INTRODUCTION:

Uneven melanin production is a major medical and cosmetic problem associated with skin hyperpigmentation. Kojic acid, a naturally occurring metabolite generated by several Aspergillus and Penicillium species, has become well-known among the medications used to treat hyperpigmentation due to its strong depigmenting effects.

It works by blocking melanogenesis by chelating copper inside the tyrosinase enzyme's active site.¹Kojic acid's improved bioavailability, ease of application, and potential for continuous release make it a common ingredient in topical gels. A common 10g kojic acid gel formulation for topical application consists of a synergistic blend of active and supportive components that work together to improve skin tone, lessen dark spots, and provide antioxidant protection.

MATERIAL USED:

(1) KOJIC ACID:

Kojic acid (5-hydroxy-2-hydroxymethyl-4H-pyran-4-one) was initially discovered in 1907 and is an organic acid that is produced by fermenting fungi of many genera, including Aspergillus and Penicillium. Since tyrosinase is the primary enzyme involved in the formation of melanin, it is most frequently used as a skin depigmenting agent. Additionally, the depigmenting mechanism of kojic acid involves leucocyte regulation, copper-chelating activity, and free radical scavenging. In addition, anti-inflammatory, antibacterial, and antioxidant properties were noted. Since the 1940s, reports of toxicity and antimicrobial research have been made, but the mechanisms of action are still unclear.

In addition, a large number of patents pertaining to kojic acid or its derivatives that are either related to its manufacturing or to its usage in medicine and cosmetics have been filed. A 1987 patent study showed that hydroquinone and kojic acid worked in concert, especially for their anti-inflammatory or depigmenting properties. Additionally, a 2016 patent study demonstrated the antidermatophytic, antimycobacterial, antityrosinase, and antioxidant properties of Mannich bases generated from kojic acid. Despite the large number of registrations, which date back to the 1950s, fresh patent documents are still found nowadays.²

Fig. 1: Kojic Acid.

(2) NIACINAMIDE (Vit. B3):

Niacinamide, sometimes referred to as vitamin B3, is a multipurpose and well studied skincare component that is believed to improve skin tone and fortify the skin's natural defenses. By preventing melanosomes from moving from melanin cells to keratin Cell it significantly lessens hyperpigmentation and evens out skin tone. For people who suffer from post-inflammatory hyperpigmentation, dullness, or dark patches, this makes it very advantageous. Furthermore, by promoting the stratum corneum's production of ceramides and free fatty acids, niacinamide strengthens the barrier's ability to retain moisture and lower transepidermal water loss. The skin gets stronger and less resistant to irritation as a result. Because it can result in a noticeably smoother, healthier, and brighter complexion, niacinamide is a key component of many therapeutic and cosmetic procedures.³

(3) LICORICE ROOT:

Fig. 2: Licorice root

A common botanical component in skincare products, licorice extract is made from the root of Glycyrrhiza glabra and is prized for its anti-inflammatory and brightening qualities. Glabridin, one of its main active ingredients, helps to even out skin tone and lessen hyperpigmentation by blocking the activity of the enzyme tyrosinase, which produces melanin. Additionally, licochalcone A, which has strong anti-inflammatory and antioxidant properties, is found in licorice and can help soothe inflamed skin, such as that caused by rosacea, acne, or atopic dermatitis (AD). Furthermore, by lowering redness and enhancing general clarity, licorice aids in skin relaxation. It is commonly utilized in formulas intended to treat pigmentation, post-inflammatory markings, and sensitive skin because of its dual action—calming and brightening.⁴

(4) ALOE VERA:

Fig. 3: Aloe vera.

