Effect of Epiphytic Microorganisms and Exogenous Lactic Acid Bacteria on the Formation of Non-protein Nitrogen During the Ensiling of Alfalfa

Though the lactic acid bacteria are recognized primarily as saccharolytic, several workers have recorded observations on their slow proteolytic activity. Von Freudenreich(1) was the first to record the fact that cultures of these organisms in milk, to which chalk had been added to neutralize the acidity, formed appreciable amounts of soluble nitrogen, and these findings were confirmed by Orla-Jensen (2), Barthel(3), and Barthel & Sandberg(4). Anderegg & Hammer (5), in a study of a large number of strains ofStr. Lactis, found an increase in soluble nitrogen in some cases and a decrease in others, while occasionally the same strain differed in different tests. In general, cultures which clotted rapidly were more inclined to proteolysis than those which were slower in forming acid.Str. citrovorusandStr. paracitrovorusdid not cause protein breakdown. Addition of 0·3% peptone to the milk tended to retard proteolysis or to increase negative values while addition of chalk resulted in more extensive proteolysis. Barthel & Sadler (6) found that starters consisting of mixed cultures of streptococci produced more extensive proteolysis than single species, indicating a symbiotic effect. Sherwood & Whitehead (7) tested the proteolytic powers of several strains ofStr. cremorisin chalk milk cultures and found some active and some comparatively inactive. Two strains appear to have formed surprisingly large amounts of non-protein nitrogen. In general they found that acid-producing power was linked with proteolytic power.

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Changes in carbohydrate and protein fractions during ensiling of alfalfa treated with previously fermented alfalfa juice or lactic acid bacteria inoculants

Animal Production Science ◽

10.1071/an15067 ◽

2018 ◽

Vol 58 (3) ◽

pp. 577

Author(s):

L. Tao ◽

H. Zhou ◽

N.-F. Zhang ◽

B.-W. Si ◽

Y. Tu ◽

...

Keyword(s):

Lactic Acid ◽

Fatty Acid ◽

Lactic Acid Bacteria ◽

Protein Degradation ◽

Volatile Fatty Acid ◽

Fatty Acid Content ◽

Fresh Weight ◽

Protein Nitrogen ◽

Soluble Fibre ◽

Colony Forming Units

The effects of previously fermented juice (PFJ) prepared from alfalfa and lactic acid bacteria (LAB) inoculants on the dynamic changes of nutritive components in ensiled alfalfa after various ensiling periods were investigated by using the Cornell Net Carbohydrate and Protein System. The third-cut alfalfa was harvested at the budding stage, exposed to sunlight, weighed occasionally to estimate the dry matter (DM) content until the actual DM finally obtained was 347.8 g/kg fresh weight, and then chopped to 1–2-cm lengths. Chopped forages were treated with (1) distilled water (control), (2) alfalfa PFJ or (3) LAB at 1 mL/50 g fresh weight. The application amounts of PFJ and LAB to the fresh forage were 8.73 log (colony-forming units/mL) and 7.32 log (colony-forming units/mL) respectively. All silages were prepared in mini-silos of 100-mL polypropylene centrifuge tubes and kept in an incubator at 30°C, and triplicate silos from each treatment were opened after 1, 3, 7, 14 and 35 days of ensiling. Results suggested that silage treated with LAB and PFJ was of better quality than was the control silage, as evidenced by lower volatile fatty acid concentrations, as well as higher lactic acid, sugar, starch, soluble fibre and digestible natural detergent fibre production at various ensiling periods (P < 0.05), and a lower protein degradation as suggested by the low non-protein nitrogen production (P < 0.05). The effect of PFJ on alfalfa fermentation quality and protein degradation was greater than that of LAB, as evidenced by the lower pH value and volatile fatty acid content and the higher concentrations of lactic acid (P < 0.05). In addition, the cost of PFJ for 1 tonne of alfalfa silage is ~1/7–1/5 of that of LAB. In conclusion, adding PFJ to alfalfa forages before preservation as silage is a cost-effective way to improve the silage formation quality; in addition, its effect as a fermentation stimulant may be comparable to, or even better than, that of LAB inoculants at various ensiling periods.

