ALOE VERA (Transcription for presentation)

I.​ Active Ingredient, Source, and Mechanism of Action of Aloe Vera

●​ Active Ingredients: Aloe vera contains several bioactive compounds, including

polysaccharides (such as acemannan), glycoproteins, anthraquinones (e.g., aloin
and emodin), vitamins (A, C, E, and B12), enzymes, minerals, and amino acids.​

●​ Source: Aloe vera is a cactus-like plant that grows in hot, dry climates. It is derived
from the leaves of the Aloe barbadensis miller plant, a succulent plant belonging to
the Asphodelaceae (Liliaceae) and it is a succulent species native to the Arabian
Peninsula but widely cultivated in tropical and subtropical regions. The gel and latex
extracted from its leaves are commonly used in medicine, cosmetics, and skincare
products.​

●​ Mechanism of Action:​

○​ Wound Healing & Anti-Inflammatory Effects: Aloe vera gel contains

polysaccharides, particularly acemannan, which enhance fibroblast activity,
collagen synthesis, and cellular regeneration, promoting wound healing. It
also inhibits pro-inflammatory cytokines, reducing inflammation.
○​ Antimicrobial Properties: Aloe vera contains anthraquinones (e.g., aloin,
emodin) with antibacterial, antiviral, and antifungal effects, helping prevent
infections.
○​ Moisturizing & Skin Protection: The gel forms a protective barrier, hydrates
the skin, and enhances water retention, making it effective for burns and dry
skin.
○​ Laxative Effect: Aloe latex contains anthraquinones (especially aloin), which
stimulate intestinal peristalsis and increase water secretion, acting as a
natural laxative.
○​ Antioxidant & Immune Modulation: The plant’s vitamins (A, C, E) and
phenolic compounds scavenge free radicals, reducing oxidative stress.
Additionally, acemannan enhances macrophage activity, boosting the immune
response.

II. Aloe Vera Products

1.​ Aloe Vera Gel
1.1 Ingredients
Functional Ingredient Function
Group

Aloe Vera Aloe Barbadensis Leaf Provides nutrients,

Extract Extract soothes the skin

Gelling Agent Xanthan Gum, Algin Creates gel texture,

increases viscosity

Preservatives Sodium Benzoate, Potassium Prevents bacterial

Sorbate, Benzyl Alcohol, growth, extends shelf
Benzoic Acid, Sorbic Acid life

Humectant Glycerin Moisturizes, softens

the skin

pH Adjuster Citric Acid Stabilizes pH level

1.2 Functions of products​

1. Moisturizing and Softening the Skin
Glycerin helps attract moisture from the environment and retain hydration in the skin,
preventing dryness.
Aloe Barbadensis Leaf Extract provides water and natural nutrients, keeping the skin plump
and soft.

2. Soothing and Skin Recovery

Aloe Barbadensis Leaf Extract has anti-inflammatory properties, helping to calm irritated,
red, or sunburned skin.
Xanthan Gum & Algin create a smooth gel texture that feels light on the skin without causing
stickiness.

3. Skin Protection and Antibacterial Properties

Preservative system (Sodium Benzoate, Potassium Sorbate, Benzoic Acid, Sorbic Acid,
Benzyl Alcohol) prevents bacterial and fungal growth, ensuring safe usage.
Aloe Vera has mild antibacterial properties, helping to cleanse the skin and prevent
acne-causing bacteria.

4. pH Balancing and Oil Control

Citric Acid adjusts the product’s pH to a suitable range (~5.0 - 6.0), preventing irritation or
excessive dryness.
This formula does not contain oils or fragrances, making it suitable for oily, sensitive, and
easily irritated skin.

5. Skin Regeneration and Healing Support

Aloe Vera contains compounds that stimulate cell regeneration, aiding skin recovery from
minor damage such as sunburn, scratches, or irritation.
Glycerin retains moisture, creating an optimal environment for faster healing and healthier
skin.

1.3 Preparation ( based on https://www.researchgate.net/publication/362618635_Preparation_of_Aloevera_Gel )

Step 1: Prepare the Base Gel Solution
Weigh Xanthan Gum and Algin, then slowly disperse them into purified water or Aloe
Barbadensis Leaf Extract while stirring continuously to prevent clumping.
Allow the mixture to swell for 30 minutes.

Step 2: Dissolve Preservatives and Humectants

Dissolve Glycerin, Sodium Benzoate, Potassium Sorbate, Benzoic Acid, Sorbic Acid, and
Benzyl Alcohol in water or Aloe Vera extract, stirring well.
Add this solution to the base gel mixture while continuously stirring.

Step 3: Adjust pH and Finalize the Product

Check the product's pH, which should typically be in the range of 5.0 - 6.0.
If necessary, gradually add Citric Acid until the desired pH is achieved.
Continue stirring gently to ensure a homogeneous gel.

Step 4: Packaging and Storage

Check the viscosity and stability of the gel.
Fill into appropriate packaging (plastic bottles or glass jars).
Store in a cool, dry place, away from direct sunlight to maintain product quality.

