mechanical properties of collagen film. Having said that, melissa is known for its Cucurbitacin D Epigenetics antioxidant properties [53,54]. Inside the next step, the antioxidant properties of melissa-incorporated collagen films were assessed. 3.5. Determination of Antioxidant Capacity 3.five.1. Spectrophotometric Process for Determination of the Total Polyphenols Content of Utilizing the Folin Blebbistatin MedChemExpress iocalteu Reagent (F Approach) The Folin iocalteau process is applied to decide the content of phenolic compounds. The phenolic concentration can be read in the gallic acid (or caffeic) calibration curve, which can be utilised as the phenol reference standard [55]. The reaction of gallic acid with molybdenum, a component of the Folin iocalteu reagent, is presented in Figure 6.Figure six. Reaction of gallic acid with molybdenum, a element of the Folin iocalteau reagent [55].It really is a very simple and sensitive process; nevertheless, it is not selective, and the reaction is slow at low pH. The Folin iocalteau reagent can react with many compounds contained within the sample, in particular sugars, aromatic amines, sulfur dioxide, ascorbic acid, and a lot of other phenolic and non-phenolic compounds (e.g., amino acids, hydrazine, proteins, urea), which could ultimately influence the final result of the evaluation of polyphenolic compounds [55,56]. Probably the most crucial stage in this method is preparation a right calibration curve for the experiment. For the Folin iocalteu process, the data obtained for the calibration curve are collected in Table three. Determined by the obtained outcomes, a common curve was drawn as the dependence with the absorbance value on the concentration of caffeic acid (Figure 7).Cosmetics 2021, 8,10 ofTable three. Data obtained for the calibration curve. Caffeic acid volume (mL) Concentration (mg/L) Absorbance 0.10 0.50 0.101 0.20 0.ten 0.169 0.30 0.15 0.241 0.50 0.25 0.388 0.60 0.30 0.457 0.70 0.35 0.539 0.80 0.40 0.Figure 7. The calibr.