Aloe vera's calming, moisturizing, and restorative qualities make it a popular plant in dermatology. Acemannan, which is important for skin regeneration and moisture retention, is one of the many vitamins, enzymes, minerals, amino acids, and polysaccharides found in the clear gel that is extracted from its leaves. Sunburn, wound healing, and other skin irritations can all be effectively managed with aloe vera's well-known anti-inflammatory and antioxidant properties. It promotes the skin barrier, speeds up tissue regeneration, and lessens redness. Because it is mild and non-comedogenic, it can be used on sensitive or acne-prone skin, reducing outbreaks without blocking pores.⁵

(5) CARBAPOL 934:

Many industries use carbopol, a water-soluble polymer, as an emulsifying, stabilizing, suspending, thickening, and geling agent. There are various grades of carbopol that are used extensively in the production of toiletries and cosmetics, such as gels, lotions, and creams, as well as detergents and air fresheners. Carbomeres are used as a rheology modifier in pharmaceutical formulations that are liquid or semisolid. Creams, gels, lotions, and ointments areamong the formulations used in vaginal, topical, opthalmic, and rectal preparations.⁶

(6) TRIETHANOLAMINE:

This organic compound is viscous and a combination of a triol and a tertiary amine. Three alcohol groups make up a triol molecule. A potent base is triethanolamine. Triethanolamine is mostly utilized in the production of surfactants, like emulsifiers. It is frequently used as an ingredient in both consumer and industrial product formulations. In addition to adjusting and buffering the pH and neutralizing fatty acids, triethanolamine also solubilizes oils and other substances that are not entirely soluble in water. In some situations, triethanolammonium salts are more soluble than alkali metal salts that might be used otherwise, and they produce fewer alkaline products than if the salt were made with alkali metal hydroxides. Sunscreen lotions, dishwashing liquid, liquid laundry detergents, general cleaners, hand sanitizers, polishes, metal working, fluid paints, shaving cream, and painting supplies are among the common products that contain triethanolamine.⁷

(7) METHYL AND PROPYL PARABEN:

Preservatives like methylparaben and propylparaben are used in skincare and cosmetics to prevent the growth of mold and bacteria, extending the shelf life and ensuring product safety. Propylparaben is effective against mold, whilst methylparaben combats bacteria. Health authorities have approved them as safe and they are used in tiny dosages. Studies demonstrate they are safe when taken properly, despite some people's concerns that they may cause skin irritation or alter hormones. However, due to consumer concerns, many firms now produce paraben-free goods.⁸

EXTRACTION PROCEDURE OF LICORICE EXTRACT:

Dried licorice root, wash it, and then grind it into coarse poweder.

40 gm of licorice root powedred combined with 250ml ethanol.

Allow the mixture soak for specified time (48 hrs.).

The mixtured was filtered by using whatman no.1 filter paper.

After collected dilute extract.

FORMULATION OF GEL:

Gel was prepared by using 1.5gm of carbapol and dispersed uniformly in 30ml of distilled water with continuous stirring by using mechanical stirrer. Avoiding air entrapment and allowed to soak overnight. Next day triethanolamine was added drop by drop with constant stirring till adjust pH to 5.0-5.5 to ensure skin compatibility and gel base was formed. Triethanolamine was added slowly to the dispersion with continuous stirring until a gel was formed. Then separately another beaker dissolve kojic acid, niacinamide, with gently heating (below 50^.c) this mix. and licorice root extract added to the gel base slowly with contineous stirring. Methyl and Propyl paraben as presevative and aloe vera gel was added and complete the volume with distilled water.

Table 1: Composition of Developed formulation.

Carbapol 934	1.5gm	Gelling agent
Triethanolamine	q.s.	pH adjuster andgel thickner
Methyl and Propyl paraben	0.3gm	Preservative
Kojic acid	0.6 gm	Skin lightning agent.
Niacinamide (vit. B3)	1.2gm	Anti-inflammatory, even skin tone.
Licoroce root extract	3ml	Natural depigmentation agent.
Aloe vera	15gm	Soothing gel base.
Purified water	30 ml	Vehicle / base

Fig. 4: Gel formulation.

EVALUATION PARAMETERS:

I. Clarity of Gel: Visual inspection is used to determine the gel's clarity.

II. Physical Appearance: Physical parameters such as color, consistency were checked visually.

Color: Through visual inspection, the formulation's color was verified.

