Judul: Antioxidant Activity of Facial Serum Mixture from Apis cerana Calliandra Honey Fraction from Bandung, West Java
Abstrak: Madu banyak dimanfaatkan sebagai produk olahan pangan, kesehatan, bahkan kecantikan, karena dapat berperan sebagai antioksidan. Apis cerana merupakan salah satu lebah penghasil madu asli dari wilayah Asia. Penelitian ini bertujuan mengidentifikasi aktivitas antioksidan sediaan serum wajah dari fraksi madu kaliandra Apis cerana. Madu difraksinasi menggunakan perlarut air, n-heksana, dan etil asetat. Selanjutnya dilakukan analisis kadar total fenolik, flavonoid, aktivitas antioksidan 2,2-diphenyl-1,1-picrylhidrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), dan Ascorbic Acid Equivalent Antioxidant Capacity (AEAC). Fraksi etil asetat (FEA) merupakan fraksi terbaik dengan hasil pengukuran total fenolik dan flavonoid sebesar 5262,7 mg GAE/kg dan 1952,0 mg QE/kg, nilai IC50 DPPH sebesar 3,034 mg/mL, kapasitas antioksidan FRAP dan AEAC sebesar 3932,9 AAE/kg dan 3503,9 mg AEAC/kg. Sediaan serum diformulasikan menggunakan konsentrasi FEA 0,3% (F1) dan 0,6% (F2). Seluruh sediaan serum bersifat homogen, dengan daya sebar sebesar 6,5 cm dan rentang pH antara 5,8 – 6,8. F2 merupakan sediaan serum terbaik dengan nilai % inhibisi DPPH dan nilai absorbansi FRAP tertingi yakni sebesar 68,39% dan 0,110 pada 700 nm., Honey is widely utilized as a processed food, health, even beauty products, due to its antioxidant properties. Apis cerana is one of the native Asian bees that produce honey. This research aims to identify the antioxidant activity of facial serum mixture from calliandra honey fractions of Apis cerana. The honey was fractionated using water, n-hexane, and ethyl acetate solvents. Subsequent analyses included total phenolic content, flavonoid content, and antioxidant activity of DPPH, FRAP, and AEAC. Ethyl acetate fraction (FEA) proved to be the most potent fraction with total phenolic and flavonoid contents of 5262.7 mg GAE/kg and 1952.0 mg QE/kg, IC50 DPPH value of 3.034 mg/mL, also antioxidant capacity of FRAP 3932.9 AAE/kg and AEAC 3503.9 mg AEAC/kg. Serum mixtures were formulated using 0.3% (F1) and 0.6% (F2) concentrations of FEA. Both serum mixtures were homogeneous, with a spreadability of 6.5 cm and a pH range between 5.8 – 6.8. F2 was the best serum mixture with the highest DPPH inhibition percentage and FRAP absorbance values of 68.39% and 0.110 at 700 nm.
Keyword: antioxidant, fractionation, Apis cerana, calliandra honey, facial serum

Judul: Physicochemical Properties and Antioxidant Activities Multiflora Honey from Kerinci Regency Jambi
Abstrak: Madu merupakan cairan kental yang dihasilkan oleh lebah madu (Apis sp.) dari nektar bunga atau bagian tanaman lainnya. Penelitian ini bertujuan menganalisis sifat fisikokimia dan aktivitas antioksidan madu multiflora (madu hutan Apis dorsata) dan (madu budidaya Apis cerana) dari Kabupaten Kerinci, Jambi. Sifat fisikokimia yang dianalisis adalah warna, pH, viskositas, kadar air, kadar abu, kadar gula, kadar HMF, keasaman, dan aktivitas antioksidan. Hasil penelitian menunjukkan bahwa madu hutan berwarna Light Amber, sedangkan madu budidaya berwarna Extra Light Amber. Kualitas madu hutan yang memenuhi SNI 01-3545-2013 adalah pH, viskositas, kadar air, kadar gula, kadar HMF, dan keasaman, namun memiliki kadar abu yang melebihi batas SNI 01- 3545-2013. Madu budidaya memiliki pH, kadar gula, dan kadar HMF yang memenuhi SNI 01-3545-2013, namun memiliki viskositas, kadar air, kadar abu, dan keasaman yang belum memenuhi SNI 01-3545-2013. Madu hutan dan madu budidaya memiliki kapasitas antioksidan masing-masing sebesar 16,74 mgVCE/g dan 16,60 mgVCE/g, sedangkan aktivitas antioksidannya berturut-turut adalah 63,80% dan 63,28%, Honey is a thick liquid produced by honey bees (Apis sp.) from flower nectar or other parts of plants. This study aims to examine the physicochemical properties and antioxidant activities of multifloral honey (Apis dorsata forest honey) and (Apis cerana cultivated honey) from Kerinci, Jambi. The analysed physicochemical properties were colour, pH, viscosity, water content, ash content, sugar content, HMF content, acidity and antioxidant activity. The results showed that forest honey has Light Amber colour while cultivated honey has Extra Light Amber colour. The quality of forest honey that meet SNI 01-3545-2013 is pH, viscosity, water content, ash content, sugar content, HMF content, and acidity, however the ash content exceeded SNI 01-3545-2013. Cultivated honey has pH, sugar content, and HMF content is which meet the SNI 01-3545-2013, however the viscosity, water content, ash content, and acidity was that didn't meet SNI 01- 3545-2013. Forest honey and cultivated honey have antioxidant capacities of 16,74 mgVCE/g and 16,60 mgVCE/g, meanwhile the antioxidant activity were 63,80% and 63,28%.
Keyword: antioxidant activities, cultivated honey, forest honey, multifloral honey, physicochemical properties

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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