Sunlight containing ultraviolet (UV) rays is harmful to human skin health. It can cause cancer, hyperpigmentation, and erythema (1). UV rays reach the Earth's surface, with approximately 95% being UVA, 10% being UVB, and UVC being almost entirely absorbed by the ozone layer (2). Therefore, the use of sunscreen is one of the trendy and attractive solutions (3). Chemical sunscreens have been studied previously and have been found to have relatively high toxicity effects, such as those associated with oxybenzone, ethylhexyl methoxycinnamate, homosalate, and octisalate (4). Natural sources are known to have low side effects. The use of natural sunscreens has become an alternative to replace chemical sunscreens (5). Natural sunscreen can be obtained from marine sources such as artemia, plankton, algae, L. ochroleuca, T. thermophillus ferment, N. gaditana, Spirulina platensis (6)
Brown seaweed (Sargassum sp.) contains flavonoids, alkaloids, terpenoids, tannins, and saponins (7, 8). Previous research has shown that brown seaweed extract has a total phenolic content of 149.04 ± 5.14 mg GAE/g. A concentration of 1.6% brown seaweed extract has a sun protection factor value of 33.2 ± 3.11 (9). Flavonoid compounds have activity as sunscreens. Sun protection factor (SPF) is an indicator used to assess a material's ability to protect the skin from sunlight radiation (10). The SPF value of brown seaweed extract is categorized in the high sun protection product category (SPF > 30) (11). From these various backgrounds, brown seaweed extract needs to be formulated into a sunscreen cream.
The physical properties of the cream are influenced and controlled by the proportion of the emulsifier (12). The use of a combination of stearic acid and triethanolamine as emulsifiers produces a homogeneous and stable cream (13). However, stearic acid and triethanolamine exhibit opposite properties in terms of cream characteristics, including pH value, viscosity, spreadability, and adhesiveness (). Therefore, the proportion of stearic acid and triethanolamine requires further study in brown seaweed extract cream. Simplex lattice design is an optimization method used to determine the optimum formula for a mixture of ingredients (). Optimization of the proportion of stearic acid and triethanolamine in sunscreen cream can be achieved using the simplex lattice design method ().
Declarations
Conflict of Interest
The authors declare no conflict of interest.
Data Availability
The unpublished data is available upon request to the corresponding author.
Ethics Statement
Not applicable.
Funding Information
The author(s) declare that no financial support was received for the research, authorship, and/or publication of this article.
Sunscreen cream containing brown seaweed extract is an alternative to overcome the dangers of UV rays. This study aimed to optimize the stearic acid and triethanolamine content in the brown seaweed extract cream formula using the simplex lattice design method. The optimization responses used were pH, viscosity, spreadability, and adhesiveness. Additionally, evaluating the photoprotective ability requires assessing parameters such as SPF value, erythema transmission percentage (%Te), and pigmentation transmission percentage (%Tp).
Methodology
Materials
Brown seaweed collected from the coast of Suraga Village, Cinangka District, Serang Regency, Banten Province, Indonesia. Etanol 96% (PT. Jayamas Medica Industri Tbk, Indonesia), distilled water (PT. Brataco, Indonesia), triethanolamine (Petronas Chemicals Marketing (Labuan), Ltd., Malaysia), stearic acid (PT. Wilmar Nabati Indonesia), cetyl alcohol (PT. Ecogreen Oleochemicals, Indonesia), glycerin (PT. Wilmar Nabati Indonesia, Indonesia), propylene glycol (SK Picglobal, South Korea), methylparaben (Ueno Fine Chemicals Industry, Ltd., Japan), and propylparaben (Ueno Fine Chemicals Industry, Ltd., Japan).
Preparation of Brown Seaweed Extract
Brown Seaweed dry powder was macerated for 3 days using 96% ethanol (ratio 1:10) with occasional stirring. The extract was concentrated using a rotary evaporator (50 °C, 50 rpm) and a water bath. Remaceration was carried out to obtain maximum extract yield.
