New Insights into Common Bean (Phaseolus vulgaris L.) Sprouts: Pilot Studies on the Formulation of a Cosmeceutical Based on Micellar Extracts Bean Sprouts

Featured Application

The conducted research has demonstrated the effectiveness of the innovative micellar extract from common bean sprouts (Phaseolus vulgaris L.), which represents a novelty both in its modern micellar form and in its application as an ingredient in cosmetics. In previous in vitro studies, the micellar extract exhibited significantly better activity in inhibiting collagenase, elastase, tyrosinase, cyclooxygenase, and neutralizing free radicals compared to the standard dry extract. A cosmetic cream formulated with the addition of this micellar extract outperformed a reference antiwrinkle cream containing synthetic ingredients with proven antiaging and moisturizing effects. The results of our research indicate the high application potential of the proposed natural plant ingredient in an innovative form, opening up new possibilities for cosmeceutical formulations in the cosmetics industry. The use of the micellar extract enables the elimination of synthetic substances, which may cause skin irritation, in favor of effective and safe natural alternatives.

Abstract

The search for new active plant ingredients is crucial for the development of innovative cosmetic products. Micellar extracts from plant raw materials are not yet widely popular in cosmetics; however, scientific reports suggest that this form of extract is superior to standard extracts due to its enhanced ability to solubilize active compounds, improve their stability, and facilitate better penetration into the skin. For this reason, our research focuses on an innovative in its applicative form micellar extract from common bean sprouts (Phaseolus vulgaris L.) with a favorable composition and promising biological activity. The aim of this study was to develop a cream formulation containing this extract and evaluate its effects using in vivo tests. Six formulations were assessed for their physicochemical properties, and a comparative analysis was conducted against a reference cream and placebo cream. For the in vivo efficacy tests, the cream, which exhibited optimal physicochemical properties and long-term stability, was selected and tested on a group of 45 volunteers. The evaluation utilized Multi-Probe Adapter Systems to compare the cream with the micellar extract, a placebo cream (cream without the extract), and a reference antiaging cream. Results demonstrated that the formulation with micellar extract exhibited superior moisturizing, antiaging, and skin-brightening properties compared to the control groups. After 12 weeks of application, the micellar extract cream improved skin hydration by 22.31%, while the placebo cream showed only a 3.52% increase, and the reference cream achieved a 13.96% improvement. The antiaging effect, assessed based on improvements in skin elasticity parameters (R2 and R5), showed increases of 13.30% and 12.33% for the micellar extract cream, compared to 8.5% and 2.32% for the placebo cream and 6.38% and 3.82% for the reference cream, respectively. In conclusion, the common bean sprouts micellar extract shows potential as an effective active ingredient for skin care products, highlighting its promising applications in the cosmetics industry.

1. Introduction

Modern cosmetology aims to create formulations that not only improve skin appearance but also enhance its biological functions. Evaluating the efficacy of new cosmetic creams involves both subjective assessments with volunteers and objective instrumental measurements. The cosmetics industry is continually exploring new plant, mineral, and animal extracts to combat skin aging. Recent research has focused on extracts from various parts of the common bean (Phaseolus vulgaris L.), including roots, leaves, stems, and seeds. In traditional medicine, the common bean has been used as a skin softener, cleanser, and treatment for eczema and itching [1].

Seed extracts from the common bean are promising cosmetic ingredients due to their high content of bioactive compounds, including peptides, polyphenols, flavonoids, vita-mins (e.g., C and E), and minerals (e.g., zinc and magnesium). Previous studies by Santos, E. et al. [2] suggest that these extracts offer moisturizing, antiaging, anti-inflammatory, and antioxidant benefits. Extracts from other bean varieties also exhibit beneficial effects. For example, black turtle bean (P. vulgaris) and mung bean (Vigna radiata (L.) R.Wilczek) seed extracts are used in cosmeceuticals for their antioxidant potential and enzyme-inhibiting properties [3,4]. Similarly, azuki bean (Vigna angularis (Willd.) Ohwi & H.Ohashi) and common bean seed powders have demonstrated whitening, sebum-regulating, and erythema-reducing effects in cosmetic formulations [5,6].

Sprouted seed extracts, known for their high nutritional value, are increasingly utilized in cosmetics [7]. Examples include lotus sprout extract (Nelumbo nucifera Gaertn.) [8], peanut (Arachis hypogaea L.) [9], white mustard (Sinapis alba L.), and sunflower (Helianthus annuus L.) sprouts [10]. Common bean sprouts are valued in traditional medicine and dietetics for their rich nutritional and health-promoting properties [2]. A review of the literature revealed a lack of information regarding the use of common bean sprout extracts for cosmetic purposes. Therefore, we undertook an attempt to obtain an extract using an innovative micelle-assisted extraction method and subsequently analyzed its properties in comparison to an extract obtained through traditional extraction methods.

Our research demonstrated that the micellar extract from common bean sprouts (P. vulgaris) is a groundbreaking solution in cosmetology. This extract contains polyphenols such as caffeic, ferulic, and coumaric acids, as well as flavonoids like rutin and quercetin [11]. These compounds provide an extract with anti-inflammatory, antioxidant, antiaging (anti-collagenase and anti-elastase), and whitening (anti-tyrosinase) properties, as well as the ability to stimulate collagen synthesis [11].

In our previous studies, we compared the properties of micellar extract from common bean sprouts with a dry extract obtained using traditional methods. The results clearly showed that the micellar extract exhibited significantly superior biological properties. Although the dry extract also demonstrated the aforementioned properties, its effectiveness was considerably lower. These findings highlight the innovative nature of the micellar extract and its potential for use in modern cosmetic products.

The aim of this study was to develop a novel cream formulation containing micellar extract from common bean sprouts (P. vulgaris), evaluate its physicochemical properties, test its stability, and verify its efficacy in in vivo studies. This study also aimed to compare the effectiveness of the developed cream with a reference cream containing synthetic active ingredients, focusing on its antiwrinkle, moisturizing, and firming effects.