2.​ Aloe Vera Sunscreen

2.1 Ingredients
Functional Group Ingredient Function

Sunscreen Agents (Active Homosalate (8.5%) UVB filter, protects skin from
Ingredients) sunlight

Octisalate (5.0%) Enhances UVB protection,

improves formula absorption

Octocrylene (10.0%) UVB/UVA protection,

stabilizes Avobenzone if
present

Zinc Oxide (12.0%) Broad-spectrum protection,

shields against UVA/UVB

Moisturizing & Soothing Aloe barbadensis leaf juice Hydrates and soothes the skin
Agents

Caprylyl Glycol Humectant, mild antibacterial

agent

Ethylhexylglycerin Paraben alternative

preservative, mild moisturizer

Propanediol Humectant, enhances active

ingredient absorption

Tocopheryl Acetate (Vitamin E Antioxidant, nourishes the skin

Acetate)
 Emollients & Skin Cetearyl Ethylhexanoate Emollient, provides a smooth
Conditioning Agents skin feel

Propylheptyl Caprylate Emollient, improves

spreadability on skin

Emulsifiers & Formula Diisostearoyl Polyglyceryl-3 Emulsifier, helps oil and water
Stabilizers Dimer Dilinoleate mix

Hydrogenated Castor Oil Emulsifier, thickens the

formula

Magnesium Sulfate Stabilizes emulsions, adjusts

viscosity

Polyhydroxystearic Acid Helps disperse Zinc Oxide in

the formula

Preservatives & Chlorphenesin Preservative, protects against

Antimicrobial Agents bacteria and fungi

Phenoxyethanol Broad-spectrum preservative

Potassium Sorbate Preservative, inhibits mold and

yeast growth

Solvents & Lightweight Tridecane, Undecane Solvents, provide a lightweight

Texture Enhancers and non-greasy feel

Film Forming & Water VP/Hexadecene Copolymer Forms a protective film,

Resistance Agents enhances water resistance

Chelating & Stabilizing Sodium Gluconate Chelating agent, stabilizes the

Agents formula

Fragrance & Base Fragrance Provides a pleasant scent

Ingredients

Purified Water Base medium for the water

phase

2.2 Functions​
1. Protects the skin from sun damage
UVB Protection: Homosalate (8.5%), Octisalate (5.0%), and Octocrylene (10.0%) help shield
the skin from UVB rays, which are the primary cause of sunburn.
Broad-Spectrum UVA & UVB Protection: Zinc Oxide (12.0%) provides broad-spectrum
protection, preventing premature aging and reducing the risk of skin cancer.
Stabilizes the sunscreen formula: Octocrylene helps stabilize other sunscreen ingredients,
particularly Avobenzone if present.

2. Moisturizes & soothes the skin

Hydration: Aloe barbadensis leaf juice provides moisture to the skin, keeping it soft and
preventing dryness from sun exposure.
Moisture retention & enhanced absorption: Propanediol, Caprylyl Glycol, and
Ethylhexylglycerin help retain moisture and improve nutrient absorption.
Soothing & antioxidant protection: Tocopheryl Acetate (Vitamin E Acetate) nourishes the
skin and reduces free radical damage caused by UV exposure.

3. Smooth texture & easy application

Softens the skin: Cetearyl Ethylhexanoate and Propylheptyl Caprylate keep the skin smooth
and prevent roughness.
Ensures easy application & quick absorption: Propylheptyl Caprylate allows the sunscreen to
spread evenly without clumping or stickiness.

4. Forms a protective barrier & resists water

Creates a protective layer: VP/Hexadecene Copolymer forms a protective film on the skin,
making the sunscreen more resistant to water and sweat.
Lightweight & non-greasy texture: Tridecane and Undecane provide a lightweight
consistency that absorbs quickly without feeling greasy.

2.3 Preparations ( based on

https://www.researchgate.net/publication/342594611_The_Effects_of_Aloe_Vera_Gel_Addition_on_the_Effectiveness_of_Sunscreen
_Lotion )
1. Preparation of Oil Phase (Phase A)
- Weigh Homosalate, Octisalate, Octocrylene, Zinc Oxide, Cetearyl Ethylhexanoate,
Diisostearoyl Polyglyceryl-3 Dimer Dilinoleate, Hydrogenated Castor Oil,
Polyhydroxystearic Acid, Propylheptyl Caprylate, Tridecane, Undecane, VP/Hexadecene
Copolymer.
- Heat to 65-70°C and stir until a homogeneous mixture is obtained.

2. Preparation of Water Phase (Phase B)

- Dissolve Magnesium Sulfate, Potassium Sorbate, Sodium Gluconate, Propanediol in
distilled water.
- Heat to 65-70°C while stirring.

3. Emulsification
- Gradually add the water phase (B) into the oil phase (A) while stirring vigorously to form a
stable emulsion.
- Continue stirring for 15-20 minutes to ensure uniformity.
4. Adjustment and Finalization
- Cool down the mixture to 40°C.
- Add Aloe Vera Gel Extract, Caprylyl Glycol, Ethylhexylglycerin, Phenoxyethanol,
Chlorphenesin, Tocopheryl Acetate, Fragrance.
- Stir gently to ensure even distribution.

5. Quality Control and Adjustments

- Measure and adjust the pH to a range of 5.5 - 7.0 if necessary.
- Check viscosity, adhesion, dispersion, and sensory properties.

6. Packaging and Quality Testing

- Package the sunscreen in UV-protected bottles or tubes to maintain stability.
- Conduct necessary tests such as SPF testing, PA testing, and water resistance evaluation.

3.​ Aloe Vera Lotion

3.1 Ingredients

Functional Group Ingredient Function

Main Ingredients Aloe Barbadensis Leaf Juice (Stabilized Moisturizing, soothing

Aloe Vera Gel), Water skin

Humectants Propylene Glycol, Sodium Hyaluronate, Retain moisture, keep

Sodium PCA skin soft and hydrated

Emulsifiers Stearic Acid, Glyceryl Stearate, PEG-100 Help oil and water
Stearate, Cetyl Alcohol phases mix, create a
stable emulsion

Emollients (Skin Prunus Armeniaca (Apricot) Kernel Oil, Softens skin, provides
Conditioning Oils) Simmondsia Chinensis (Jojoba) Seed Oil, lipids to maintain skin
Petrolatum, Lanolin, Lanolin Alcohol barrier
 Softening & Skin Stearyl Stearate, Ethylhexyl Palmitate, Improves skin texture,
Conditioning Ethylhexyl Stearate, Diethylhexyl makes skin smoother
Agents Adipate, Oleic Acid

Antioxidants Tocopherol (Vitamin E), Ascorbic Acid Protects skin from free
(Vitamin C) radicals, aids skin
recovery

Active Ingredients Soluble Collagen, Hydrolyzed Elastin, Hydrates, soothes, and

Chamomilla Recutita (Matricaria) Flower helps repair damaged
Extract, Allantoin skin

pH Adjuster Triethanolamine Balances the pH of the

product

Preservatives Diazolidinyl Urea, Methylparaben, Prevents bacterial and

Propylparaben fungal growth, extends
shelf life

Fragrance Fragrance (Parfum) Provides a pleasant

scent

3.2 Functions

1. Moisturizes and Hydrates the Skin​

Aloe Barbadensis Leaf Juice (Aloe Vera), Sodium Hyaluronate, Sodium PCA, Propylene
Glycol help retain moisture, keeping the skin soft and hydrated.​
Glycerin draws moisture from the environment, preventing dryness.

