USE OF SAPONIFIED TALL OIL FATTY ACID

FIELD OF THE INVENTION

The invention relates to use of a tall oil fatty acid which is modified by saponification.

BACKGROUND OF THE INVENTION

Imbalances in microbial populations and growth of harmful bacteria in the digestive tract of animals can cause significant losses in animal growth and production. These imbalances manifest themselves as intestinal disorders such as diarrhea. While micro ^¬ bial infections of animals have been prevented by the use of e.g. antibiotics and other agents that prevent the growth of microorganisms, stricter regulations on their use are expected. Generally, there is an in ^¬ creasing demand for ingredients for use in animal feeding that can modulate the microbial population in the animal digestive tract but which are readily available, well tolerated and environmentally friend- ly.

Fractional distillation of crude tall oil, obtained as a by-product of the Kraft process of wood pulp manufacture, produces distilled tall oil (DTO) which typically comprises over 10% resin acids and less than 90% fatty acids. Further refinement of dis ^¬ tilled tall oil produces tall oil fatty acid (TOFA) , which is available in a variety of compositions dif ^¬ fering in the fatty acids and resin acids content. Be ^¬ cause TOFA is an inexpensive source of fatty acids, it has previously been used in animal nutrition as an en ^¬ ergy source. For instance, GB 955316 discloses the use of alkali metal salts of tall oil fatty acids to im ^¬ prove weight gain and nitrogen retention in ruminant animals . PURPOSE OF THE INVENTION

The purpose of the invention is to provide a new type of modified tall oil fatty acid/feed supple ^¬ ment for use in the modulation of microbial population of the animal digestive tract.

The present inventors have surprisingly found that saponification of TOFA improves the solubility of its components and resin acids in the digestive tract of an animal in particular and significantly increases its effectiveness in the modulation of microbial popu ^¬ lation of the animal digestive tract.

SUMMARY

Use of a tall oil fatty acid which is modi- fied by saponification according to the present invention is characterized by what is presented in claim 1.

DETAILED DESCRIPTION OF THE INVENTION

FIG la Percentage of lactic acid in the ileal simulation as a response to saponified TOFA and digested saponified TOFA concentrations.

FIG lb Percentage of acetic acid in the ileal simulation as a response to saponified TOFA and digested saponified TOFA concentrations.

FIG lc The number of bacteria of the genus Lactobacillus in the ileal simulation samples as a response to saponified TOFA and dried saponified TOFA concentrations.

FIG Id The number of bacteria of the genus Streptococcus in the ileal simulation samples as a response to saponified TOFA and dried saponified TOFA concentrations .

FIG 2a Weight of the chicks on day 11 as a response to saponified TOFA concentrations. FIG 2b Feed conversion ratio for days 1-11 as a response to saponified TOFA concentrations.

FIG 2c Ratio between acetic and lactic acids in ileal contents as a response to saponified TOFA concentrations.

FIG 2d Proportion of samples with Lactobacil ^¬ lus spp count over l*10 ¹² /g digesta fresh weight as a response to saponified TOFA concentrations.

The present invention is based on the reali- zation that tall oil fatty acid which is modified by saponification can be used in the modulation of microbial population of the animal digestive tract.

The modulation of microbial population of the animal digestive tract is carried from homofermenta- tive towards heterofermentative metabolical route and in one embodiment of the present invention it improves the feed utilization (improved nutritional value) . In another embodiment of the present invention, the modu ^¬ lation of microbial population of the animal digestive tract improves the feed conversion ratio.

The term "tall oil fatty acid" or "TOFA" should be understood as referring to a composition ob ^¬ tained by distillation of crude tall oil and further refinement of distilled tall oil. TOFA or TOFA which is modified by saponification typically comprises 90- 98% (w/w) fatty acids. Further, TOFA or TOFA which is modified by saponification may comprise 1-10% (w/w) resin acids.

Resin acids are known to have antimicrobial, including antibacterial, properties. However, the pre ^¬ sent inventors have found that resin acids of TOFA are poorly soluble in digestive juices and tend to precip ^¬ itate in the digestive tract of an animal. Therefore their effectiveness in the digestive tract is less than optimal. The modification of TOFA improves the solu ^¬ bility of its components and resin acids in the diges ^¬ tive tract of an animal.

In this context, the term "tall oil fatty ac- id which is modified by saponification" or "TOFA which is modified by saponification" should be understood as referring to TOFA that is chemically modified so as to improve the solubility of its components and resin ac ^¬ ids in the digestive tract of an animal in particular.

In one embodiment of the present invention, the tall oil fatty acid which is modified by saponifi ^¬ cation for use according to the present invention comprises 1-10% (w/w) of resin acids.

In one embodiment of the present invention, TOFA or TOFA which is modified by saponification comprises 2-9 % (w/w) resin acids.

In one embodiment of the present invention, TOFA or TOFA which is modified by saponification comprises 5-9% (w/w) resin acids.

In this context, the term "resin acids" should be understood as referring to a complex mixture of various acidic compounds comprised by tall oil which share the same basic skeleton including a three- fused ring. The exact composition of the resin acids present in TOFA varies e.g. according to the species of the trees the TOFA is obtained from and the pro ^¬ cessing conditions under which it is manufactured. Resin acids typically include compounds such as abiet- ic acid, dehydroabietic acid, levopimaric acid, neoab- ietic acid, pimaric acid and isopimaric acid, only to mention a few .

In one embodiment of the present invention, TOFA or TOFA which is modified by saponification comprises 90-98% (w/w) of fatty acids.

Various processes for the saponification of

TOFA using e.g. NaOH or CaOH are known to a person skilled in the art. In one embodiment of the present invention, the TOFA which is modified by saponification, the TOFA soap, according to the present invention is dried. The TOFA which is modified by saponification can be dried by spray drying, drum drying or by any other known suitable drying method.

The present invention also relates to a feed supplement comprising the tall oil fatty acid which is modified by saponification according to the invention.

In one embodiment of the present invention, the feed supplement is effective in the modulation of microbial population of the animal digestive tract.

In one embodiment of the present invention, the feed supplement comprises a tall oil fatty acid which is modified by saponification and which compris ^¬ es 1-10% (w/w) resin acids.

In one embodiment of the present invention, the feed supplement comprises a tall oil fatty acid which is modified by saponification and which compris- es 2-9 % (w/w) resin acids.

In one embodiment of the present invention, the feed supplement comprises a tall oil fatty acid which is modified by saponification and which comprises 5-9% (w/w) resin acids.

In this context, the term "feed supplement" should be understood as referring to a composition that may be added to a feed or used as such in the feeding of animals. The feed supplement may comprise different active ingredients. The feed supplement may be added in the feed in a concentration of 0.0001 - 5 kg//ton of dry weight, preferably 0.005 - 1 kg/ton, most preferably 0.01 - 0.1 kg/ton of the dry weight of the total amount of the feed. The TOFA which is modi ^¬ fied by saponification or the feed supplement compris- ing the TOFA which is modified by saponification according to the invention may be added to the feed or feed supplement as such, or it may in general be fur ^¬ ther processed as desired.

Further, the TOFA which is modified by saponification or the feed supplement comprising the TOFA which is modified by saponification according to the invention may be added to the feed or feed supplement, or it may be administered to an animal separately (i.e. not as a part of any feed composition) .

In this context, the term "feed composition" or "feed" should be understood as referring to the to ^¬ tal feed composition of an animal diet or to a part thereof, including e.g. supplemental feed, premixes and other feed compositions. The feed may comprise different active ingredients.

In one embodiment of the present invention, the feed supplement comprises TOFA which is modified by saponification and which is absorbed into a carrier material suitable for the feed composition such as sugarbeet pulp.

In one embodiment of the present invention, the feed supplement comprises TOFA which is modified by saponification and which is dried.

The present invention also relates to a feed composition comprising the feed supplement according to the invention.

In one embodiment of the present invention, the feed composition comprises the feed supplement in an amount of 0.00001 - 0.5 % (w/w) , preferably 0.0005 - 0.1 % (w/w), most preferably 0.001 - 0.01 % (w/w) of the dry weight of the total amount of the feed.

In one embodiment of the present invention, the feed composition comprises the feed supplement in an amount of 0.0005 - 0.1 % (w/w) of the dry weight of the total amount of the feed.

The modified tall oil fatty acid or feed sup ^¬ plement according to the invention is produced by sa ^¬ ponification. The method comprises the steps of adding a base to an aqueous TOFA solution and heating the mixture. The mixture is stirred during the heating step. The mixture is heated at a temperature of 80 - 120 °C, preferably at 85 - 95 °C, for a period of 1 - 3 hours, preferably for 2 hours.

Any base suitable for saponification, such as an alkali metal hydroxide, can be used as the base.

In one embodiment of the present invention, the base that is used is a sodium or potassium hydrox- ide.

In one embodiment of the present invention, the method of producing a saponified tall oil fatty acid or feed supplement further comprises a step of drying. The dying can be carried out by spray drying, drum drying or by by any other known drying method.

The invention also relates to a method of modulating microbial population of the animal diges ^¬ tive tract comprising the step of administering to an animal the tall oil fatty acid which is modified by saponification according to the invention.

In this context, the term "harmful bacteria" should be understood as referring to any bacteria that is capable of affecting the digestive tract or health of an animal in an adverse manner, including competi- tion for nutrients with the host animal. In this con ^¬ text, the term "microbial population" should be under ^¬ stood as referring to the microorganisms that inhabit the digestive tract, including the Bacteria and Ar- chaea domains and microscopic members of the Eukaryote domain and also intestinal parasites. The microbial population will vary for different animal species de ^¬ pending on e.g. the health of an animal and on environmental factors .

In this context, the term "animal" should be understood as referring to all kinds of different ani ^¬ mals, such as monogastric animals, ruminants, fur ani ^¬ mals, pets and aquaculture. Non-limiting examples of different animals, including offspring, are cows, beef cattle, pigs, poultry, sheep, goats, horses, foxes, dogs, cats and fish.

In one embodiment of the present invention, the TOFA which is modified by saponification is administered to an animal in an effective amount.

The present invention has a number of ad ^¬ vantages. TOFA is a readily available, natural, low- cost and environmentally friendly material. Further, it is non-toxic and well tolerated. The invention is effective in modulating the composition of the micro- biota in the animal digestive tract to a direction that is beneficial for animal performance. Subsequent ^¬ ly, other benefits of the invention are e.g. improved animal productivity, improved feed conversion ratio, higher product quality, uniformity, nutritional value and food and product safety. The invention also allows the production of feed compositions and supplements at low cost.

The embodiments of the invention described hereinbefore may be used in any combination with each other. Several of the embodiments may be combined to ^¬ gether to form a further embodiment of the invention. A product, a method or a use, to which the invention is related, may comprise at least one of the embodi ^¬ ments of the invention described hereinbefore.

EXAMPLES

In the following, the present invention will be described in more detail.

EXAMPLE 1.

This experiment was conducted to study the effect of saponified TOFA soap with 5 % resin acids with or without Sugar Beet Pulp (SBP) carrier on the microbial microbial population and fermentation of broiler chick ileum in vitro.

The saponified TOFA was manufactured by add ^¬ ing 140 mg of NaOH (sodium hydroxide) to 1 gram of TOFA, adding enough water to adjust the total dry matter (TOFA) percentage of the mixture to 18-20%, heat ^¬ ing the mixture to + 90 °C, keeping the temperature at + 90 °C for 120 minutes, during which time the mixture was gently stirred at 15 min intervals.

Experiment

Ileal contents of 40-days old broiler chicks were used for the simulation media and as inoculants in the simulation models. The trial treatments were prepared from a batch of saponified TOFA soap.

Preparations of TOFA with 5% resin acids were produced :

1. Saponified TOFA (FOR7) with 20 % dry matter content

An aliquot of the TOFA soap was heated to 90°C, mixed with finely ground SBP powder, and dried to contain 375 g dry TOFA soap/kg.

2. Saponified and digested TOFA (FOR7) Gastrointestinal digestion of the saponified

TOFA: Part of the liquid TOFA soap and the carrier- absorbed TOFA soap was digested by a pepsin-HCl treatment (pH 2.25) followed by a pancreatin bile- acid-NaOH treatment (pH 6.2) in a dilution series. The digestion was made to evaluate whether the products would resist the conditions of the upper gastrointes- tinal tract before they enter the distal intestine with higher microbial activity.