2. Materials and Methods

2.1. Chemical and Reagents

TegoCare CG 90 (Cetearyl Glucoside), TegoCare 2S2 (Steareth-2)—free gift (Evonik; Warszawa, Poland), Sucrose Stearate, Behenyl Alcohol, Sensolene (Ethylhexyl Olivate), Myristyl Myristate, Sodium Phytate (Lotioncrafter; Eastsound, WA, USA), Purephos Alpha (Cetyl Palmitate), Glyceryl Monostearate (GMS) (IMCD; Warszawa, Poland), Glyceryl Stearate Citrate (GSC), Squalane Light (C12-15 Alkane), Sodium Benzoate, Propanediol, Shea Light (Shea Butter Ethyl Esters), Shea Butter, Sweet Almond Oil, L-Alpha Tocopherol, Hyaluronic Acid, Argania Spinosa Oil (e-naturalne.pl; Warszawa, Poland), Emulgade Succro (Sucrose Polystearate), Caprylic/Capric Triglyceride (C/CT), Cosmedia SP (Sodium Polyacrylate) (BASF; Warszawa, Poland), Cetyl Alcohol, Cetearyl Alcohol, Isopropyl Myristate, Isopropyl Palmitate, Stearic Acid (Sigma; Rzeszów, Poland), Sepiplus S (Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Poly-isobutene, and PEG-7 Trimethylolpropane Coconut Ether), Simulgel 600 (Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Isohexadecane, and Polysorbate 80) (Seppic; Warszawa, Poland), 75% Panthenol, Methyl Glucose Sesquistearate (MSG), PrevAcion PCG (Phenoxyethanol and Caprylyl Glycol), Lipowax NF (Cetearyl Alcohol and Polysorbate 60) (Green Club; Gdańsk, Poland), LexFeel™ Natural (Heptyl Undecylenate) (Bay House; Great Britain, UK), and L-Arginine (Carl Roth; Karlsruhe, Germany) were used.

2.2. Development of Recipes for Creams with Common Bean (Phaseolus vulgaris L.) Sprout Extract and Selection of the Cream with the Most Favorable Physicochemical Properties

2.2.1. Preparation of the Extract

A detailed description of the preparation of the dry extract from common bean sprouts and the study of its in vitro effectiveness has been provided in previous research [11]. Bean sprouts were cultivated in a two-tier Tribest TRIFL2000 sprouter equipped with an automatic watering system, adjusted based on the season (spring/summer: every 30 min; autumn/winter: every 60 min). Prior to sprouting, seeds were soaked in water for 24 h. After soaking, they were placed on two levels of the sprouting chamber and the watering schedule was set to summer mode (every 30 min). The room temperature was maintained at 22 °C. Sprouts were grown for 5–7 days until the first leaf buds emerged. Once harvested, they were cut at the seed level and were crushed into pieces of about 5 mm. Measured portions of the material were placed in glass bottles with caps. A 70% ethanol solution with 0.4% (w/w) Brij L35 (Polyoxyethylene (23) lauryl ether) was used as the extractant. The raw material was combined with the solvent and the bottles were shaken at 300 rpm for 2 h. Next, the mixture was sonicated at 40 ± 2 °C for 20 min.

Afterward, the extractant was decanted and filtered through Whatman filter paper. The process was repeated with fresh solvent under the same conditions. The collected extracts were concentrated under reduced pressure using an IKA RV8 Flex evaporator, a thermostated water bath (IKA HB10), and an IKA Vacstar control pump. The concentrated extract was frozen and lyophilized in a vacuum concentrator (Labconco, Kansas City, MO, USA) to produce a dried residue.

A dry extract weighing 0.4 g was dissolved in 9.6 g of water and supplemented with propanediol to a total weight of 100 g. This extract was subsequently added to the creams.

2.2.2. Preparation of Cosmetic Creams

The recipes for cosmetic creams with common bean (P. vulgaris) sprout extract were developed based on an in-house concept. Six cosmetic creams were prepared, each in quantities of 500 g. The formulations differed in the type and amount of emulsifiers, co-emulsifiers, emollients, oils, and thickening agents. The compositions of the individual creams are presented in

Table 1. Composition of cosmetic creams named C1–C6 and reference cream named CR.

C1		C2		C3
Phase A—oil
GSC	3.0	MSG	3.0	Cetyl palmitate	2.5
Emulgade succro	1.5	MG	1.25	Cetyl alcohol	2.0
Sucrose stearate	0.7	Sucrose stearate	0.25	Behenyl alcohol	1.0
Cetyl alkohol	1.5	Cetyl alkohol	1.5	Heptyl undecylate	0.75
Heptyl undecylate	0.7	Heptyl undecylate	1.0	Isopropyl Mirystate	0.75
Isopropyl Mirystate	0.7	Isopropyl Mirystate	0.5	C/CT	2.0
C/CT	3.5	C/CT	3.5	C12-15 alkane	0.7
C12-15 alkane	0.7	C12-15 alkane	0.75	Ethylhexyl Olivate	1.0
Ethylhexyl Olivate	1.5	Shea light	0.75	Shea butter	2.0
Shea butter	1.5	Shea butter	1.5	Sweet almond oil	3.0
Sweet almond oil	3.0	Sweet almond oil	3.0	Argania spinosa oil	0.5
Argania spinosa oil	0.5	Argania spinosa oil	0.5	Shea light	1.0
Dicapryl propanediol	0.4	Dicapryl propanediol	0.5
Phase B—water
Propanediol	2.2	Propanediol	2.2	Propanediol	2.0
Sodium phytate	0.1	Sodium phytate	0.1	L-arginine	1.5
Panthenol	1.0	Panthenol	1.0	Sodium phytate	0.1
Seppiplus S	1.5	Seppiplus S	1.5	Panthenol	1.0
Aqua	do 100.0	Aqua	do 100.0	Seppiplus S	1.20
				Aqua	do 100.0
Phase C—additives
Phaseolus vulgaris L. sprotus micellar extract			4.0
α-tocopherol			1.0
Phenoxyethanol, Caprylyl Glycol			1.0
C4		C5		C6
Phase A—oil
GSC	3.63	Lipowax NF	2.0	GSC	6.0
MG	1.73	Emulgade sucro	1.5	Cetearyl alcohol	2.5
Sucrose stearate	0.75	MG	1.5	Behenyl alcohol	0.5
Cetyl alcohol	1.5	Sucrose stearate	0.5	Heptyl undecylate	3.0
Behenyl alcohol	0.5	Cetyl alcohol	1.5	Isopropyl palmitate	2.0
Heptyl undecylate	3.0	Behenyl alcohol	0.5	C/CT	2.0
Isopropyl mirystate	2.0	Heptyl undecylate	0.5	C12-15 alkane	1.0
C/CT	2.0	Isopropyl Mirystate	1.0	Shea butter	3.0
C12-15 alkane	0.7	C/CT	2.5	Dulcis amygdalarus oil	4.0
Shea butter	1.5	Shea butter	1.5	Argania spinosa oil	0.5
Sweet almond oil	3.0	Sweet almond oil	3.0
Argania spinosa oil	0.5	Argania spinosa oil	0.5
Phase B—water
Propanediol	2.2	Propanediol	2.0	Propanediol	2.2
Sodium phytate	0.1	Sodium phytate	0.1	Sodium phytate	0.1
Panthenol	1.0	Panthenol	1.0	Panthenol	1.0
Simulgel 600	1.5	Simulgel 600	1.0	Cosmedia SP	1.5
Aqua	do 100.0	Aqua	do 100.0	Aqua	do 100.0
Faza C
Phaseolus vulgaris L. sprotus micellar extract			4.0
α-tocopherol			1.0
Phenoxyethanol, Caprylyl Glycol			1.0
Reference cream (CR)
Aqua, Glycerin, Octocrylene, Cetearyl Alcohol, Methylpropanediol, Caprylic/Capric Triglyceride, Ethylhexyl Salicylate, Glyceryl Stearate Citrate, Isopropyl Palmitate, Butyl Methoxydibenzoylmethane, Octyldodecanol, Dimethicone, Synthetic Beeswax, Argania Spinosa Kernel Oil, Ubiquinone, Creatine, 1-Methylhydantoin-2-Imide, Vitis Vinifera Seed Oil, Calcium Pantothenate, Tocopherol, Ethylhexylglycerin, Xanthan Gum, Carbomer, Trisodium EDTA, Sodium Hydroxide, Phenoxyethanol, Benzyl Alcohol, Limonene, Parfum

.

The creams were prepared using the hot method. The emulsifier and oil phase ingredients, as well as the aqueous phase ingredients, were heated separately in beakers to 80 °C. The oil phase was then added to the aqueous phase with continuous stirring using an IKA high-speed mixer (IKA^® MICROSTAR 7.5 Control, Königswinter, Germany) at a speed of 800 rpm. After cooling the formulation to approximately 40 °C, the active ingredients—micellar bean sprout extract (Phaseolus vulgaris), vitamin E, and preservative—were added. The mixture was stirred for an additional 5 min at 600 rpm.

To homogenize the droplet size of the oil phase and achieve a uniform structure, the creams were further homogenized using a high-speed homogenizer (IKA^® T25 Homogenizer, Germany) at 15,000 rpm for 15 min. The final creams were transferred to packaging and stored at room temperature.

2.3. Evaluation of Physicochemical and Organoleptic Properties

The evaluation of physicochemical properties was conducted based on the guidelines provided in the literature [12,13,14,15,16,17,18,19,20,21,22,23].

2.3.1. Evaluation of Centrifugal Stability

To preliminarily assess the stability of the obtained formulations, a centrifugal test was performed [12]. Samples of each formulation were placed in Eppendorf^® test tubes and subjected to centrifugation using an Eppendorf Centrifuge 5418 R (Hamburg, Germany) at 3000 rpm for 15 min. Subsequently, the samples were visually inspected for any signs of phase separation. The test was repeated three times for each sample.

2.3.2. Organoleptic Evaluation of the Preparations

The products were evaluated for their odor, color, texture, and spreadability on the back of the hand in a self-conducted, subjective assessment. The odor was categorized as unpleasant (chemical), odorless, or pleasant. The texture was evaluated as either a smooth cream without lumps (homogeneous) or a cream with visible lumps (nonhomogeneous), with solid components such as fatty alcohols being noticeable during application. Spreadability was assessed by applying the cream to the skin of the wrist and massaging it in—good spreadability indicated that the cream was absorbed into the skin without leaving a greasy residue, whereas poor spreadability was characterized by prolonged absorption time, streaking on the skin, and whitening.

2.3.3. In Vitro Occlusion Assessment

The ability of the obtained creams and the reference cream to inhibit transepidermal water loss (TEWL) was evaluated using an occlusion test, following the method described by Wissing [13]. Beakers (100 mL) were filled with exactly 50 g of water and tightly covered with filter paper. For each sample, 200 mg of cream was applied evenly across the entire surface of the filter paper. A sample without cream served as a control. The samples were stored at 32 °C and 50–55% relative humidity for 24 h. After this period, the filter paper was removed and the samples were weighed. Each experiment was conducted in triplicate.

The occlusion factor F (%) was calculated using Equation (1):

$$\mathit{F}={\displaystyle \frac{\left(\mathit{A}-\mathit{B}\right)\mathit{\ast }100\%}{\mathit{A}}}$$

(1)

where A is the water loss in the control (g) and B is the water loss in the sample (g).

2.3.4. Determination of Emulsion Type

The emulsion type was determined by adding dyes that selectively stain one phase of the cosmetic sample, followed by microscopic analysis (Optical Microscope–Leica ICC 50HD with LAS V4.5 software (Germany)). A small amount of cream was applied to a slide, and methyl blue and Sudan III dyes were added. The mixture was stirred with a dipstick until thoroughly combined, covered with a coverslip, and analyzed under a microscope at 40× magnification. The test was repeated once for each sample.

2.3.5. Determination of Oil-Phase Droplet Size

A small amount of the preparation was applied to a slide, covered with a coverslip, and analyzed using an optical microscope at 40× magnification. Using the LAS V4.5 software, a photograph of the sample was taken and the diameters of 300 randomly selected oil-phase droplets were measured. The test was conducted on 3 separate samples. In each sample, 100 randomly selected droplets were evaluated in different fields of view. The arithmetic mean and standard deviation were calculated using Microsoft Excel 2021.

2.3.6. Determination of pH

The pH value of the creams was measured using a pH meter (Elmetron CP-411, Zabrze, Poland) at 20 °C. The measuring electrode was directly immersed in the preparation. The test was repeated three times.

2.3.7. Rheological Analysis of the Creams

The prepared formulations were subjected to rheological evaluation using a Rheolab QC rotational rheometer (Anton Paar, Graz, Austria) with a CC27/S cylinder and a C-PTD 180/AIR/QC Peltier thermostat (Anton Paar, Austria). The RheoCompass™ software 1.30.1164 (Anton Paar, Austria) was used to analyze the data. The creams were placed in the outer cylinder, filling it to a mark on the inner wall. After installing the inner cylinder, the cream was left for 30 min to regain its structure at 22 °C and, next, the test was conducted. Initial agitation was performed at 5 s⁻¹ for 4 min. Flow curves were determined based on the shear rate (0.1 s⁻¹ to 100 s⁻¹). The data were approximated using the Ostwald de Waele and Herschel–Bulkley rheological models. Thixotropic properties were determined by measuring viscosity during increasing and decreasing shear rates.

2.3.8. Spreadability Test for Creams

Spreadability was measured to determine the surface area covered by the formulation under increasing loads. The test was conducted at 22 °C using an extensometer. Precisely 1 g of cream was placed on a graduated disc and covered with the top plate. A load of 200 g was applied every minute, up to a total of 1000 g. After each minute, the radii in four perpendicular directions were measured. The area (P) in cm² was calculated using Equation (2). The test was repeated three times.

$$\mathit{P}=\mathit{\pi }{\mathit{r}}^2$$

(2)

The spreading factor Sf in (cm²/g) was then calculated according to Equation (3):

$$\mathit{S}\mathit{f}={\displaystyle \frac{\mathit{P}}{\mathit{m}}}$$

(3)

where P is the area of the stretched cream in cm² and m is the load (g).

2.3.9. Slip Test for Creams

The slip test complements the spreadability tests [14]. The slip evaluation of the formulations was conducted using the texturometer (SHIMADZU EZ-SX, Tokyo, Japan) apparatus and TRAPEZIUMX software 1.5.0. A 0.5 g sample of the formulation was applied to the sliding table. A slip plate was placed on the cream sample and a string was attached to the plate. The string was gradually tightened until the plate started to move. The test was repeated three times. The averaged results are presented as force values expressed in millinewtons (mN).

2.3.10. Long-Term Stability and Accelerated Aging Studies for C1 Cream

Physical stability tests were carried out under accelerated (180 days; 40 ± 2 °C/75 ± 5% relative humidity) and long-term (180 days; 20 ± 2 °C; 4 ± 2 °C) conditions. For this purpose, 900 g of cream was prepared according to the C1 recipe and divided into 3 containers of 300 g. The sample containers were stored at the indicated temperatures. At predetermined intervals, i.e., after 7, 30, 90, and 180 days, each sample was subjected to tests, including organoleptic evaluation, centrifugal stability, viscosity, pH, and microscopic analysis with oil-phase size determination. These tests allowed the stability of the formulation to be assessed over time. Tests were performed after 1 day, 7 days, 30 days, 90 days, and 180 days of storage under the conditions described above. The same tests were also performed for the reference cream.

2.4. Evaluation of the Efficacy of Common Bean (Phaseolus vulgaris L.) Sprout Extract Cream Under In Vivo Conditions

The research project entitled ‘Plant micellar extracts of common bean sprout as active ingredients of creams for mature skin care’ was positively reviewed and approved by the Bioethics Committee of the Medical University of Lublin with the number KE 0254/191/2021 of 19 August 2021.

The study involved women with mature skin aged 40 years or older. The study included 45 female subjects aged 42–64 years (mean age 51.91 ± 6.13 years). There were no statistically significant differences in age between the study groups (ANOVA F = 0.17, p = 0.84). Individuals with atopic skin, a tendency for allergies, or active inflammatory lesions were excluded from the study. Individuals who were currently suffering from or had a history of cancer, as well as those undergoing cancer treatment (radiotherapy and chemotherapy), were also excluded from the study. Each subject provided voluntary, informed, written consent to participate in the research procedure. The participants were informed that they could withdraw from the study at any time without giving a reason. The study was conducted as a single-blind trial. The participants were randomly assigned to three groups, each comprising 15 individuals. They were instructed to apply the assigned cream twice a day for a period of 12 weeks, with no other skincare creams allowed during the experiment, except for makeup and facial makeup remover.

Group one—placebo group: participants in group one received cream C1 for testing but without the micellar extract of common bean sprout (P. vulgaris) (placebo). Group two—extract group: participants in group two received cream C1 for testing, containing 4% micellar extract of common bean sprout (P. vulgaris) (extract). Gropu three—reference group: participants in group three received a commercially popular antiwrinkle cream for testing (CR).

The reference cream, according to the manufacturer’s data, is designed for the care of mature, dry, and demanding skin. The cream contains active ingredients such as synthetic coenzyme Q10, which stimulates cellular metabolism, increases collagen production, and acts as an antioxidant, as well as creatine, also of synthetic origin, which supports collagen and elastin production, provides energy to skin cells, and aids in skin regeneration. Additionally, the formula includes 1-Methylhydantoin-2-Imide, a synthetic compound with moisturizing properties.

On the day of the test, participants were instructed not to apply the cream or makeup. All measurements were taken in the same room under controlled conditions of temperature (22–24 °C) and humidity (40–50%), at similar times of day, following a minimum of 15 min of acclimatization in the measurement room.

To evaluate the effectiveness of the creams, skin parameters were measured before the experiment (measurement 1—M1), after 4 weeks (measurement 2—M2), after 8 weeks (measurement 3—M3), and after 12 weeks (measurement 4—M4).

Selected skin parameters were measured using the MPA—Multi-Probe Adapter Systems (Courage + Khazaka electronic GmbH, Köln, Germany). Skin hydration, sebum level, skin elasticity, and melanin and redness levels were assessed with the following probes: Corneometer^® CM825, Sebumeter^® SM 815 cassette, and Cutometer^®, Mexameter^® MX 18.

Each measurement was taken at 3 predetermined locations on the facial skin: on the left cheek, right cheek, and forehead (approximately 2 cm above the eyebrow line). The sebum test was conducted only on the forehead at 3 predetermined points. The result was provided as the average of these measurements. All participants completed the study and none developed adverse reactions such as skin rash or redness.

Statistical Methodology

All statistical calculations were carried out using STATISTICA 13.5 (StatSoft) statistical software and an Excel spreadsheet. Statistical analyses were conducted to evaluate the effect of regular use of the cream with micellar extract of common bean sprouts (Phaseolus vulgaris). It was hypothesized that the tested preparation would significantly improve selected skin parameters, such as hydration, elasticity, melanine index (MI), erythema index (EI), and sebum secretion, compared to the control group and reference cream.

The Shapiro–Wilk test was used to assess whether the quantitative variable came from a population with a normal distribution, and equality of variance was tested using Levene’s test. The significance of differences between more than two independent groups was evaluated using analysis of variance (ANOVA) or the Kruskal–Wallis test (if the distribution was not normal). If statistically significant differences were found, post hoc tests were performed; for the F-test (ANOVA), the Tukey test was used and, for the Kruskal–Wallis test, the Mann–Whitney U test was applied. The significance of differences between more than two groups in the model of related variables was assessed using ANOVA with repeated measures, followed by Tukey’s HSD or Friedman’s test, and Kendall’s concordance coefficient if the data did not follow a normal distribution. Correlations between two dependent groups were compared using the Wilcoxon rank-sum test. In all calculations, a p-value of 0.05 was considered the threshold for statistical significance.

3. Results

3.1. Evaluation of Physicochemical and Organoleptic Properties

The tested formulations and the reference cream underwent comprehensive analyses, including short-term stability tests, physicochemical evaluations, rheological assessments (viscosity, thixotropy, flow behavior index, and consistence coefficient), and occlusivity measurements. The results enabled the identification of a formulation with properties comparable to the reference cream (CR). This strategy minimized the risk of subjective bias arising from potential differences in sensory appeal among the tested products. All tested creams had a uniform consistency, a pleasant fragrance, and a beige or yellowish color. When applied to the hands, they spread easily and were quickly absorbed. The formulations, together with the reference cream, were stable o/w emulsions, showing no signs of phase separation in the centrifugation test.

Detailed findings, including stability and physicochemical properties, are summarized in

Table 2. Summary of the physical and chemical analysis results for the cosmetic creams obtained and the reference cream.

