Original Measurement Method of Efficacy of Antianruff Cosmetics and Development of the New Active Commercial Proct õ1 Tetsuo Sakamoto õ2, Tetsuo Tsunoda õ2, Masaaki Uemura õ2, Kenzi Torii õ2, Hiromi Takehara õ3, Masairo Matsuoka õ2, K uninobu Okazaki õ3, Kenn-ichi Tomita õ2 and Muneo Tanaka õ2 Shiseido Co., Ltd. Research Center. õ2 Shiseido Co., Ltd. Scientific Division. õ2 This work was initiated to determine the quantity of dandruff scales by measuring total nitrogen content which can be recalculated based on the amount of proteins. And the method involved the collection of dandruff with a newly designed system and rinsing the dandruff from the scalp. Using this method, we investigated the seasonal variations in dandruff during a 13 month period on 160 subjects under strict control. We also studied the turnover time of the stratum corneum of the scalp and found that it averaged 15.3 days for the dandruff sub jects but 17.1 days for non-dandruff subjects. The newly synthesized vitamin E derivative, L-ascorbic acid dl-ƒ -tocopherol phosphoric acid ester potassium salt (EPC) was proven to have moisturizing effects, free fatty acid formation-inhibiting activity, and an antioxidant property but no bactericidal activity. In addition, EPC normalized the turnover time of the scalp in 16 subjects who used the hair tonic containing EPC. We conducted a double-masked application study of our new antidan druff hair tonic containing EPC. The antidandruff effects of our product were statistically significant when compared with a placebo. Its antidandruff effect was superior to that of zinc pyrithione shampoo.
Fig.- 1 Sunction system for dandruff collection J. Soc. Cosmet. Chem. Japan. Vol. 27, No. 3 1993
Table- 1 Test sample for the measurement 1) Control of the antioxidant effect 2) 2.4mM (0.2%) EPC 3) 2.4mM Vitamin E 4) 2.4mM Vitamin C 5) 24.mM Vitamin C+2.4mM Vitamin E (75% agueons solution of ethanol) Table- 2 Pityrosporum ovale culture medium Table- 3 Formulation of samples for double-masked application study Deionized water to 100%
Table- 4 Protocol for fhe double-masked application study Table- 5 Schedule of the collection week of dandruff J. Soc. Cosmet. Chem. Japan. Vol. 27, No. 3 1993 3 9 7
: Significant at 1% level Fig.- 2 Seasonal variation in dandruff generation Parakeratotic Index: parakeratotic cells /100 stratum corneum cells Spring (from March to May) Summer (from June to August) Autumn (from September to Novenber) Winter (from December to February) Fig.- 3 Individual subject's, seasonal variation in dandruff generation r=0.77 p<0.001 Fig.-4 Relationship between amounts of dandruff and parakerato tic index
NS: Not significant *: Significant at 5% level Fig.-18 Normalizining effect on the turnover time of EPC Table- Statistical evaluation of data dandruff (mg)/day/subject, Mean }SD *: P<0.05 **: P<0.01 ***: P<0.001 NS: Not Significant Table-9. Time-series analysis dandruff (mg)/day/subject, Mean }SD *: Significant at 0.5% level, NS: Not Significant
Table-10. Formulation of samples for application study
Table-11 Formulation of samples for application study 1. Hair tonic Fig.-21 Antidandruff effect of EPC and vitamin E+vitamin C 2. Shampoo Fig.-22 Antidandruff effect of EPC tonic and zinc pyrithione shamqoo
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