Cedarwood oil at .6% was the most effective sebum-reducer they tested.
Quote:
The volunteer was requested to make a note of application of face wash and face cream daily on the given diary sheets. Sebumeter readings were taken 3 weeks and 6 weeks later.
Cedar wood and elubiol application led to a significantly greater fall in the sebum reading at 6 weeks as compared to 3 weeks. Treatment with Poplar bud, on the other hand showed no difference between 3rd and 6th week. A comparison between the treatments indicated that at 3 weeks the average percentage reduction in sebumeter readings on forehead and cheek was best with cedarwood (p <0.01 better than elubiol). The effect of poplar bud was comparable to elubiol.
At 6 weeks the effects of cedarwood were consistently maintained. The effect of elubiol improved, while poplar bud remained the least effective although this was not a consistent effect as seen by the wide variation in response. EXAMPLE 35
In this example the sebum control properties of moisturizing gels with plant extracts, cedarwood extract and hydrolysed soy protein, at a lower concentration of 0.5% is demonstrated.
This study was a double-blind, randomised, single centre study comparing 2 test gels (containing hydrolysed soy protein and cedarwood extract) with placebo Test products: Columns=2 ProductActive MTCedarwood extract - 0.5% DEHydrolysed soy protein - 0.5% BOPlacebo. 40 female volunteers aged between 13 to 19 years and having a sebumeter reading of 180 mu g/cm <2> took part in the study. These volunteers were instructed to avoid any other face cream, face wash or any other cosmetics during the 12 weeks of the study. During the first 2 weeks of the study, volunteers were instructed to use the face wash twice a day for washing their face. This period was considered as the conditioning period.
A baseline sebumeter reading was taken at the end of the conditioning period on 4 sites i.e. left forehead, left cheek, right forehead, and right cheek. Tubes containing the test products (which were coded and randomly allocated to each site) were dispensed to the volunteers. Each volunteer was given two test gels, one for left side of the face and the other for right side of the face. The choice of gel for the specific side of the face was made by random allocation. The volunteers were instructed to apply the test gels twice a day after washing the face with the given face wash for the next 12 weeks. Both volunteer and the study coordinator were not aware of the treatment dispensed ensuring the double blind nature of the study.
Adverse events were recorded. Results:
The two test products significantly reduced sebum readings as compared to the placebo.
The average % reduction for each of the three gels is tabulated below: Id=Table 1 (a) - Columns=5 Title: % Reduction (forehead) Head Col 1 AL=L: Treatment Head Col 2 to 5: Time (weeks) SubHead Col 1: SubHead Col 2: 3 SubHead Col 3: 6 SubHead Col 4: 9 SubHead Col 5: 12 HSP16.8441.0961.1463.41 Placebo14.123.4129.9739.62 Id=Table 1 (b) - Columns=5 Title: % Reduction (forehead) Head Col 1 AL=L: Treatment Head Col 2 to 5:
Time (weeks) SubHead Col 1: SubHead Col 2: 3 SubHead Col 3: 6 SubHead Col 4: 9 SubHead Col 5: 12 HSP19.1735.9448.7956.23 Placebo11.8923.1935.0946.02
Id=Table 2 (a) - Columns=5 Title: % Reduction (forehead) Head Col 1 AL=L: Treatment Head Col 2 to 5: Time (weeks) SubHead Col 1: SubHead Col 2: 3 SubHead Col 3: 6 SubHead Col 4: 9 SubHead Col 5: 12 HSP19.1735.9448.7956.23 Placebo11.8923.1935.0946.02 Id=Table 2(b) - Columns=5 Title: % Reduction (cheek) Head Col 1 AL=L: Treatment Head Col 2 to 5:
Time (weeks) SubHead Col 1: SubHead Col 2: 3 SubHead Col 3: 6 SubHead Col 4: 9 SubHead Col 5: 12 HSP20.2847.0558.6868.11 Placebo17.9132.5743.5151.81
