Plastic waste can cause serious environmental problems. This can be overcome by various efforts; one of them is by replacing the use of conventional plastic with biodegradable plastic. Biodegradable plastic can be produced from tubers containing starch. The purpose of this study was to explain the suitability of two tuber species with typical protein quality and different starch structures. Starch was obtained from suweg tuber (Amorphophallus campanulatus) and ganyong (Canna edulis Ker). The material invested was obtained by dissolving 4 grams of each starch, each of which was dissolved with distilled water then added with various weight carrageenan. The tensile strength of biodegradable plastic was tested using tensile testing machines, biodegradation of soaked plastics using EM4 (Effective Microorganism) with reduced weight measurements, and Fourier Transform Infra-Red (FTIR) was used to identify the structure of compounds contained in biodegradable plastics. The tensile strength test results of biodegradable plastic from ganyong/canna tubers were 3.35 MPa with elongation of 13.51%, while the plastic from suweg tubers of 2.45 MPa with elongation was 13.68% on the addition of 5% carrageenan, respectively. Plastic degradation testing obtained plastic decomposition up to 100% in 37 days for ganyong and 34 days for suweg, respectively. It showed that the plastics was easily degraded. Identified by FTIR showed chemical structures of OH phenolic alcohols, C = O carbonyls, CO esters, NH amides and amines, and C≡C alkyne.

Strobilanthes cusia is a herbaceous shrub that is a source of blue dye, grows well above an altitude of 1000 m. This plant is very easy to breed, and for the purposes of making this plant dye, it can be harvested every 3 months. The use of strobilantes cusia leaves as natural dyes has been managed by UMK Shibiru in the Ngadirejo area, Temanggung. The results in the form of pasta have been marketed to various regions and even abroad. Some of the products are directly used to dye fabrics to serve the needs of batik in various regions. The raw materials in the form of leaves and twigs are macerated using water, within three days. The effectiveness of the process can still be improved by examining the factors that influence the effectiveness of the maceration process. In this study, it was studied how the effect of material size and time on the effectiveness of the maceration process. The results showed that the smaller the size of the material and the greater the time used, the results obtained will be better, which was indicated by the intensity of the color of the extract produced. By using a UV-Vish Spectrophotometer, two colors were detected in the extract solution, namely blue with a wavelength of 409 nm and red with a wavelength of 678 nm. However, from further observations by observing the absorbance, it can be seen that the red content is smaller than the blue color. The best result in this study was the maceration process using a leaf size of 0.5 cm and a maceration time of 3 days. Under these conditions, maceration results were obtained with an absorbance value of 24,295 for the blue color with a wavelength of 409 and an absorbance value of 12,150 nm for the red color with a wavelength of 678 nm.

Kekayaan alam berupa pohon kelapa yang tumbuh subur di Indonesia menajadi sesuatu yang terus menerus dikaji dan dikembangkan pemanfaatannya. Dari bagian  akar, batang, daun,  buah dan bunganya, dimanfaatkan dalam kehidupan manusia, namun masih terus dikaji untuk optimalisasi pemanfaatannya. Misalnya tempurung kelapa yang kadang dibiarkan menjadi sampah yang hanya dibakar, dapat dioptimalkan pemanfaatannya menjadi arang yang dibentuk menjadi briket. Hingga saat ini briket arang digunakan oleh masyarakat untuk keperluan rumah tangga, usaha maupun industri. Dibandingkan dengan bahan arang, briket lebih praktis dan lebih bersih sehingga lebih masyarakat lebih tertarik untuk menggunakannya. Dalam penelitian ini dipelajari pembuatan briket arang tempurung kelapa dengan tepung terigu sebagai perekatnya. Ukuran partikel arang serta konsentrasi perekat sangat mempengaruhi kualitas  briket yang dihasilkan. Penelitian ini akan mempelajari  pengaruh ukuran partikel arang dan konsentrasi perekat terhadap  sifat fisis dan laju pembakarannya. Penelitian dilakukan dengan menghaluskan arang dan mengayaknya untuk memperoleh serbuk arang dengan berbagai ukuran. Serbuk arang dicampur dengan perekat dengan berbagai konsentrasi,  kemudian dicetak, dan dioven. Dengan menggunakan perbandingan berat  arang dan volume perekat 1:1 diperoleh hasil yang cukup baik pada penggunaan ukuran partikel arang 40 mesh dan konsentrasi perekat 3%. Dengan kondisi tersebut diperoleh briket dengan kadar air 1,71%, kadar abu 1,5 % dan laju pembakaran 0,054 gram/menit.

Limbah kulit dan tonkol jagung banyak dijumpai setelah paska panen dan hanya dibuang oleh masyarakat, akan menyebabkan pencemaran lingkungan jika tidak ditangani. Limbah kulit dan tongkol jagung merupakan tanaman yang dapat digunakan sebagai bahan dasar pembuatan kertas seni, yang memiliki kandungan selulosa tinggi. Kertas seni dalam penelitian ini dibuat dari kulit jagung dan tongkol jagung. Penelitian ini dilakukan Laboratorium Proses Kimia Institut Sains & Teknologi Akprind Yogyakarta. Penelitian dilakukan dengan menggunakan variable konsentrasi NaOH dan waktu pemasakan. Proses pembuatan kertas seni diawali dengan pencucian, pemotongan, serta pengeringan kulit dan tongkol jagung. Pencucian berfungsi membersihkan kotoran yang menempel pada kulit dan tongkol jagung. Pemotongan berfungsi mempermudah proses pemasakan. Pengeringan berfungsi agar kandungan air dalam kulit dan tongkol jagung semakin rendah. Pemasakan dilakukan dengan menggunkan larutan NaOH konsentrasi yang ditentukan. Setelah itu dicuci, menggunakan aquadest sampai pH netral. Penggilingan pulp (blender) dengan penambahan lem PVAc dan garam (NaCl), kemudian dilakukan pencetakan dan pengeringan kertas dibawah sinar matahari. Setelah kertas kering kemudian dianalisis untuk mengetahui kuat sobek, kuat tarik dari kertas seni berbahan dasar kulit dan tongkol jagung dengan penambahan NaOH. Berdasarkan penelitian diperoleh kondisi proses yang terbaik dengan menggunakan konsentrasi NaOH 4% dan waktu pemasakan 80 menit. Dengan kondisi proses tersebut diperoleh kadar alfa selulosa 83,33%, kuat sobek 6,36 mN, dan kuat tarik 5,73 MPa.

In this research, waste of Aren fiber is utilized for raw material of composite. This aren fiber composite is used for insulator and sound absorber. The Aren composite is manufactured by pressing technique of mixture of aren, resin and hardener occur for 24 hours. The composites made from aren composite are tested in term of thermal conductivity and ability of sound absorber. The research aims to study an effect of resin to fiber ratio, size of Aren fiber to thermal conductivity, and sound absorber ability of aren composite material. The result shows that the optimum thermal conductivity of Aren composite is found to be 0, 3950 kcal/m h0C. This composite is obtained with resin-fiber ratio of 7:1, fiber length of 1 cm, 10% hardener, and pressure of 70 kg/mm2. Meanwhile, for optimum sound absorber composite is obtained with resin-fiber ratio of 6:1, fiber length of 2 cm, 10% hardener, and pressure of 70 kg/mm2. The composite has noice reduction of 40,1 dB and transmission loss of 46,1 at frequency of 500 Hz.