	C1	C2	C3	C4	C5	C6	CR
F	55.1 ± 1.4	51.1 ± 0.5	49.1 ± 4.7	58.8 ± 1.5	52.5 ± 4.8	41.7 ± 2.3	49.36 ± 4.3
Φ	3.63 ± 1.56	3.31 ± 0.71	2.98 ± 0.52	3.01 ± 0.62	3.04 ± 0.95	3.42 ± 0.89	4.4 ± 1.14
η5s−1	18.09	27.01	7.13	30.75	27.7	34.38	17.73
η50s−1	2.41	3.56	1.36	4.19	3.41	4.55	2.58
A × 103	692	1366.3	463.51	2490	1833	1532.6	1099
K	73.39	113	25.15	127.48	115.7	144.48	67.22
p	0.13	0.12	0.25	0.12	0.1	0.11	0.1
Ʈr0	49.2	133.67	---	90.17	----	125.63	84.54
k	25.98	6.35	-----	55.75	----	30.6	3.5
n [-]	0.25	0.5	----	0.19	----	0.31	0.65
Sf	2.95 ± 0.05	2.59 ± 0.04	3.59 ± 0.02	2.88 ± 0.03	2.85 ± 0.02	2.56 ± 0.03	3.11 ± 0.04
S	76 ± 3	105 ± 1	44 ± 3	80 ± 0.5	79 ± 0.2	108 ± 1	64 ± 4
pH	5.65 ± 0.01	6.02 ± 0.02	7.06 ± 0.04	5.55 ± 0.02	6.76 ± 0.02	5.15 ± 0.01	6.54 ± 0.03

F (%)—occlusive factor, Φ (µm)—average droplet size of the oil phase (µm), η₅s⁻¹ (Pa·s)—viscosity measured at a shear rate of 5 s⁻¹, η₅₀s⁻¹ (Pa·s) viscosity measured at shear rate of 50 s⁻¹, A (Pa/s)—thixotropy area, K (Pa·s)—consistency coefficient according to the Ostwald de Waele model, p (-)—flow behavior index, Ʈr₀ (Pa)—yield stress according to the Herschel–Bulkley model, k (Pa·s)—consistency factor according to the Herschel–Bulkley model, n (-)—flow behavior index, Sf (mm²/g)—spreadability index at 1000 g load, pH (-)—pH value, S (mN)—slip, F (%)—occlusion factor.

.

The ability of a cosmetic cream to occlude, i.e., stop transepidermal water loss (TEWL), allows for the prediction of how well it will moisturize the skin. The C1–C6 creams and the reference cream showed a comparable occlusion factor (F) of around 50%.

Microscopic analysis of the mean droplet size of the oil phase (Φ) showed that all formulations had similar droplet sizes, ranging from 2.98 ± 0.52 µm for cream C3 to 3.42 ± 0.98 µm for cream C6. The droplet size for the reference cream was 4.4 ± 1.14 µm.

Rheological studies conducted using a rotational viscometer demonstrated that the creams exhibited similar rheological properties. All samples displayed pseudoplastic flow behavior, which could be modeled using the Ostwald de Waele model. Among the tested creams, C3 and C6 had extreme values.

Cream C3 showed the lowest absolute viscosity measured at a shear rate of Dr = 5 s⁻¹, amounting to 7.13 Pa·s, a consistency coefficient (K) of 25.15 Pa·s, and a low thixotropy of 463.51 Pa/s. In contrast, cream C6 demonstrated the highest absolute viscosity under the same conditions, reaching 34.38 Pa·s, a consistency coefficient (K) of 144.48 Pa·s, and a thixotropy of 1532.6 Pa/s.

This resulted in a lower spreadability coefficient for cream C6 (Sf = 2.56 mm²/g) and a higher force required to spread the cream (108 ± 1 mN). On the other hand, cream C3 had the highest spreadability coefficient (Sf = 3.59 mm²/g) and the lowest force required to spread the cream (44 ± 3 mN).

3.2. Long-Term Stability Analysis of the Selected Formulation for Volunteer Testing

The obtained test results allowed for a preliminary comparative analysis of the prepared cosmetic creams containing common bean sprout extract (P. vulgaris) with a reference cream. Due to the comparable physicochemical parameters for the C1–C5 creams (Table 2), each of them could potentially be selected as the final product for testing on volunteers. Given the similar rheological properties to the reference cream (CR) and the comparable occlusive effect, cream C1 was chosen for further testing, including long-term stability and accelerated aging tests. After long-term stability analysis and accelerated aging tests, the cream was chosen for in vivo efficacy tests with the volunteers. The results obtained for long-term stability tests for C1 cream and reference cream are summarized in

Table 3. Summary presentation of the results of physical and chemical analysis for C1 and CR after 1, 7, 30, 90, and 180 days of storage at 4 °C, 20 °C, and 40 °C.

	Days	1 d.	7 d.			30 d.			90 d.			180 d.
	temp.	----	4 °C	20 °C	40 °C	4 °C	20 °C	40 °C	4 °C	20 °C	40 °C	4 °C	20 °C	40 °C
C1	η5s−1	18.09	19.21	19.22	20.86	17.76	19.84	20.78	23.08	22.14	17.49	23.084	19.81	17.129
	η50s−1	2.4	2.62	2.65	2.73	2.64	3.07	3.17	2.86	3.02	2.68	2.86	2.86	2.67
	d	0.986 ± 0.002	0.992 ± 0.001	0.990 ± 0.002	0.997 ± 0.001	0.996 ± 0.001	0.999 ± 0.003	0.995 ± 0.002	1.002 ± 0.001	0.998 ± 0.004	1.012 ± 0.003	1.000 ± 0.001	1.001 ± 0.001	1.001 ± 0.001
	Sf	2.95 ± 0.05	2.81 ± 0.02	2.85 ± 0.0	2.81 ± 0.04	2.83 ± 0.03	2.98 ± 0.03	2.78 ± 0.02	3.01 ± 0.03	3.16 ± 0.05	3.01 ± 0.04	3.16 ± 0.04	3.29 ± 0.05	3.31 ± 0.04
	pH	6.65 ± 0.04	6.45 ± 0.02	6.50 ± 0.0	6.53 ± 0.0	6.51 ± 0.02	6.66 ± 0.0	6.63 ± 0.02	6.76 ± 0.02	6.60 ± 0.02	6.32 ± 0.04	6.52 ± 0.01	6.68 ± 0.02	6.65 ± 0.01
CR	η5s−1	17.73	19.7	20.23	16.58	15.67	21.97	13.82	21.05	21.59	19.85	23.95	15.87	18.62
	η50s−1	2.58	2.58	2.75	2.36	2.38	2.81	2.18	2.51	2.73	2.64	2.7	2.38	2.61
	d	0.986 ± 0.002	0.968 ± 0.001	0.975 ± 0.001	0.975 ± 0.002	0.986 ± 0.001	0.989 ± 0.002	0.995 ± 0.001	0.998 ± 0.002	0.989 ± 0.001	0.992 ± 0.002	0.996 ± 0.001	1.002 ± 0.001	1.006 ± 0.002
	Sf	2.75 ± 0.03	2.79 ± 0.05	2.89 ± 0.04	2.77 ± 0.03	2.820.04	2.9 ± 0.05	2.84 ± 0.04	2.970.05	2.95 ± 0.03	2.92 ± 0.02	3.36 ± 0.04	3.09 ± 0.03	3.11 ± 0.05
	pH	5.65 ± 0.01	5.76 ± 0.02	5.56 ± 0.05	5.76 ± 0.03	5.81 ± 0.04	5.76 ± 0.04	5.63 ± 0.04	5.80 ± 0.03	5.76 ± 0.02	5.55 ± 0.02	5.72 ± 0.3	5.68 ± 0.03	5.65 ± 0.04

η₅s⁻¹ (Pa·s)—viscosity measured at a shear rate of 5 s⁻¹, η₅₀s⁻¹ (Pa·s)—viscosity measured at a shear rate of 50 s⁻¹, d (g/mL)—density, Sf (mm²/g)—spreadability index, and pH (-)—pH value.

and

Table 4. Average droplet size of the oil phase for C 1 and CR after 1, 7, 30, 90, and 180 days of storage at 4 °C, 20 °C, and 40 °C.

