Method for blocking generation of ash hanging smoke by PPO activity inhibitor
By spraying or fumigating tobacco leaves with PPO activity inhibitors such as prothionamide, ruxolitinib or isoliquiritin before baking, the problem of low PPO activity inhibition efficiency is solved, and effective blocking of ash smoke and improvement of tobacco leaf quality are achieved.
Patent Information
- Application Number
- CN202510960465.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-11
- Publication Date
- 2025-09-05
AI Technical Summary
In the existing technology, PPO activity inhibition efficiency is low, environmental adaptability is poor, and safety is insufficient, resulting in serious ash smoke generation, affecting tobacco leaf quality and baking effect.
Before tobacco leaves are cured, PPO activity inhibitors such as prothionamide, ruxolitinib or isoliquiritigenin are used for spraying or fumigation to inhibit the formation of ash smoke by blocking PPO activity.
It effectively blocks the formation of ash smoke, improves the appearance and combustion quality of tobacco leaves, increases the proportion of medium and high-quality tobacco, reduces the risk of chemical residues, and is environmentally friendly and highly safe.
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Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of tobacco, and particularly relates to a method for using a PPO activity inhibitor to block the generation of ash-laden smoke. Background Art
[0002] Ash-stained tobacco is a common type of flue-cured tobacco, accounting for over 30% of all damaged tobacco leaves. It is caused by an enzymatic browning reaction during the flue-curing process. Ash-stained tobacco appears as patches of fine gray or dark brown specks. Internally, it exhibits severe depletion of polyphenols and poorly balanced chemical composition. Overall, it exhibits poor aroma quality, low aroma volume, and an off-flavor. This leads to a sharp decline in tobacco leaf quality and reduced industrial usability, significantly impacting tobacco production.
[0003] PPO (polyphenol oxidase) is a type of enzyme that uses Cu 2+ PPO is an oxidoreductase with a prosthetic group. It is formed during plant tissue development and stored in chloroplasts. Its activity in tobacco leaves has a significant impact on leaf quality and curing performance. In tobacco leaves, PPO catalyzes the oxidation of polyphenols to α-quinone, which then undergoes a browning reaction. α-quinone can then polymerize into melanin, resulting in an excessively dark color. This not only affects the appearance of the leaves but also leads to excessive depletion of internal chemical components, reducing their inherent quality. Therefore, rationally controlling PPO activity in tobacco is crucial for improving leaf quality.
[0004] In practice, PPO activity can be blocked by adding inhibitors. This can reduce the production of gray, black, and variegated smoke, increase the proportion of medium-orange smoke, and enhance the natural characteristic aroma of flue-cured tobacco while reducing irritation. Traditional blocking methods include: chemical inhibitors: These inhibit enzyme activity by chelating the copper ions at the PPO active center. However, these methods pose challenges such as chemical residues and high-temperature inactivation. Repeated additions are costly and can easily cause residual toxicity that affects product safety and flavor. Physical isolation methods: These methods only slow the oxidation process but cannot completely block PPO activity. Gene editing techniques: These methods can knock out the tobacco PPO gene, but face challenges with GMO regulations and public acceptance.
[0005] It can be seen that the core problems of existing technologies are low inhibition efficiency, poor environmental adaptability, and insufficient safety. Therefore, it is urgent to develop efficient, stable and environmentally friendly PPO activity inhibitors. Summary of the Invention
[0006] In response to the above technical problems, the present invention provides a method for blocking the generation of ash smoke by using a PPO activity inhibitor.
[0007] The present invention is achieved through the following technical solutions: A method for blocking the generation of ash smoke using a PPO activity inhibitor, wherein the PPO activity inhibitor is sprayed or fumigated before tobacco leaves are baked to inhibit the activity of PPO and block the generation of ash smoke; The PPO activity inhibitor is any one of Prothionamide, Ruxolitinib, and Isoliquiritigenin.
[0008] Furthermore, when spraying treatment is adopted, deionized water is used to prepare the spraying liquid; The mass percentage concentration of the prepared Prothionamide spray solution is 0.05%~0.1% (w / w), and the spraying volume is 150~300 L / hectare; The mass percentage concentration of the prepared Ruxolitinib spray solution is 0.01%~0.05% (w / w), and the spraying volume is 150~300 L / hectare; The mass percentage concentration of the prepared Isoliquiritigenin spray solution is 0.05%~0.2% (w / w), and the spraying amount is 150~300 L / hectare.
