Silkworms, Bombyx mori L., have been traditionally used as an oriental medicine to manage diverse pathological conditions including dermatological problems in East Asia, in addition to the use of their cocoons for making fabrics. The “mature” silkworms of B. mori have recently been regarded as a potential health supplement due to gaining their edibility for humans by a newly-developed steaming method. Therefore, the present study was conducted to investigate the effects of a larval powder of steamed mature silkworms (SMSP) on skin pigmentation and melanogenesis. Orally administered SMSP of pistachio cocoon strain significantly and reduced abnormal pigmentation caused by ultraviolet B on the murine dorsal skin. SMSP also showed a potential anti-melanogenic efficacy in modulating UVB-induced melanogenesis.

Royal jelly (RJ) is one of the most attractive functional foods that have been a commercial product, especially in dietetics and cosmetics in many countries. However, RJ has been evoked with dermatitis, acute asthma and anaphylaxis because of major RJ proteins. Therefore, to access water soluble royal jelly (WSRJ) that removed allergy-induced proteins as an effective whitening agent for cosmetics and potential external treatment for topical use, we investigated its ability to inhibit melanin biosynthesis. B16F1 cells were treated with 10 nM α-melanocyte-stimulating hormone (α -MSH) for 48hr, and then were treated with various doses of WSRJ for 36hr. WSRJ (1-10ug/ml) inhibited direct tyrosinase activity and cellular tyrosinase activity, which lead to the decrease of melanin synthesis in α-MSH stimulated B16F1 melanoma cells. In addition, we examined RT-PCR and Western blotting for melanogenesis-related genes such as tyrosinase, tyrosinase related protein 1 (TRP-1) and 2. WSRJ suppressed mRNA and protein expression of tyrosinase, tyrosinase related protein (TRP)-1 and TRP-2 in α-MSH stimulated B16F1 cells, and similar to positive control, arbutin. Our findings suggest that WSRJ induced the downregulation of melanogenesis by inhibiting tyrosinase, TRP-1 and 2 activations. It may serve as a new candidate in the new skin-whitening agents.

Background : Stevia rebaudiana (Asteraceae), a perennial plant, has been used as a low caloric sweetener and therapeutic agent for diabetes, hypertension, myocardial, and antimicrobial infections. It has been commonly used leaves and stems because of their high anti-oxidative potential. The present research was carried out to explore anti-oxidative and anti-melanogenic effects of aqueous extract of Stevia rebaudiana Bertoni flos in B16F10 cells. Methods and Results : Anti-oxidant activity of Stevia flos extract (SFE) was determined by using 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assay, nitric oxide (NO) radical scavenging method, and reducing power method. The results showed that the total phenolic content of SFE was 63.154 ± 0.0002 ㎍·QE/100㎎ and the total flavonoid was 8.64 1 ± 0.002 ㎍·GAE/100㎎. SFE exhibited a big significant effect on NO radical scavenging activity (IC50: 179.6 ㎍/㎖) comparing with standard ascorbic acid (IC50: 368.6 ㎍/㎖), and showed concentration dependent DPPH radical scavenging activity (IC50: 131.8 ㎍/㎖). Anti-melanogenic effect of SFE was also examined with B16F10 melanocytes. The amount of melanin synthesis followed by α-melanocyte stimulating hormone on B16F10 cells were significantly reduced in the presence of SFE treatment (p < 0.05). SFE also suppressed the tyrosinase activity (p < 0.05) and α-glucosidase activity (p < 0.05). Conclusion : These results provide evidence Stevia rebaudiana flos has an antioxidant potency and can be used as an anti-melanogenic agent.

히솝(Hyssopus officinalis)은 통화식물목 꿀풀과의 여러해살이풀로 방부제, 기침, 거담제 등 일반적으 로 방향족 허브와 약용식물로 사용되어왔다. 본 연구에서는 항산화 및 미백소재의 개발을 위해 히솝을 열수와 주정으로 추출하여 각 추출물의 in vitro 상에서의 항산화 효과 및 B16F10 melanoma 세포에서 멜라닌 생성 저해효과를 평가하였다. DPPH와 ABTS assay 시험법을 이용하여 항산화 효과를 측정한 결과, 히솝 추출물의 항산화 활성이 모두 농도 의존적으로 증가하였다. 또한 히솝 추출물은 tyrosianse 활성을 저해시켰으며, B16F10 세포에서 UVB로 증가된 활성산소와 α-MSH로 유도된 멜라닌 또한 감소시키는 효과를 보였다. 멜라 닌 생합성에 관여하는 유전자의 발현에 미치는 영향을 알아보기 위해 RT-PCR을 실시한 결과 히솝 추출물에 의해 MITF, tyrosinase, TRP-2의 발현이 감소되는 것을 확인할 수 있었다. 이러한 결과에 따라 히솝 추출물은 미백개선을 위한 화장품 소재로서 이용 가능성이 높을 것으로 사료된다.

Eruca sativa (known as rocket plant) is a member of the Brassicaceae, which is considered an important chemo-preventive plant family. Although Eruca sativa has positive biological effects such as antioxidant and renal protective activities, the effect of the Eruca sativa extract as a therapeutic agent for skin whitening has not been reported. In this study, we investigated the applicability of the extract of Eruca sativa as a functional materials by examining the its physiological activities. The Eruca sativa extract showed low cytotoxicity against murine melanoma B16F10 cells. At concentrations (below 100 mg/L) that showed none or little cytotoxicity, the Eruca sativa extract showed high DPPH radical scavenging activity (ID50, 17.60 mg/L). In addition, the Eruca sativa extract inhibited tyrosinase activity (ID50, 132.54 mg/L) and decreased melanin content (ID50, 158.90 mg/L). Finally, the treatment with the Eruca sativa extract suppressed the protein expression of tyrosinase in a concentration-dependent manner. These findings suggested that the Eruca sativa extract inhibited melanin synthesis by not only suppressing intracellular tyrosinase expression but also directly inhibiting tyrosinase activity. Therefore, these results indicate that the Eruca sativa extract may be an effective material for functional cosmetics such as skin whitening materials.