ANAEROBIC RESPIRATION 6 1 



From this table it is evident that for molds the ratio 

 COo: CjHsOH corresponds approximately to the equation of 

 alcoholic fermentation. With seed-plants on the other hand, the 

 theoretically correct ratio of alcoholic fermentation is an excep- 

 tion and an excess of carbon dioxide is always produced. An 

 abundant formation of CO2 occurs in some cases without the 

 shghtest production of alcohol. Potato tubers and the fruiting 

 bodies of Psalliota campestris behave thus. In the above experi- 

 ments of Kostychev the fruiting bodies of Psalliota gave off 

 1563.5 or 1364.4 mg. of COo but formed no trace of ethyl alcohol. 

 These extreme cases admit of two explanations. Either a differ- 

 ent tvpe of anaerobic respiration is here exhibited, which has 

 nothing to do with alcohohc fermentation and exists without the 

 participation of enzymes of fermentation, or the alcohol or its 

 forerunner (acetaldehydel etc.) which perhaps is formed, is 

 consumed immediately after its formation and there is no 

 accumulation of alcohol. This point will be treated in detail 

 in the next section. Here it suffices to refer to the fact that 

 peptone cultures of Aspergillus niger, which hkewise exhibit 

 no production of alcohol in the absence of oxygen, are found to 

 contain no zymase, according to the results of Kostychev and 

 M. Afanassjewa.^ They are unable to ferment any added 

 susar. However, after some time such cultures also produce 

 enzymes of fermentation if they are left on sugar solutions wilh 

 complete access to air. They then attain the capacity to produce 

 large amounts of alcohol in the absence of air. From these 

 results it may be concluded that the anaerobic respiration of 

 peptone cultures of Aspergillus niger is in fact a process sui 

 generis which has nothing in common with alcoholic fermenta- 

 tion. In the following table of Boysen-Jensen'- we again find 

 very different values for COorCoHjOH. These latest studies 

 have supported the most important results of Kostychev. 



Plant Materi.^l CO2: C2H5OH 



Cotyledons of peas 100: 65 



Cotyledons of peas i°°= ^^ 



Roots of Dauciis Carota io°- 9i 



Roots of Daucus Carota ^°°'- ^^ 



1 Kostytschew, S. tmd M. Afanassjewa. Jahrb. f. wiss. Bot. 60: 628. 1921. 



2 Boysen-JePsen. P. Det. kgl. danske videnskab. selskab. biol. meddel. 4: i- 1923- 



