Test tube for easy enumeration and cultivation of anaerobic and facultatively anaerobic microorganisms

• US 4,140,489 A
• Filed: 02/07/1977
• Issued: 02/20/1979
• Est. Priority Date: 02/07/1977
• Status: Expired due to Term

• Current Assignee: Sun Y. Lee
• Original Assignee: Sun Y. Lee
• Inventors: Lee, Sun Y.
• Primary Examiner(s): Reese, Robert M.
• Application Number:
  US05/766,220
• Time in Patent Office: 743 Days
• Field of Search: 23/259, 23/292, 195/127, 356/246, 215/1 R, 215/6
• US Class Current: 435/39
• CPC Class Codes: B01L 3/5082 Test tubes per se
• CPC Class Codes: C12M 23/08 Flask, bottle or test tube
• CPC Class Codes: C12M 23/34 Internal compartments or partitions
• CPC Class Codes: C12M 25/06 Plates; Walls; Drawers; Multilayer plates
• CPC Class Codes: C12Q 1/06 Quantitative determination

Abstract

A test tube having an inner tube that allows one to insert a bar to create a dark background is described. This system is actually an ordinary or screw-capped test tube with a smaller sized test tube inverted and fused to the bottom. The design permits a thin layer of any agar medium to solidify around the inside edge of the larger tube. The colonies developed in the agar can then be easily counted by creating a dark background by inserting a dark colored rod through the opening of the inner tube.

Alternatively, a permanently dark-colored inner tube can be inverted and fused to the bottom of the outer tube. In this case, it is not necessary to insert a rod to create a dark background and the enumeration of microbial colonies is as easy as the method described above.

Claims

1. The method of cultivating and enumerating anaerobic and facultatively anaerobic microorganisms, comprising:

(a) cultivating microorganisms in an agar medium in a culture tube having concentric inner and outer tube walls forming an annular area therebetween and containing said agar, wherein the tube walls have first and second ends in corresponding directions, the first end of the outer tube wall forming an opening for receiving the agar and microorganisms and having sealing means closing the first end during cultivation, the second end of the outer tube wall being connected to the second end of the inner tube wall, the first end of the inner tube wall being sealed and spaced inwardly from the first end of the outer tube wall, and the second end of the inner tube wall being open and having an internal longitudinal passageway extending to the sealed first end thereof;

(b) inserting colored background medium into said longitudinal passageway of the inner tube wall; and

(c) enumerating the cultivated microorganisms against said background.

2. A device for enumeration and cultivation of microbial colonies comprising, in combination:

(a) a test tube-like tube having

(1) inner and outer concentric tube walls forming an annular area therebetween for containing growth medium for the microbial colonies, the inner wall forming an internal longitudinally extending passageway for receiving background medium therein, the inner and outer tube walls having first and second longitudinal ends in respectively corresponding directions, the first end of the outer tube wall forming an opening for receiving growth medium and microbial organisms to be cultivated therein, wherein the diameter of the mouth is substantially greater than the distance between the inner and outer tube walls and the distance between said inner and outer tube walls is narrower than the diameter of said passageway;

(2) an end wall joining the second end of the outer wall and the second end of the inner wall for sealing the annular area between the outer and inner walls at the second ends of the tube walls, the second end of the inner tube wall forming an opening into said passageway, the outer tube wall being of transparent material for allowing enumeration of microbial colonies in the annular area; and

(3) sealing means closing the first end of the inner tube wall;

(b) cap means engageable with said opening in the first end of the outer tube wall for sealing said opening; and

(c) colored background medium insertable into said passageway through said second end of the inner tube wall.