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Actinobacteria are Gram-positive bacteria and the prolific producers of bioactive molecules. In the course of drug discovery from actinobacterial sources, some samples were taken from different locations and habitats of Indonesia and isolation of Actinobacteria was conducted thereof. Totally 196 strains of Actinobacteria were isolated, and approximately half of them were characterized by 16S rRNA gene analysis. Around two-thirds of them were detected as Streptomyces. One of the Streptomyces strains, i.e., strain SHP 1-2 produced active extracts against some microbial pathogens. Analysis and isolation of compounds from its extract revealed that two novel molecules, which are indolactam derivatives, were found from it. Polyphasic taxonomy study of strain SHP 1-2 suggested that this strain is a novel species in the Streptomyces group. Another study from different strains suggested that strain MAE-11, isolated from mangrove area, was identified close to Kitasatopora and Streptomyces species and generated active extract against hepatitis C virus (HCV). The extract was known to contain bafilomycin D as the molecule that was responsible for the antiviral activity. Isolate 196526CR was detected as Amycolatopsis species and could produce an extract that showed activity against some tested microbes. The compound analysis and isolation from its extract indicated that nitrosoxacin C possesses property as an antimicrobial compound. Chemotaxonomy study of strain ASO4wet, which was previously isolated from deep-sea in the North Atlantic Ocean, was also conducted and the data supported that ASO4wet belongs to the genus Streptomyces. The strain is described as the novel species., Actinobakterien sind Gram-positive Bakterien und die ergiebigsten Produzenten bioaktiver Moleküle. Im Zuge der Wirkstoffforschung aus Actinobakterien wurden einige Proben an verschiedenen Orten und Lebensräumen Indonesiens entnommen und daraus Actinobakterien isoliert. Insgesamt wurden 196 Aktinobakterien-Stämme isoliert und etwa die Hälfte von ihnen wurde durch 16S-rRNA-Genanalyse charakterisiert. Etwa zwei Drittel von ihnen wurden als Streptomyces identifiziert. Einer der Streptomyces-Stämme, d. h. Stamm SHP 1-2, produzierte aktive Extrakte gegen einige pathogene Mikroorganismen. Nach Analyse und anschließender Isolierung der Inhaltsstoffe konnten zwei neue Substanzen, die zu der Indolactam-Derivaten gehören, gefunden werden. Eine polyphasische Taxonomiestudie des Stammes SHP 1-2 legte nahe, dass dieser Stamm zu einer neuen Spezies in der Gattung Streptomyces-gehört. Eine vergleichende Studie mit verschiedenen Stämmen legte nahe, dass der Stamm MAE-11, der aus Mangrovengebieten isoliert wurde, nahe verwandt mit Kitasatopora- und Streptomyces-Arten ist und einen aktiven Extrakt gegen das Hepatitis C-Virus (HCV) produziert. Es zeigte sich, dass der Extrakt Bafilomycin D als die Substanz enthielt, die für die antivirale Aktivität verantwortlich war. Das Isolat 196526CR wurde als Amycolatopsis-Spezies identifiziert und bildet einen Extrakt, der eine Aktivität gegen einige Mikroorganismen zeigte. Die Analyse der Bestandteile und die Isolierung aus diesem Extrakt zeigten, dass Nitrosoxacin C für die antimikrobielle Eigenschafte verantwortlich ist. Eine chemotaxonomiche Studie des Stammes ASO4wet, der aus der Tiefsee im Nordatlantik isoliert worden war, wurde ebenfalls durchgeführt, und die Daten untermauerten, dass ASO4wet zur Gattung Streptomyces gehört. Der Stamm wird als neue Art beschrieben.

During the course of our ongoing screening for novel biologically active secondary metabolites, the rare Actinobacterium, Nonomuraea sp. 1808210CR was found to produce five unprecedented β-carboline derivatives, nonocarbolines A-E (1-5). Their structures were elucidated from high-resolution mass spectrometry, 1D and 2D nuclear magnetic resonance spectroscopy, and the absolute configuration of 4 was determined by using the modified Mosher method. Nonocarboline B (2) displayed moderate antifungal activity against Mucor hiemalis, while nonocarboline D (4) exhibited significant cytotoxic activity against the human lung carcinoma cell line A-549 with the IC50 value of 1.7 µM.

Polyketides are large group of secondary metabolites that have notable variety in their structure and function. Polyketides exhibit a wide range of bioactivities such as antibacterial, antifungal, anticancer, antiviral, immune-suppressing, anti-cholesterol and anti-inflammatory activity. Naturally, they are found in bacteria, fungi, plants, protists, insects, mollusks and sponges. Streptomyces is a genus of Gram-positive bacteria that has a filamentous form like fungi. This genus is best known as one of polyketides producers. Some examples of polyketides produced by Streptomyces are rapamycin, oleandomycin, actinorhodin, daunorubicin and caprazamycin. Biosynthesis of polyketides involves a group of enzyme activities called polyketide synthases (PKSs). There are three types of PKSs (type I, type II, and type III) in Streptomyces that responsible for producing polyketides. This paper focuses on biosynthesis of polyketides in Streptomyces with three structurally different types of PKSs.

Silver nanoparticle-bacterial cellulose bionanofiber nanocomposite (nano Ag-BSB) has been synthesized by using trisodium nitrate as reducing agent. The arrangement offiber in nano Ag-BSB nanocomposite has random shape after 26 confirmed by scanning electron microscopy (SEM)analysis. Nano Ag-BSB nanocomposite has average 64.1 nm in nanofiber diameter. Fourier infra red spectroscopy and X-ray diffraction analysis showed crystal structure in Ag-BSB nanocomposite is cellulose type L Crystalinity of BSB and Ag-BSB are 94 % and 89 %, respectively.This result showed that presence of silver nanoparticles in BSB decreased crystalinity of BSB. Ag-BSB nanocomposite has good performance in inhibitingE-Coli growth.Keywords: Silver nanoparticle; nanocomposite, bacterial cellulose bionanofibet; silver nanoparticlebacterial cellulose bionanofiber nanocomposit

Selaginella sp belongs to the Selaginellaceae family. It has been used in China and Indonesia as a traditional medicine. It hasseveral medicinal properties including antibacterial, anticardiovascular, and anticancer agent. The aim of the present study was to access the anticancer property of the ethanolic extracts of Selaginella plana Hieron. on T47D breast cancer cell line. The proliferation of T47D cell line was detected by SRB (Sulforhodamine B) assay which was measured at a wavelength of 515 nM. The result showed that the IC50 of the ethanolic extract was determined at 7.03 pg/mL. This significant activity was assumed due to its high total flavonoid content. The totalflavonoid content of the ethanolic extract was 23.04%. Flow cytometry analysis indicated that the extract may undergo the cell death via apoptosis pathway. In conclusion, the ethanolic extract of Selaginella plana Hieron: has considerable activity in inhibiting T47D cell line proliferation.Key words: Selaginella plana Hieron., SulforhodamineB, T47Dcells, anticancer flow cytometry