Design of Experiment
Optimization of the stearic acid and triethanolamine proportion was conducted using the simplex lattice design approach, employing Design-Expert software version 13 (trial edition). Lower and upper concentration limits were set at 17-19% for stearic acid and 2-4% for triethanolamine. The simplex lattice design experiment process suggested 8 formulas are shown in Table 1. The responses for the optimum formula were pH, viscosity, spreadability and adhesiveness.
Formulation of Brown Seaweed Extract Cream
The oil phase, consisting of stearic acid, liquid paraffin, cetyl alcohol, and propyl paraben, was melted in a beaker and heated on a hot plate at a temperature of 60–70 °C with continuous stirring until a homogeneous mixture was obtained. Simultaneously, the water phase, comprising triethanolamine (TEA), methyl paraben, propylene glycol, and distilled water, was prepared in a separate beaker and stirred until it was uniform. The water phase was then gradually added to the oil phase with constant stirring until a thick cream mass was formed. Once the mixture cooled to approximately 45 °C, brown seaweed extract was incorporated into the cream base with gentle stirring until a homogeneous formulation was achieved.
Physical Evaluation of Brown Seaweed Extract Cream
pH Test
The cream's pH measurement was performed using a calibrated pH meter. The electrode was immersed in the cream, and the pH results were displayed on the pH meter screen (17).
A portion of the cream was placed on a glass object and covered with another glass object. A load of 500 grams was applied to the top glass object and maintained for 5 min to allow adhesion. Subsequently, a load of 80 grams was suspended, creating a downward force that pulled the bottom glass object. The time required for the two glass objects to separate was recorded to evaluate the adhesiveness of the cream (17, 19).
Viscosity Test
Viscosity measurements were performed using a digital Brookfield viscometer (model BDV‑9s). The appropriate spindle was immersed in the cream sample and allowed to equilibrate. Viscosity readings were then recorded directly from the instrument’s display (20).
Simplex Lattice Design Analysis
The simplex lattice design method was employed to optimize the cream formulation by varying the proportions of stearic acid and triethanolamine (14). The measured responses included pH, viscosity, adhesiveness, and spreadability. The lack-of-fit value was used to assess the suitability of the selected model in representing the response data (21). The optimum formulation was predicted based on the desirability value, followed by verification through comparison of predicted and observed results (22). The optimized cream formulation was further evaluated for in vitro photoprotective activity.
SPF=CF×290∑320EE×I×Abs
Equation 1 | CF is the correction factor (set at 10), EE(λ) is the erythemal effect spectrum, I(λ) is the solar intensity spectrum, and Abs(λ) is the absorbance of the sample at each wavelength. The product EE × I is considered constant for each wavelength interval.
The in vitro photoprotective evaluation was conducted by determining the Sun Protection Factor (SPF), the percentage of erythema transmission, and the percentage of pigmentation transmission. The cream was dissolved in 96% ethanol to obtain a 1% solution (23). SPF determination was carried out using UV spectrophotometry, following the method developed by Mansur (24). The absorbance of the sample was measured across wavelengths ranging from 290 to 320 nm at 5 nm intervals (10). SPF values were calculated using Equation 1.
The cream was dissolved in 96% ethanol to obtain a 1% solution. The erythema transmission percentage (%Te) and pigmentation transmission percentage (%Tp) were determined using the equations developed by Cumpelik (25, 26). The %Te was measured over the wavelength range of 292.5–337.5 nm, while the %Tp was measured over 322.5–372.5 nm. These calculations are presented in Equations 2 and 3. In the equations, %Te represents erythema transmission, Fe denotes the flux of erythema (considered constant), and %Tp represents pigmentation transmission.
