Judul: Fingerprint, Antioxidant, and Anti-tyrosinase Activity of Fungus Comb Extract
Abstrak: Fungus comb merupakan suatu struktur yang dibuat oleh koloni rayap Macrotermitinae dengan banyak potensi karena mengandung metabolit sekunder seperti steroid, terpenoid, dan saponin, serta senyawa yang memiliki sifat antioksidan dan anti-tirosinase. Tujuan penelitian ini adalah menemukan pola sidik jari serta menentukan kapasitas antioksidan dan aktivitas anti-tirosinase ekstrak fungus comb. Kromatografi lapis tipis (KLT) digunakan untuk menggambarkan pola sidik jari. Pola KLT yang dihasilkan diolah dengan ImageJ dan diubah menjadi densitogram. Fungus comb diekstraksi dengan pelarut n-heksana dan etil asetat. Hasil KLT menunjukkan ekstrak mengandung steroid dan terpenoid serta memiliki sifat antioksidan. Kapasitas antioksidan diuji dengan pereaksi 2,2-difenil-1-pikrihidrazil. Ekstrak n-heksana memiliki nilai kapasitas antioksidan 9,07 mg asam askorbat ekuivalen (AAE)/g ekstrak sedangkan ekstrak etil asetat memiliki nilai 6,04 mg AAE/g ekstrak. Aktivitas anti-tirosinase diuji dengan substrat L-tirosina dan L-3,4-dihidroksifenilalanin (L-DOPA). Ekstrak n-heksana memiliki aktivitas anti-tirosinase lebih baik dengan nilai IC50 1804 µg/mL untuk L-tirosina dan 6784 µg/mL untuk L-DOPA., Fungus comb is a structure made by termite colony Macrotermitinae with lots of potential because it contains secondary metabolites such as steroids, terpenoids, and saponins and compounds containing antioxidant and anti-tyrosinase properties. This study aimed to determine fungus comb extracts' fingerprint pattern, antioxidant capacity, and anti-tyrosinase activity. Thin layer chromatography (TLC) was used to determine fingerprint patterns. The resulting TLC pattern was processed with ImageJ and converted into a densitogram. The fungus comb was extracted with n-hexane and ethyl acetate. TLC results showed that fungus comb extracts contain steroids and terpenoids and have antioxidant properties. The antioxidant capacity assay was carried out with 2,2-diphenyl-1-picrylhydrazyl reagent. N-hexane extract had an antioxidant capacity value of 9,07 mg ascorbic acid equivalent (AAE)/g extract, while ethyl acetate extract had 6,04 mg AAE/g extract. Anti-tyrosinase activity assay was carried out with L-tyrosine and L-3,4-dihydroxyphenylalanine (L-DOPA) as substrates. N-hexane extract had a better anti-tyrosinase activity with IC50 of 1804 µg/mL for L-tyrosine and 6784 µg/mL for L-DOPA.
Keyword: analisis sidik jari, antioksidan, anti-tirosinase, ImageJ, KLT

Judul: Potential Inhibition of Alpha-Glucosidase of Fungus Comb Extract from Macrotermitinae Subfamily
Abstrak: Subfamily Macotermitinae termite nests have a unique structure, namely fungus comb which contains bioactive compounds that can be used as antidiabetic and anticancer agents. The aim of this research was to determine the toxicity and bioactivity of α-glucosidase inhibition from fungus comb fractions and extracts. Toxicity of fungus comb extract was tested using the brine shrimp lethality test (BSLT) method. Fungus comb extract is classified as a toxic extract because it has an LC50 value of 656,75 ppm which the third fraction is the most active fraction with an LC50 value of 96,16 ppm. Antidiabetic bioactivity of fungus comb extract was tested using the inhibition of α-glucosidase activity to hydrolyze p-nitrophenylα-D-glucopyranoside. Fungus comb extract has an IC50 value of 979,58 ppm which the third fraction is the most active fraction with an IC50 value of 423,74 ppm. Fungus comb fractions and extract do not hace antidiabetic bioactivity as well as acarbose with an IC50 value of 0,24 ppm, Sarang rayap subfamili Macrotermitinae memiliki struktur yang unik yakni fungus comb yang mengandung senyawa-senyawa bioaktif yang dapat dimanfaatkan sebagai antidiabetes dan antikanker. Tujuan dari penelitian ini menentukan toksisitas dan bioaktivitas inhibisi enzim α-glukosidase dari fraksi dan ekstrak fungus comb. Toksisitas ekstrak dan fraksi fungus comb diuji dengan metode brine shrimp lethality test (BSLT). Ekstrak fungus comb tergolong sebagai ekstrak yang toksik karena memiliki nilai LC50 sebesar 656,75 ppm dengan fraksi ketiga sebagai fraksi teraktif dengan nilai LC50 sebesar 96,16 ppm. Bioaktivitas antidiabetes ekstrak fungus comb diuji dengan menggunakan metode inhibisi aktivitas enzim α-glukosidase untuk menghidrolisis p-nitrofenil-α-D glukopiranosida. Ekstrak fungus comb memiliki nilai IC50 sebesar 979,58 ppm dengan fraksi ketiga menjadi fraksi teraktif dengan nilai IC50 sebesar 423,74 ppm. Fraksi dan ekstrak fungus comb belum memiliki bioaktivitas antidiabetes sebaik akarbosa dengan nilai IC50 sebesar 0,24 ppm
Keyword: α-Glucosidase, Antidiabetic, Acarbose, Fungus Comb, Macrotermitinae

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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