	Days	1 d.	7 d.			30 d.			90 d.			180 d.
	temp.	----	4 °C	20 °C	40 °C	4 °C	20 °C	40 °C	4 °C	20 °C	40 °C	4 °C	20 °C	40 °C
C1	average	3.63	3.66	3.68	3.63	3.65	3.67	3.71	3.67	3.77	3.73	3.67	3.75	3.76
	min.	1.72	1.54	1.02	1.65	1.58	1.84	2.05	2.04	1.8	1.27	1.6	1.94	2.29
	max	11.98	11.98	11.94	11.15	12.10	11.97	11.88	12.64	12.06	12.90	13.51	13.67	13.73
	sd	1.56	1.55	1.67	1.43	1.80	1.53	1.22	1.74	1.31	1.5	1.75	1.48	1.89
CR	average	4.10	4.13	4.14	4.05	4.07	4.15	4.07	4.15	4.17	4.43	4.47	4.45	4.76
	min.	2.12	2.05	2.43	2.08	2.36	2.2	2.09	2.24	2.58	2.57	2.6	2.99	3.29
	max	8.98	9.19	6.94	9.15	6.10	9.97	13.88	10.94	9.67	9.79	10.51	10.67	17.73
	sd	1.16	1.58	0.97	1.53	0.86	1.32	1.79	1.34	1.28	1.15	1.85	1.18	1.68

.

Long-term stability testing of cream C1 and the reference cream (CR) showed that both products remained stable throughout the test period, with no changes in color or odor. Centrifugal tests showed no signs of phase separation. There were no statistically significant changes in oil-phase droplet size, viscosity, pH, or spreadability index in the comparative analysis of both creams. Both creams exhibited similar patterns of change over time, as confirmed by the linear regression model.

3.3. Evaluation of the Efficacy of Common Bean (Phaseolus vulgaris L.) Sprout Micellar Extract Cream Under In Vivo Conditions

The study of skin parameters, using advanced measuring equipment, allows for a detailed assessment of skin condition and monitoring of the effects of cosmetics [24,25,26,27,28,29,30,31,32,33,34,35]. Precise measurements of hydration [24,25,26], elasticity [27,28,29,30], sebum levels [31,32], and pigmentation [33,34,35] are key to understanding the aging process and the effectiveness of cosmetic products.

Using the MPA device, the Multi-Probe Adapter Systems (Courage + Khazaka Electronic GmbH, Köln, Germany), equipped with Corneometer^® CM 825, Sebumeter^® SM, Cutometer, and Mexameter^® probes, it was possible to precisely measure skin hydration, sebum levels, elasticity, and pigmentation. Such a multi-parameter analysis allowed for a precise determination of the skin condition and the effectiveness of the innovative cream with micellar extract of common bean sprouts (P. vulgaris).

Efficacy tests of the cream were performed on a group of volunteers with mature skin.

The results of skin hydration, elasticity (R2 and R5), melanin index (MI), erythema index (EI), and sebum secretion measurements, along with their respective statistical analyses, are summarized in

Table 5. Characteristics of the groups in terms of hydration.

	Placebo n = 15	Extract n = 15	CR n = 15	Summary n = 45	p = Value/ Statistically Significant Between Group
Measurement 1 (M1)
Average (±SD)	a 49.38 (11.1)	a 48.81 (8.45)	a 50.55 (9.07)		No
Measurement 2 (M2)
Average (±SD)	b 50.14 (10.65)	b 53.50 (10.63)	b 51.72 (11.35)		No
∆%	+1.54	+9.61	+2.31
Measurement 3 (M3)
Average (±SD)	c 50.74 10.48	c 57.48 10.09	c 54.34 9.48		No
∆%	+2.75	+17.76	+7.5
Measurement 4 (M4)					df 2.42, F = 4.74
Average (±SD)	d 51.12 1 9.56	d 59.70 2 9.07	d 58.68 3 9.06		1,2 0.04 1,3 0.04
∆%	+3.52	+22.31	+16.08
p–value Statistical significant within the group.	a.d 0.03	a.b 0.012 a.c 0.0012 a.d 0.0008	a.c 0.026 a.d 0.001

^a—measuremet 1, ^b—measurement 2, ^c—measuremet 3, ^d—measurement 4; ¹ Placebo, ² Extract, ³ CR; df—degrees of freedom, F (F-ratio, F-value)—the test statistic in ANOVA.

and

Table 6. Characteristics of the groups in terms of skin elasticity parameter R2 and R5.

	Placebo n = 15	Extract n = 15	CR n = 15	Statistically Significant Between Group
Measurement 1–parameter R2
Average ± SD	a 70.53 ± 6.49	a 71.41 ± 7.24	a 71.93 ± 9.07	No
Measurement 2–parameter R2
Average ± SD	b 73.02 ± 5.33	b 74.22 ± 7.17	b 72.76 ± 4.75	No
∆%	+3.53	+3.93	+1.15
Measurement 3–parameter R2
Average ± SD	c 75.90 ± 3.37	c 77.76 ± 5.63	c 75.18 ± 5.28	No
∆%	+7.61	+8.89	+4.52
Measurement 4–parameter R2
Average ± SD	d 76.53 ± 3.4 1	d 80.91 ± 5.07 2	d 76.52 ± 5.01 3	df(2.42), F = 4.35 1,2 0.04
∆%	+8.5	+13.3	+6.38	2,3 0.04
p–value within the group	a.c 0.04 a.d 0.01	a.c 0.005 a.d 0.0002	a.d 0.048
		Measurement 1–parameter R5
Average ± SD	a 62.41 ± 7.22	a 61.94 ± 7.96	a 67.17 ± 7.12	No
Measurement 2–parameter R5
Average ± SD	b 63.02 ± 8.57	b 64.28 ± 5.76	b 63.38 ± 6.47	No
∆%	+1.76	+3.78	−5.66
Measurement 3–parameter R5
Average ± SD	c 60.54 ± 8.281	c 67.34 ± 8.13 2	c 65.57 ± 5.47 3	df(2.42), F = 3.34 1,2 0.04
∆%	−3.01	+8.71	−2.39
Measurement 4–parameter R5
Average ± SD	d 63.86 ± 8.37	d 69.58 ± 6.86	d 69.74 ± 7.32	No
∆%	+2.32	+12.33	+3.82
p–value within the group		a.d 0.008	b.d 0.01

^a—measuremet 1, ^b—measurement 2, ^c—measuremet 3, ^d—measurement 4; ¹ Placebo, ² Extract, ³ CR; df—degrees of freedom, F (F-ratio, F-value)—the test statistic in ANOVA.

and Figure 1, Figure 2 and Figure 3.

