Abstract. Sanjaya WTA, Khoirunnisa NS, Ismiani A, Hazra F, Santosa DA. 2021. Isolation and characterization of mercury-resistant microbes from gold mine area in Mount Pongkor, Bogor District, Indonesia. Biodiversitas 22: 2656-2666. Exploring novel wild-type microbes is very important to give more flexibility for bioremediation implementation. It is related to discovering strain with higher detoxification ability and more reliable degradation mechanisms. Moreover, novel strain can be used as genetic material for strain development by molecular genetic engineering and production design formulation. The aims of this experiment were to characterize and identify new mercury-resistant microbes, investigate their capacity to accumulate mercury, and analyze the reducing mercury toxicity in bioassay. Four strains of bacteria selected through the screening stage were characterized for their morphological, biochemical, physiological, and molecular genetic characteristics. Considering their characteristics and mercury resistance levels, there are two selected microbial strains: fungus strain Cladosporium halotolerans Hg32 and the bacterial strain Mycolicibacterium peregrinum Hg37 with a mercury resistance level up to 3000 mg L-1. The C. halotolerans Hg32 could remove mercury with the highest potency up to 90.72% at a mercury concentration of 100 mg L-1, while  M. peregrinum Hg37 removes up to 77.10% at mercury concentrations of 10 mg L-1. Toxicity bioassay tests using fish confirmed that C. halotolerans Hg32 and M. peregrinum Hg37 had the ability to detoxify mercury in contaminated water. Both have successfully proven to reduce the mortality rate to below 5%.

Tanah merupakan sumber daya penting bagi kehidupan yang ada di muka bumi.  Tanah menyediakan air, udara dan nutrisi yang dibutuhkan bagi makhluk hidup seperti mikroorganisme tanah dan tanaman.  Tujuan dari penelitian adalah : mengisolasi dan karakterisasi bakteri pelarut fosfat, dan menguji patogenitas isolat bakteri pelarut fosfat pada tanaman tembakau. Penelitian dilakukan di Laboratorium Biologi Tanah, Departemen Ilmu Tanah dan Sumber Daya Lingkungan, Institut Pertanian Bogor, pada bulan Oktober 2017 sampai Januari 2018. hasil isolasi bakteri pada tanah lahan percobaan kampus Institut Pertanian Bogor diperoleh empat isolat potensial yang mempunyai kemampuan tinggi dalam melarutkan fosfat dengan membentuk zona bening (halozone). Hasil pengujian patogenitas pada daun tembakau setelah 48 jam menunjukkan tingkat patogenitas yang berbeda dari masing-masing isolat potensial.  Hasil uji patogenitas pada tanaman tembakau diperoleh dua isolat potensial dari empat isolat terpilih yang kompeten digunakan sebagai pupuk hayati yaitu isolat BPF P (dari tanaman padi) dan BPF J (dari tanaman jagung).