2. Soothes and Repairs the Skin​

Aloe Vera has soothing properties, effectively reducing irritation, sunburn, and mild
inflammation.​
Chamomilla Recutita (Matricaria) Flower Extract has anti-inflammatory effects, calming
sensitive skin.​
Allantoin supports skin healing and helps repair damaged skin faster.

3. Enhances Elasticity and Anti-Aging​

Soluble Collagen, Hydrolyzed Elastin improve skin elasticity and reduce the appearance of
wrinkles.​
Tocopherol (Vitamin E), Ascorbic Acid (Vitamin C) are powerful antioxidants that protect the
skin from environmental damage and premature aging.

4. Softens and Nourishes the Skin​

Prunus Armeniaca (Apricot) Kernel Oil, Simmondsia Chinensis (Jojoba) Seed
Oil,Petrolatum, Lanolin supply essential lipids, keeping the skin soft and preventing dryness .​
Oleic Acid, Stearyl Stearate help smooth the skin and improve texture.

5. Protects the Skin and Maintains the Natural Barrier​

Lanolin, Petrolatum create a protective layer on the skin surface, reducing water loss and
shielding the skin from environmental damage.

3.3 Preparations ( based on

https://www.ijnrd.org/papers/IJNRD2402060.pdf?fbclid=IwZXh0bgNhZW0CMTAAAR11FU3QYhIpNxMwkoJ3I575yf7qSEEvg--v
3K8jvdy5IgRRJHXeXnTooXw_aem_E4pIiJER_lInZ0anciTY3Q )

Step 1: Prepare the Aqueous Phase​

- Dissolve Stabilized Aloe Vera Gel in water, stirring gently. ​
- Add Propylene Glycol, Sodium Hyaluronate, Sodium PCA to the solution and continue
stirring until fully dissolved.

Step 2: Prepare the Oil Phase ​

- Heat Petrolatum, Lanolin, Apricot Kernel Oil, Jojoba Oil, Ethylhexyl Palmitate, Ethylhexyl
Stearate, Diethylhexyl Adipate, Oleic Acid to approximately 70-75°C. ​
- Add Stearic Acid, Glyceryl Stearate, PEG-100 Stearate, Cetyl Alcohol to the oil mixture
and stir until completely dissolved.

Step 3: Emulsification​
- Heat the aqueous phase to 70-75°C. ​
- Slowly add the oil phase into the aqueous phase, stirring continuously with a high-speed
mixer to form an emulsion. ​
- Maintain the temperature at approximately 70°C to ensure a stable emulsion.

Step 4: Add Active Ingredients ​

- When the mixture cools to below 50°C, add Soluble Collagen, Hydrolyzed Elastin,
Tocopherol, Chamomilla Recutita Flower Extract, Ascorbic Acid, Allantoin, and continue
stirring until evenly distributed. ​
- Adjust the pH by gradually adding Triethanolamine until the desired pH level (~5.5-6.5) is
achieved.

Step 5: Preservation and Finalization ​

- When the mixture cools to below 40°C, add Diazolidinyl Urea, Methylparaben,
Propylparaben as preservatives. ​
- Finally, add Fragrance (Parfum) and stir gently to blend the scent. ​
- Fill the product into bottles or jars and store at room temperature.

III. Some updated technologies in using Aloe vera

3.1) Aloe vera-Based Hydrogels for Wound Healing: Properties and

Therapeutic Effects
(Chelu, M., Musuc, A. M., Popa, M., & Calderon Moreno, J. (2023). Aloe vera-Based
Hydrogels for Wound Healing: Properties and Therapeutic Effects. Gels, 9(7), 539.
https://doi.org/10.3390/gels9070539.)

Biological and Pharmacological Effects of Aloe vera

Applications in Food Industry

Biological Activities: Antioxidant, antiviral, antibacterial, antifungal, antioch atoxigenic.
Uses: Healthy drinks, sports beverages, and functional foods.
Health Benefits:
Activates lipolysis; reduces obesity-related metabolic changes.
Lowers blood sugar (evidenced in mouse models).
Combats intestinal disorders (e.g., constipation, dysentery, hemorrhoids).

Applications in Medical Field

Metabolic Syndrome: Effects on dyslipidemia, hyperglycemia, hypertension, obesity.
Pharmacological Effects:
Anti-inflammatory, anti-diabetic, immunomodulatory, anticancer.
Hepato-protective, anti-ulcer, anti-arthritic, anti-rheumatic properties.

Dental Applications
Positive effects on oral health (e.g., healing avulsed teeth).
Polysaccharides like acemannan promote cell viability, DNA synthesis, and osteogenic gene
expressions.

Wound Healing Contributions

Reduces pain, combats inflammation, and moisturizes wounds.
Enhances collagen synthesis and epithelial cell migration.

Vitamin Absorption Enhancement

Increases absorption and prolongs plasma retention of vitamins C and E.
Aloe is considered a unique supplement for vitamin absorption.

Applications in Drug Delivery

Improves absorption of poorly absorbed oral drugs.
Acts as a stabilizing and enhancing agent.
Flexible platform for optimizing oral drug delivery.