The principle of the Corneometer^® CM 825 is to assess the degree of hydration by measuring the electrical capacitance of the superficial stratum corneum [24,25]. Measurement results are expressed in arbitrary units (a.u.) on a scale from 0 to 120, whereby the moisture-related skin types are classified as follows: very dry skin is characterized by corneometer units below 30, dry skin between 30 and 40, and normal skin with values higher than 40 a.u. [26].

Hydration levels were analyzed using repeated-measures ANOVA, followed by Tukey’s HSD for within-group comparisons. Between-group differences were evaluated using ANOVA with Tukey’s post hoc test. A p-value of <0.05 was considered statistically significant.

The measurement results of skin hydration clearly indicate that regular use of the cream with micellar extract of common bean sprouts (Phaseolus vulgaris) statistically significantly improves skin hydration. Significant improvements were observed compared to baseline: after 4 weeks, skin hydration increased by (+9.61%); after 8 weeks, by (+17.76%); and, after 12 weeks of use, by (+22.31%). In the CR group, skin hydration also improved significantly at all measured time points: after 4 weeks by (+2.31%), 8 weeks (+7.5%), and 12 weeks of use by (+16.08%). In contrast, the placebo group showed significant improvement only after 12 weeks by (+3.52%). Between-group comparisons revealed that skin hydration in the extract group was significantly higher than in the placebo group after 12 weeks. However, no statistically significant differences were found between the CR group and the reference cream group at any time point.

The study of skin elasticity parameters provides valuable insights into age-related changes and allows for the assessment of cosmetic product efficacy [27,28]. The most commonly used device for measuring skin elasticity is the Cutometer^® probe [29]. This device measures eight parameters related to skin elasticity, including R0 (stretch/firmness), R1/R4 (recovery capacity), R2 (overall skin elasticity), R5 (net elasticity), R6 (viscoelasticity), R7 (ratio of elastic recovery to total strain), and R8 (total relaxation after pressure) [30]. Skin elasticity was measured using the Cutometer^® Dual MPA 580 probe. The two most characteristic parameters (R2 and R5) were selected to analyze the effectiveness of the cream with micellar extract of common bean (P. vulgaris) sprouts.

Elasticity parameters (R2 and R5) were analyzed using repeated-measures ANOVA, followed by Tukey’s HSD for within-group comparisons. Between-group differences were evaluated using ANOVA with Tukey’s post hoc test. A p-value of <0.05 was considered statistically significant. The parameters R2 and R5 reflect the skin’s total elasticity and the ability to return to its original state after deformation, respectively. The skin elasticity tests (R2 and R5 parameters) showed that the cream with micellar extract of common bean (P. vulgaris) sprouts statistically significantly improved total elasticity (R2) after 8 weeks by (+8.89%) and after 12 weeks by 13.30%. In the placebo group, a statistically significant increase was observed after 8 weeks (+7.61%) and 12 weeks (+8.50%). In the CR group, a statistically significant increase was observed only after 12 weeks (+6.38%). Statistically significant differences between the placebo and extract groups were observed after 12 weeks. The effect of the cream with extract and the reference cream on the improvement of the R5 parameter was statistically significant only after 12 weeks of use, while no improvement in the R5 parameter was observed in the case of the placebo cream. Statistically significant differences in the improvement of the R5 parameter were noted between the placebo cream and the cream with the extract only after 8 weeks of use. In the remaining cases, no statistically significant differences were noted.

Skin type is a complex parameter primarily determined by pigments such as hemoglobin, melanin, bilirubin, and carotene. The levels of these pigments can change in response to UV radiation and certain substances, including medications. When analyzing skin color, two key indices are evaluated: the Erythema Index (EI) and the Melanin Index (MI). Erythema, represented by EI, refers to localized skin redness caused by the dilation of superficial blood vessels. MI, on the other hand, reflects the amount of melanin, a natural pigment found in living organisms [34].

The Sebumeter^® SM 815 cassette directly measures skin oiliness. The instrument operates based on the principle of spot photometry. The cassette features a matte film with specific opalescence properties. When covered with a lipid layer, the film becomes transparent under light. The measurement, expressed in μg sebum/cm², reflects the difference in transparency of the tape before and after skin contact. The measurement result is the difference in the transparency of the tape before and after contact with the skin, expressed in the range of 0–350 μg of sebum/cm² [31,32]. Sebum levels were measured at three different locations on the forehead and the result is presented as the average of these measurements.

Statistical analyses for the Melanin Index (MI) and Erythema Index (EI) and for the Sebum Parameter were performed using, for within-group comparisons, repeated-measures Friedman’s test and between-group differences were analyzed using the Kruskal–Wallis test with post hoc Mann–Whitney U tests used where applicable. A p-value of <0.05 was considered statistically significant.

The measurement of the Melanin Index demonstrated a slight lightening effect over time within the tested groups. For both the cream with the extract and the reference cream, the skin lightening effect was (−7.3%) for the cream with the extract, which was statistically significant, and (−6.4%) for the reference cream, which was not statistically significant. Comparing the skin lightening effect between the groups, no statistically significant changes were observed.

Regarding the reduction in skin redness (Erythema Index), a decrease in redness was noted at (−3.68%), (−12.1%), and (−10.36%) for the placebo cream, the cream with the extract, and the reference cream, respectively. However, these values were not statistically significant. No statistically significant changes were observed when comparing the effect of the creams on redness levels between the groups at any stage of the study.

The analysis of sebum secretion on the skin’s surface did not show any statistically significant effect of the tested formulations on this parameter at any stage of the study.

4. Discussion

The conducted research confirmed the high effectiveness of cream with micellar extract of common bean (Phaseolus vulgaris L.) sprouts as an innovative cosmetic ingredient for mature skin care.

The decision to select a reference cream (CR) from among the many available on the market was thoughtful and carefully evaluated for effectiveness. We aimed to choose a product with confirmed antiwrinkle, firming, and moisturizing effects to provide a reliable basis for comparison with our cream containing a natural extract from common bean sprouts (P. vulgaris). Our goal was to also demonstrate that the innovative formula of our product, based on a natural, plant-derived ingredient, is comparable to the antiwrinkle, firming, and moisturizing effects of creams with costly synthetic active ingredients. It is worth noting that synthetic ingredients, such as 1-Methylhydantoin-2-Imide, despite their beneficial moisturizing properties, may exhibit an irritating potential, further supporting the advantages of natural alternatives in cosmetic formulations.

