Judul: Literature Study of Traditional Use, Biological Activity, and Phytochemical Profile of Keji Beling (Strobilanthes crispus)
Abstrak: Masyarakat Indonesia banyak memilih pengobatan tradisonal dibandingkan pengobatan secara modern pada beberapa tahun terakhir. Hal ini karena efek samping obat-obatan modern cukup berbahaya dan harganya relatif mahal. Salah satu tanaman yang berpotensi sebagai obat herbal ialah keji beling (Strobilanthes crispus). Penelitian ini bertujuan mengumpulkan informasi terkait penggunaan tradisional, aktivitas biologis serta profil fitokimia, dan senyawa aktif ekstrak daun spesies tersebut berdasarkan telaah pustaka. Hasilnya menunjukkan ekstrak daun digunakan sebagai obat herbal, dikonsumsi dengan cara direbus atau diseduh sebagai teh kemudian diminum. Aktivitas biologisinya ialah antioksidan, antidiabetes, antikanker, antitumor, dan antibakteri. Golongan senyawa kimia yang terdapat dalam ekstraknya ialah flavonoid, alkaloid, saponin, tanin, dan terpenoid. Senyawa kimia yang dilaporkan memiliki aktivitas biologis antara lain asam silikat, polifenol, dan glikosida, serta dari golongan flavonoid seperti katekin, rutin, epikatekin, mirsetin, luteolin, apigenin, naringenin, dan kaempferol., Many Indonesian people have chosen traditional medicine over modern medicine in recent years. This is because the side effects of modern medicines are quite dangerous and the price is relatively expensive. One of the plants that have the potential as herbal medicine is keji beling (Strobilanthes crispus). This study aims to collect information related to traditional uses, biological activities as well as phytochemical profiles and active compounds of leaf extracts of these species based on a literature review. The results show that the leaf extract is used as herbal medicine, consumed by boiling or brewed as tea and then drink. Its biological activities are antioxidant, antidiabetic, anticancer, antitumor, and antibacterial. The chemical compounds contained in the extract are flavonoids, alkaloids, saponins, tannins, and terpenoids. Chemical compounds reported having biological activity include silicic acid, polyphenols, and glycosides, as well as from the flavonoid group such as catechins, rutin, epicatechin, myrcetin, luteolin, apigenin, naringenin, and kaempferol.
Keyword: aktivitas biologis, fitokimia, Strobilanthes crispus

Judul: Profile Metabolite and Antioxidant Capacity of Kejibeling Leaf Extract (Strobilanthes crispa (L.) Blume) Based on Different Extractor Solvents
Abstrak: Kejibeling (Strobilanthes crispa (L.) Blume) merupakan salah satu tanaman yang berpotensi sebagai antioksidan karena metabolit di dalamnya. Penelitian ini bertujuan mengidentifikasi metabolit ekstrak etanol 99%, etanol 50%, dan akuades menggunakan liquid chromatography-high resolution mass spectrometry (LC-HRMS), serta menentukan kapasitas antioksidan dengan metode cupric ion reducing antioxidant capacity (CUPRAC) berdasarkan perbedaan pelarut pengekstraksi pada ekstrak daun kejibeling. Total sebanyak 44 metabolit berhasil teridentifikasi pada ekstrak daun kejibeling, dengan masing-masing ekstrak etanol 99%, etanol 50%, dan akuades teridentifikasi sebanyak 34, 30, dan 18 metabolit. Ekstrak tiap pelarut berhasil terbedakan pada principal component analysis (PCA) dengan total PC1 dan PC2 sebesar 99%. Kapasitas antioksidan pada ekstrak etanol 99%, etanol 50%, dan akuades sebesar 3,47; 1,57; dan 0,69 mmol trolox ekuivalen/gram ekstrak (mmol TE/g ekstrak). Analisis partial least square (PLS) menunjukkan adanya korelasi antara metabolit yang terdeteksi dengan kapasitas antioksidan. Penelitian ini menunjukan senyawa yang teridentifikasi paling banyak dan kapasitas antioksidan paling tinggi pada etanol 99% dibandingkan pelarut lain., Kejibeling (Strobilanthes crispa (L.) Blume) is one of the plants that possesses antioxidant potensial by virtue of its metabolites. This study aims to identify metabolites of ethanol 99%, ethanol 50%, and aquades extracts using liquid chromatography-high resolution mass spectrometry (LC-HRMS), and to determine antioxidant capacity by cupric ion reducing antioxidant capacity method (CUPRAC) based on difference extraction solvents in kejibeling leaf extracts. A total of 44 metabolites were identified in kejibeling leaf extracts, ethanol 99%, ethanol 50%, and aquades extracts were identified 34, 30, and 18 metabolites. The extract of each solvent was successfully distinguished in the principal component analysis (PCA) with a total of PC1 and PC2 of 99%. The antioxidant capacity of ethanol 99%, ethanol 50%, and aquades extracts were 3.47, 1.57, and 0.69 mmoles of trolox equivalent/gram extract (mmol TE/g extract). Partial least square (PLS) analysis showed a correlation between detected metabolites and antioxidant capacity. This study showed the most identified compund and the highest antioxidant capacity in ethanol 99% compared to other solvents.
Keyword: antioxidant capacity, kejibeling, LC-HRMS, metabolites

Judul: Approximation of the Median of Poisson Distribution Using the Relation of Poisson-Gamma Distribution
Abstrak: A major drawback of median is that median cannot usually be defined in closed form, even in the cases where their distribution functions are known. This study gives an approximation of the closed form for the median of the Poisson distribution by using the relation of Poisson-Gamma distribution. The approximation uses elementary techniques based on the monotonicity of certain sequences involving tail probabilities of the Poisson distribution and the Central Limit Theorem. Furthermore, a closed form expression for the mean absolute deviation 􀜧|􀜰􀰒 􀵆 􀜯􀝁􀝀􁈺􀜰􀰒􁈻| is also studied. The median is relevant because of the fact that it minimizes the mean absolute deviation of a Poisson random variable (􀜰􀰒􁈻 by considering median as central tendency.
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