The development and world-wide spread of multidrug-resistant (MDR) bacteria have a high concern in the medicine, especially the extended-spectrum of beta-lactamase (ESBL) producing Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA). There are currently very limited effective antibiotics to treat infections caused by MDR bacteria. Peat-soil is a unique environment in which bacteria have to compete each other to survive, for instance, by producing antimicrobial substances. This study aimed to isolate bacteria from peat soils from South Kalimantan Indonesia, which capable of inhibiting the growth of Gram-positive and Gram-negative bacteria. Isolates from peat soil were grown and identified phenotypically. The cell-free supernatant was obtained from broth culture by centrifugation and was tested by agar well-diffusion technique against non ESBL-producing E. coli ATCC 25922, ESBL-producing E. coli ATCC 35218, methicillin susceptible Staphylococcus aureus (MSSA) ATCC 29,213 and MRSA ATCC 43300. Putative antimicrobial compounds were separated using SDS-PAGE electrophoresis and purified using electroelution method. Antimicrobial properties of the purified compounds were confirmed by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). In total 28 isolated colonies were recovered; three (25PS, 26PS, and 27PS) isolates produced proteins with strong antimicrobial activities against both reference strains. The substance of proteins from three isolates exerted strong antimicrobial activity against ESBL-producing E. coli ATCC 35,218 (MIC = 2,80 µg/mL (25PS), 3,76 µg/mL (26PS), and 2,41 µg/mL (27PS), and MRSA ATCC 43,300 (MIC = 4,20 µg/mL (25PS), 5,65 µg/mL (26PS), and 3,62 µg/mL (27PS), and also had the ability bactericidal properties against the reference strains. There were isolates from Indonesian peat which were potentials sources of new antimicrobials.

耐多药（MDR）细菌的发展和在世界范围内的传播在药物中引起高度关注，特别是产生β-内酰胺酶（ESBL）的大肠杆菌和耐甲氧西林金黄色葡萄球菌的广谱（MRSA）。当前，用于治疗由MDR细菌引起的感染的有效抗生素非常有限。泥炭土是一种独特的环境，在这种环境中，细菌必须相互竞争才能生存，例如，通过产生抗菌物质来生存。这项研究旨在从印度尼西亚南加里曼丹省的泥炭土壤中分离细菌，该细菌能够抑制革兰氏阳性和革兰氏阴性细菌的生长。表皮生长出泥炭土壤分离物。通过离心从肉汤培养物中获得无细胞的上清液，并通过琼脂良好扩散技术对未产生ESBL的大肠杆菌ATCC 25922，产生ESBL的大肠杆菌ATCC 35218，对甲氧西林敏感的金黄色葡萄球菌进行了测试（MSSA）ATCC 29,213和MRSA ATCC43300。使用SDS-PAGE电泳分离推定的抗菌化合物，并使用电洗脱方法纯化。通过测量最小抑菌浓度（MIC）和最小杀菌浓度（MBC）来确认纯化化合物的抗菌性能。总共回收了28个分离的菌落。三种分离物（25PS，26PS和27PS）分离出的蛋白对两种参考菌株均具有强大的抗菌活性。来自三种分离物的蛋白质物质对产生ESBL的大肠杆菌具有强大的抗菌活性 ATCC 35,218（MIC = 2,80μg/ mL（25PS），3.76μg/ mL（26PS）和2,41μg/ mL（27PS）和MRSA ATCC 43,300（MIC = 4,20μg/ mL（ 25PS），5,65 µg / mL（26PS）和3,62 µg / mL（27PS），还具有对参考菌株的杀菌性能，其中有印尼泥炭的分离物是新抗菌剂的潜在来源。