Aims: The aims of this study were to screen for cellulose degradation activity from actinomycetes using agar plate method, detect β-glucosidase activity, morphology and molecular taxonomy study. Methodology and results: Preliminary screening for cellulose degrading Actinomycete was done on the carboxymethyl cellulose agar (CMC agar) and detected by flooding with gram iodine. It was found that 190 isolates were cellulase producing actinomycetes. Actinomycete isolate CDF2L1D13 showed maximum clear zone around the colony and the highest hydrolysis capacity value was 3.93. β-glucosidase activity was examined by measuring the amount of paranitrophenol (pNP) librated by Tako method. Study on comparison of the enzyme activity in CMC broth with alternative broth was performed. The highest β-glucosidase activity was found on alternative production medium that supplemented rice bran as a carbon source. β-glucosidase activity was 0.401 U/mL. The optimum pH of alternative production medium for producing β-glucosidase was at pH value 7 and incubated at 30 °C. Isolate CDF2L1D13 was antagonistic actinomycete against rice blast pathogen (Pyricularia oryzae). The character of this isolate was showed white color of substrate mycelium, white color of aerial mycelium, gray spore and spiral spore chain. Actinomycete isolate CDF2L1D13 was phylogenetically similar to Streptomyces osmaniensis. Conclusion, significance and impact of study: The result from this study indicated that Streptomyces osmaniensis has the potential on β-glucosidase production and it is antagonistic actinomycete against Pyricularia oryzae.
Actinobacteria

Aims: The diversity of the actinomycete community associated with Neofibularia sp. from Bira Island, Indonesia, has been largely unstudied. This study was undertaken to address the paucity of information in this respect. Methodology and results: Culturable actinomycetes 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 actinomycete community. Five culturable actinomycetes that were isolated belonged to the genus Streptomyces. They showed various degrees of similarity to the reference strains Streptomyces sampsonii (97- 99%), Streptomyces resistomycificus (97-99%), Streptomyces gougerotii (97-99%), Streptomyces erringtonii (97-99%), and Streptomyces albus (97-99%). The culturable actinomycetes isolates also showed differences in morphological characteristics as compared with the reference strains. The metagenomic analysis suggested that the actinomycete community was dominated by rare actinomycetes. Eight DGGE DNA bands that were obtained had sequences that showed similarities to Ferrithrix thermotolerans (88-94%), Lamia majanohamensis (87-92%), Aciditerrimonas ferrireducens (87-92%), and Thermobispora bispora (85-92%), while 4 bands had sequences similar to Propionibacterium acnes (97-100%) and another band matched sequences belonging to an uncultured bacterium clone (86-87%). The actinomycetes detected by the metagenomic approach were assigned identities that were mostly under 97.5% as compared with reference strains available in Genbank. Conclusion, significance and impact of study: Observations from both culture and DGGE analysis give a better understanding of the diversity and community structure of actinomycetes associated with Neofibularia sp. The culturable actinomycetes were Streptomyces spp., while rare actinomycetes were dominant when the metagenomic approach was adopted. Several of these actinomycetes showed identities below 97% when matched to reference strains, indicating possible novel species associated with the sponge Neofibularia.
Actinobacteria

Aims: Mangroves of Tanjung Lumpur, Kuantan, Pahang is considered as a relatively underexplored resource of actinomycetes. Based on the above perspective, a study was conducted on mangrove sediments of Tanjung Lumpur, Kuantan to isolate potential actinomycetes using several pretreatments and various selective media. Methodology and results: Sediments from five different sites at Tanjung Lumpur mangrove were collected and selectively pre-treated. The pretreated sediments were diluted and plated onto eight different selective media. A total of 172 potential actinomycetes were isolated from all the media. Antimicrobial activities of 61 selected strains were checked against 8 test microorganisms using cross streak method. Pretreatment of wet heat with seawater was the most effective method for the isolation of actinomycetes as it yielded a maximum of 105 actinomycete isolates and IM7 was the most suitable medium for actinomycete isolation with highest percentage of recovery (31 %). Forty three isolates (70.5 %) showed antimicrobial activities against one or more test microorganisms. Isolates IIUM B21 and IIUM B31 showed antimicrobial activity against all test microorganisms. Seven isolates showed antifungal activity as they inhibited only C. albicans. Ten isolates were randomly selected for identification based on partial sequences of 16S rRNA gene. Six isolates were found belong to the genus Streptomyces, two isolates belong to the genus Micromonospora and two isolates were identified as Rhodococcus spp. Conclusion, significance and impact of study: These findings revealed the potential of mangrove sediment of Tanjung Lumpur as an important source of actinomycetes with biosynthetic capabilities which might be beneficial to pharmaceutical industries.
Rhizophoraceae ; Actinobacteria

A new alpha-pyrone derivative, violapyrone J (1), and along with the two known violapyrones B (2) and C (3) were isolated from the fermentation broth of a marine actinomycete Streptomyces sp. SC0718. The structure of violapyrone J (1) was elucidated from 1D and 2D NMR spectroscopic analyses.
Actinobacteria* ; Fermentation ; Streptomyces*

Aims: The present study is aimed at taxonomic characterization and isolation of active compound MS01 from Streptomyces sp. FACC-A032 which exhibited strong antitrypanosomal activity (IC50 0.02 μg/mL). Methodology and results: Isolate FACC-A032 was characterized based on its cultural, morphological, physiological and genomic properties. Isolate FACC-A032 was tentatively identified as Streptomyces sp. Biochemical analysis of diaminopimelic acid (DAP) isomer of whole-cell hydrolysates further confirmed the isolate FACC-A032 that contained LL-DAP isomer as species belonging to the genus Streptomyces. The inoculum for submerged cultures of isolate FACCA032 was prepared from cultures on ISP2 agar. After eight days of growth at 28  2 °C and 200 rpm in fermentation medium M3, fermentation broth was extracted with butanol and the crude extracts (solvent layer) were separated and dried in vacuo. Further studies were carried out to isolate the active compound from the culture extracts of isolate FACCA032. Using bioassay-guided isolation, crude extract was partitioned based on different polarity. After which, the resulting elutes were tested for antitrypanosomal activity. The active fraction was analyzed with HPLC-DAD analysis. Based on the analysis, major peak in the active fraction was collected using HPLC preparative. Active compound MS01 was isolated and structure elucidated using NMR spectroscopy. Conclusion, significance and impact of study: Bioassay-guided isolation techniques used in this study had discovered an active antitrypanosomal compound, staurosporine, from Streptomyces sp. FACC-A032. This is the first discovery of staurosporine, a protein kinase inhibitor, from Malaysian soil actinobacteria Streptomyces sp. Therefore, the study demonstrated the potential of Malaysian soil actinobacteria as antitrypanosomal therapeutic agent.
Biological Assay ; Actinobacteria

Aims: The objective of this study was to analyze the genome of endophytic actinomycete associated with orchids and evaluate its plant hormone activities, including phytohormone, siderophore, ammonia production, zinc and phosphate solubilization. Methodology and results: Strain DR1-2 isolated from the roots of the Thai orchid, Dendrobium christyanum Rchb.f., was closely related to Pseudonocardia alni DSM 44104T, P. antarctica DSM 44749T and P. carboxydivorans Y8T (99.93-100% similarity) based 16S rRNA gene sequence. This strain exhibited IAA production (294.10 ± 12.17 μg/mL), phosphate solubilization (2.20 ± 0.08 solubilization Index, SI), positive for siderophore production and ammonia production (36.99 ± 2.24 μg/mL). It showed a maximum IAA of 489.73 ± 8.90 μg/mL, when optimized using 0.5% Ltryptophan, pH 6 and incubated at 30 °C for 7 days. The IAA of strain enhanced the root length, shoot length, number of roots and fresh weight of rice seedlings (Oryza sativa L. cv. RD49). The draft genome of strain DR1-2 was 6,077,423 bp in 23 contigs with G+C content of 74.6%. The average nucleotide identity-Blast (ANIb) and average nucleotide identity-MUMmer (ANIm) values of strain DR1-2 and related type strains were 95.81 to 97.25% and the digital DNA-DNA hybridization (dDDH) values were 72.60 to 74.00%, respectively. Genomic analysis of strain DR1-2 revealed that the gene encodes the enzyme involved in the phytohormones biosynthesis and gene clusters involved in the biosynthesis of bioactive metabolites. Conclusion, significance and impact of study Endophytic actinomycete, Pseudonocardia strain DR1-2 from Thai orchid, D. christyanum Rchb.f., exhibited significant IAA production and affected the growth of the plant, which was the potential source of plant hormones for agricultural applications.
Endophytes ; Actinobacteria ; Pseudonocardia

Aims: The marine actinomycetes are a rich source of novel bioactive molecules. Especially the exotic tropical marine habitat of the Kerala coastal region favours the actinomycete diversity. The present study focuses on the isolation, purification and morphological characterization of marine actinomycetes for the discovery of new bioactive compounds. Methodology and results: A total of 280 morphologically distinct actinomycetes were isolated from marine soil and sediments of 10 different isolation sites located along the coastal region of Thiruvananthapuram district, Kerala, India using standard microbiological techniques. The physicochemical analysis of the soil samples collected from different stations was also done. Conclusion, significance and impact of study Even though the soil/sediment samples were collected from geographically nearby places, the physicochemical parameters showed a significant variation. This may be one of the factors which may trigger the actinomycete diversity in these regions. The diversity of actinomycetes prevalent in this region could serve as a potential source for the discovery of novel biomolecules.
Actinobacteria ; Soil ; Chemical Phenomena

OBJECTIVEThe method of metabonomics based on 1H-nuclear magnetic resonance (1H-NMR) was preliminarily applied to discriminate the oral common Actinomycetes, Actinomyces naeslundii ATCC12104 and Actinomyces israelii ATCC12102.

METHODSSolutions of Actinomyces naeslundii and Actinomyces israelii with same density were made and cultured respectively at BHI liquid culture medium. The concentration of bacteria was determined periodically, and then the growth curves were drawn. The culture solutions in stationary phase of the two bacteria were used to test with the 1H-NMR spectroscopy respectively. The data of 1H-NMR spectroscopy results were analyzed by principal components analysis (PCA).

RESULTSThe PCA showed the obvious clustering phenomena and the points of two groups data stayed differentially together by two clusters. Therefore, the NMR-based metabolomics profiles can discriminate the two different kinds of bacteria.

CONCLUSIONThe analysis technology of metabonomics is expected to be applied to rapid identification of actinomycetes.

In this study, Paeonia suffruticosa roots and rhizospheric soil in five geographic regions which were harvested in October were utilized as experimental materials, then the diversity of endophytic and rhizospheric actinomycetes were investigated by High-throughput sequencing technique. The 1 754 operational taxonomic units (OTUs) were obtained from 129 954 high quality sequences, 1 311 OTUs were detected in rhizospheric actinomycetes and belonged to four classes, four orders, twenty-seven families and ninety-seven genera, thirty-three genera such as Ilumatobacter were found in the five regions rhizospheric soil while three genera such as Longispora were only detected in the Dao-di regions, the dominant genera were Mycobacterium, Nocardioides, Streptomyces. 443 OTUs were obtained in roots and distributed in three classes, three orders, twenty-four families and fifty genera, thirteen genera such as Cryptosporangium were found in the five regions roots while Planosporangium, Luteococcus were only detected in the Dao-di regions, the dominant genera were Nocardioides. Alpha diversity analysis showed that the Shannon and Chao1 index in rhizospheric actinomycetes in Bozhou, Tongling and Nanling region were higher than Heze and Luoyang. Based on principal co-ordinates analysis (PCoA) analysis, the rhizospheric actinomycetes formations were similar in Tongling and Nanling region, at the same in Tongling and Luoyang endophytic actinomycetes. According to heatmap analysis, Bozhou, Tongling and Nanling region rhizospheric actinomycetes showed a close similarity in actinomycetes community structures on phylogenetic analysis, while Tongling, Luoyang and Nanling endophytic actinomycetes showed the same. Our results not only suggested that the rich and diverse actinomycetes resources in P. suffruticosa roots and rhizospheric soil but also revealed rhizospheric actinomycetes in the Dao-di regions had high similarity.
Actinobacteria ; Paeonia ; Phylogeny ; Plant Roots ; Soil Microbiology

Actinomycosis is relatively rare infection which is produced by an anaerobic organism, actinomycetes, normally residing in the mouth, bowel and female genital tract. This disease is characterized by chronic inflammatory induration with abscess and multiple sinus formation. In most cases, the onset of this is preceded by an inflammatory or traumatic history on abdomen but diagnosis can't be made until operation. Recently this disease is treated with antimicrobial therapy and wide surgical excision. We experienced a case of omental actinomycosis and report it with brief review of literatures.
Abdomen ; Abscess ; Actinobacteria ; Actinomycosis* ; Diagnosis ; Female ; Humans ; Mouth ; Omentum