Results and Discussion
Preparation of Brown Seaweed Extract
Brown seaweeds are distributed globally, with greater abundance in shallow, rocky coastal regions and are typically harvested during low tide (27). Due to their availability and bioactive potential, brown seaweeds have strong prospects for development and industrial applications. In this study, the seaweed was processed into a dry powder to reduce moisture content, thereby inhibiting microbial growth. The powdered form also increases the surface area of the simplicia particles, enhancing solvent contact and penetration, which facilitates the extraction of more compounds. The extraction process yielded 2.34%, which is lower than that reported in previous studies (6.67%) (9). Factors such as extraction temperature, duration, and milling method are known to influence yield (28). The resulting extract exhibited a greenish color, a thick consistency, and a characteristic odor reminiscent of seaweed.
Formulation of Brown Seaweed Extract Cream
All formulations produced homogeneous cream with a green color, a characteristic seaweed odor, and a soft texture. The presence of brown seaweed extract contributed to the cream’s distinctive color and scent. The cream formulation was adapted from previous research with several modifications (29). Stearic acid and triethanolamine were used in combination as emulsifying agents to form a stable oil-in-water (O/W) emulsion. The evaluation of the cream preparation was conducted to ensure compliance with pharmaceutical standards and to assess the quality and suitability of each formulation. These results were further used to identify the optimal formulation of the brown seaweed extract cream. The creams demonstrated good homogeneity, indicated by a uniform color and the absence of visible particles (30). Homogeneity refers to the even distribution of all components within a preparation. It is influenced by factors such as the solubilization of ingredients and the effectiveness of the stirring process, which ensures the active ingredients are uniformly dispersed throughout the cream.
Physical Evaluation of Brown Seaweed Extract Cream
pH Test
The pH of the cream formulation was measured to assess its compatibility with the skin's pH. Creams with low pH values (1-4) can cause skin irritation, while those with high pH values (8-14) may lead to skin dryness. The acceptable pH range for topical creams is 4.5–6.5 (31). The results of the pH measurements are presented in Table 2. Analysis using the simplex lattice design was performed, and the corresponding ANOVA results are shown in Table 3. Based on the ANOVA analysis, a linear model was selected to evaluate the pH response, with a significant p-value of 0.0001 (p < 0.05). The lack-of-fit test yielded a p-value of 0.2628 (p > 0.05), indicating that the model was not significantly different from pure error. Thus, there was no significant discrepancy between the observed and predicted data. The resulting equation from the simplex lattice design is shown in Table 4.
According to the equation, triethanolamine was found to have a dominant effect on increasing the pH compared to stearic acid. The response surface graph is presented in Figure 1, illustrating that increasing the concentration of stearic acid results in a more acidic formulation, while higher levels of triethanolamine yield a more alkaline pH. These findings are consistent with previous research indicating that triethanolamine acts as an alkalizing agent, whereas stearic acid contributes to acidity (32, 33). Chemically, triethanolamine (C₆H₁₅NO₃) contains a tertiary amine functional group, which imparts basic properties (34). In contrast, stearic acid contains a carboxyl group (-COOH), classifying it as a carboxylic acid (35).
Figure 1. Response model of formula containing a mixture of stearic acid and triethanolamine with different ratio. Note: (A) pH, (B) spreadability, (C) adhesiveness, and (D) viscosity.
Table 2. Physical evaluation of brown seaweed extract cream.
Characterization
F1
F2
F3
F4
F5
F6
F7
F8
pH
5.39
5.42
4.86
4.83
6.02
5.96
4.93
5.11
Spreadability (cm)
5.48
5.49
5.17
4.47
5.99
5.69
5.30
5.36
Adhesiveness (second)
7.64
7.51
8.76
8.95
6.71
6.86
8.35
7.71
Viscosity (dPas)
592.26
396.44
990.86
988.82
247.52
203.26
790.53
592.43
Table 3. Results of the p-value model and lack of fit.
Table 6. Prediction and actual verification results.
Response
Prediction
Actual
P-Value
pH
5.878
5.756±0.050
0.840
Spreadability (cm)
5.843
5.680±0.495
1.000
Adhesiveness (second)
6.798
6.798±0.220
0.981
Viscosity (dPas)
216.023
247.926±0.055
1.000
Table 7. Photoprotection evaluation of brown seaweed extract cream.
