Leuconostocs were first isolated in by Cienkowski. For example, L. So, it may be used as biopreservative. Leuconostoc in general is important to fermentation of vegetables.
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Medical use[ edit ] Levofolinic acid Folinic acid is given following methotrexate as part of a total chemotherapeutic plan, where it may protect against bone marrow suppression or gastrointestinal mucosa inflammation.
No apparent effect is seen on pre-existing methotrexate-induced nephrotoxicity. This includes reductions in nausea, abdominal pain, abnormal liver blood tests, and mouth sores. In this case, folinic acid is not used for "rescue" purposes; rather, it enhances the effect of 5-fluorouracil by inhibiting thymidylate synthase. Folinic acid is also sometimes used to prevent toxic effects of high doses of antimicrobial dihydrofolate reductase inhibitors such as trimethoprim and pyrimethamine.
It may be prescribed in the treatment of toxoplasmosis retinitis , in combination with the folic acid antagonists pyrimethamine and sulfadiazine. Folinic acid is also used in the treatment of cerebral folate deficiency , a syndrome in which the use of folic acid cannot normalize cerebrospinal fluid levels of 5-MTHF.
This may produce severe adverse effects or even death. Some adverse effects that have occurred, particularly in elderly patients, include severe enterocolitis , diarrhea, and dehydration. Folinic acid has been shown to decrease the efficacy of sulfamethoxazole-trimethoprim in the treatment of Pneumocystis jirovecii formerly known as Pneumocystis carinii , a common cause of pneumonia in AIDS patients.
It is readily converted to other reduced folic acid derivatives e. Since it does not require the action of dihydrofolate reductase for its conversion, its function as a vitamin is unaffected by inhibition of this enzyme by drugs such as methotrexate.
This is the classical view of folinic acid rescue therapy. In s, however, folinic acid was found to reactivate the dihydrofolate reductase itself even when methotrexate exists. Although the mechanism is not very clear, the polyglutamylation of methotrexate and dihydrofolate in malignant cells is considered to play an important role in the selective reactivation of dihydrofolate reductase by folinic acid in normal cells. Folinic acid has dextro- and levorotary isomers.
Both levoleucovorin the levorotary isomer and racemic folinic acid a mixture of both isomers have similar efficacy and tolerability. This resulted in it being called "citrovorum factor," meaning citrovorum growth factor. It had an unknown structure, but was found to be a derivative of folate that had to be metabolized in the liver before it could support growth of L.
The synthesis of citrovorum factor by liver cells in culture was eventually accomplished from pteroylglutamic acid in the presence of suitable concentrations of ascorbic acid. The simultaneous addition of sodium formate to such systems resulted in increased citrovorum factor activity in the cell-free supernatants producing, as now known, the 5-formyl derivative , and from this method of preparation of large amounts of the factor, its structure as levo-folinic acid 5-formyl tetrahydrofolic acid was eventually deduced.
However, folinic acid is a vitamer for folic acid and has the full vitamin activity of this vitamin. Levofolinic acid and its salts are the 2S- form of the molecule.
They are the only forms of the molecule that are known to be biologically active. It is generally administered as the calcium or sodium salt calcium folinate INN , sodium folinate, leucovorin calcium, leucovorin sodium.
External links Leuconostoc  is a genus of gram-positive bacteria , placed within the family of Leuconostocaceae. They are generally ovoid cocci often forming chains. Leuconostoc spp. All species within this genus are heterofermentative and are able to produce dextran from sucrose. They are generally slime-forming.
Vozragore Glucose and rhamnose were the major reducing sugar constituents. Leuconostoc is a coccus, often lenticular on agar and usually occurs in pairs or chains. The identity of strain P of Leuconostoc mesenteroides. Stimulation of the growth of Leuconostoc oenos by tomato juice.