Release Mechanisms in AV-Based Hydrogels

Diffusion-Controlled: Governed by concentration gradient and gel structure.
Swelling-Controlled: Swells upon absorbing water, releasing agents via expanded pores.
Degradation-Controlled: Hydrogel matrix degrades, gradually releasing agents.

Inflammatory and Healing Properties

Inhibitory: Anti-inflammatory and antimicrobial effects.
Stimulatory: Promotes wound healing, accelerates skin regeneration.

Therapeutic Applications
Oral and topical therapies: Wound healing, gingivitis, mucosal lesions, etc.
Uses in oral care products, menopausal treatments, and veterinary practice.

Reduction of Inflammation: Aloe Vera (AV) for Psoriasis

●​ Psoriasis Overview:
○​ Immune disease causing inflammation and itchy rashes; affects ~125 million
globally.
○​ Associated with comorbidities like arthritis, cardiometabolic disease, and
depression.

●​ Aloe Vera's Role:

○​ Effective in topical psoriasis treatment; reduces hyperkeratinization (61%
reduction in animal studies).
○​ Key bioactive compounds: Polysaccharides (glucomannan, acemannan), pectic
compounds, cellulose, hemicelluloses.

●​ Innovative Applications:
○​ Combined with Natural Rubber Latex for economic occlusive dressings.
○​ Dressings release 58.8% of AV over 4 days; exhibit high antioxidant and
phenolic compound retention.
○​ Proven biocompatibility and hemocompatibility in vitro.

Prevention of Bacterial Infection Using Aloe Vera (AV)

●​ Chitosan & AV Films: Encapsulated thymol (95.3% efficiency), effective against
bacterial pathogens (e.g., Bacillus, Staphylococcus, E. coli), with enhanced water
absorption and antioxidant activity.
●​ Polymer Composite Films: AV with polyvinyl alcohol demonstrated antimicrobial
activity (e.g., E. coli, P. aeruginosa) and potential for surgical wound infection
prevention.
●​ Alginate-Based Films: AV, honey, and cellulose nanocrystals showed excellent
antibacterial properties (e.g., Salmonella typhi, S. aureus) and mechanical stability for
dressings.
●​ Nanofiber Membranes: AV with chitosan or pullulan improved hydrophilicity, pore
size, and antibacterial activity against Streptococcus aureus, E. coli; recommended for
short-term wound dressing.
●​ Sustained-Release Hydrogels: Sodium alginate/polyvinyl alcohol enriched with AV
released active substances gradually (up to a week), promoted cell adhesion, and
demonstrated biocompatibility.
●​ Proven Antibacterial Agent: Effective against P. aeruginosa, Campylobacter rectus,
and E. coli, among others.

The skin is part of the body’s integumentary system and consists of the epidermis and dermis,
with a subcutaneous fatty layer, the hypodermis. It protects us against external factors and
prevents bacteria and germs from entering the body and blood and causing infections. At the
same time, the skin is vulnerable and can be affected by acute or chronic wounds. Wound
healing is a complex physiological process, which is achieved through four explicit phases:
hemostasis, inflammation, proliferation, and remodeling and involves the
epidermis-containing keratinocyte, melanocyte, and Langerhans cells, dermis, including
fibroblast, neutrophil, mast cell, and dermal dendritic cells, and the hypodermis, which
contains mesenchymal stem cells
Wound-Healing Process

●​ Phases: (i) Hemostasis (coagulation), (ii) Inflammation (up to 4 days), (iii)

Proliferation (3 days post-injury, overlaps with inflammation), (iv) Tissue Remodeling
(6 months–1 year, scar formation).
●​ Disruptive Factors: Infection, poor blood circulation, age, stress, diabetes, obesity,
smoking, diet, and trauma.
●​ Key Concern: Infection is the most common complication, emphasizing prevention.

Aloe Vera (AV)-Based Hydrogels

●​ Eco-Friendly Hydrogel: Natural ingredients (AV, SH, DA, CS, DES) showed
cytocompatibility, antibacterial effects (S. aureus, E. coli), and promoted skin
regeneration in mice within 12 days.
●​ Vaginal Tissue Repair: AV-alginate hydrogel with mesenchymal stem cells improved
smooth muscle, elastin, and decreased tissue stiffness in birth injury models,
suggesting potential for faster healing and prevention of pelvic organ prolapse.