Evaluation
Result
Categories
SPF
21.679±2.281
High sun protection
%Te
0.636±0.164
Sunblock
%Tp
0.468±0.250
Sunblock
Spreadability Test
The spreadability test was conducted to assess the ability of the cream to spread evenly when applied to the skin (36). Adequate spreadability ensures a uniform distribution of active ingredients on the skin, thereby enhancing their therapeutic efficacy. A linear model was selected to evaluate the spreadability response, as indicated by a significant p-value of 0.0061. The lack-of-fit test yielded a p-value of 0.8933, indicating no significant deviation from pure error and confirming the model's suitability.
According to the model, triethanolamine had a greater influence on increasing spreadability compared to stearic acid. The response surface graph, shown in Figure 1, illustrates that increasing the concentration of stearic acid reduces spreadability, while higher levels of triethanolamine enhance it. These findings align with previous studies, which report that stearic acid decreases spreadability due to its ability to increase viscosity by forming complexes with other formulation components (37). Spreadability is closely related to viscosity—higher viscosity typically results in lower spreading ability. Triethanolamine, being part of the water phase, has a lower viscosity compared to oil components, thereby contributing to improved spreadability (38).
Adhesiveness Test
The adhesiveness test was conducted to determine the duration the cream remains adhered to the skin surface (39). Adequate adhesiveness ensures that the cream remains in place, allowing for prolonged contact with the skin and optimal therapeutic effect. The minimum acceptable adhesion time for topical creams is greater than 4 s. A linear model was selected to evaluate the adhesiveness response, as indicated by a significant p-value of 0.0001. The lack-of-fit test produced a p-value of 0.2267. According to the model, stearic acid was found to be more influential in increasing adhesiveness compared to triethanolamine. Increasing the concentration of stearic acid leads to higher adhesiveness, whereas increasing the concentration of triethanolamine reduces it. Stearic acid, a saturated fatty acid, contributes to the formation of a hydrophobic layer that enhances the cream’s ability to adhere to the skin (40). In contrast, triethanolamine is more hydrophilic (41), which may reduce the cream’s adhesion by promoting faster dispersion or absorption, thereby lowering its retention time on the skin.
Viscosity Test
The viscosity test was conducted to determine the viscosity of each cream formulation, as appropriate viscosity is essential for ease of application and spreadability on the skin (42). The acceptable viscosity range for topical creams is between 50 and 1000 dPas. A linear model was selected to evaluate the viscosity response, supported by a significant p-value of 0.0001. The lack-of-fit test produced a p-value of 0.6646 (p > 0.05), indicating that the model was not significantly different from pure error, and thus accurately represented the observed data.
According to the model, stearic acid had a greater effect on increasing viscosity compared to triethanolamine. Increasing the stearic acid concentration led to higher viscosity, while increasing the triethanolamine concentration reduced viscosity. These findings are consistent with previous studies, which have shown that stearic acid can form complexes with other ingredients, contributing to increased viscosity (38). In contrast, triethanolamine is part of the aqueous phase, and since water has a lower viscosity than oil, its presence tends to reduce the overall viscosity of the emulsion.
Simplex Lattice Design Analysis
The simplex lattice design analysis considered the lack-of-fit results for each response variable. As previously described, the lack-of-fit values indicated that all response models were valid and could be used for further analysis in determining the optimal formulation. Using the desirability function approach, the optimization results identified the optimum formulation consisting of 17% stearic acid and 4% triethanolamine. These results were obtained from the desirability value generated by Design Expert software, where a desirability value approaching 1 indicates a highly optimized formula. This value reflects the predicted combination of the independent variables (stearic acid and triethanolamine) concerning the targeted responses: pH, spreadability, adhesiveness, and viscosity. The predicted response values for the optimal formulation are presented in Table 5.
Desirability serves as a function value that evaluates the software’s ability to meet the desired criteria for the final product. To validate the optimization, verification was performed by comparing the predicted and experimental (actual) values using statistical analysis. The verification results, shown in Table 6, indicate no significant difference between the predicted and observed values, as evidenced by p-values greater than 0.05. This confirms the reliability of the model in predicting the optimal cream formulation.
