Saprophyte

“ Sternberg's own contributions have been not the least important; and saprophytic bacteria in water, in the soil, in or on the human body, and in food, the whole number of saprophytes described being three hundred and thirty-one. "The merit of a work of this kind," Nature says, "depends not less on the number of species described than on the clearness and accuracy of the descriptions, and Dr. Sternberg has spared no pains to make these as complete as possible." ”

“ Fungi live therefore either as parasites or saprophytes, and as the same species may pass part of its life in a living host to occur at another stage of its development as a saprophyte, it is impossible to distinguish definitely between parasitic and saprophytic forms. The vegetative body of a fungus, that is the portion which is concerned with providing nourishment and preparing the plastic food-substance for the reproductive organs, is known as the mycelium. ”

“ Contagion may take place both by introduction into wounds, and from the mucous membrane of the intestines or lungs, both by vegetative cells and by spores; in intestinal anthrax, however, only by spores. The Bacillus multiplies as soon as it has entered the blood, and the anthrax disease commences. The Bacilli not only give off poison, [40] but also deprive the blood of its oxygen. Vegetative cells only occur in living animals. This species is a facultative parasite which in the first stage is a saprophyte, and only in this condition forms spores. ”

“ These saprophytes act upon the tissues of dead animals and vegetables, and resolve them into simpler substances, which are then ready to serve as nourishment for plants higher in the vegetable kingdom. Thus the processes which we know as fermentation and putrefaction are due to the action of saprophytes. Higher plants in turn furnish food for men and animals, and so the food supply is used over and over in different forms, making what is known as the food cycle. If it were not for bacterial activities vegetation would be robbed of its supply of nourishment, and plant life would speedily end ”

“ With regard to their pilfering habits, such plants are usually proportioned off into two great groups. They either attach themselves to other beings and absorb their juices, in which case they form a mighty host of plants of prey usually known as parasites; or they seek their nurtriment, and find it, in dead and decaying organisms, and are then known as saprophytes, a somewhat hard word to begin with, for which I can not find a popular equivalent, but which merely signifies plants that grow on decomposing matter. ”

“ The remarks made when considering water bacteria apply here also, viz., that an excess of saprophytes acts not only as index of increase of organic matter, but as at first auxiliary, and then detrimental, to pathogenic organisms. It will require accurate knowledge of soil bacteria generally to be able to say which saprophytic germs, if any, have no definite function beyond their own existence. It may be doubted whether the stern behests of nature permit of such organisms. ”

“ It may be unable to penetrate into the plant, and finding no suitable food outside it dies: or it may be satisfied with the traces of organic matter on the epidermis and then lives the life of a saprophyte. Or it may be able to establish a hold-fast on the tender epidermal surface, but without entering the cells, and irritate the developing organ by contact stimulation, inducing slight abnormalities; if in its further, purely superficial growth such an epiphyte covers large areas of the leaf, and especially if the hyphae are dark coloured—e.g. ”

“ Some of the more important saprophytes are those organisms which play an important and useful part in our every-day life, such as, for instance, in the phenomena associated with fermentation, and putrefaction agents which transform dead and decomposing organic matter into their simpler elements, thus completing the great life cycle, and rendering the dead and effete matter again ready for the vital processes. ”

“ They may be looked upon as the nearest existing representatives of the primary forms of life which first obtained the power of working up non-living into living materials, and as playing a correspondingly important rôle in the evolution of life on our globe. The vast majority of bacteria, on the other hand, which are ordinarily termed saprophytes, are saprogenic, i.e. ”

“ A parasite, on the other hand, lives always at the expense of some other organism which is its host, in which it lives and upon which it lives. There is a third or intermediate group, known as "facultative," owing to their ability to act as parasites or saprophytes, as the exigencies of their life-history may demand.
Method of Producing Hydrogen by Kipp's Apparatus for Cultivation of Anaërobes (See page 139)
The saprophytic organisms are, generally speaking, those which contribute most to the benefit of man, and the parasitic the reverse, though this statement is only approximately true. ”

“ As regards disease, the organisms of suppuration are the most common. Liquefying or fermentative bacteria are frequently present, the Proteus family being well represented. In addition there are, according to circumstances, a number of common saprophytes. Now, as we have pointed out, these organisms may act injuriously by some kind of cooperation, or they may by themselves be harmless, and pathological conditions be due to the occasional introduction of pathogenic species. ”

“ The opinions of botanists are at variance, in many cases, about the forms of growth of a particular kind. Some species are pleomorphic (many-formed) while others possess only one form.
The following Bacteria are Saprophytes:—
Cladothrix dichotoma is common in stagnant and running water which is impregnated with organic matter; the cell-chains have false branching. According to Zopf, Leptothrix ochracea is one of the forms of this species which, in water containing ferrous iron (e.g. as FeCO3) , regularly embeds ferric-oxide in its sheath by means of the activity of the protoplasm. ”

“ Saprophytes, organisms that live on organic matter, are merely parasites of the dead, whilst all animals derive their nourishment from the bodies of plants, either directly or indirectly through one or more sets of other animals. It is plain, therefore, that if parasitism is to be employed as a scientific term it must connote something more than mere dependence on another living organism for nutrition. ”

“ However that may be, we may feel confident, though at present there are many common bacteria in soil, as also in water, the life object of which is not ascertained, that as knowledge increases and becomes more accurate this special provisional group will become gradually absorbed into other groups having a part in the economy of nature, or in the production of disease. At present the decomposition, denitrifying, nitrifying,49 and nitrogen-fixing organisms are the only saprophytes which have been rescued from the oblivion of ages, and brought more or less into daylight. ”

“ There is no evidence that their entrance into the body is at all necessary for the continuation of their life processes, or that one case of either of these diseases ever has any connection with any other case; they are true saprophytes. ”

“ Certain highly parasitic bacteria (which grow with difficulty upon the artificial media of the laboratory) can only be isolated with considerable difficulty from associated saprophytic bacteria when cultural methods alone are employed; but if the mixture of parasite and saprophytes is injected into an animal susceptible to the action of the former, the pathogenic organism can readily be isolated from the tissues of the infected animal. ”

“ All prepared food is derived directly or indirectly from other organisms. A few plants capture small insects for the sake of the food derived from their bodies. Parasites, that is, creatures growing on or in a living being (called, therefore, the host) , derive their food directly from it; saprophytes in a similar way obtain their food from a dead organism. There is every possible gradation between parasites and saprophytes ”

“ In fact, the Saprolegnia which causes it is an organism closely allied to the Peronospora, which is the cause of the potato-disease. One distinction may be marked between them, that the Peronospora are parasites depending altogether upon living plants for their support, while the Saprolegnia are essentially saprophytes, that is, they ordinarily derive their nourishment from dead animal and vegetable matters, and are only occasionally parasites upon living organisms. ”

“ Dying-back may also be caused by fungi, and not necessarily parasites, for cases are often observed where saprophytes only are to be found in the necrotic tissues of the cortex, having made their way in through minute cracks, lenticels, etc. ”

“ Although the arteries have been injected, yet we find that sometimes the fluid does not reach the cavities. Any cavity may contain gas or material for decomposition, such as blood, pus, lymph, or as in perforation of the intestines, feces in the abdominal cavity. Besides these we always have the bacteria of decomposition, called saprophytes, which have thoroughly invaded the organs and tissues of the body as soon as sixteen hours after death. Then, if for any reason the fluid has not reached a certain part, fermentation, and putrefaction will immediately set in. ”

“ In some cases these cultures very closely resembled the feathery growth of the bacillus of anthrax.
4. The Saprophytic Bacteria in Soil. This group of micro-organisms is by far the most abundant as regards number. They live on the dead organic matter of the soil, and their function appears to be to break it down into simpler constitution. Specialisation is probably progressing among them, for their name is legion, and the struggle for existence keen. After we have eliminated the economic bacteria, most of which are obviously saprophytes, the group is greatly reduced. ”

“ Decay attacks part of a tree, for instance, and saprophytes set to work at the dead branch, but they are apt to extend their operations to the adjoining living tissues, which die, too, and decay, till in the end the tree may be entirely destroyed. ”

“ Sapraemia#, or septic intoxication, is the name applied to a form of poisoning resulting from the absorption into the blood of the toxic products of pyogenic bacteria. These products, which are of the nature of alkaloids, act immediately on their entrance into the circulation, and produce effects in direct proportion to the amount absorbed. As the toxins are gradually eliminated from the body the symptoms abate, and if no more are introduced they disappear. ”

“ Fig. 37.—One of the legs of Sarcoptes scabiei (× about 450) , showing the stalked sucker and the curious ‘cross-gartering.’ (After Bourguignon.)
The male measures 200 μ to 235 μ in length, by 145 μ to 190 μ in breadth. By preference, he lives under the scales which the presence of the parasite produce [103] on the human host. The female is markedly larger than the male, measuring 330 μ to 450 μ in length by 250 μ to 350 μ in breadth. Her two anterior legs end in stalked suckers, whilst the two posterior end in hairs. ”

“ The saponins (with few exceptions) have the general formula CnH2n–8O10, and by the action of dilute acids they are hydrolysed into sugars and sapogenins, which are usually inert pharmacologically. An alternative name for them, and especially for those which are pharmacologically active, is sapotoxins; on this nomenclature the hydrolytic products are termed saponins. Applied as a snuff to the mucous membrane of the nose, saponin (either in soap- bark or in senega root) promotes a violent sneezing. Solutions injected under the skin are violent local irritants and general depressants. ”

“ In sapremia the blood contains the toxins and dead saprophytic organisms. In septicemia the blood contains both pyogenic toxins and multiplying pyogenic organisms. In sapremia the causative condition is putrid material lodged like a foreign body in the tissues. In septic infection the tissues themselves are suppurating, and both bacteria [Pg 50] and toxins are absorbed by the lymphatics. Of course, septic infection may be associated with septic intoxication or may follow it. ”

“ Three genera of Sarcoptidae, namely Sarcoptes Chorioptes and Psoroptes cause mange or scabies in mammals, the mange produced by Sarcoptes being the most serious form of the disease, because the females of the species which produces it, Sarcoptes scabiei, burrow beneath the skin and are more difficult to reach with acaricides. ”

“ Sapogenin may be separated by evaporating the neutralised liquid to dryness, treating the dry residue with ether, which dissolves out the sapogenin, and finally recovering the substance from the ethereal solution, and crystallising it from hot alcohol. Crystals are readily obtained if the alcoholic solution is allowed to evaporate spontaneously. A solution of saponin exposed to the air gets turbid, and develops carbon dioxide; not unfrequently the solution becomes mouldy. ”

“ They resemble in their organization and agility the spermatozoids of Achlya dioica. They soon become motionless in water, and do not germinate. During the development of these organs, the protoplasm of the utricle which contains them offers at first completely normal characteristics, and disappears entirely by degrees as they increase. De Bary and Pringsheim believe that these organs constitute the antheridia of the species of Saprolegnia to which they belong. ”

“ SOAPWORT. The Soapwort (Saponaria officinalis) grows commonly in England near villages, on roadsides, and by the margins of woods, in moist situations. It belongs to the Caryophyllaceoe, or Clove and Pink tribe of plants; and a double flowered variety of it is met with in gardens. This is Miss Mitford's "Spicer" in Our Village. It is sometimes named "Bouncing Bet," and "Fuller's herb."
The root has a sweetish bitter taste, but no odour. It contains resin and mucilage, in addition to saponin, which is its leading principle, and by virtue of which decoctions of the root produce a soapy froth. ”