The simulation was conducted in a total of 160 2-ml plastic microcentrifuge vials, in 1.5 ml vol ^¬ ume, with 10 hours simulation time. Samples were tested at four concentrations of the dry matter of TOFA: 0%, 0.005%, 0.01%, 0.01% and 1%. All the simulation samples were analysed for short chain fatty acids and the total number of mi ^¬ crobes. In addition, selected samples were analysed for a number of microbial species or groups by quanti- tative real-time PCR (qPCR) . Ileal simulation samples were analysed for lactobacilli and streptococci.

Results

The results are illustrated in Figures la - Id. In the ileal simulation model, TOFA soap at 1 kg/ton level increased the concentrations of acetic and propionic acids and decreased the concentration of lactic acid (Figures lb and la) . This suggests modula ^¬ tion of microbial metabolism from homofermentative to ^¬ wards heterofermentative metabolical route, which can be seen as a very positive change improving the feed conversion ratio. TOFA soap amendment at 0.1 kg/ton negatively affected the population numbers of lactoba ^¬ cilli and streptococci (Figures lc-ld) , all of which are lactate producers. The total bacterial numbers in the ileum were not affected by the TOFA soap, which may indicate that other bacterial populations were in ^¬ creased as a response to the TOFA soap amendment. Pre- digestion of the TOFA soap affected many of the stud ^¬ ied parameters, while the sugar beet pulp carrier had little effect on the fermentation

EXAMPLE 2.

This experiment was conducted to study the effect of saponified TOFA with 5% resin acids on nu ^¬ tritional value of feed and feed conversion ratio. The saponification of the TOFA was conducted as described in Example 1.

Experiment

240 newly-hatched, male Ross 508 broiler chicks were allocated into 40 open pens, six birds per pen and eight replicate pens per feeding treatment. TOFA soap with 5% resin acid content was ab ^¬ sorbed into ground sugar beet pulp (SBP) carrier and added to the feeds. The feed was wheat-soy -based starter formula. The dietary treatments:

1. Control, no TOFA soap

2. Control + TOFA soap 0.1% (1 kg/ton)

3. Control + TOFA soap 0.05% (500 g/ton)

4. Control + TOFA soap 0.01% (100 g/ton)

Chicks were weighed on days 1, 11, 14, and

17. Feed consumption was measured and feed conversion ratio (FCR) was calculated for the same periods. Daily mortality was recorded.

After day 17, 105 ileal and 105 cecal digesta samples were analysed for short chain fatty acids (SCFAs) with gas chromatography and a number of microbial species or groups by qPCR.

Results

The results are illustrated in Figures 2a - 2d. Dietary TOFA soap with 5% resin acids, fed at the level of 0.1-1 kg/ton, dose-dependently increased the body weight of broiler chicks on days 8, 11, and 14 (Figure 2a) . FCR was improved by the TOFA soap at 0.1 - 1 kg/ton, either numerically or statistically sig- nificantly (Figure 2b) . TOFA soap at 0.1-1 kg/ton fa ^¬ vourably and dose-dependently modulated the small in ^¬ testinal microbial fermentation from homofermentative to heterofermentative direction (Figure 2c) . Ileal and cecal numbers of CI. perfringens were not significant- ly affected by dietary TOFA amendment. TOFA soap at 0.5 kg/tn decreased the frequency of samples with more than 1*10 ⁹ cells of enterococci or streptococci, or more than 1*10 ¹² cells of lactobacilli . TOFA soap at 1 kg/ton decreased the frequency of samples with high counts of lactobacilli (Figure 2d) .

The results show that the saponified TOFA modulates the microbial population of the digestive tract of broiler chicks or other species of poultry if given in the feed and improve the feed conversion ra ^¬ tio.

It is obvious to a person skilled in the art that, with the advancement of technology, the basic idea of the invention may be implemented in various ways. The invention and its embodiments are thus not limited to the examples described above; instead they may vary within the scope of the claims.