Another study explored the potential for acute and chronic wound healing using piperine as a
new bioactive compound. New systems of bioactive hydrogels based on carbopol 934
containing piperine mixed with AV gels of different gel strengths were prepared and
characterized. The developed formulation system was investigated in an excisional wound
healing model in the rat model. The results of the in vivo study and histopathological
examination showed that the piperine-containing bioactive hydrogel system compared with
the piperine-free bioactive hydrogel system, leads to early and intrinsic wound healing.
Studying the influence of a commercial hydrogel formulation based on AV with
1,2-propanediol (propanediol) and triethanolamine (TEA) on skin wound healing was
investigated in female Wistar rats. Additionally, the study aimed to show that the presence of
specific additives, propanediol and triethanolamine, does not exert any negative effect on
wound healing. The results showed that the prepared hydrogel had a positive effect on
inflammation, angiogenesis, and wound contraction and reduced the total healing time by
29%, with the total closure of the wound being achieved in 15 days
Burn Treatment (Healing Burns)
Clinical Studies:
-​ 30 Patients with Second-Degree Burns:
. Comparison of AV cream and silver sulfadiazine.
. Healing time: AV (15.9 ± 2 days) < sulfadiazine (18.73 ± 2.65 days).
. No microbial contamination after 3, 7, and 13 days.
-​ 50 Patients with Second-Degree Burns:
. 98% unrefined AV gel from inner leaf.
. Early epithelialization, faster pain relief, cost-effective treatment.
-​ Double-Blind Trial on 111 Patients:
. Herbal AV cream + essential oils (Lavandula stoechas, Pelargonium roseum).
. More effective pain relief than sulfadiazine.
-​ Clinical Case Study:
. 17-year-old patient with rejected skin graft.
. Treated with AV gel for 21 days.
. Skin regeneration, no infection, no side effects.
Skin Protection During Chemoradiation
Multicenter Study:
-​ 120 Head and Neck Cancer Patients:
■​ AV gel vs. placebo.
■​ Skin toxicity assessed using RISRAS.
-​ Results:
■​ Reduced erythema (Week 5: 13.6% vs. 27.8%; Week 6: 24.1% vs.
42.6%).
■​ Reduced wet scaling and burning sensation.
-​ Conclusion:
■​ AV gel does not prevent radiation-induced dermatitis.
■​ Combining AV gel with skin care reduces symptoms.
Summary of Clinical Effects
-​ Maintains Skin Moisture and Integrity:
○​ Due to mucopolysaccharides, amino acids, zinc, and water.
-​ Cost-Effective and Efficient:
○​ Faster wound healing compared to alternatives.
-​ Mechanisms of Action:
○​ Increases epithelial cell viability, proliferation, and migration.
○​ Retains moisture, increases collagen, reduces inflammation.
○​ Inhibits pro-inflammatory cytokines, ROS, and JAK1-STAT1/3 signaling.
-​ Active Components:
○​ Acemannan, aloesin, aloe-emodin, aloin, emodin, glucomannan.
○​ Beta-sitosterol: Promotes angiogenesis.
Applications of AV Hydrogel Technology
-​ Drug Release Mechanisms:
○​ Diffusion, swelling, degradation.
-​ Interaction with Graphene Oxide (GO/rGO):
○​ Enhances antibacterial properties.
-​ Combination with Essential Oils and Herbs:
○​ Reduces pain and inflammation.
-​ Asymmetric Bilayer Membrane:
○​ Polycaprolactone (top layer), chitosan + AV (bottom layer).
○​ Potential use as wound dressings.

3.2 ) Efficacy of bacteriophages with Aloe vera extract in formulated

cosmetics to combat multidrug-resistant bacteria in skin diseases
(Maan, S. A., Faiesal, A. A., Gamar, G. M., & El Dougdoug, N. K. (2025). Efficacy of
bacteriophages with Aloe vera extract in formulated cosmetics to combat
multidrug-resistant bacteria in skin diseases. Scientific reports, 15(1), 4335.
https://doi.org/10.1038/s41598-025-86334-y)

1)​ Introduction:
-​ Skin infection is often related to Staphylococcus aureus (S. aureus) and Pseudomonas
aeruginosa (P. aeruginosa). They can develop several antimicrobial substances
→ The use of antibiotics is becoming less effective
→ An alternative method is using phage therapy as this has several benefits:
+​ Phages target only specific bacteria (without harming beneficial microbes).
+​ They evolve along with bacteria, potentially preventing resistance.
+​ They can be customized to treat specific bacterial infections.
-​ Aloe Vera has been proven to have many bioactive compounds that are related to
antimicrobial, anti-inflammatory, and wound-healing properties, which makes it
useful in treating skin infections.
→ Aim: Combination of Phage Therapy and Aloe Vera:
+​ Phages kill bacteria directly by infecting and lysing them.
+​ Aloe vera enhances the antibacterial effect and promotes wound healing.

2)​ Materials and Methods

a)​ Collection and extraction of Aloe vera leaves
b)​ Preparation of cosmetic gel: Aloe vera gel was prepared by mixing the following
ingredients: 8% stearic acid, 4% stearyl alcohol, 3% cetostearyl alcohol, 5% glycerin,
5% paraffin oil, 3% isopropyl myristate, 5% Tween 20, 0.5% active ingredient, 7%
perfume, and 1% methyl paraben. Aloe vera extract (0.1–0.5%) was mixed with a
gel-forming agent (carbopol).
c)​ Collection of clinical samples: Clinical samples were collected from patients with
skin infections.
d)​ Isolation and identification of pathogenic bacteria: The nutrient broth containing
clinical swabs was diluted in broth medium and inoculated onto cetrimide agar for P.
aeruginosa and Baird Parker media for S. aureus. The inoculated plates were
incubated at 37 °C for 48 h. Bacteria were identified using Gram staining and
VITEK2 system (which determines antibiotic resistance).
e)​ Isolation and identification of bacteriophages:
Phages were isolated from hospital sewage water, and the double agar overlay
technique was used to test phage activity against S. aureus and P. aeruginosa. Then,
Purified phages were stored at 4°C.
f)​ Biological Characterization of Phages: pH test, UV test, morphological test, and
Infectivity and Cross-infectivity.
g)​ Preparation of the Final Antibacterial Cosmetic Gel: A combination of cosmetic gel +
Aloe vera extract + phage cocktail was prepared.
h)​ Testing Antibacterial Activity:
 -​ Bacterial cultures (S. aureus and P. aeruginosa) were grown in a microplate.
-​ Three categories are tested: phages only, Cosmetic gel only, and Cosmetic gel with
phages (final product).
i)​ Testing Antibiofilm Activity:
-​ The bacteria (S. aureus and P. aeruginosa) were cultured in Tryptic Soy Broth (TSB).
-​ Apply Phages alone, Cosmetic gel alone, and Cosmetic gel with phages
-​ Plates were incubated at 37 °C for 24 h. After incubation, plates were washed three
times with 2.0 mL phosphate buffer (pH 7.2), fixed with 2% sodium acetate, and
stained with 0.1% crystal violet.
-​ Plates were cleaned with distilled water, dried, and the optical density of cell viability
and biofilm samples was measured at 620 nm and 570 nm, respectively, using an
ELISA reader.