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CHEESE-RIPENING STUDIES: Nitrogen Requirements of Lactic Acid Bacteria: I. THE FRACTIONAL ANALYSIS OF VARIOUS NITROGEN SOURCES USED FOR THE QUANTITATIVE DETERMINATION OF THE SUGAR-FERMENTING ABILITIES OF LACTIC ACID BACTERIA

Canadian Journal of Research ◽

10.1139/cjr32-088 ◽

1932 ◽

Vol 7 (4) ◽

pp. 364-369 ◽

Cited By ~ 2

Author(s):

Blythe Alfred Eagles ◽

Wilfrid Sadler

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Biological Significance ◽

Nitrogen Sources ◽

Protein Nitrogen ◽

Nitrogen Distribution ◽

Cheese Ripening ◽

Fractional Analysis ◽

Laboratory Workers ◽

Commercial Source

A study is being made of the nitrogen requirements of lactic acid bacteria. Employing the method of Wasteneys and Borsook, the nitrogen distribution has been determined in nitrogen sources available commercially and in sources that may be readily prepared by laboratory workers. Forty-three sources have been analyzed. The results of the analyses show that peptic casein digest broth contains from 55 to 63% protein nitrogen, 19 to 25% peptone nitrogen, and 14 to 17% subpeptone nitrogen, according to the particular casein used—when the standard method of preparation is followed. If less casein is used for digestion, or if the period of digestion is reduced, the total amount of nitrogen made available is lower; this being true for the subpeptone nitrogen fraction in particular. In tryptic casein digest broth, 70% of the nitrogen is in the subpeptone nitrogen fraction, and about 28% is found as peptone nitrogen. The broth prepared from one commercial source presents a nitrogen distribution picture that is something of a composite of the nitrogen distribution in the standard casein digest and the tryptic casein digest.When the nitrogen sources fractionated are employed as the substrate for fermentation studies, it will be seen that whilst the suitability of a source is not always fully indicated by the nitrogen distribution picture, the biological significance of the nitrogen distribution in the sources is, on the whole, reflected in the influence on the sugar-fermenting abilities of the lactic acid bacteria reported upon.

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161. Studies in Cheddar cheese. VI. The degradation of milk proteins by lactic acid bacteria isolated from cheese, alone, with sterile rennet and with whole rennet

Journal of Dairy Research ◽

10.1017/s0022029900002089 ◽

1937 ◽

Vol 8 (2) ◽

pp. 238-244 ◽

Cited By ~ 3

Author(s):

J. G. Davis ◽

W. L. Davies ◽

A. T. R. Mattick

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Amino Nitrogen ◽

Milk Proteins ◽

Cheddar Cheese ◽

Protein Breakdown ◽

Protein Nitrogen

It has been shown by experiments in milk that the enzymes of commercial rennet in conjunction with the lactic acid bacteria occurring in Cheddar cheese can bring about protein breakdown similar in extent to that found in the ripe cheese as far as the non-protein nitrogen is concerned. The amino nitrogen produced is, however, much less than in cheese. This may be ascribed to the higher pH of cheese as compared with that of the milk cultures, since acidity adversely affects the peptidases present. Attention is drawn to the differences between the conditions.

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Microbiome: Structures from Lactic Acid Bacteria

PSI Structural Genomics Knowledgebase ◽

10.1038/sbkb.2012.159 ◽

2013 ◽

Author(s):

Arianne Heinrichs

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria

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Lactic acid bacteria and yeasts in kefir grains and kefir made from them

Journal of Industrial Microbiology & Biotechnology ◽

10.1038/sj.jim.7000186 ◽

2002 ◽

Vol 28 (1) ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

E Simova ◽

D Beshkova ◽

A Angelov ◽

Ts Hristozova ◽

G Frengova ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Kefir Grains

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Method of separation of major off-odor component and change of components of Gastrodia elata Blume fermented by lactic acid bacteria

10.1055/s-0037-1608346 ◽

2017 ◽

Author(s):

S Young Eun ◽

L In Sok ◽

S Eun Ju ◽

C Min Kyung ◽

H Hyu Ah ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Gastrodia Elata ◽

Gastrodia Elata Blume

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Development of biotechnology for gluten-free sourdough bakery products with a new microbial composition

Khleboproducty ◽

10.32462/0235-2508-2020-29-12-59-63 ◽

2020 ◽

Vol 29 (12) ◽

pp. 59-63

Author(s):

O.I. Parakhina ◽

◽

M.N. Lokachuk ◽

L.I. Kuznetsova ◽

E.N. Pavlovskaya ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Culture ◽

Comparative Assessment ◽

Starter Cultures ◽

Bakery Products ◽

Gluten Free ◽

Microbial Composition ◽

Fermentative Activity ◽

Theoretical Foundations

The research was carried out within the framework of the theme of state assignment № 0593–2019–0008 «To develop theoretical foundations for creating composite mixtures for bakery products using physical methods of exposure that ensure homogeneity, stability of mixtures and bioavailability of nutrients, to optimize diets population of Russia». The data on the species belonging of new strains of lactic acid bacteria and yeast isolated from samples of good quality gluten-free starter cultures are presented. A comparative assessment of the antagonistic and acid-forming activity of strains of lactic acid bacteria and the fermentative activity of yeast was carried out. The composition of microbial compositions from selected strains of LAB and yeast was developed. The influence of the starter culture on the new microbial composition on the physicochemical, organoleptic indicators of the bread quality and resistance to mold and ropy-disease was investigated.

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