Consistency: Applying the formulation to the skin allowed for the consistency to be verified.⁹

III. Homogenisity: After the gels were placed into the container, the homogeneity of each created gel formulation was examined visually. They were examined to determine whether any aggregates were present and how they looked. It was reported that the gel formulation was homogeneous.

IV. Measurement of pH: The gel formulation's pH was measured with a digital pH meter. After dissolving 1g of gel in 10ml of distilled water, let it sit for two hours. Following three full dips of the glass electrode into the gel system, the pH of the formulation was measured, and the average readings were then reported. It was mentioned what the gel formulation's pH was.¹⁰

V. Spreadability: Spreadability is defined as the amount of time, measured in seconds, it takes for two slides to separate the gel that is positioned between them when a specific stress is applied. Better spreadability results from a shorter time required to separate two slides. Spreadability is calculated by using the formula:

S = M × L / T

Where

M = Weight tied to upper slide

L = Length of glass slides

T = Time taken to separate the slides Spreadabilty of gel formulation.

VI. Drug Content: 10ml of an appropriate solvent was combined with 1g of the produced gel. After filtering the stock solution and measuring absorbance, aliquots with varying concentrations were made using appropriate dilutions. The equation, which was derived from linear regression analysis of the calibration curve, was used to determine the drug content.¹¹

Drug content: (Absorbance/Slope)* Dilution factor *(1/1000)

Table 2: Evalution parameter result.

Evaluation parameter	Results
Clarity	+++
Physical apperance	Color: Pastel yellow
Physical apperance	Consistency: Consistent
Homogenesity	Good
pH	5.2
Spreadability	6.5
Drug content	82.75%

CONCLUSION:

The gel formulation that was created with licorice root extract, niacinamide, kojic acid, and aloe vera showed promising properties that made it appropriate for topical use. The gel's exceptional clarity (+++), homogeneity, and consistent consistency guaranteed that the active components were distributed evenly. The formulation's pH of 5.2 minimizes the chance of irritation because it is in harmony with skin physiology. A spreadability of 6.5 seconds suggests that the application is sufficiently simple. The effective integration of active molecules was confirmed by the drug content, which was 82.75%. Overall, the formulation has promise as a depigmenting and skin-brightening agent with respectable physicochemical characteristics and room for additional dermatological uses.

REFERENCES:

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3. Draelos ZD. The effect of niacinamide on reducing cutaneous pigmentation and suppression of melanosome transfer. Br J Dermatol. 2002; 147(1): 20–31.

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6. https://en.wikipedia.org/wiki/Polyacrylic_acid.

7. https://en.wikipedia.org/wiki/Triethanolamine.

8. Darbre PD, Harvey PW. Paraben esters: review of recent studies of endocrine toxicity, absorption, esterase and human exposure, and discussion of potential human health risks. J Appl Toxicol. 2008; 28(5): 561–78.

9. Monika Chandrakant Farde, Bhakti Anil Gaonkar, Dharam Atul Gharat, Sakshi Pritam Gharat, Ritik Rakesh Gupta, Vinita Yadav and Sonali Uppalwar. Review Article On: Mouth Ulcer Gel. International Journal of Pharmaceutical Research and Applications. 2023; 8(2): 1361-1374.

10. Sakshi B. Jadhav, Shivtej S. Jadhav, Sourav A. Jadhav, Trupti M. Jamadar, Vrushali S. Jamdar, P. S. Kadane. Formulation and Evaluation of Polyherbal gel for Management of Mouth Ulcer. international Journal for Multidisciplinary Research. 2024; 6(4); 1-16.

11. Chandrasekar R., G. Satheesh Kumar. Formulation and Evaluation of a Poly Herbal Anti- acne gel. Research Journal of Topical and Cosmetic Sciences. 11(1).

Received on 19.05.2025 Revised on 11.08.2025

Accepted on 30.10.2025 Published on 18.04.2026

Available online from April 25, 2026

Research J. Topical and Cosmetic Sci. 2026; 17(1):31-34.

DOI: 10.52711/2321-5844.2026.00007

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