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Some of the methanotrophic bacteria and N2O reducing bacteria have been proven to be able to support the plant growth and increase the productivity of paddy. However effect of the methanotrophic and N2O reducing bacteria application as a biofertilizer to indigenous N2O reducing bacteria is still not well known yet. The aim of this study was to analyze the diversity of N2O reducing bacteria in lowland paddy soil based on a nosZ gene. Soil samples were taken from lowland paddy soils in Pelabuhan Ratu Sukabumi, West Java, Indonesia. There were two treatments for the paddy field soil, ie. biofertilizer-treated field 20% fertilizer (50 kg/ha) with the addition of biofertilizer and 100% fertilizer. PCR amplification of nosZ gene was successfully conducted using nosZF and nosZR primer pair. Denaturing Gradient Gel Electrophoresis (DGGE) process was conducted at 150 V for 5.5h. There were three differences nosZ bands were sequenced. The phylogenetic analysis showed that they were close to uncultured bacteria. Microbial diversity in the biofertilizer-treated field was higher than that of in the 100% fertilizer-treated field. The biofertilizer treatment has higher in microbial diversity than that of applied non-biofertilizer paddy fields. This research might have impact in the application of biofertilizers due to the emission of N2O as a green house gas from paddy fields farming activity. The biofertilizer has great potential application in sustainable environmental friendly agriculture systems.

Diabetes mellitus (DM) is a serious health problem in Indonesia. Type 2 diabetes is a metabolic disease which primarily caused by obesity-linked insulin resistance. There is a link between insulin resistance and bacterial populations in the gut. Therefore, the aims of this study was to analyze composition of bacteria belong to the phylum Firmicutes and Bacteroidetes in women with type 2 diabetes and non-diabetic persons as control. The study included five female adults type 2 diabetes patients and five healthy controls. The bacteria composition was analyzed for abundance by denaturing gradient gel electrophoresis (DGGE). Metagenomic analysis based on 16S rRNA gene was represented by 12 DGGE bands. The twelve respective bands showed the similarity ranging from 77 up to 98%. Diversity of microbial composition in women type 2 diabetes was represented by five DGGE bands are Bacteroides fragilis, Bacteroides vulgatus, uncultured Bacteroides sp. clone Lb4eF4, uncultured bacterium clone 16sms90-5g05, and uncultured bacterium clone Malaga 1F14. Four DGGE bands in women healthy controls are closely related to uncultured bacterium isolate DGGE gel band Eub42, uncultured bacterium isolate DGGE gel band K115, uncultured bacterium clone HFV04255, and Enterococcus sp. the finding shows bacterial species belong to the phylum Bacteroidetes was mostly found in women diabetic group, while those belong to the phylum Firmicutes was mostly found in healthy controls.

Endophytic actinobacteria from medicinal plant may play a significant role in producing bioactive compounds. The information regarding their diversity is an important. Rhododendron are traditionally used for treating human disorders. One of the selected Rhododendron used in this study was R. zoelleri from Papua origin, which has been conserved and grown in Cibodas Botanical Garden, West Java, Indonesia. The aim of this study was to assess the existence of endophytic actinobacteria from R. zoelleri based on a culture-dependent and their community structure based on a culture-independent approach. Culturable actinobacteria were isolated and cultured on HV medium. Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) targeting the metagenomic 16S rRNA was used to analyse the structure of the actinobacterial community. Six culturable endophytic actinobacteria (200 cfu/g fresh weight) from R. zoelleri were successfully isolated, three isolates from leaf, and the other isolates were obtained from stem. The six culturable isolates were RZP 1.3, RZP 1.1, RZP 2.2, RZPB 1.1, RZPB 7.1, RZPB 4.1. Based on their morphological characteristics, the endophytes have Streptomyces characters. The existence of Streptomyces spp. were also confirmed with molecular analysis based on 16S rRNA gene. The phylogenetic analysis based on 16S rRNA gene to the reference strains available in EzTaxon-e database showed that six isolates were closely related to S. djakartensis strains of NBRC 15409ᵀ(99.19%), S. tritolerans strains of DAS 165T(99.90%), S. coelicoflavus strains of NBRC 15399T(99.59). However, they showed differences in morphological characteristics as compared with the reference strains. The metagenomic analysis of the DGGE profile based on 16S rRNA gene showed the community structure of endophytic actinobacteria from R. zoelleri which was represented by 13 DGGE bands. The bands were closely related to Agromyces, Gordonia, Microbacterium, Micromonospora, Propionibacterium, Saccharomonospora, Streptomyces which have 93.18%-100% similarity. Based on the data, it showed diversity of endophytic actinobacteria from R. zoelleri which may be further assess for their novelty and bioprospecting.