[0009] Furthermore, when spraying treatment is adopted, 1 hour before the tobacco leaves are braided into rods, the tobacco leaves are evenly sprayed with a prothionamide spray solution with a mass percentage concentration of 0.05% to 0.1%, a ruxolitinib spray solution with a mass percentage concentration of 0.01% to 0.05%, or an isoliquiritigenin spray solution with a mass percentage concentration of 0.05% to 0.2%.
[0010] Furthermore, the environmental conditions for spraying are: temperature 25~30℃, relative humidity 60%~70%, avoid direct sunlight and rainfall.
[0011] Furthermore, when fumigation is used, ethyl acetate is used to prepare the fumigant; the concentrations of the prepared prothionamide fumigant, ruxolitinib fumigant and isoliquiritigenin fumigant are 3-5 mmol / L, and the amount of the fumigant used is 150-300 L / hectare.
[0012] Furthermore, when fumigation is used, an electric heating plate is installed in the baking room, and prothionamide fumigant, ruxolitinib fumigant or isoliquiritigenin fumigant is put into an evaporating dish and heated to 75-80°C for 3-5 hours.
[0013] The beneficial technical effects of the present invention are as follows: Ruxolitinib used in the present invention has the highest inhibition efficiency, with a PPO inhibition rate of >90% corresponding to a concentration of 0.01% ruxolitinib, and has a long-lasting effect and good stability. However, there is a risk of aquatic toxicity, and compliance supervision is required when applicable. Isoliquiritigenin used in the present invention has the best environmental adaptability: strong weather resistance, stable pH 4-9, outstanding safety and environmental protection, a 72-hour biodegradation rate of >95%, and is non-toxic to bees. Its inhibition efficiency is second only to that of 0.01% isoliquiritigenin, which has a PPO inhibition rate of 85%. The method provided by the present invention is applied to the production process of tobacco processing, reduces the generation of ash smoke, and improves the appearance and combustion quality of the product. DETAILED DESCRIPTION
[0014] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0015] On the contrary, the present invention covers any alternatives, modifications, equivalents, and solutions that fall within the spirit and scope of the present invention as defined by the claims. Furthermore, to facilitate a better understanding of the present invention, certain specific details are described in detail below in the detailed description of the present invention. Those skilled in the art will be able to fully understand the present invention without these details.
[0016] A survey was conducted to investigate the occurrence of ash-bearing tobacco in a province's major tobacco-growing regions during the field cultivation and curing stages, focusing specifically on the relationship between upper leaf maturity and yellowing and the occurrence of ash-bearing tobacco. The PPO activity inhibitor provided by the present invention was sprayed on braided tobacco leaves before loading them into the curing barn after harvesting, analyzing and verifying the targeted chemical inhibition of the enzymatic browning reaction during the curing process.
[0017] Specifically, tobacco fields with different soil fertility levels, fertilization levels and meteorological conditions in the K326 tobacco area were selected, and the upper tobacco leaves of the same fresh tobacco leaf quality in the same tobacco field were collected, and positioning signs were made.
[0018] A portion of fresh tobacco leaves was photographed to record maturity and appearance, and tested for nitrogen, phosphorus, and potassium nutrient content, cytoplasmic membrane permeability, plastid pigment content, and general chemical composition. Plastid pigment content was characterized by UV spectrophotometry for chlorophyll a, chlorophyll b, carotenoids, and total chlorophyll. General chemical composition was determined by total sugar, reducing sugar, total nitrogen, starch, protein, and nicotine. Antioxidant enzyme activity was determined by polyphenol oxidase and superoxide dismutase. Aroma compounds were characterized by measuring the contents of eight categories: polyphenols, polybasic acids, higher fatty acids, chlorophyll degradation products, carotenoid degradation products, cedarwood degradation products, phenylalanine degradation products, and Maillard reaction products. Economic traits were grouped and graded according to the national standard GB2635-92. Tobacco leaf prices were based on the local price of the year. The yield, average price, output value, and proportion of medium and high-quality tobacco leaves were recorded.
[0019] Another part of fresh tobacco leaves were numbered and cured in the same room. After curing, the fresh tobacco leaves were divided into no ash, light ash, moderate ash and severe ash according to the degree of ash. The quality basis of fresh tobacco leaves with different degrees of ash occurrence was analyzed, and the range of nutritional and physiological characteristic indicators of fresh tobacco leaves with ash occurrence was clarified.
[0020] Baking process monitoring: Dynamic detection of PPO activity, sampling every 12 hours, and determination of PPO activity.
[0021] After the baking is completed, the freshly baked tobacco leaves are divided into no ash, light ash, moderate ash and severe ash according to the degree of ash.
[0022] Ash smoke classification standard, using visual classification: No ash (level 0): There is no ash spot on the tobacco leaf surface; Mild dusting (level 1): the area of dust spots is ≤10%; Moderate dusting (level 2): dust spots cover 10% to 30% of the area; Severe dusting (Level 3): The area of dust spots is >30%.
[0023] Statistics of economic traits: Yield and output value were graded according to the national standard GB 2635-92. The proportion of medium and high-quality tobacco and the average price (yuan / kg) of each group were recorded, and the output value was calculated (yield × average price).
[0024] By observing the color changes and enzyme activity during tobacco leaf curing, the treatment effect of PPO active substances was evaluated, and the enzymatic browning reaction during tobacco leaf curing was monitored. Through repeated experiments and timely adjustments to the strategy, the optimal solution was finally found: A method for blocking the generation of ash smoke by using a PPO activity inhibitor includes spraying or fumigating tobacco leaves with a PPO activity inhibitor before baking to inhibit the activity of PPO and block the generation of ash smoke. The PPO activity inhibitor is any one of Prothionamide, Ruxolitinib, and Isoliquiritigenin.
[0025] When spraying treatment is used, deionized water is used to prepare the spray solution; The mass percentage concentration of the prepared Prothionamide spray solution is 0.05%~0.1% (w / w), and the spraying volume is 150~300 L / hectare; The mass percentage concentration of the prepared Ruxolitinib spray solution is 0.01%~0.05% (w / w), and the spraying volume is 150~300 L / hectare; The mass percentage concentration of the prepared Isoliquiritigenin spray solution is 0.05%~0.2% (w / w), and the spraying amount is 150~300 L / hectare.
[0026] When spraying treatment is used, one hour before the tobacco leaves are braided into rods, the tobacco leaves are evenly sprayed with a prothionamide spray solution with a mass percentage concentration of 0.05% to 0.1%, a ruxolitinib spray solution with a mass percentage concentration of 0.01% to 0.05%, or an isoliquiritigenin spray solution with a mass percentage concentration of 0.05% to 0.2%.
[0027] The environmental conditions for spraying are: temperature 25~30℃, relative humidity 60%~70%, avoid direct sunlight and rainfall.
[0028] When fumigation is used, ethyl acetate is used to prepare the fumigant; the concentration of prothionamide, ruxolitinib, and isoliquiritigenin is 4 mmol / L. The prepared fumigant must be sealed and stored away from light. Ethyl acetate is used as a low-boiling-point solvent (boiling point 76.5°C-77.5°C) to dissolve the three types of PPO activity inhibitors. Avoid open flames and heat the ethyl acetate to its boiling point to volatilize the PPO activity inhibitors within the curing room, achieving a fumigation effect.
[0029] In this embodiment, when fumigation treatment is used, an electric heating plate (power 500 W) is installed in the baking room, and prothionamide fumigant, ruxolitinib fumigant, or isoliquiritigenin fumigant is placed in an evaporating dish (volume 200 mL) and heated to 75-80° C. for 3-5 hours.
[0030] As shown in Tables 1-3: Isoliquiritigenin (0.2%) performed best under both spraying (68.9%) and fumigation (70.5%), and the data stability was strong (standard deviation ≤ 1.7). The inhibition rates of all inhibitors in the fumigation group were significantly higher than those in the spraying group (P < 0.05), among which ruxolitinib (0.01%) had the largest increase (14.8%).
