JPS59109169A - Shaking flask - Google Patents

Abstract

PURPOSE:To increase the dissolved oxygen concentration in a shaking flask for the aerobic cultivation to a sufficiently high level, by attaching a nozzle for the forced injection or exhaustion of oxygen to the wall of the gas-phase of the flask having gas-permeable plug. CONSTITUTION:A shaking flask 1 for carrying out the fermentation in the system is furnished with an opening 3 at the lower side wall contacting with the culture liquid 12, and an oxygen electrode is attached to the opening to measure the dissolved oxygen concentration. The top of the flask is plugged with a cotton plug as the gas-permeable plug 2, and the side wall of the flask is furnished with an opening 5 which can be contacted with the gaseous phase in the system. A nozzle 7 for the introduction of air is attached to the side wall opening 5. The nozzle is made of a stainless steel pipe extended through the rubber plug 6 to the gaseous phase 8, and a filter 9 is attached to the exterior end of the nozzle 7. The metabolized gas such as carbon dioxide gas in the system can be discharged by injecting or exhausting air forcibly through the air pipe 10. Accordingly, the oxygen can be supplied sufficiently to increase the dissolved oxygen concentration, the amount of culture liquid, and the concentration of the cultured microbial cells.

Description

DETAILED DESCRIPTION OF THE INVENTION The invention relates to a flask having a structure suitable for use in aerobic culture, particularly in the field of fermentation chemistry. It is excellent for replenishing and controlling it.

Conventionally, in shake flasks used for aerobic culture, a ventilation stopper such as a foamed silicone stopper is attached to the flask, and natural convection through the ventilation stopper is used to supply oxygen and exhaust the fermentation product gas inside the flask. Ta. However, with such vent plugs, the movement of oxygen and gas into and out of the prefecture is due to artificial and natural expansion, so the rate can exceed the constant rate, and the bacterial concentration within the system increases.1. In this case, the rate of oxygen supply to the culture solution was limited by this diffusion, and the supply of oxygen to the culture solution was insufficient. The present inventor has confirmed that when the dissolved oxygen in the culture solution is almost completely eliminated, the oxygen in the flask air layer is also less than the atmospheric oxygen concentration '/s-Zo. In other words, the culture solution It was confirmed that oxygen diffusion from the vent plug is rate-limiting.This not only limits the growth rate of bacterial cells (but also increases the concentration of GO2a, a metabolic product, in the system). Inhibition occurred, resulting in a drop in the pH of the culture solution.In general, there is often no correlation between culture in flasks and culture in mini jars that supply oxygen; It is thought that the oxygen supply rate is the main cause.

The present invention solves this drawback, and is a flask with a structure in which the vcH hydrogen is fully pumped or inhaled into a flask with a vent plug (discharged or introduced through the vent plug). This method supplies oxygen to the flask air layer at full strength, thereby supplying all the oxygen to the culture medium.In other words, the vent plug, which was conventionally used as an oxygen supply port, is replaced with an exhaust port. Or it can be used as an introduction port.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

Figure 1 shows a shaking flask 1 for fermentation in the system, with holes 3 in the lower side wall that can come into contact with the culture solution 12.
, and install an oxygen electrode 4 therein so that dissolved oxygen in the culture solution can be measured at any time. A cotton plug is loaded on the top of the flask as a ventilation plug 2, an opening 5 is provided in the upper side wall of the flask that can come into contact with a portion of the air inside the system, and an air transfer nozzle 7 is added to the opening 5.

At the attachment point of the nozzle 7, the stainless steel pipe 7 passes through the comb stopper 6 and communicates with the outside of the flask 18. At the outer end of this pipe there is a filter 9 and an air inlet/outlet 10.
By providing this, metabolic gases such as carbon dioxide in the flask can be extracted from the system. When pressure is applied through a nozzle, the amount of compressed air is preferably 1 M or less, although it depends on the strength of the adhesion between the cotton stopper and the flask. If this value is 1 or more, the flask will be under positive pressure, and the cotton plug will float, creating a gap between it and the flask wall, which may cause contamination with bacteria.

If air is drawn through the nozzle, the cotton plug will come into closer contact with the flask wall. In this case, the amount of suction should be too high (it should be less than fvvM as there is a risk of contamination with bacteria).For suction, it is convenient to connect a comb tube to the air outlet 10 and use a peristaltic pump to suction, and in this case, filter 9 is not particularly necessary. Although this example was described using an Erlenmeyer flask, the same thing can be done with a Sakaro flask.

When the present invention is carried out, sufficient oxygen is supplied to the air layer of the flask, so dissolved oxygen can be sufficiently increased, and the culture solution i1 can therefore be increased and the bacterial concentration can also be increased. It will also be possible to confirm the correlation with culture in mini jars. In addition to the above-mentioned one, commonly used vent plugs such as silicone foam plugs and urethane foam plugs can be used as the ventilation plugs.

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[Brief explanation of drawings]

The drawing shows an embodiment of the present invention, in which 2 is a vent plug and 7 is an air transfer nozzle. For patent, applicant Ishikawa Seisakusho Co., Ltd. 4-

Claims (1)

[Claims] 1. A shaking flask, characterized in that the flask container has a vent stopper and a nozzle capable of forcibly injecting or absorbing oxygen into the wall surface of an air layer part of the flask container.