Methods for plant growth stimulation with fermentation leachates

Abstract

Primary leachate is used as a plant growth stimulant. A fermentation medium is fermented with a microbial culture in a bioreactor to produce a primary leachate comprising microorganisms derived from the microbial culture and/or naturally occurring microorganisms. The primary leachate is isolated from the bioreactor, diluted with water, and used to irrigate plants to reduce bacterial diversity and stimulate beneficial microorganisms in the rhizosphere around the plants. The fermentation medium may be organic waste, preferably food waste. A secondary leachate may also be used as a plant growth stimulant. The primary leachate is used to culture black soldier fly larvae with a substrate in a secondary processing bioreactor under suboptimal culture conditions, thereby producing secondary leachate. Melanin is extracted therefrom by acid precipitation. The secondary leachate is then diluted with water and used to irrigate plants, reducing bacterial diversity and stimulating beneficial microorganisms in the rhizosphere around the plants.

What is claimed is: 
     
         1 . A method of using a primary leachate as a plant growth stimulant comprising the steps of:
 (a) providing a primary processing bioreactor, a fermentation medium and a microbial culture comprising microorganisms of the genera  Clostridium  and  Lactobacillus;      (b) fermenting the fermentation medium with the microbial culture in the primary processing bioreactor, thereby producing a primary leachate, wherein the primary leachate comprises microorganisms derived from the microbial culture and/or naturally occurring microorganisms acquired during the fermentation step;   (c) isolating or removing the primary leachate from the primary processing bioreactor;   (d) diluting the primary leachate with water; and   (e) irrigating plants with the diluted primary leachate, thereby reducing bacterial diversity and stimulating beneficial microorganisms in the rhizosphere around the plants.   
     
     
         2 . The method of  claim 2 , wherein 4 ml of the primary leachate is diluted with one liter of water. 
     
     
         3 . The method of  claim 2 , wherein the fermentation medium is organic waste. 
     
     
         4 . The method of  claim 3 , wherein the organic waste is food waste. 
     
     
         5 . The method of  claim 2 , wherein the beneficial microorganisms are  Pseudomonas putida.    
     
     
         6 . A method of using a secondary leachate as a plant growth stimulant comprising the steps of:
 (a) providing a primary processing bioreactor, a fermentation medium and a microbial culture comprising microorganisms, wherein the microorganisms in the microbial culture comprise microorganisms of the genera  Clostridium  and  Lactobacillus;      (b) fermenting the fermentation medium with the microbial culture in the primary processing bioreactor, thereby producing a primary leachate, wherein the primary leachate comprises microorganisms derived from the microbial culture and/or naturally occurring microorganisms acquired during the fermentation step;   (c) isolating or removing the primary leachate from the primary processing bioreactor;   (d) providing the primary leachate isolated or removed from the primary processing bioreactor, a secondary processing bioreactor,  Hermetia illucens  (black soldier fly) larvae (BSFL), and a cellulose-based substrate;   (e) culturing the BSFL in an aerated culture with the primary leachate isolated or removed from the primary processing bioreactor and the cellulose-based substrate in the secondary processing bioreactor under suboptimal culture conditions for culture of the BSFL, thereby producing a secondary leachate, wherein the suboptimal culture condition is suboptimal temperature, high density, chemical stress, acidification, presence of toxic secondary metabolites, and/or nutrient starvation;   (f) isolating or removing the secondary leachate from the secondary processing bioreactor;   (g) extracting the melanin from the secondary leachate by acid precipitation using an acid other than hydrochloric acid and an alkali other than sodium hydroxide, thereby preventing enrichment of the leachate by chloride and sodium;   (h) diluting the secondary leachate with water; and   (i) irrigating plants with the secondary primary leachate, thereby reducing bacterial diversity and stimulating beneficial microorganisms in the rhizosphere around the plants.   
     
     
         7 . The method of  claim 6 , wherein the fermentation medium is organic waste. 
     
     
         8 . The method of  claim 7 , wherein the organic waste is food waste. 
     
     
         9 . The method of  claim 6 , wherein 4 ml of the secondary leachate is diluted with one liter of water . 
     
     
         10 . The method of  claim 6 , wherein the acid is an organic acid. 
     
     
         11 . The method of  claim 10 , wherein the organic acid is selected from the group consisting of lactic acid, ascorbic acid and citric acid. 
     
     
         11 . The method of  claim 6 , wherein the acid is sulfuric acid. 
     
     
         12 . The method of  claim 6 , where in the alkali is potassium hydroxide. 
     
     
         13 . A method of using a secondary leachate as a plant growth stimulant comprising the steps of:
 (a) providing a primary processing bioreactor, a fermentation medium and a microbial culture comprising microorganisms, wherein the microorganisms in the microbial culture comprise microorganisms of the genera  Clostridium  and  Lactobacillus;      (b) fermenting the fermentation medium with the microbial culture in the primary processing bioreactor, thereby producing a primary leachate, wherein the primary leachate comprises microorganisms derived from the microbial culture and/or naturally occurring microorganisms acquired during the fermentation step;   (c) isolating or removing the primary leachate from the primary processing bioreactor;   (d) providing the primary leachate isolated or removed from the primary processing bioreactor, a secondary processing bioreactor,  Hermetia illucens  (black soldier fly) larvae (BSFL), and a cellulose-based substrate;   (e) culturing the BSFL in an aerated culture with the primary leachate isolated or removed from the primary processing bioreactor and the cellulose-based substrate in the secondary processing bioreactor under suboptimal culture conditions for culture of the BSFL, thereby producing a secondary leachate, wherein the suboptimal culture condition is suboptimal temperature, high density, chemical stress, acidification, presence of toxic secondary metabolites, and/or nutrient starvation;   (f) isolating or removing the secondary leachate from the secondary processing bioreactor;   (g) diluting the secondary leachate with water; and   (h) irrigating plants with the secondary primary leachate, thereby reducing bacterial diversity and stimulating beneficial microorganisms in the rhizosphere around the plants.   
     
     
         14 . The method of  claim 13 , additionally comprising the step of, after isolating or removing the secondary leachate, extracting the melanin from the secondary leachate by acid precipitation using an acid other than hydrochloric acid and an alkali other than sodium hydroxide, thereby preventing enrichment of the leachate by chloride and sodium. 
     
     
         15 . The method of  claim 14 , wherein only large melanin molecules with a molecular weight of greater than 12,000 are extracted from the secondary leachate and the acid precipitation occurs at a pH of between 2 and 5. 
     
     
         16 . The method of  claim 14  wherein very small polyphenols (<8,000 molecular weight) remain in the secondary leachate and the acid precipitation occurs at a pH of between 1 and 2. 
     
     
         17 . The method of  claim 13 , wherein the fermentation medium is organic waste. 
     
     
         18 . The method of  claim 17 , wherein the organic waste is food waste. 
     
     
         19 . The method of  claim 13 , wherein 4 ml of the secondary leachate is diluted with one liter of water. 
     
     
         20 . The method of  claim 13 , wherein the acid is an organic acid. 
     
     
         21 . The method of  claim 20 , wherein the organic acid is selected from the group consisting of lactic acid, ascorbic acid and citric acid. 
     
     
         22 . The method of  claim 13 , wherein the acid is sulfuric acid. 
     
     
         23 . The method of  claim 13 , where in the alkali is potassium hydroxide.