Id=Table 3(a) - Columns=5 Title: % Reduction (Forehead+ cheek) Head Col 1 AL=L: Treatment Head Col 2 to 5: Time (weeks) SubHead Col 1: SubHead Col 2: 3 SubHead Col 3: 6 SubHead Col 4: 9 SubHead Col 5: 12 cw18.2140.7659.762.45 Placebo13.1224.9933.442.45 Id=Table 3(b) - Columns=5 Title: % Reduction (Forehead+ cheek) Head Col 1 AL=L: Treatment Head Col 2 to 5:
Time (weeks) SubHead Col 1: SubHead Col 2: 3 SubHead Col 3: 6. SubHead Col 4: 9 SubHead Col 5: 12 HSP19.741.2353.561.88 Placebo14.827.7339.1648.82
Id=Table 4.: Columns=6 Title: Reduction in sebum levels for the three gels at the end of 12 weeks. Head Col 1: Product Head Col 2: 0-3 Head Col 3: 3-6 Head Col 4: 6-9 Head Col 5: 9-12 Head Col 6: 0-12 CW0.041 * 0.006 * 0.004 * 0.0660.00 * HSP0.011 * 0.0012 * 0.0059 * 0.027 * 0.00 * Placebo0.060.120.230.180.00 * *P < 0.05 - Significant EMI31.1 EMI31.2 EMI32.1 EMI32.2 EMI33.1 EMI33.2 EMI34.1 Conclusions:
- The two extracts- cedarwood and poplar bud extract retained their activity at 0.5%. and effectively reduced the sebum levels. 2) The two extracts performed at parity at the end of the study period. 3) Though the placebo also appeared to lower the sebum level the activity was significantly lower than the test gels. EXAMPLE 36
In this example the lipase inhibition activity of cedarwood extract and hydrolysed soy protein is demonstrated. The test was carried out on female volunteers within the age group of 13-18 years having a sebumetre reading of 180 ug/cm2.
A lipase inhibition kit from Sigma was used for the study. This kit consists of a substrate, trezma buffer, and indicator. Standard lipase was procured separately.
The reaction mixtures and blanks were prepared as listed below: Columns=6 Head Col 1: Reaction mix. Head Col 2: Substrate Head Col 3: Buffer Head Col 4: Lipase Head Col 5: water Head Col 6: Extract (inhibitor) Test Std.10ml1ml1ml2.5ml- Test Mix. .10ml1ml1ml2ml0.5ml Blank10ml1ml-3.5ml-
The solutions were pippetted out into the test tubes as mentioned above. The tubes were shaken vigorously for around 5 secs. and were kept in a constant temperature bath at 37 DEG C for 3 hours. After the incubation period contents of the test tubes were poured into titration flasks and 3ml of ethanol was pipetted into each flask. Six drops of thymol phenophthalein indicator was added. In a burette 0.05 N NaOH solution was taken and used for titration. Each flask was titrated to a deep blue color which lasted for about 30secs. The blank and the test mixtures needed to show the same blue color. The final reading was noted and the initial reading subtracted from the final. This is the amount of NaOH required to neutralise the fatty acids liberated due to lipase activity.
The activity was calculated as follows: 0.05N NaOH used for test mix.- 0.05N NaOH used for blank = 0.05N NaOH required to neutralise fatty acids liberated. Lipase activity = Amount of 0.05N NaOH. Results: The burette reading for the test mixtures and the blank are tabulated below: Columns=3 Head Col 1: Test Mixture Head Col 2: Burette reading Head Col 3: Lipase Activity (Test mix- Blank) Lipase22- Lipase+CW15.212.4 Lipase+HSP16.213.4 Blank2.8-
Different concentrations of the inhibitor from 0.2-1.0% were used to determine the optimum concentration. The results of these are as given below: Columns=2 Title: Cedarwood Head Col 1: Concentration (%) Head Col 2: Lipase Activity 0.219.66 0.419.52 0.617.84 0.819.5 120.18 Standard Lipase20.3 Columns=2 Title: Hydrolysed soy protein Head Col 1: Concentration (%) Head Col 2: Lipase Activity 0.219.8 0.418.3 0.621.0 0.821.2 1.021.1 Standard Lipase22
Conclusion: The two extracts demonstrated lipase inhibition. The optimum concentrations were 0.4% for Hydrolysed Soy Protein and 0.6% for cedarwood respectively. EMI37.1 EMI37.2 EMI37.3 Conclusion
Bryan,
Johnson and Johnson Pacific PTY was the assignee of this study.
I came up with the following three studies from my Study Stack — there may be others, too, on its lack of effect on sebaceous glands, but I originally found these with just a quick search (the first two are in humans, the last one is in hamsters):
