Judul: Degradasi Limbah Buah-buahan dan Sayur-sayuran pada Produksi Eko-enzim
Abstrak: Eco-enzyme is the product of the facultative anaerobic fermentation process of domestic agriculture waste which is carried out for several months and enriched by sugar and water addition. This research aims to study the degradation process during fermentation and to identify the characteristics of eco-enzyme. The ratio of the composition of the eco-enzyme solution consisting of organic kitchen waste (fruits or vegetables): sugar: water was 3:1:10, respectively. During the fermentation observation, characterization was tested by cellulase activity, pH, reducing sugar, total acid, alcohol, and microscopic surface morphology. The results showed that during week-0 to week-12th fermentation, there was the degradation of carbohydrates into reducing sugars, acids, and alcohol. Besides, cellulase activity also increased from 1.24U / mL to 2.2 U / mL in fruit waste in the range of week-3rd and week-6th. The increase in reducing sugars, total acid, and decrease in pH was very significant in the range of week-3rd and week-6th. From this research, it can be concluded that degradation of the substrate occurs during fermentation and the highest fermentation results occur in week-6 for fruit waste, which different results from vegetable waste., Eko-enzim adalah produk proses fermentasi anaerob dari limbah pertanian domestik yang dilakukan selama beberapa bulan dengan penambahan gula dan air. Tujuan dari penelitian ini adalah mengkaji proses degradasi selama fermentasi dan mengidentifikasi karakteristik eko-enzim. Perbandingan komposisi bahan untuk memproduksi eko-enzim terdiri dari limbah dapur organik (buah-buahan atau sayuran) : gula : air secara berturut-turut adalah 3:1: 10. Selama fermentasi dilakukan karakterisasi hasil terhadap aktivitas selulase, pH, gula pereduksi, total asam, alkohol, dan pengamatan morfologi permukaan. Hasil penelitian menunjukan bahwa selama fermentasi minggu ke-0 hingga ke-12 terjadi degradasi karbohidrat menjadi gula pereduksi, asam, dan alkohol. Disamping itu, aktivitas selulase juga meningkat yaitu dari 1,24U/mL menjadi 2,2 U/mL pada limbah buahbuahan di rentang minggu ke-3 dan ke-6. Peningkatan gula pereduksi, total asam, serta penurunan pH terjadi sangat nyata pada rentang minggu ke-3 dan ke-6. Dari penelitian ini dapat disimpulkan bahwa degradasi substrat terjadi selama fermentasi dan hasil fermentasi tertinggi terjadi pada minggu ke-6 untuk limbah buah-buahan, berbeda hasilnya dengan limbah dari sayur-sayuran.
Keyword: cellulase activity, eco-enzyme, fermentation, aktivitas selulase, fermentasi, eko-enzim

Judul: Analisis Karakteristik Kimia, Biologi dan Organoleptik Eco-enzyme Berbahan Baku Kulit: Nanas, Melon, Pepaya dan Pisang
Abstrak: Eco-enzyme merupakan larutan hasil fermentasi limbah organik. Dalam pembuatan eco-enzyme digunakan gula, limbah organik seperti kulit buah atau sayur, dan air dengan perbandingan masing-masing 1:3:10. Eco-enzyme dapat dimanfaatkan sebagai pupuk, pestisida, cairan pembersih rumah tangga, serta dapat digunakan untuk mengurangi pencemaran air dan udara. Penelitian ini bertujuan mengetahui karakteristik kimia, biologi dan organoleptik eco-enzyme berbahan baku kulit: nanas, melon, pepaya dan pisang pada jenis gula yang berbeda serta mengetahui potensi eco-enzyme sebagai pupuk organik cair. Hasil analisis kimia menunjukkan bahwa eco-enzyme memiliki pH di bawah 4,00 serta eco-enzyme mengandung N, P, K, dan C-Organik yang masih dibawah standar mutu pupuk organik cair. Eco-enzyme kulit pepaya memiliki kandungan N-Total dan P tertinggi dibanding perlakuan kulit buah lainnya. Eco-enzyme kulit pisang memiliki kandungan K dan C-Organik tertinggi dibanding perlakuan kulit buah lainnya. Kandungan N, P, K dan C-Organik perlakuan gula merah lebih tinggi dibanding perlakuan gula pasir. Hasil analisis karakteristik biologi eco-enzyme menunjukkan bahwa total mikrob dan fungi perlakuan gula merah lebih tinggi dibanding perlakuan gula pasir. Hasil uji organoleptik menunjukkan bahwa eco-enzyme memiliki aroma asam khas fermentasi dan memiliki warna kuning-kecoklatan hingga coklat., Eco-enzyme is a solution of organic waste fermentation. Eco-enzyme produced by sugar, organic waste such as fruit peels or vegetables, and water in a ratio of 1:3:10. Eco-enzymes can be used as fertilizer, natural pesticides, household cleaners, and can be used to reduce water and air pollution. This study aims to determine the chemical, biological, and organoleptic characteristics of eco-enzymes made from peels of: pineapple, melon, papaya and banana on different types of sugar and to determine the potential of eco-enzymes as an organic liquid fertilizer. The chemical analysis results showed that the eco-enzyme has a pH below 4.00 and the content of N, P, K and organic carbon in eco-enzyme are below the range of values in the quality standards of liquid organic fertilizer. Eco-enzyme from papaya peel has the highest N and P content compared to other fruit skin treatments. Eco-enzyme from banana peel has the highest K and organic carbon content compared to other fruit peel treatments. The content of N, P, K and organic carbon in the palm brown sugar treatment was higher than the white sugar treatment. The results of the analysis of the biological characteristics of the eco-enzyme showed that the total microbe and fungi treated with palm brown sugar were higher than white sugar. The results of the organoleptic test showed that the eco-enzyme has a sour fermented scent and a brownish-yellow to brown color.
Keyword: fermentation, nutrients, organic acid, total microbial population

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: