Bio-enriched soil technologies (BEST)
12052953 ยท 2024-08-06
Assignee
Inventors
Cpc classification
A01G24/00
HUMAN NECESSITIES
C09K17/50
CHEMISTRY; METALLURGY
International classification
A01G24/00
HUMAN NECESSITIES
Abstract
A bio-enriched soil and method of production is presented. If water supply is scant, bio-enriched soil technologies (BEST) are able to attract, store, and transport water and nutrient molecules to a plant in a controlled way. If the water or nutrient resources are excessive, BEST can release the excess and supply only what is needed. Hence, bio-enriched soil can function in climates in which crops normally are under stress by increasing the bioavailability of nutrients and water.
Claims
1. A method of enhancing soil by modulating water and nutrient availability in the soil comprising: measuring moisture in the soil to determine soil water balance; measuring a surface tension of the soil and decreasing the surface tension of the soil to below about 72 mN/m if the surface tension of the soil as measured is equal to or above 72 mN/m; modeling soil environment using a COMSOL? model to determine changes in the soil water balance in response to adding cactus mucilage to the soil; adding an amount of cactus mucilage to the soil based on results obtained in the COMSOL model; and subsequently adding an amount of at least one inorganic compound to the soil to produce a bio-enriched soil.
2. The method of claim 1, wherein the at least one inorganic compound is at least one macronutrient, at least one micronutrient, or combinations thereof.
3. The method of claim 1, wherein the cactus mucilage is obtained from Opuntia ficus indica (OFI).
4. The method of claim 1, wherein the cactus mucilage is present in the bio-enriched soil in a random configuration.
5. The method of claim 1, wherein the cactus mucilage is present in the bio-enriched soil in a linear or a three-dimensional (3D) configuration.
6. A method of modulating water and nutrient availability in soil comprising: measuring moisture in the soil to determine soil water balance; measuring a surface tension of the soil and decreasing the surface tension of the soil to below about 72 mN/m if the surface tension of the soil as measured is equal to or above 72 mN/m; modeling soil environment using a COMSOL? model to determine changes in the soil water balance in response to adding cactus mucilage to the soil; adding an amount of cactus mucilage to the soil based on results obtained in the COMSOL model; and subsequently adding at least one nutrient to the soil to produce a bio-enriched soil; wherein the cactus mucilage stores or releases the water and the at least one nutrient in response to soil conditions.
7. The method of claim 6, wherein the cactus mucilage is obtained from Opuntia ficus indica (OFI).
8. The method of claim 6, wherein the cactus mucilage is present in the bio-enriched soil in a linear configuration.
9. The method of claim 6, wherein the cactus mucilage is present in the bio-enriched soil in a random configuration.
10. The method of claim 6, wherein the cactus mucilage is present in the bio-enriched soil in a three-dimensional (3D) configuration.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) For a fuller understanding of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which:
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
(13) In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings, which form a part hereof, and within which are shown by way of illustration specific embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized, and structural changes may be made without departing from the scope of the invention.
Definitions
(14) Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, some potential and preferred methods and materials are described herein. All publications mentioned herein are incorporated herein by reference in their entirety to disclose and describe the methods and/or materials in connection with which the publications are cited. It is understood that the present disclosure supercedes any disclosure of an incorporated publication to the extent there is a contradiction.
(15) As used herein, the term comprising is intended to mean that the products, compositions and methods include the referenced components or steps, but not excluding others. Consisting essentially of when used to define products, compositions and methods, shall mean excluding other components or steps of any essential significance. Consisting of shall mean excluding more than trace elements of other components or steps.
(16) As used in the specification and claims, the singular form a, an and the include plural references unless the context clearly dictates otherwise.
(17) All numerical designations, such as pH, temperature, time, concentration, and molecular weight, including ranges, are approximations which are varied up or down by increments of 1.0 or 0.1, as appropriate. It is to be understood, even if it is not always explicitly stated that all numerical designations are preceded by the term about. It is also to be understood, even if it is not always explicitly stated, that the reagents described herein are merely exemplary and that equivalents of such are known in the art and can be substituted for the reagents explicitly stated herein.
(18) Concentrations, amounts, and other numerical data may be expressed or presented herein in a range format. It is to be understood that such a range format is used merely for convenience and brevity and thus should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. As an illustration, a numerical range of about 1 to about 5 should be interpreted to include not only the explicitly recited values of about 1 to about 5, but also include the individual values and sub-ranges within the indicated range, to the tenth of the unit. Thus, included in this numerical range are individual values such as 2, 3, and 4 and sub-ranges such as from 1-3, from 2-4 and from 3-5, etc. This same principle applies to ranges reciting only one numerical value. Furthermore, such an interpretation should apply regardless of the range or the characteristics being described.
