System for detecting microbial contamination

A method for detecting coliform micro-organisms in a liquid specimen, said method comprising the steps of:

• a) providing a hyperbaric chamber for holding a liquid specimen comprising:
• a liquid inlet through which a liquid specimen can enter said hyperbaric chamber,
• a liquid outlet through which said liquid specimen can leave said hyperbaric chamber and adapted for sealably engaging with the liquid inlet of a filter housing, and
• means for pressurizing said hyperbaric chamber;
• providing a filter housing having a liquid inlet and a liquid outlet and housing a liquid-permeable bed of an adsorbent material in between said liquid inlet and said liquid outlet, wherein said adsorbent material adsorbs coliform micro-organisms by electrostatic interaction and wherein said adsorbent material is in a granular form and comprises metal oxides and/or hydroxyapatite;
• loading a liquid specimen into said hyperbaric chamber;
• sealably engaging said hyperbaric chamber with the liquid inlet of said filter housing such that fluid communication between said hyperbaric chamber and said filter housing is allowed by means of a sealed passageway therebetween;
• b) pressurizing said hyperbaric chamber loaded with said liquid specimen, thereby forcing said liquid specimen from said hyperbaric chamber into said filter housing whereby said liquid specimen passes through said liquid-permeable bed of an adsorbent material before leaving said filter housing via said liquid outlet and adsorbing onto the liquid-permeable bed of an adsorbent material said coliform micro-organisms present in said liquid specimen;
• c) continue pressurizing said hyperbaric chamber until an effective amount of said liquid specimen has passed through said liquid-permeable bed of an adsorbent material;
• d) incubating for an effective period of time said liquid-permeable bed of an adsorbent material with a liquid growth medium supplemented with a chromogenic and/or fluorogenic substrate in order to detect enzymatic activity of micro-organisms;
• and
• e) monitoring the development of a chromogenic or fluorescent color to establish the presence or absence of coliform micro-organisms adsorbed to adsorbent material, wherein the presence of coliform micro-organisms adsorbed to said adsorbent material indicates the presence of coliform micro-organisms in said liquid specimen.