Methods of modifying the tobacco-specific nitrosamine content of a tobacco material are described herein. One exemplary method comprises contacting a tobacco material with a composition comprising salt, sugar, enzyme, lactic acid bacteria, yeast, or a combination thereof to reduce the total bacterial content; curing the tobacco material; and fermenting the tobacco material in the presence of one or more microorganisms. The method can provide a fermented tobacco material having a tobacco-specific nitrosamine content that is reduced relative to a fermented tobacco material that has not been subjected to the disclosed method steps. In certain embodiments, the tobacco-specific nitrosamine content of the fermented tobacco material is no more than that of the cured tobacco material. Tobacco-containing products including such treated tobacco materials are also provided.

Methods and compositions are provided for expressing an endolysin in a bacterium or in a tobacco plant or plant part. Expression of the endolysin can reduce the total bacterial load on the plant and in tobacco products produced from the plant. Accordingly, the level of tobacco specific nitrosamines (TSNA) in a cured tobacco product can be decreased when the tobacco leaves used in the product were harvested from a plant expressing endolysin or when bacteria modified to express endolysin is used to treat the tobacco. Thus, bacteria and tobacco plants and plant parts are provided that express an endolysin. Further provided are methods for decreasing the microbial load on a tobacco plant and in a tobacco product by applying a solution of bacteria modified to express an endolysin or by modifying a tobacco plant to express endolysins. Smokeless tobacco products including such modified tobacco plant parts are also provided.

A method of modifying the content of certain bacteria in uncured tobacco material is provided, the method including contacting an uncured tobacco material with a treatment solution, wherein the treatment solution is selected from the group consisting of: (i) a solution comprising salt, sugar, or a combination thereof; (ii) a solution comprising one or more enzymes; and (iii) a solution comprising one or more probiotics, wherein said contacting provides a treated tobacco material having a reduced total bacterial content following harvest. In certain embodiments, the treated tobacco material is subsequently cured, and can optionally be fermented. Smoking articles and smokeless tobacco products including such treated tobacco materials are also provided.

A method of modifying the content of certain bacteria in uncured tobacco material is provided, the method including contacting an uncured tobacco material with a treatment solution, wherein the treatment solution is selected from the group consisting of: (i) a solution comprising salt, sugar, or a combination thereof; (ii) a solution comprising one or more enzymes; and (iii) a solution comprising one or more probiotics, wherein said contacting provides a treated tobacco material having a reduced total bacterial content following harvest. In certain embodiments, the treated tobacco material is subsequently cured, and can optionally be fermented. Smoking articles and smokeless tobacco products including such treated tobacco materials are also provided.

Methods and compositions are provided for expressing an endolysin in a bacterium or in a tobacco plant or plant part. Expression of the endolysin can reduce the total bacterial load on the plant and in tobacco products produced from the plant. Accordingly, the level of tobacco specific nitrosamines (TSNA) in a cured tobacco product can be decreased when the tobacco leaves used in the product were harvested from a plant expressing endolysin or when bacteria modified to express endolysin is used to treat the tobacco. Thus, bacteria and tobacco plants and plant parts are provided that express an endolysin. Further provided are methods for decreasing the microbial load on a tobacco plant and in a tobacco product by applying a solution of bacteria modified to express an endolysin or by modifying a tobacco plant to express endolysins. Smokeless tobacco products including such modified tobacco plant parts are also provided.

A method of modifying the content of certain chemical compounds in tobacco materials is provided, the method including treatment of a tobacco plant or portion thereof with at least one enzyme. For example, the method may modify the content of tobacco smoke toxicant precursors in tobacco materials, which can result in a modification in toxicant production when the tobacco material is exposed to elevated temperatures. The type of tobacco plant or portion thereof treated according to the invention can be, for example, a tobacco seed, a tobacco seedling, an immature live plant, a mature live plant, a harvested plant, or a plant derivative. Smoking articles and other tobacco products including such enzyme-treated tobacco materials are also provided.

A method for treating tobacco material, the method comprising: providing a tobacco material, fermenting the tobacco material to obtain fermented tobacco material, the fermenting step including: # incubating the tobacco material under anaerobic conditions; # stopping the fermentation when at least one of the following conditions is satisfied: # the content of Lactic Acid is more than 10 times, preferably more than 20 times, more preferably more than 50 times, more preferably more than 70 times, preferably more than 80 times an initial amount of Lactic Acid in the tobacco material, # the content of Reducing Sugars is lower than 0.5, preferably lower than 0.4, more preferably below 0.2, more preferably below 0.1 an initial amount or Reducing Sugars in the tobacco material, # the content of Indole-3 Lactic Acid is more than 5 times, preferably more than 10 times, preferably more than 20 times, an initial amount of Indole-3 Lactic Acid in the tobacco material, # the content of caffeic acid is more than 4 times, preferably more than 10 times, preferably more than 20 times, an initial amount of caffeic acid in the tobacco material. # the content of quinic acid is more than 2 times, preferably more than 4 times, an initial amount of quinic acid in the tobacco material, # the content of asparagine is lower than 0.5, preferably lower than 0.4, preferably lower than 0.3 an initial amount or asparagine in the tobacco material, # the content of Glutamine is lower than 0.5, preferably lower than 0.4 an initial amount or Glutamine in the tobacco material, # the content of L-Ornithine is more than 10 times, preferably more than 20 times, preferably more than 50 times, preferably more than 100 times an initial amount of L-Ornithine in the tobacco material, # the content of L-Leucine is more than 2 times, preferably more than 4 times, an initial amount of L-Leucine in the tobacco material, # the content of L-Lysine is more than 2 times, preferably more than 6 times, an initial amount of L-Lysine in the tobacco material, # the fermentation index is more than 50, preferably more than 100, more preferably more than 250, more preferably more 400, wherein the fermentation index is obtained dividing the ratio between the content of Lactic Acid in the treated tobacco material and the content of Lactic Acid in the non-fermented tobacco material by the ratio between the content of Reducing Sugars in the treated tobacco material and the content of Reducing Sugars in the non-fermented tobacco material.

Compositions configured to interact with organic molecules, and related articles and methods, are generally described.