[0031] Table 1: Horizontal comparison of inhibition efficiency As shown in Table 2: Isoliquiritigenin has the strongest comprehensive dust control ability: the proportion of no dusting is the highest (53.8%), and the proportion of moderate to severe dusting is the lowest (18.7%).
[0032] Table 2: Comparison of ash level control effects As shown in Table 3: The proportion of medium and high-quality cigarettes: Isoliquiritigenin (82.4%) > Prothionamide (78.6%) > Ruxolitinib (71.2%) > Control (52.3%). Isoliquiritigenin significantly increased the proportion of medium and high-quality cigarettes to 82.4% (an increase of 57.6% compared with the control), effectively reducing the degradation caused by ash.
[0033] Table 3: Comparison of core indicators This invention, for the first time, utilizes low-boiling-point PPO inhibitors (prothionamide, ruxolitinib, and isoliquiritigenin) for spraying or fumigation before tobacco leaves are cured to preemptively inhibit PPO activity and prevent enzymatic browning reactions throughout the curing process. Curing experiments examining the effects of different low-boiling-point PPO inhibitors on upper leaf curing characteristics and the occurrence of ash smoke reveal the key role of PPO inhibitors in pigment transformation, dynamic water migration, stress resistance of the reactive oxygen system, and changes in PPO activity. Through multi-pathway collaboration, the inhibitors transform enzymatic browning of tobacco leaves into a color transformation driven by the non-enzymatic Maillard reaction, simultaneously optimizing both visual quality and intrinsic physicochemical stability, providing a core biochemical foundation for ash smoke prevention and control. The invention also reveals a targeted chemical blocking mechanism for PPO inhibitors against ash smoke formation, establishing a practical production technology for PPO inhibitors to block PPO activity and reduce ash smoke production.
[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A method for blocking the generation of hanging smoke using a PPO activity inhibitor, characterized in that: Before tobacco leaves are cured, PPO activity inhibitors are sprayed or fumigated to inhibit PPO activity and block the formation of ash smoke. The PPO activity inhibitor is any one of Prothionamide, Ruxolitinib, and Isoliquiritigenin.
2. The method for blocking the generation of ash smoke by using a PPO activity inhibitor according to claim 1, characterized in that: When spraying treatment is used, deionized water is used to prepare the spray solution; The mass percentage concentration of the prepared Prothionamide spray solution is 0.05%~0.1%, and the spraying amount is 150~300 L / hectare; The mass percentage concentration of the prepared Ruxolitinib spray solution is 0.01%~0.05%, and the spraying volume is 150~300 L / hectare; The mass percentage concentration of the prepared Isoliquiritigenin spray solution is 0.05%~0.2%, and the spraying amount is 150~300L / hectare.
3. The method for blocking the generation of ash smoke by using a PPO activity inhibitor according to claim 1, characterized in that: When spraying treatment is used, one hour before the tobacco leaves are braided into rods, the tobacco leaves are evenly sprayed with a prothionamide spray solution with a mass percentage concentration of 0.05% to 0.1%, a ruxolitinib spray solution with a mass percentage concentration of 0.01% to 0.05%, or an isoliquiritigenin spray solution with a mass percentage concentration of 0.05% to 0.2%.
4. The method for blocking the generation of ash smoke by using a PPO activity inhibitor according to claim 3, characterized in that: The environmental conditions for spraying are: temperature 25~30℃, relative humidity 60%~70%, avoid direct sunlight and rainfall.
5. The method for blocking the generation of ash smoke by using a PPO activity inhibitor according to claim 1, characterized in that: When fumigation is used, ethyl acetate is used to prepare the fumigant; the concentration of the prepared prothionamide fumigant, ruxolitinib fumigant and isoliquiritigenin fumigant is 3~5mmol / L, and the fumigant usage is 150~300 L / hectare.
6. The method for blocking the generation of ash smoke by using a PPO activity inhibitor according to claim 5, characterized in that: When fumigation is used, an electric heating plate is installed in the baking room, and prothionamide fumigant, ruxolitinib fumigant or isoliquiritigenin fumigant is placed in the evaporating dish and heated to 75-80°C for 3-5 hours.