In Vitro Photoprotective Evaluation
In vitro photoprotective evaluation was carried out using the verification formula. The results of the photoprotective test are shown in Table 7. Photoprotective evaluation was conducted in vitro using spectrophotometry. Evaluation used parameters of SPF value, %Te and %Tp. The results of the photoprotective evaluation are shown in Table 7.
The SPF value obtained from the cream formulation indicates that it falls within the high sun protection category, defined as a sunscreen product with an SPF of 30 or above. The percentage of erythema transmission (%Te) and pigmentation transmission (%Tp) represent the proportion of ultraviolet radiation that penetrates the sunscreen and reaches the skin, potentially causing erythema and pigmentation, respectively (43). In this study, the %Te and %Tp values of the cream containing brown seaweed extract were found to meet the criteria for the sunblock category, characterized by %Te < 1% and %Tp ranging from 2% to 40% (44).
Brown seaweed is known to contain flavonoids (7), which contribute to photoprotection due to their ability to absorb ultraviolet (UV) radiation (45). Flavonoids possess aromatic chromophores (46), which are molecular structures capable of absorbing specific wavelengths of UVA and UVB radiation (47, 48). These chromophores play a critical role in mitigating UV-induced skin damage, thus supporting the potential of brown seaweed extract as a natural and effective sunscreen agent.
Conclusion
Optimization of the cream formula containing brown seaweed extract has been successfully achieved. Simplex lattice design analysis shows that there is an influence of stearic acid and triethanolamine on the responses (pH, viscosity, adhesiveness, and spreadability). The optimal formula was obtained with the proportion of stearic acid (17%) and triethanolamine (4%). The results of in vitro photoprotector evaluation showed that the cream has promising potential as a herbal sunscreen product.
Sunlight containing ultraviolet (UV) rays is harmful to human skin health. Sunscreen is one of the trendy and attractive cosmetics. Brown seaweed extract (Sargassum sp.) has the potential to be developed into a sunscreen product. This study aimed to optimize the formula of a cream containing brown seaweed extract and its in vitro photoprotection. A simplex lattice design approach was used to factor (triethanolamine and stearic acid) and responses (pH, viscosity, adhesiveness, and spreadability). The concentration of variation in stearic acid and triethanolamine affects the parameters of pH response, viscosity, adhesion, and spreadability. The simplex lattice design predicts the optimal formula with stearic acid (17%) and triethanolamine (4%). The verification proved that no significant difference between the predicted and actual results. The in vitro photoprotective evaluation results indicate that the brown seaweed extract cream is categorized as providing high sun protection and serving as a sunblock. Optimization of the brown seaweed extract cream formula using stearic acid and triethanolamine factors has been successfully achieved. The conclusion is that brown seaweed extract cream has the potential to be developed into a sunscreen cosmetic.
Lerche CM, Philipsen PA, Wulf HC. UVR: Sun, Lamps,
Pigmentation and Vitamin D. Photochemical and Photobiological Sciences.
2017;16(3):291–301.
Maverakis E, Miyamura Y, Bowen M, Correa G, Yoko Ono Y,
Goodarz H. Light, Including Ultraviolet. J Autoimmun. 2010;34(3):1–22.
Mansuri R, Diwan A, Kumar H, Dangwal K, Yadav D. Potential
of Natural Compounds as Sunscreen Agents. Pharmacognosy Reviews.
2021;15(29):47–56.
Santander Ballestín S, Luesma Bartolomé MJ. Toxicity of
Different Chemical Components in Sun Cream Filters and Their Impact on Human
Health: A Review. Applied Sciences. 2023;13:1–14.
Darmawan MA, Ramadhani NH, Hubeis NA, Ramadhan MYA, Sahlan
M, Abd-Aziz S, et al. Natural Sunscreen Formulation With A High Sun Protection
Factor (SPF) From Tengkawang Butter and Lignin. Industrial Crops and Products.
2022;177:1–8.
Resende DISP, Jesus A, Sousa Lobo JM, Sousa E, Cruz MT,
Cidade H, et al. Up-to-Date Overview of the Use of Natural Ingredients in
Sunscreens. Pharmaceuticals. 2022;15(3):1–29.
Sianipar EA, Gunardi SI. Anti-inflammatory and Antioxidant
Properties Of Sargassum Polycystum Ethyl Acetate Extract From Indonesia.
Journal of HerbMed Pharmacology. 2023;12(3):407–12.
Fatimah S, Alimon H, Daud N. Phytochemical Screening of
Sargassum sp and In Vitro Seed Germination test. Indonesian Journal of Science
and Technology. 2019;4(1):48–54.
Dharmawan D, Putriana NA. Total Phenolic Content and Sun
Protection Factor Value of Sargassum sp. Extract Seaweed. Jurnal Kelautan
Tropis. 2023;26(1):126–34.
Majeed M, Majeed S, Jain R, Mundkur L, Rajalakshmi HR, Lad
P, et al. A Randomized Study to Determine the Sun Protection Factor of Natural
Pterostilbene from Pterocarpus Marsupium. Cosmetics. 2020;7(1):1–13.
FDA. Sunscreen Drug Products For Over-Thecounter Human Use
[Stayed Indefinitely]. United States; 2004 p. 318.
Ihara K, Hirota M, Akitsu T, Urakawa K, Abe T, Sumi M, et
al. Effects of Emulsifying Components In The Continuous Phase of Cream On The
Stability of Fat Globules and The Physical Properties of Whipped Cream. Journal
of Dairy Science. 2015;98(5):2875–83.
Aldila S, Girsang V, Rahmawati IS, Mahari D, Sa’adah A.
Stability Testing Occured On Piroxicam Cream Preparation Using Stearic Acid and
Triethanolamine As Emulsifying Agents. Journal Science And Communnity Pharmacy.
2023;2(2):143–8.
Saryanti D, Prameswari SM. Optimization of Cream Ethanol
Extract of Duku Leaves (Lansium domesticum Corr.) as Antibacterial Against
Staphylococcus aureus Using the Simplex Lattice Design Method. Smart Medical
Journal. 2024;6(3):156–66.
Sopyan I, Gozali D, Insan Sunan KS, Guntina RK.
Design-Expert Software (DOE): An Application Tool For Optimization In
Pharmaceutical Preparations Formulation. International Journal of Applied
Pharmaceutics. 2022;14(4):64–70.
Putra IGNAWW, Septiari IGAA. Optimization of Gumitir Flower
Extract (Tagetes Erecta L.) Sunscreen Cream : Simplex Lattice Design Method.
Journal of Pharmaceutical Science and Application. 2023;5(2):93–100.
Wikantyasning ER, Astuti KF, Nurhakimah UF, Sula RD.
Optimization and In Vitro Evaluation of Creams Formulation Containing Spirulina
(Arthrospira platensis) Extract and Zinc Oxide Nanoparticles. International
Journal of Applied Pharmaceutics. 2021;13(1):34–7.
Alsawi S, Saleh W, Algadaafie D, Ali S, Kamal A. Formulation
and Evaluation of Cream of Green Tea Extract and Salicylic Acid for Acne
Treatment. AlQalam Journal of Medical and Applied Sciences. 2024;7(2):235–41.
Anggini AW, Fariha TA, Sari RK, Rafi M, Wientarsih I,
Sutardi LN. Hedonic Ratings and Physicochemical Stability of Antiaging Cream
Formulas with Natural Active Ingredients of Nanophytosome from Combination of
Merbau Wood-Gotu Kola Leaves Extracts and Essential Oils. BIO Web of
Conferences. 2023;77:1–9.
Amnuaikit T, Boonme P. Formulation and Characterization of
Sunscreen Creams With Synergistic Efficacy on SPF by Combination of UV Filters.
Journal of Applied Pharmaceutical Science. 2013;3(8):1–5.
