PREPARATION AND EVALUATION OF CREAM MASK 451 30 min for full skin acclimation to room temperature. The forearm of the volunteer was applied test cream mask with the dose of 10 mg/cm2 for 2 h. Two hours after application of the cream, we placed the skin detector lead on a test area of approximately 6 cm2 on the fore- arm. All data were obtained on the same day from each individual, and the average values of fi ve measurements per site were used in subsequent calculations. The moisture level of the treated skin was expressed as increased hydration (%) compared with untreated skin. To determine the clinical effi cacy of cream mask treatment, we studied three female vol- unteers (with the age range of 30–40), without current or prior skin disease. Subjects applied the cream mask to the full face every 2 d for 1 week. Part of face images were taken before and after cream mask treatment by using a KONG, Skin & Hair analysis System (Bomtech, Electronics, Co., LTD, Seoul, Korea). Statistical analyses. All experiments were performed at least three times independently. Differences between groups were calculated using a Student’s t-test. Results were deemed statistically signifi cant at p 0.05 and p 0.01. RESULTS BIOCHEMICAL COMPOSITION The wide variety of the biochemical compositions in seaweeds provides excellent bioac- tive components for cosmetic product development. To select potential seaweed species for ingredients of cosmetic production, we screened 10 seaweed species which are C. len- tillifera, U. lactuca, U. reticulata, S. oligocystum, S. crassifolium, S. denticarpum, K. alvarezii, K. striatum (Payaka), G. tenuistipitata, and G. bailiniae based on their biochemical compo- sitions including protein, lipid, polysaccharides, total chlorophyll, and carotenoid, as well as vitamin contents. The parameters of these seaweed species are presented in Table I. Proteins are considered useful ingredients for creating a suitable environment for healthy skin because they are able to bind water with the horny layer of skin and its annexes (24). The protein content in the 10 screened seaweed species ranged from 7.16% to 17.50% DW, with the highest value in U. reticulata (17.50% DW) and the lowest value in G. bailiniae (7.16%). Ten seaweed species possessed lipid content from 0.28% to 2.45% DW. Among them, the highest numbers of lipid content were observed in brown seaweed (ranged 1.32–2.45% DW), followed by green seaweed (0.95–1.95% DW), and the lowest numbers of lipid content were observed in red seaweed (0.28–1.3% DW). Some articles reported that among the group of steroids, phytosterols form an important group which may have particular biological activities such as anti-infl ammatory and antioxidative effects (25). It is widely recognized that moisturization is the fi rst step in acting against aging of the skin helping to maintain its appearance and elasticity, while also strengthening its role as barrier to harmful environmental factor (26). Polysaccharides play an essential role in cosmetic formulations as humectants and moisturizers. These compounds have a high capacity for water storage and can be linked to keratin through hydrogen bonds. Thus, they improve skin moisturization (1,27). Table I presented that total polysaccharides con- tent exhibited the highest value in K. alvarezii (53.08% DW) and the lowest value in G. bailiniae (43.78% DW). Further analysis of the main polysaccharide compositions is as follows: in green species, C. lentillifera, U. lactuca, and U. reticulata presented mainly ulvan,

Table I Biochemical Composition of 10 Seaweed Species in Vietnam Samples Protein (% of DW) Lipid (% of DW) Polysaccharide (% of DW) Carotenoid (μg/g of FW) Total chlorophyll (μg/g of FW) Vitamin content (μg/g of FW) A E C Caulerpa lentillifera 11.70 ± 1.15 0.95 ± 0.05 44.10 ± 0.52 86.20 ± 13.17 790.12 ± 50.21 2.87 ± 0.06 19.8 ± 0.06 140.75 ± 2.01 Ulva lactuca 16.79 ± 2.50 1.28 ± 0.07 47.20 ± 0.42 58.50 ± 4.97 551.41 ± 37.12 Nd 0.21 ± 0.02 142.96 ± 1.49 U. reticulata 17.50 ± 1.22 1.95 ± 0.12 49.70 ± 1.02 63.50 ± 6.32 653.27 ± 20.35 Nd 0.40 ± 0.01 150.12 ± 2.03 Sargassum oligocystum 10.45 ± 1.15 1.90 ± 0.12 50.14 ± 1.05 25.61 ± 5.23 251.36 ± 30.41 0.97 ± 0.31 2.54 ± 0.05 90.28 ± 2.19 S. crassifolium 12.57 ± 1.17 2.45 ± 0.72 52.30 ± 1.15 30.24 ± 2.75 281.86 ± 20.63 1.64 ± 0.07 4.50 ± 0.01 102.52 ± 1.17 S. denticarpum 10.50 ± 1.15 1.32 ± 0.35 49.87 ± 1.14 20.43 ± 1.42 215.12 ± 30.25 1.02 ± 0.13 0.23 ± 0.05 95.52 ± 1.46 Kappaphycus alvarezii 10.69 ± 1.11 0.85 ± 0.05 53.08 ± 1.97 37.63 ± 4.08 205.35 ± 29.85 1.23 ± 0.03 2.70 ± 0.02 85.68 ± 1.12 K. striatum 8.15 ± 1.16 0.28 ± 0.04 49.90 ± 2.53 26.52 ± 3.04 175.89 ± 24.02 0.56 ± 0.03 2.04 ± 0.07 80.23 ± 2.42 Gracilaria tenuistipitata 8.50 ± 1.20 1.30 ± 0.12 45.80 ± 1.75 22.61 ± 2.98 130.63 ± 15.11 1.97 ± 0.41 1.13 ± 0.02 82.45 ± 1.63 Gracilariopsis bailiniae 7.16 ± 1.10 1.17 ± 0.08 43.78 ± 1.50 19.20 ± 2.26 117.19 ± 10.38 1.45 ± 0.08 0.97 ± 0.01 74.17 ± 1.21 Nd: not detected. JOURNAL OF COSMETIC SCIENCE 452