All tested creams, including the reference, were stable o/w emulsions, with no signs of phase separation. The occlusive properties, crucial for predicting moisturizing efficacy, were comparable across formulations and the reference cream, with occlusion rates of approximately 50%. While these values indicate moderate occlusion, Wissing [13] classifies coefficients above 60% as highly occlusive, suggesting room for improvement in enhancing skin hydration.

The droplet size observed in this study is typical and consistent with values reported in the literature [18,19].

The properties of a cosmetic cream, such as rheology, stability, texture, and color, are largely determined by the droplet size of the dispersed phase. Finer droplets lead to higher viscosity, better stability, brighter appearance, smoother texture, and more favorable application properties, such as easier spreading and higher absorption rate [18,19]. The pH of all formulations was also determined and found to be close to the natural pH of the skin, making these creams safe for the skin [20]. The preparations showed small differences in dynamic viscosity and comparable thixotropy. The obtained rheological results indicate that all formulations will behave similarly during application, will be easy to dispense from the container, spread easily, and absorb quickly [15,16,21,22]. These properties were also confirmed in complementary spreadability and slip tests. The exception was cream C6, which, due to its 6% emulsifier content and high concentration of consistency-forming agents, exhibited higher apparent viscosity and a high yield stress value. This translated into a lower spreadability coefficient and a higher force required to spread the cream. The parameters of C6 cream suggest it is suitable for use as an eye cream or regenerating night cream [22]. There is a relationship between the rheological properties of cosmetic formulations and sensory perception. Cosmetic formulations are more favorably evaluated when they exhibit pseudo-plastic flow according to the power law model [22].

Long-term stability and accelerated aging tests are crucial for assessing the quality and safety of cosmetics [23]. Long-term stability testing of cream C1 and the reference cream showed that both products remained stable throughout the test period. The stability tests conducted on the cream with micellar extract from common bean sprouts enabled its testing in a study involving volunteers.

Modern research confirms that the use of advanced measuring equipment tools is essential in dermatology and cosmetology to provide adequate skin care and effectively counteract the aging process. Mature skin is characterized by numerous changes resulting from both internal biological processes and external environmental factors. The main characteristics of mature skin include loss of elasticity, decreased hydration, and the appearance of wrinkles and discoloration. Skin aging is the result of complex genetic and hormonal processes, as well as exposure to UV radiation and environmental pollutants, which leads to a gradual deterioration of the skin’s condition [36].

The increase in skin hydration in each of the tested groups resulted from the presence of emollients in the composition of the creams, which retain moisture in the stratum corneum through occlusion. This, combined with regular use of the preparation, contributed to the improvement of skin hydration. Muhammad Tahir Khan et al. [6] also assessed the effect of a cosmetic cream containing an extract of powdered common bean seeds (P. vulgaris) on skin hydration. They observed that, both after applying a placebo cream and a cream with an extract of powdered bean seeds, there was a significant change and the skin became moisturized. They concluded that this increase in moisture content in the stratum corneum was caused by the presence of vitamin C in the extract and the presence of fatty acids in the cream base of the cosmetic, which have a moisturizing effect. The influence of various factors on skin hydration was also demonstrated by Trojahn et al. [37]. They used the Corneometer^® probe to measure skin hydration. They showed that skin hydration decreases significantly with age as part of the natural aging process, which is a consequence of both internal aging processes and external factors such as sun exposure and environmental pollution. This research highlights the importance of maintaining skin hydration as a key factor in the aging process. Choi and co-authors [30], in their study, assessed the influence of skin hydration on the formation of wrinkles. They used both the Cutometer^® and Corneometer^® CM 825 probes. They showed that lack of proper skin hydration leads to reduced skin elasticity, resulting in the faster appearance of wrinkles, while maintaining an appropriate level of skin hydration delays the aging process.

Skin elasticity, determined by elastin and collagen fibers, is a key indicator of its viscoelasticity. As the skin ages and under the influence of various external factors, the structure of these fibers becomes more rigid, leading to skin sagging and the formation of wrinkles. Therefore, measuring skin elasticity serves as an important indicator of its biological age [38].

The skin elasticity parameters studied enable the analysis of age-related changes and the evaluation of cosmetic efficacy [27,28]. For skin elasticity testing, the Cutometer^® probe is most commonly used [29].

The skin phototype primarily depends on the pigment content, including hemoglobin and melanin. It is an important indicator of the skin’s response to UV radiation and certain chemicals, including drugs [33]. The Mexameter^® MX 18 probe uses different wavelengths to measure the content of hemoglobin and melanin in the skin. The measurement results are expressed as the Erythema Index (EI) and the Melanin Index (MI) [34].

The Mexameter^® probe provides reproducible and highly precise measurements, with minimal impact from environmental variables [35].

The brightening effectiveness of our cream with an extract of common bean (P. vulgaris) was comparable to the reference cream. The brightening effect of this type of cream was also confirmed in studies by Muhammad Tahir Khan et al. [6]. The participants’ skin did not exhibit features characteristic of vascular skin. Therefore, while a reduction in erythema was observed, it did not reach statistical significance.

With respect to the sebostatic effect, no statistically significant differences in sebum levels on the skin surface were observed between the study groups. This is likely because the average age of the participants was 51.8 years and none had oily skin. At this age, reduced sebum secretion is natural and typical, which likely made any sebostatic effect of the cream with the extract neither visible nor necessary. The cream with micellar extract from common bean sprouts demonstrated high efficacy in skin hydration, improving elasticity and reducing discoloration. All volunteers completed the study and no cases of allergy or skin irritation were observed. Previous research by other scientists [39] suggests that the use of micellar extracts in cosmetics reduces their skin irritation potential and enhances the availability of active ingredients.

The cream formulated with the extract of common bean sprouts appears to be a promising cosmetic product. However, it is important to note that the study’s reliability could be enhanced by conducting the research with a larger number of volunteers. Additionally, the accuracy of self-reported compliance by participants, especially with the placebo cream, cannot be fully guaranteed. While participants agreed to adhere to the prescribed application protocol, there is always a possibility of deviations, such as irregular use, concurrent use of other cosmetic products, or undergoing skin treatments, all of which could influence the study outcomes. These factors should be considered when interpreting the results.

5. Conclusions

Our research has shown that the innovative cream formulation based on micellar bean sprout extract has moisturizing properties, improves skin elasticity, and provides a brightening effect when used regularly. The results achieved indicate that the proposed cream with micellar extract as an ingredient enriching the formula can serve as an effective solution for the care of dry, sensitive, and mature skin, thus meeting the growing requirements of modern consumers looking for natural and effective cosmeceuticals. Rheological and stability analyses have shown that our product is characterized by high quality of application and durability, which makes it suitable for market introduction. Therefore, we plan to continue research to assess the effect of bean sprout extract on dermatological problems such as rosacea or skin discoloration, as well as to assess potential adverse reactions to the extract, especially in people with sensitive or allergy-prone skin from different age groups.