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This paper mainly focuses on the isolation and screening of actinomycetes from the south coast of Yogyakarta, which has bioactivity against plant pathogenic fungi. Actinomycetes with bioactivity against Phytophthora palmivora, a plant pathogenic fungus that causes fruit rot disease, was isolated and screened. The medium used for the isolation was starch casein mixed with antifungal compound of nystatin (25 µg/mL) and cycloheximide (75 µg/mL). The samples were pretreated by heating them for 15 minutes at 65℃. Bioactivity assay of the plant pathogenic fungi was conducted using the disc diffusion agar method. From the experiment, 36 isolates were obtained from 30 sediment samples. Two isolates, RS001.05, and RS003.04 showed inhibitory activity against the growth of the cocoa plant pathogenic fungi Phythopthora palmivora. RS001.05, which showed higher activity, was selected to be identified using DNA molecular identification. Microbial identification and characterization showed that RS.001.05 was actinobacteria, part of the genus Streptomyces, and part of the Streptomyces sp. with a homology was 99%. The phylogenetic tree showed that RS001.005 isolate was part of the same group as Streptomyces indonesiensis and Streptomyces malaysiensis. [ABSTRACT FROM AUTHOR]

Acrylic acid (AA) monomer is an important chemical for the acrylic polymer industry. Wastewater discharged from manufacturing poly-acrylic acid contains a certain amount of unreacted AA, making the wastewater acidic. When discharged directly into sewage, this acidic wastewater exhibits a very high chemical oxygen demand (COD) value. Furthermore, due to the toxicity of AA to aquatic organisms, the AA-containing wastewater needed to be treated accordingly, complying with environmental standards before being discharged into the environment. We prepared two types of industrial wastewater containing AA from wastewater of a commercial poly-acrylic acid plant, and they were treated using coagulation, flocculation and adsorption methods on a laboratory scale with a maximum capacity of 50 L in batch mode. We scaled up the processes to treat industrial wastewater on a mini-pilot scale with a maximum capacity of 1,000 L in batch mode. The experimental results showed that the established mini-pilot scale waste treatment plant had produced an effective waste treatment by conducting coagulation, flocculation, and adsorption process for the removal of acrylic acid from the industrial wastewater, from 8,230 mg/L of COD value to less than 83 mg/L, with over 99.0% removal of AA from the industrial waste. [ABSTRACT FROM AUTHOR]