Patent Application
20070196507
Policosanol is a natural mixture of higher aliphatic primary alcohols (C24-C36) isolated from sugarcane wax and beeswax. It contains 1-Octacosanol, Triacontanol, Tetracosanol, Hexacosanol, Heptacosanol. These C24 to C36 primary alcohols are also found in sugarcane wax, ricebran wax, beeswax and various vegetable wax.
The structures of these primary alkanols are shown below.
Evaluation of Policosanol on Sebum Levels in Human Volunteers
Study Methodology and Administration
Sixteen healthy males of between 18 and 25 years of age were included in the study after they had signed the informed consent form. The main inclusion criterion was those with oily skin (scores >4 on a 0-5 scale). All the subjects were required to abstain from taking drugs, applying cosmetic products to their skin and exposing themselves to sunlight or any other source of ultraviolet radiation throughout the duration of the study.
2% or 5% Policosanol colloidal solution in 1,2 hexanediol was applied (0.2 ml) for seven days, twice daily, on the forehead. One side of forehead being treatment and the other side being the control (1,2 hexanediol treatment).
The efficacy was evaluated based on self-assessment and on the assessment of a panel of five independent cosmetologists, visually, using Sebutape (CuDerm Corp., Dallas, Tex.).
The sebutape is made of microporous, hydrophobic polymeric film composed of many tiny air cavities. The surface of the film is coated with a lipid porous adhesive layer that enables the tape to adhere to the skin surface. The tape is applied to the skin test site for optimal period of 1 hr. Sebum is absorbed into the tape, displacing the air in the microcavities. As this occurs, the lipid-filled cavities become transparent to light. Through this process, the sebum output from each follicle forms a sharply defined clear spot, its size roughly corresponding to the sebum volume.
When the sebutape are placed on the black background of the score card, the sebum on the tape becomes clearly visible as black spots. These spots are scored by a panel of cosmetologists on a scale of 0-5. These are pooled and from the mean of the scores, the percentage change is calculated from the control treatment site.
The safety and adverse events like erythema, burning sensation, itching, urticaria, edema, dermatitis, ochronosis, dryness of skin and any other non specific reactions, if any, were monitored.
The Policosanol colloidal solution was applied twice a day on one side of the forehead area for seven days. Pre-cleansing with soap/water was done before applications. The following observations were made
2% and 5% Policosanol colloidal solution was found to be safe for local application. It did not show any significant side effects and is safe for use on skin
Topical application of the Policosanol colloidal solution was found to decrease the sebum secretion in a concentration dependent manner. The 2% Policosanol solution reduced the sebum levels by about 11%, while 5% solution reduced sebum secretion by 27%.
Both the self-assessment and the assessment by the panel of cosmetologist revealed that 100% of the subjects showed marked decrease in sebum release.
The colloidal solution was found to be effective in people with moderately high oily skin (scores >3.5).
Additionally, one surprising observation was that Policosanol treatment protected the 1,2 Hexanediol induced dryness of skin and made the skin smooth and soft.
Anti-microbial Study against Propionibacterium acnes
To carry out the antibacterial activity of the products against Pr. acnes, the organism was first cultured in the anaerobic environment for which the anaerobic chamber was used. To standardize the growth of anaerobic culture of Pr. acnes in the anaerobic chamber, different culture media were used.
The anaerobic chamber [Model 8301-230, 3 ft polymer] used in the study was purchased from COY LABORATORY, USA which is provided with an automatic Air lock purge system.
The anaerobic condition in the chamber was maintained by initialization with N2 gas and then the mixture of gases of N2+H2+CO2 in the proportion 80+10+10. Two gas tank arrangement was made wherein only N2 was connected to the transfer chamber and mixed gas to the main chamber using Gassing Manifold (Hrishi Biotech, Pune, India)
Preparation of Anaerobic Media
The anaerobic media were prepared by heating the media while passing the mixture of gases of N2 and CO2 in 4:1 proportion simultaneously. The media were added with a redox indicator [resazurin: 0.001%] which is colorless in the presence of anaerobiasis and shows blue color in its absence. It was dispensed to 30/20/10 ml vials and sealed with rubbers and aluminum clamps and sterilized by autoclaving at 121° C. for minutes
Antimicrobial Study
Preparation of the inoculum The culture used in the study is Propionibacterium acnes ATCC 11827. The culture from the broth was inoculated to the fresh medium in vials (10%) and incubated for 48 hours at 37° C. The optical density (OD) of the culture at 625 nm was measured. It was maintained between 0.64 and 0.80 which contains approximately 12×106 cells/ml [4.0 MC Farland standard]
Procedure
Medium used for this study was reinforced clostridial agar (RCA). The medium that was prepared and sterilized in 30-ml vials was poured into the plates inside the chamber and allowed to solidify.
The culture was inoculated [0.3 ml/plate] into the plates and spread. After 30 minutes, antibacterial sterile discs [6 mm] were dispensed (2/plate). 2.5, 5.0, 7.5 and 10 μl of the prepared samples and controls were dispensed onto the discs. The plates were incubated inside the anaerobic chamber at 37° C. for 48 hours duration.
Policosanol in different concentrations (0.1-2%) prepared in 1,2 Hexanediol was used as vehicle for the study with 1,2 Hexanediol as control. Clindac A (Clindamycin Phosphate Gel 1% w/w) was used as positive control. The clearance zone formed around the discs were measured and expressed in mm. The results of the study are given below
As seen in the results above, Policosanol is effectively inhibiting Propionibacterium acnes in concentrations above 1% and the activity is comparable with Clindamycin gel. Inhibition of anaerobic organisms coupled with decrease in sebum secretion complements to its use in cosmetic formulations to control acne, as anti-seborrhea and antimicrobial, additionally could provide moisturizing properties. Policosanol could be used alone or in combination with other antibacterial, blemish erasers, sunscreen boosters amongst others.
Cosmetic Formulations based on Policosanol are described in the following examples.
This application is a divisional application of U.S. patent application Ser. No. 10/604,203 titled “Commercially viable process for high purity of fatty alcohol C24 to C36 and its cosmetic application for skin hair and nails” filed on Jul. 1, 2003.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10604203 | Jul 2003 | US |
| Child | 11696187 | Apr 2007 | US |