3) Results​
3.1) Identification of Pathogenic Isolated Bacteria
-​ By gram staining and observing under a microscope, we obtain:
+​ P. aeruginosa:
●​ Gram-negative (stained pink).
●​ Straight rod-shaped cells.
+​ S. aureus:
●​ Gram-positive (stained purple).
●​ Cocci (spherical-shaped) arranged in clusters.
 -​ Antibiotic Resistance Testing (MIC Test) showed that both P. aeruginosa and S.
aureus were found to be multidrug-resistant (MDR), meaning they do not respond to
multiple antibiotics, making infections difficult to treat.
3.2) Isolation and characterization of phage
-​ Nine isolated phages were isolated with varied morphologies

3.3) Biological characters of isolated phages

Table 2
 -​ The S. aureus phages only affected S. aureus isolates
-​ The P. aeruginosa phages only affected P. aeruginosa isolates
-​ The phage cocktail (PC) was effective against all eight bacterial reference isolates.

Table 3
-​ Phages remained most stable at pH 7, with little reduction in activity at pH 6 and pH
8.
-​ The phage cocktail (PC) was resistant to all pHs, with the highest activities at pH 6, 7,
and 8.
Table 4
-​ The phage cocktail (PC) showed the highest resistance to UV exposure, especially at
45 cm distance.

3.4) Antibiofilm activity of formulated cosmetic gel F (CG + AVE + PC)

 -​ Viability test:
+​ Cosmetic gel (CG) alone had the weakest effect, reducing S. aureus by 18.27% and P.
aeruginosa by only 6.02%.
+​ Aloe vera extract (AVE) showed stronger antibacterial activity, reducing S. aureus by
76.69% and P. aeruginosa by 62.31%.
+​ The phage cocktail (PC) was highly effective, reducing S. aureus by 91.74% and P.
aeruginosa by 92.07%.
+​ The formulated combination (FCAP = CG + AVE + PC) was the most effective,
reducing bacterial viability by 97.11% for S. aureus and 93.77% for P. aeruginosa.

-​ Biofilm test:
+​ Cosmetic gel (CG) alone had the weakest antibiofilm activity, reducing biofilms by
18.93% for S. aureus and 24.48% for P. aeruginosa.
+​ Aloe vera extract (AVE) significantly reduced biofilm formation, showing a 79.65%
reduction for S. aureus and 72.90% for P. aeruginosa.
+​ Phage cocktail (PC) was even more effective, with 86.26% reduction for S. aureus
and 81.56% reduction for P. aeruginosa.
+​ The formulated combination (FCAP = CG + AVE + PC) had the strongest effect,
reducing biofilms by 88.90% for S. aureus and 87.46% for P. aeruginosa.

3.5) Longevity of formulated bacteriophages

-​ At room temperature:
FCAP (CG + AVE + PC) is the best formulation:
 +​ Maintains strong phage activity up to 60 days.
+​ Still detectable even at 90 days, though reduced.

-​ At 4°C (Refrigeration):
+​ Phages stored at 4°C survive longer than those at room temperature. At all categories,
the given data are higher than at room temperature.
+​ Especially in AVE + PC and the FCAP, the activities of phages live longer and are
stronger in 60 and 90 days.

4) Discussion
-​ P. aeruginosa and S. aureus isolated from wounds are known for antibiotic resistance,
making it difficult to treat infections using conventional methods.
-​ Aloe Vera has multiple bioactive compounds contributing to its antimicrobial
properties, such as Ascorbic acid, p-Coumaric acid, Pyrocatechol, and Cinnamic acid.
These compounds work through various mechanisms, including: Inhibiting bacterial
cell wall synthesis, blocking bacterial enzymes, disrupting biofilms, and reducing
oxidative stress.
-​ Many previous studies also reported that Aloe Vera have demonstrated activity
against various bacteria, fungi, viruses, and yeasts. Saponins and anthraquinones in
Aloe vera have been noted for their ability to disrupt bacterial membranes and inhibit
growth.
-​ Phagy therapy is more beneficial than the conventional anti-biotic methods. Phages
specifically target bacterial cells without harming human cells, making them a safe
and effective treatment option. The study isolated bacteriophages specific to S. aureus
and P. aeruginosa from infected wounds.
-​ The PC shows the highest resistance in pH and UV tolerance.
-​ Longevity and Stability of Bacteriophages: The formulated cosmetic gel (CG + AVE
+ PC) provided the highest stability, maintaining phage effectiveness for over 90 days
at 4°C.
+​ Reasons:
●​ Aloe vera contains antioxidants (such as ascorbic acid, coumaric acid, and
cinnamic acid), which prevent oxidative damage to the phages.
●​ Aloe vera acts as a stabilizing agent, forming a protective matrix around
phages, preventing rapid degradation.
●​ The cosmetic gel contains emulsifiers like stearic acid and carbomer, which
prevent phage aggregation or degradation over time.
-​ Effectiveness Against Biofilms:
+​ Biofilms provide a protective shield for bacteria, making infections more resistant to
treatment. P. aeruginosa and S. aureus form strong biofilms, which hinder antibiotic
penetration.
+​ This study showed that:
●​ The Aloe vera-infused cosmetic gel (CGAVE) and the phage cocktail (PC)
successfully inhibited biofilm formation.
 ●​ The combined formulation (CG + AVE + PC) was more effective than either Aloe
vera or phages alone.
●​ The gel + phages formulation prevented biofilm formation better than conventional
methods.
+​ Reasons: Aloe vera weakens biofilm structure, allowing phages to penetrate and
destroy bacteria, leading to a synergistic antibiofilm effect.

