Judul: Analysis of Microbial Contamination in Sunblock Cream Containing Jackfruit Seeds Starch with Coconut Oil Emulsion
Abstrak: Tabir surya merupakan salah satu produk kosmetik yang sangat dibutuhkan sebagai bentuk pencegahan dampak negatif dari ultraviolet. Salah satu syarat krim tabir surya mendapat izin edar adalah nilai cemaran mikroba sesuai dengan standar keamanan Badan Pengawas Obat dan Makanan (BPOM). Pati biji nangka memiliki efek anti sinar ultraviolet karena mampu memantulkan sinar, serta minyak kelapa yang berperan sebagai antioksidan. Penelitian ini bertujuan menganalisis cemaran mikroba dalam krim tabir surya BNMK. Pengujian pada penelitian ini meliputi Angka Lempeng Total (ALT), kurva pertumbuhan bakteri, Angka Kapang Khamir (AKK), dan kurva pertumbuhan kapang khamir. Nilai ALT pada sampel sebesar 1.3 x 102 cfu/mL, sudah sesuai dengan standar BPOM (<103 cfu/mL). Kurva pertumbuhan bakteri menyatakan bahwa bakteri pada sampel diduga memiliki karakteristik yang sama dengan E. coli. Hasil uji AKK diperoleh koloni sebanyak 8 x 105 cfu/mL, lebih tinggi dari standar BPOM (<103 cfu/mL). Morfologi koloni menunjukkan bahwa yang terdapat pada sampel adalah khamir., Sunblock is one of cosmetic products that is needed as a prevention from the negative effects of ultraviolet. One of the requirements for sunblock cream to obtain a marketing authorization is the value of microbial contamination in accordance with the safety standards of Badan Pengawas Obat dan Makanan (BPOM). Jackfruit seeds starch has an anti ultraviolet effect because it can reflect light, and coconut oil acts as an antioxidant. This study aims to analyze the microbial contamination in sunblock cream Based on Jackfruit Seed Starch with Coconut Oil Emulsion (BNMK). Tests in this study include Total Plate Count (TPC), bacterial growth curve, Yeast Mold Count (YMC), and yeast mold growth curve. The TPC in the sample is 1.3 x 102 cfu/mL, in accordance with BPOM standards (<103 cfu/mL). The bacterial growth curve revealed that the bacteria in the sample were thought to have the same characteristics as E. coli. The YMC test results is 8 x 105 cfu/mL, higher than the BPOM standards (<103 cfu/mL). The colony morphology showed that the sample is yeast.
Keyword: jackfruit seed, microbial contamination, starch, sunscreen

Judul: Formulation and Effectiveness Test of Cream from  Shellfish Shells (Anadara antiquata Linn.) as Anti Acne Cream
Abstrak: Cangkang kerang bulu mengandung kitosan yang berpotensi sebagai antibakteri sehingga dapat dijadikan sebagai krim antijerawat. Penelitian ini bertujuan memperoleh sediaan krim dan menguji efektivitas kitosan dari limbah kerang bulu sebagai produk krim antijerawat. Derajat deasetilasi kitosan diukur menggunakan FTIR, kemudian serbuk kitosan ditambahkan pada krim antijerawat dengan variasi konsentrasi 5%, 10%, dan 15% (b/v). Uji fisikokimia, aktivitas antioksidan, dan aktivitas antibakteri menggunakan bakteri Propionibacterium acnes dan Staphylococcus epidermidis dilakukan terhadap ketiga variasi krim. Hasil penelitian menunjukkan bahwa derajat deasetilasi kitosan sebesar 97.49% dengan kadar air dan rendemen berturut-turut sebesar 3.49% dan 47.63%. Uji fisikokimia menunjukkan bahwa ketiga krim antijerawat memiliki pH 5, homogen, tipe krim O/W, dan memiliki daya sebar yang menurun seiring dengan meningkatnya konsentrasi serbuk kitosan. Simpulan dari penelitian ini yaitu krim dengan 15% serbuk kitosan memiliki aktivitas antioksidan terbaik dan krim 5% serbuk kitosan memiliki kemampuan krim terbaik dalam menghambat bakteri., Shellfish shells contain chitosan, which is potential as an antibacterial, therefore, it can be used as an anti-acne cream. This study aims to obtain cream preparations and test chitosan's effectiveness from shellfish waste as an anti-acne cream product. The degree of chitosan deacetylation was measured using FTIR, then chitosan powder was added to the anti-acne cream with various concentrations of 5%, 10%, and 15% (w/v). Physicochemical tests, antioxidant activity, and antibacterial activity using Propionibacterium acnes and Staphylococcus epidermidis bacteria were carried out on those various concentrations of the cream. The results of calculating the degree of deacetylation of chitosan based on FTIR spectra were 97.49% with water content and yield of 3.49% and 47.63%, respectively. The physicochemical test showed that the three anti-acne creams had a pH of 5, were homogeneous, type O/W cream, and had dispersion which decreased with the increasing concentration of chitosan powder. The conclusion of this research is that cream with 5% chitosan powder has the highest antioxidant activity and cream with 5% chitosan powder has the highest activity to inhibit bacteria.
Keyword: anti acne, antioxidant, chitosan, shellfish shells

Judul: Dynamics Model for Rural and Urban Economic Growth
Abstrak: Lewis theory of structural change has focused on mechanisms that allow countries to transform their domestic economic structure to a more modern economy. The proposed model deals with the mechanism of interaction between rural and urban Economic. This model is concerned with the process of labor transfer from rural to urban areas. This study aims to model the dynamics of economic growth in rural and urban areas, including determining the equilibrium solution and to carry out simulation of the model. The simulation results show that the transfer of labor from rural to urban areas will increase the rate of change of capital so that structural changes can be realized. In addition, increased propensity to save in rural areas will also accelerate structural change
Keyword: