Isolation Of Nitrogen-Fixing Bacteria From Digestive Sludge Of Palm Oil Mill Waste On Ultisols Soil

Abstract

The anaerobic digestion of the biogas process results in Biogas Sludge palm oil liquid waste, which contains nitrogenfastening bacteria that can increase nitrogen nutrients in the soil.The purpose of this study is to determine the
characteristics and potential of nitrogen-fixing bacteria (NFB) in biogas sludge from anaerobic digestion of palm oil mill
effluent in increasing nitrogen nutrient availability in ultisol soil.These stages of research would include (1) isolating NFB
and obtaining morphological characteristics at Universitas Sumatera Utara Laboratory of Soil Biology, Faculty of
Agriculture, (2) ability assessment for the potential isolate of NFB in producing nitrogenase enzyme activity at the Soil
Research Institute, Bogor, West Java, (3) ability to provide nitrogen nutrients using the Complete Randomized Design (RAL)
within three replications. This research was observed for eight months in the field. Provide nitrogen nutrients using a
Complete Randomized Design (RAL) over three replications. This study was carried out in the area for eight months.The
analysis indicated that seven nitrogen-fixing bacteria isolates had flat elevations, smooth edges, white color, Gramnegatives, and coccus cell shapes. Isolate N3 has the highest nitrogenase enzyme activity of 2.2 nmol/hour compared to
other isolates and can increase the highest levels of ultisol soil nitrogen nutrients by 65% compared to controls. These
findings indicate that isolating NFB from biogas sludge can increase nitrogen nutrient availability in ultisol soils.