3.3 ) The efficiency of natural wound healing and bacterial biofilm

inhibition of Aloe vera and Sodium Chloride toothpaste preparation
(Vajrabhaya, L. O., Korsuwannawong, S., Ruangsawasdi, N., Phruksaniyom, C., &
Srichan, R. (2022). The efficiency of natural wound healing and bacterial biofilm
inhibition of Aloe vera and Sodium Chloride toothpaste preparation. BMC
complementary medicine and therapies, 22(1), 66.
https://doi.org/10.1186/s12906-022-03548-7 )

1)​ Introduction
-​ Aloe vera is known for its antimicrobial and wound-healing properties, which
promote fibroblast migration and reduce bacteria.
-​ Some previous studies showed that A. vera can reduce plaque accumulation
and improve oral health by its antibacterial and cell migration-promoting
effects.
→ Aim: Investigate whether an A. vera-based herbal toothpaste can inhibit P.
gingivalis planktonic and biofilm growth while supporting human gingival fibroblast
cell migration. → supports its clinical application.

2)​ Materials and Methods:

-​ Cell migration assay:
+​ The toothpaste used was Herbal Salt (Twin Lotus Co., Ltd, Bangkok,
Thailand), containing Aloe vera, Clinacanthus nutans, Orange Jessamine,
Hydrocotyl, Toothbrush Tree, Mangosteen, and Sodium Chloride.
+​ 200 mg of toothpaste was mixed with 1 ml Dulbecco's Modified Eagle Medium
(DMEM).
+​ Cell culture:
●​ Human gingival fibroblast cells were cultured in DMEM with 10% fetal calf
serum and antibiotics at 37°C with 5% CO₂ and 95% humidity.
●​ When the cells covered the dish fully, we used to detach them.
+​ Cytotoxic assay:
●​ Use to the toxicity of the toothpaste to the fibroblast cells.
●​ Cells were plated in 96-well plates at a density of 10,000 cells per well.
●​ The cells were incubated for 24 hours at 37°C to form a monolayer.
●​ The toothpaste solution was added in two concentrations: 0.02% and 0.2%.
●​ The cells were incubated for another 24 hours.
●​ Cell viability was measured using the MTT assay, which measures the ability
of living cells to convert MTT into formazan (a colored product).
●​ The experiment was repeated three times.
+​ Boyden chamber assay (Cell migration test):
●​ To determine whether the toothpaste promotes gingival fibroblast migration.
●​ Cells were seeded into transwell inserts at a concentration of 250,000 cells
per well in a serum-free medium.
●​ The lower chamber contained medium with 5% fetal bovine serum and 0.2%
(v/v) toothpaste.
●​ In the control group, no toothpaste was added.
●​ The cells were incubated for 16 hours at 37°C. After that, the media were
removed from each well.
●​ The cells were then fixed with methanol, stained with Giemsa stain, and
washed.
●​ The non-migrating cells on the top of the transwell were removed by wiping
with cotton.
●​ Images of the migrating cells on the bottom of the transwell were taken at 12
random positions using a microscope and the migrated cells were counted
using Image J version 2.0.
●​ The experiment was repeated five times.

-​ Antibacterial effect study:

+​ To evaluate the inhibitory effect of toothpaste in the growth of P. gingivalis, a
bacteria responsible for periodontitis.

+​ Preparation of Toothpaste Slurry:

●​ The toothpaste was mixed with sterile distilled water.
●​ The mixture was centrifuged.
●​ The supernatant was filtered, and the filtered solution was used for all
antibacterial tests.

+​ P. gingivalis Culture: The bacteria (P. gingivalis, ATCC33277) was grown on

anaerobe basal agar with 5% sheep blood at 37°C for 72 hours in an
anaerobic jar.

+​ Disk Diffusion Test (Zone of Inhibition):

●​ To determine the inhibitory effect of toothpaste.
●​ A bacterial suspension of 1–5 × 10⁵ CFU/ml was spread on blood agar plates.
●​ A 6-mm disk soaked with 20 µl toothpaste slurry was placed on the agar.
●​ Plates were incubated at 37°C for 72 hours in anaerobic conditions.
●​ The diameter of the inhibition zone (clear area where bacteria did not grow)
was measured.
 +​ Minimal Inhibitory Concentration (MIC) Test:
●​ Each well in a 96-well plate contained:
★​ 100 µl toothpaste dilution
★​ 100 µl bacterial suspension (1–5 × 10⁷ CFU/ml)
●​ Plates were incubated at 37°C for 72 hours.
●​ The lowest concentration that prevented visible bacterial growth was
recorded.

+​ Biofilm Formation Inhibition Test:

●​ Bacteria were incubated with toothpaste in a 96-well plate for 72 hours.
●​ Wells were stained with crystal violet, and biofilm formation was measured
using a microplate reader at 550 nm.

+​ Biofilm Susceptibility Test:

●​ To measure the effect of toothpaste on pre-formed biofilms.
●​ Wells were treated with:
★​ Toothpaste slurry
★​ 2.5% NaOCl (positive control)
★​ 0.12% chlorhexidine (positive control)
★​ Treatments lasted 2 minutes.
●​ Biofilms were stained with MTT assay, and absorbance was measured at 570
and 690 nm.

3)​ Results
3.1) Cytotoxicity assay

-​ Both concentrations were non-toxic, with 99.07% in 0.02% Toothpaste and

99.44% in 0.2% Toothpaste.
 -​ And they used 0.2% concentration for the cell migration assay.

3.2) Cell migration assay

-​ The results of the Boyden Chamber assay indicated that the number of
migrated cells after treatment with 0.2% toothpaste was 78.71 ± 13.45 cells.

-​ Here are the representative images of the cell migration assay.

3.3) Antibacterial effect

-​ Disk diffusion test​

+​ The zone of inhibition results (Fig. 4a) demonstrated that the 0.12%
chlorhexidine group had a mean diameter of 2.02 ± 0.05 cm, which was
significantly greater compared with the herbal toothpaste group (1.82 ± 0.02
cm) (Fig. 4b).

-​ Minimal inhibitory concentration (5a):

+​ We can see that herbal toothpaste inhibits growth at a lower dilution (160)
than chlorhexidine (320). → The herbal toothpaste slurries were less effective
in inhibiting planktonic P. gingivalis growth compared with 0.12%
chlorhexidine.

-​ Biofilm formation inhibition (5b and 5c):

+​ At 40-fold dilution, both herbal toothpaste and CHX strongly inhibited biofilm
formation (clear wells).
+​ As the dilution increased, biofilm growth gradually increased, meaning the
toothpaste and CHX became less effective at preventing biofilm formation.
+​ The herbal toothpaste (H) showed less biofilm formation compared to CHX at
640 to 5,120-fold dilutions.
+​ At 10,240-fold dilution, the herbal toothpaste still had a significantly higher
inhibitory effect compared to CHX (p < 0.05).
+​ At the highest dilution (20,480-fold), both substances had little effect, and
biofilms formed in both cases.
-​ Biofilm susceptibility test:

+​ We determined efficacy of the herbal toothpaste, 2.5% sodium hypochlorite,

and 0.12% chlorhexidine to kill P. gingivalis in the biofilm using the MTT
assay.
+​ 2.5% sodium hypochlorite treatment: 7.42 ± 5.52% of P. gingivalis was alive.
+​ Toothpaste treatment: 10.82 ± 5.52% of P. gingivalis was alive.
+​ 0.12% chlorhexidine: 38.22 + 9.13% of P. gingivalis was alive.

4)​ Discussion
-​ The present study evaluated the effect of an herbal toothpaste formulation on
in vitro human gingival fibroblast cell migration/wound healing and P.gingivalis
planktonic and biofilm growth.
-​ We found that the herbal toothpaste containing A.vera and Sodium Chloride
increased cell migration and inhibited P. gingivalis biofilm formation.
-​ Boyden Chamber Test:
+​ The results showed that the herbal toothpaste resulted in higher migrated
cells → meaning the herbal toothpaste enhanced cell migration → promoted
the wound healing effect → suggests that this toothpaste may help maintain
or improve gingival health during or after oral treatments.
-​ Disk Diffusion Test:
+​ 0.12% CHX produced a 20.2 mm inhibition zone and larger than that of herbal
toothpaste. The reason may be that the toothpaste has been diluted in a 1:3
ratio → decreasing its effectiveness.
-​ Broth Dilution Assay (MIC Test):
+​ The herbal toothpaste was less effective than 0.12% CHX at inhibiting P.
gingivalis in a liquid culture.
+​ However, this test is limited because it can only evaluate the planktonic
bacteria better than the one in the biofilm. → This result showed that the CHX
performed better with planktonic bacteria than the herbal toothpaste.
-​ Biofilm Inhibition Test Results:
+​ The results showed that the herbal toothpaste was better than 0.12% CHX at
preventing P. gingivalis biofilm formation and biofilm susceptibility.
+​ NaOCl is a substance that performed well in destroying biofilms. Our results
showed that it was more effective than CHX. However, NaOCl is toxic for oral
tissues, and the herbal toothpaste showed a higher effect than it.
→ Therbal toothpaste showed strong biofilm-killing ability, similar to NaOCl,
making it a promising alternative.

-​ Limitations of this study:​

+ The study was conducted only in the in vitro model → need more clinical
trials (in vivo tests) to prove its effect.
+ It only performs in one certain bacteria strain → additional tests are needed

5)​ Conclusion
-​ This in vitro study revealed that the herbal toothpaste containing A.vera
increased cell migration and inhibited P. gingivalis biofilm formation. An in vivo
study is necessary before this toothpaste can be widely used in patients.
VI. Discussion and Conclusion
Discussion

Aloe vera has been widely recognized for its beneficial properties in cosmetics and
skincare. Its popularity stems from its natural composition, which includes vitamins,
minerals, enzymes, amino acids, and polysaccharides. These components contribute
to its moisturizing, soothing, anti-inflammatory, and healing properties, making it a
versatile ingredient in cosmetic formulations.
Moisturizing Properties: Aloe vera is highly effective in hydrating the skin without
leaving a greasy residue. It penetrates deeply into the skin layers, making it suitable
for all skin types, including oily and acne-prone skin.
Soothing and Anti-inflammatory Effects: Aloe vera is known for its ability to calm
irritated skin, reduce redness, and alleviate conditions like sunburn, eczema, and
psoriasis. Its anti-inflammatory properties help in reducing swelling and discomfort.
Healing and Regenerative Properties: The plant promotes wound healing and skin
regeneration due to its ability to stimulate collagen production and improve skin
elasticity. This makes it a valuable ingredient in products aimed at reducing scars
and fine lines.
Antioxidant and Antimicrobial Effects: Aloe vera contains antioxidants that help
combat free radicals, reducing signs of aging. Its antimicrobial properties also make
it effective in treating acne and preventing infections.
Versatility in Formulations: Aloe vera can be incorporated into various cosmetic
products, including creams, lotions, gels, masks, and shampoos. Its compatibility
with other ingredients enhances its efficacy in multi-functional products.

Despite its numerous benefits, there are some considerations to keep in mind:
Purity and Concentration: The effectiveness of aloe vera in cosmetics depends on
the purity and concentration of the extract used. Products with low concentrations or
adulterated forms may not deliver the desired results.
Allergic Reactions: Although rare, some individuals may experience allergic
reactions to aloe vera. It is essential to perform a patch test before using new
products.
Regulation and Standardization: The cosmetic industry lacks stringent regulations
regarding the labeling and quality of aloe vera products, leading to variability in
product quality.

Conclusion
Aloe vera is a highly beneficial ingredient in cosmetics, offering a wide range of
advantages for skin health and appearance. Its natural composition and
multifunctional properties make it a popular choice for moisturizing, soothing,
healing, and protecting the skin. However, the quality and concentration of aloe vera
in cosmetic products are crucial for achieving the desired effects. Consumers should
be aware of potential allergic reactions and choose products from reputable brands
to ensure safety and efficacy. Overall, aloe vera remains a valuable and versatile
component in the cosmetic industry, contributing to the development of effective
and natural skincare solutions.