Judul: Formulasi dan Uji Efektivitas Umbi Rumput Teki (Cyperus rotundus L.) dan Daun Patikan Kebo (Euphorbia hirta L.) sebagai Bahan Aktif Serum Wajah
Abstrak: Rumput teki dan patikan kebo merupakan tanaman gulma yang belum dimanfaatkan secara optimal padahal memiliki berbagai senyawa bioaktif bermanfaat. Penelitian ini bertujuan mendapatkan formula sediaan serum antijerawat dan pencerah berbahan dasar ekstrak umbi rumput teki dan daun patikan kebo. Tahapan penelitian terdiri atas ekstraksi, formulasi sediaan serum, uji fisikokimia, dan uji bioaktivitas. Umbi rumput teki dan daun patikan kebo dimaserasi sehingga menghasilkan rendemen sebesar 4.33% dan 11.41%. Formulasi sediaan serum menggunakan konsentrasi ekstrak umbi rumput teki yaitu 15% dan ekstrak daun patikan kebo sebesar 0.5% (F1), 0.8% (F2), dan 1.1% (F3). Seluruh sediaan serum memiliki pH yang berkisar 4.41-4.54, viskositas <20 cP, dan homogen. Hasil uji antibakteri terhadap Staphylococcus epidermidis tergolong sedang dan kuat (9.91-10.24 mm). Hasil uji antioksidan sediaan serum memiliki rentang nilai inhibisi sebesar 83.94%-84.20%. Hasil uji inhibisi tirosinase terbaik diperoleh pada F1 dengan nilai IC50 sebesar 107.33 μg/mL. Simpulan penelitian ini yaitu F1 merupakan sediaan serum terbaik., Cyperus rotundus and Euphorbia hirta are weed plants that have not been utilized optimally. The aim of this study was to obtain an antiacne and lightening serum formulation based on C. rotundus tuber extract and E. hirta leaves and its bioactivity analysis. The research steps consisted of extraction, serum formulation, physicochemical, and bioactivity test. C. rotundus tubers and E. hirta macerated with 96% ethanol solvent resulted 4.33% and 11.41% extract yields respectively. All of serum formulations used 15% concentration of C. rotundus tuber extract and E. hirta extract by 0.5% (F1), 0.8% (F2), and 1.1% (F3). All serum preparations had pH ranging from 4.41-4.54, viscosity <20 cP, and homogeneous. The results of the antibacterial test against Staphylococcus epidermidis were moderate and strong with a value range of 9.91-10.24 mm. The results of the antioxidant test of serum preparations have a range of inhibition values of 83.94%-84.20%. The best antityrosinase test results were obtained in the F1 formula with an IC50 value of 107.33 μg/mL. It was concluded that F1 was the best serum formulation formula.
Keyword: antibacterial, antioxidant, cosmetic, tyrosinase inhibition, weeds

Judul: Stabilitas Mutu dan Efektivitas Antibakteri Krim dan Sabun Cair Wajah Berbahan Aktif Tea Tree Oil dan Kolagen Ikan
Abstrak: Tea tree oil adalah bahan aktif yang mengandung terpinen-4-ol yang berguna untuk pengobatan jerawat dikarenakan memiliki aktivitas antibakteri. Penelitian ini bertujuan untuk mendapatkan komposisi formulasi krim dan sabun cair yang terbaik, stabilitas mutu produk, mengetahui efektivitas antibakteri, dan pendugaan umur simpan formulasi terbaik. Penelitian ini menggunakan persentase 0.5%, 1.25%, 1.5% tea tree oil dari sediaan krim, dan digunakan persentase 3%, 4%, 5% kolagen ikan serta 0.5%, 0.7%, 0.9% tea tree oil dari sediaan sabun cair. Pemilihan formulasi ditentukan dari segi parameter analisis produk dan organoleptik dengan menggunakan pembobotan termodifikasi dan aspek harga produksi ekonomis. Pada penelitian ini formulasi krim dengan persentase tea tree oil 1.5% (F3) serta formulasi sabun cair dengan persentase 3% kolagen ikan dan 0.5% tea tree oil (a.x) dipilih karena memiliki keunggulan dari segi parameter organoleptik dan analisis produk. Formulasi krim F3 memiliki nilai pH 7.26, viskositas 10360 cP, dan daya sebar 5.03 cm. Formulasi sabun cair a.x memiliki nilai pH 7.97 dan asam lemak bebas 0.59%. Umur simpan produk krim ditentukan oleh parameter kritis daya sebar, sedangkan untuk produk sabun ditentukan oleh parameter kritis asam lemak bebas. Produk krim dan sabun cair memiliki efektivitas antibakteri dikarenakan adanya diameter zona hambat. Kedua produk tersebut juga memperoleh persentase penerimaan umum yang cukup baik sehingga dapat diterima oleh konsumen dan mampu bersaing dengan produk komersial., Tea tree oil is an active ingredient that contains terpinen-4-ol which is useful for treating acne due to its antibacterial activity. This study aims to obtain the best formulations of cream and liquid soap, quality stability, antibacterial effectiveness, and estimate the shelf life of the best formulations. This study used percentages of 0.5%, 1.25%, 1.5% tea tree oil from cream preparations, and used percentages of 3%, 4%, 5% fish collagen and 0.5%, 0.7%, 0.9% tea tree oil from liquid soap preparations. The choice of formulation was determined in terms of product analysis and organoleptic parameters using modified weighting and economical aspects. In this study, cream formulations with a percentage of 1.5% tea tree oil (F3) and liquid soap formulations with a percentage of 3% fish collagen and 0.5% tea tree oil (a.x) were chosen because they have advantages in terms of organoleptic parameters and product analysis. The F3 cream formulation has pH value of 7.26, viscosity of 10360 cP, and spreadability of 5.03 cm. Liquid soap formulation a.x has pH value of 7.97 and a free fatty acid of 0.59%. The shelf life of cream products is determined by the critical parameter of spreadability, while for soap products is determined by the critical parameter of free fatty acids. Cream and liquid soap products have antibacterial effectiveness due to diameter of inhibition zone. Both products also obtained a fairly good percentage of general acceptance so that they can be accepted by consumers and are able to compete with commercial products.
Keyword: Efektivitas antibakteri, pendugaan umur simpan, stabilitas mutu, tea tree oil

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
Keyword: