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Excessive production of melanin causes various dermatological disorders including hyperpigmentation. To search for anti-melanogenesis candidates from natural products, we discovered that leaves of Osmanthus fragrans var. aurantiacus (OFA) suppressed melanin production. The extract of OFA leaves and its fractions were subjected to bioactivity-guided separation by targeting active constituents and a total of four triterpenoids were obtained: 3α,24-dihydroxyurs-12-en-28 oic acid (1), pomolic acid (2), maslinic acid (3), and corosolic acid (4). Compounds 1 and 2 were isolated from this plant for the first time. All compounds were evaluated for their inhibitory activities against melanin production and tyrosinase activity. Active compounds were further investigated to understand their mechanisms of action. Results revealed that they significantly down-regulated TYRP-1 and TYRP-2 expression levels. Our results clarified the whitening property of this plant and provided evidence that active constituents of this plant possessed anti-melanogenesis effect and anti-tyrosinase activity for the first time.

English as a global language facilitates the people to communicate with each other despite different lingua-cultures or accent. Communication will be something important to build the socio condition of civilians in every single country. This background of research leads to get to know about English Language Teaching (ELT) to the people whose first language is not English. Each country in Asia or Europe whose English is not their first language has its differences in teaching and learning about English. The four basic things of English, such as reading, writing, and speaking will be the challenges that they need to be faced. According to the basics of four skills, speaking is the hardest one for most non-native speakers. Therefore, the teachers need to have particular ways to teach about speaking to increase students’ skill ability in EFL countries. This research is aimed to show the differences and comparisons among Indonesian and South Korea as the representatives of Asia, also Russia and Poland as the representatives of Europe whose first language is not English. This purpose means that people can distinguish among different types in each country for teaching and learning English, moreover for speaking skills.