Abstract: A piston limiting structure, including: a cylinder, a piston, and a flange provided with a limiting piece, the cylinder has a piston hole perpendicular to an axial direction of the cylinder and penetrating through the cylinder, and a projection of the piston hole in a penetrating direction is circular. The piston is disposed in the piston hole in a form-fit manner and is slid in the piston hole in a reciprocating manner. A side wall of the piston is provided with a thrust groove, a bottom surface of the thrust groove forms a thrust surface on the side wall of the piston, and the thrust groove does not penetrate through two ends of the side wall of the piston along an axial length of the piston. The limiting piece abuts against the thrust surface.

Abstract: The present disclosure provides a pump body assembly, a heat exchange apparatus, a fluid machine and an operating method thereof. The pump body assembly includes a piston, a shaft, a piston sheath, and a cylinder. The shaft drives the piston to rotate and reciprocate within the piston sheath while rotating. The piston sheath is located in the cylinder, and a compression chamber is defined between an outer circumferential wall of the piston and an inner wall of the cylinder. A pressure relief recess is defined in the outer circumferential wall of the piston or the inner wall of the cylinder at a position corresponding to the compression chamber.

Abstract: A fidaxomicin purification method, comprising: fermenting Actinoplanes sp. HS-16-20 to generate fermented liquid; conducting solid/liquid separation on the fermented liquid, soaking mycelium in an organic solvent, and filtering to obtain a solution containing fidaxomicin; treating the solution with nanofiltration concentrate, and separating to obtain fidaxomicin crude product; conducting preparative column chromatography on the fidaxomicin crude product, eluting with an acid aqueous solution containing an organic solvent, and separating to obtain the refined fidaxomicin product.

Abstract: A fidaxomicin purification method, comprising: fermenting Actinoplanes sp. HS-16-20 to generate fermented liquid; conducting solid/liquid separation on the fermented liquid, soaking mycelium in an organic solvent, and filtering to obtain a solution containing fidaxomicin; treating the solution with nanofiltration concentrate, and separating to obtain fidaxomicin crude product; conducting preparative column chromatography on the fidaxomicin crude product, eluting with an acid aqueous solution containing an organic solvent, and separating to obtain the refined fidaxomicin product.

Abstract: A bacterial strain of Actinoplanes sp. and and the use thereof. The bacterial strain is named Actinoplanes sp. HS-16-20, whose preservation number is CGMCC (China General Microbiological Culture Collection Center) No. 7294. The bacterial strain can be used to generate Fidaxomicin or analogs thereof or compositions containing Fidaxomicin, such as by aerobically fermenting the strain in nutrient medium containing assimilable carbon and/or nitrogen sources. Fidaxomicin has an inhibitory effect on various gram positive bacteria pathogens, and in particular, on Clostridium difficile.

Abstract: A bacterial strain of Actinoplanes sp. and an application thereof. The bacterial strain is named Actinoplanes sp. HS-16-20, whose preservation number is CGMCC No. 7294. The bacterial strain can generate Fidaxomicin, and Fidaxomicin has an inhibitory effect on various gram positive bacteria pathogens, and in particular, on Clostridium difficile.