Cherie Z, Ziegler GR, Fekadu Gemede H, Zewdu Woldegiorgis A.
Optimization and Modeling of Teff-Maize-Rice Based Formulation by Simplex
Lattice Mixture Design For The Preparation of Brighter And Acceptable Injera.
Cogent Food and Agriculture. 2018;4(1):1–19.
Apriani EF, Mardiyanto M, Hendrawan A. Optimization of Green
Synthesis of Silver Nanoparticles From Areca Catechu L. Seed Extract With
Variations of Silver Nitrate And Extract Concentrations Using Simplex Lattice
Design Method. Farmacia. 2022;70(5):917–24.
Valverde TM, Soares, Bruna Nayane Goncalves de Souza AM do
N, Andrade ÂL, Sousa LRD, Vieira PM de A, Santos VRBS, et al. Photoprotective
Investigation of Red Propolis Extract as Sunscreen Formulation in Polawax
Cream. International Journal of Molecular Sciences. 2023;24:1–18.
Mansur J de S, Breder MNR, Mansur MC d’Ascenção, Azulay RD.
Determinação Do Fator De Proteção Solar Por Espectrofotometria. An Bras
Dermatol Rio De Janeiro. 1986;61(3):121–4.
Nadia MA, Zulkarnain AK, Sulaiman TNS. Determination of
Photoprotective Capacity of Topical Gel Formulations Containing Bioactive
Compound Rutin and Evaluation of Physicochemical Stability. Tropical Journal of
Natural Product Research. 2023;7(9):3923–31.
Cumpelik BM. Analytical Procedures and Evaluation of
Sunscreens. J Soc Cosmet Chem. 1972;23(6):333–45.
Hakim MM, Patel IC. A Review on Phytoconstituents of Marine
Brown algae. Future Journal of Pharmaceutical Sciences. 2020;6(1):1–11.
Andriyani R, Kosasih W, Ningrum DR, Pudjiraharti S. Effect
of Temperature, Time, and Milling Process On Yield, Flavonoid, and Total
Phenolic Content of Zingiber Officinale Water Extract. IOP Conf Series: Earth
and Environmental Science. 2017;60:1–5.
Anggriyani IS, Endriyatno NC. Formulation and Physical
Testing of Tamarind (Tamarindus indica L.) Leaf Ethanol Extract Cream With A
Combination of Triethanolamine and Stearic Acid. Indonesia Natural Research
Pharmaceutical Journal. 2024;9(1):25–38.
Okafo SE, Anie CO, Alalor CA, Nwankwo LU. Evaluation Of
Physicochemical and Antimicrobial Properties of Creams Formulated Using
Pterocarpus Santalinoides Seeds Methanol Extract. Journal of Applied
Pharmaceutical Science. 2023;13(05):126–35.
Tania BL, Dwiastuti R, Budi A, Lestari S, Setyaningsih D.
Sunscreen Cream Formulation of Noni Leaf Extract (Morinda citrifolia L .) with
Emulsifier Combination of Tween 80 and Lecithin. Pharmacy and Pharmaceutical
Science Journal. 2022;9(3):262–71.
Fiume MM, Heldreth B, Bergfeld WF, Belsito D V., Hill RA,
Klaassen CD, et al. Safety Assessment of Triethanolamine and
Triethanolamine-Containing Ingredients as Used in Cosmetics. International
Journal of Toxicology. 2013;32(Supplement 1):59S-83S.
Azim H, Kalavathy R, Julianto T, Sieo CC, Ho YW. Effect of
Heat, pH and Coating Process with Stearic Acid Using A Fluidized Bed Granulator
on Viability of Probiotic Lactobacillus reuteri C 10. African Journal of
Biotechnology. 2012;11(26):6857–65.
Popoola CA, Ayo JA, Adedeji OE, Akinleye O. Triethanolamine
(TEA) As Flow Improver For Heavy Crude Oils. IOSR Journal of Applied Chemistry
Ver I. 2015;8(3):34–8.
