Nipah worm (Namalycastis rhodochorde) belongs to the Polychaeta group that lived in the Nypa fruticans mangrove sediment in West Kalimantan. It has the potential to be cultivated because it has a high economic value in aquaculture. Feed aspect is an essential part of its cultivation, through improving the quality of feed by using probiotics isolated from its natural habitat, such as actinomycetes. These bacteria are known capable of producing secondary and primary metabolites. These metabolites are expected to increase immunity and biomass of worms. The purpose of this study was to isolate and determine the composition and characteristics of actinomycetes derived from mangrove sediment, gastrointestinal and faecal pellets of nipah worm that are potential as probiotic for feed formulation. Isolation and characterization of actinomycetes was conducted by pour plate method on SCA, ISP2, ISP3, ISP4, and ISP5 media; while characterization was by determining morphological characteristics of colonies, cell structure, and biochemical tests. Identification of the isolates referred to Bergey’s Manual of Determinative Bacteriology. The results showed that twelve isolates of actinomycetes had been found. Six isolates were from mangrove substrate, four isolates from fecal pellets and two isolates from the gastrointestinal tracts. All isolates were closely related to the genus Streptomyces.

Nipah 蠕虫 ( Namalycastis rhodochorde ) 属于生活在Nypa fruticans中的多毛纲组西加里曼丹的红树林沉积物。它具有养殖潜力，因为它在水产养殖中具有很高的经济价值。饲料方面是其培养的重要组成部分，通过使用从其自然栖息地（如放线菌）中分离出来的益生菌来提高饲料质量。已知这些细菌能够产生次级和初级代谢物。这些代谢物有望增加蠕虫的免疫力和生物量。本研究的目的是分离和确定来自红树林沉积物、尼帕蠕虫胃肠道和粪便颗粒的放线菌的组成和特征，这些放线菌有可能作为饲料配方中的益生菌。在SCA、ISP2、ISP3、ISP4和ISP5培养基上采用倾板法对放线菌进行分离和表征；而表征则是通过确定菌落的形态特征、细胞结构和生化测试。分离株的鉴定参考了伯杰的确定性细菌学手册。结果表明，已发现十二株放线菌。6 株来自红树林基质，4 株来自粪便颗粒，2 株来自胃肠道。所有分离株都与该属密切相关链霉菌。