Alberts B, Johnson A, Lewis J, Raff M, Roberts K, P. W.
Molecular Biology of the Cell. 4th ed. New York: Garland Science; 2002.
Aisyah Y, Irfan, Yunita D, Ikhwana Y. Formulation and
Characteristics of Skin Cream With The Addition of Essential Oil Blend. IOP
Conference Series: Earth and Environmental Science. 2024;1297:1–9.
Yakub J, Setyani W. Optimization of Stearic Acid and
Triethanolamine in The Antibacterial Cream Staphylococcus aureus Ethanol
Extract of Papaya Seeds (Carica papaya L.): Factorial Design Method. Journal of
Pharmaceutical Sciences and Community. 2023;20(1):1–9.
Królikowska K, Pietrzyk S, Pustkowiak H, Wolak K. The Effect
Of Cassava And Wheat Starches Complexation With Selected Fatty Acids On Their
Functional Properties. Journal of Food Science and Technology.
2022;59(4):1440–9.
Rohmani S, Miararani N, Yugatama A, Ermawati DE, Prihapsara
F. Formulation and The Release of Eugenol From Cream Using Glycerin Base. IOP
Conference Series: Materials Science and Engineering. 2019;578:1–6.
Widati AA, Fahmi MZ, Sakti SCW, Rizqiyanika L, Cahyandaru N,
Rahmawati Z, et al. SiO2-Fatty Acids and TiO2-Fatty Acids With The Role Of
Based Hydrophobic Coatings For The Preservation of Andesite Stone.
International Journal of Conservation Science. 2024;15(3):1303–14.
Mohapatra R, Senapati S, Sahoo C, Mallick S. Thermodynamic
Properties of Ocular Permeation of Diclofenac: Effect of Triethanolamine.
Farmacia. 2016;64(1):72–81.
Rohmani S, Dinda KE, Ainurofiq A. Formulation and Evaluation
of The Cream Made From Potassium Azeloyl Diglycinate As An Anti-Aging. Journal
of Physics: Conference Series. 2021;1912:1–12.
Wardatun S, Mahyuni S, Setiawan P, Sciences N, Pakuan U. The
Sunscreen Activities of Ethanol, Ethyl Acetate, N-Hexane, And Water Fractions
From Papaya (Carica Papaya L.) Leaf Extract. Indonesian Journal of
Pharmaceutics. 2023;5(2):422–31.
Kusmita L, Nur Prasetyo Edi A, Dwi Franyoto Y, Mutmainah,
Haryanti S, Dwi Retno Nurcahyanti A. Sun Protection and Antibacterial
Activities of Carotenoids From The Soft Coral Sinularia Sp. Symbiotic Bacteria
From Panjang Island, North Java Sea. Saudi Pharmaceutical Journal.
2023;31(8):1–10.
Ghazi S. Do The Polyphenolic Compounds From Natural Products
Can Protect The Skin From Ultraviolet Rays? Results in Chemistry.
2022;4(May):100428.
Sisa M, Bonnet SL, Ferreira D, Van Der Westhuizen JH.
Photochemistry of Flavonoids. Molecules. 2010;15(8):5196–245.
Millington KR. Improving The Whiteness and Photostability of
Wool. In: Johnson NAG, Russell IM, editors. Advances in Wool Technology.
Woodhead Publishing; 2009. p. 217–47.
Fonseca M, Rehman M, Soares R, Fonte P. The Impact of
Flavonoid-Loaded Nanoparticles in the UV Protection and Safety Profile of
Topical Sunscreens. Biomolecules. 2023;13(3):1–32.
Equation 2 | Product of transmission (T) and erythemal effectiveness (Fe) at each wavelength, then dividing by the total erythemal effectiveness (ΣFe), where Ee is the effective erythema energy transmitted.
Equation 3 | Product of transmission (T) and pigmentation effectiveness (Fp) at each wavelength, then dividing by the total pigmentation effectiveness (ΣFp), where Ee is the effective pigmentation energy transmitted.