(19) All numerical designations, including ranges, are approximations which are varied up or down by increments of 1.0, 0.1 or 0.01, as appropriate. It is to be understood, even if it is not always explicitly stated that all numerical designations are preceded by the term about. It is also to be understood, even if it is not always explicitly stated, that the reagents described herein are merely exemplary and that equivalents of such are known in the art and can be substituted for the reagents explicitly stated herein.
(20) The term about or approximately as used herein refers to being within an acceptable error range for the particular value as determined by one of ordinary skill in the art, which will depend in part on how the value is measured or determined, i.e. the limitations of the measurement system, i.e. the degree of precision required for a particular purpose. As used herein about refers to +10%.
(21) Optional or optionally means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.
(22) As used herein, plant mucilage refers to a substance of polar glycoprotein, which may be extracted from the tissue and/or seeds of various plants such as the plants of the Cactaceae family. In some embodiments, the mucilage is obtained from the Opuntia spp such as Opuntia ficus-indica and Opuntia cochenillifera.
(23) Sustainable soil systems (S.sup.3) or bio-enriched soil technologies (BEST) as used herein refer to a system using bio-enriched soil to modulate bioavailability and use of water, macronutrients, micronutrients, or a combination thereof by plants to contribute to a more sustainable agriculture by making fertilizer and water use more efficient and cost-effective. Sustainable soil systems and bio-enriched soil technologies are used interchangeably herein.
(24) Soil as used herein refers to the upper layer of earth in which plants grow which is generally comprised of unconsolidated minerals, water, gas, and organic material. Soil as used herein includes the A horizon (topsoil), the B horizon (subsoil) and the O horizon (organic), if present. Ideal soil for plant growth contains 50% pore space and 50% solids, with the pore space filled with equal parts water and air. Of the 50% solids, the ideal ratio is 45% mineral matter and 5% organic matter.
(25) Bio-enriched soil as used herein refers to soil to which an amount of mucilage from the plants of the Cactaceae family has been added. Bio-enriched soil may also include at least one nutrient.
(26) Three-dimensional (3D) configuration as used herein refers to a mucilage, or optionally a mucilage and nutrient (macro-, micro-, or a combination thereof) mixture, arranged in soil in a series of horizontal rows and vertical columns to produce a bio-enriched soil.
(27) Macronutrient as used herein refers to elements used by plants in large amounts for plant growth and seed production. Exemplary macronutrients include, but are not limited to, carbon (C); hydrogen (H); oxygen (O); nitrogen (N); phosphorus (P); potassium (K); calcium (Ca); magnesium (Mg); sulfur (S); and combinations thereof. The macronutrients of C, O, and H are normally supplied to the plant by air and water. In some embodiments, individual ions of the macronutrients are used. In other embodiments, ionic compounds are used. Exemplary ionic compounds include, but are not limited to, ammonium nitrate; ammonium sulfate; calcium phosphate; and calcium sulfate.
(28) Micronutrient as used herein refers to elements used by plants in small amounts for plant growth and seed production. Exemplary micronutrients include, but are not limited to, chlorine (Cl); iron (Fe); boron (B); manganese (Mn); zinc (Zn); copper (Cu); molybdenum (Mb); nickel (Ni); cobalt (Co); sodium (Na); silicon (Si); and combinations thereof. A balance of macronutrients and micronutrients is needed for healthy plant growth.
(29) Nutrient as used herein refers to a substance used by plants to aid in growth and fertility. Nutrients include macronutrients, micronutrients, or combinations thereof.
(30) Inorganic compound as used herein refers to a compound that does not contain carbon and is not a part of, or produced by, a living organism. Mineral elements are considered inorganic compounds. Inorganic compound and inorganic molecule are used interchangeably herein.
(31) Organic molecule as used herein refers to a compound that contains carbon or is directly produced by a living organism. Organic compound and organic molecule are used interchangeably herein.
(32) Fertilizer as used herein refers to a natural or synthetic substance that contains chemical elements and is added to soil to assist in plant growth and fertility. Both organic and inorganic fertilizers are contemplated, depending on the needs of the plants and soil. Organic fertilizers are derived directly from plant or animal sources while inorganic fertilizers are synthetic in that they typically undergo a manufacturing process. Inorganic fertilizers are in a form that is readily available for plant use while organic fertilizers may require conversion to an inorganic form by bacteria or fungi before the plant can use them.
(33) Pesticide as used herein refers to a chemical substance or mixture intended to prevent, destroy, repel, control or mitigate any organism harmful to a plant. Pesticides include, but are not limited to, herbicides; insecticides; fungicides; disinfectants; compounds for controlling vermin such as rats and mice; and combinations thereof.
(34) The main component of bio-enriched soil technologies (BEST) or sustainable soil systems (S.sup.3) is cactus mucilage, the part of the cacti that is responsible for storing and transporting water and nutrients through the plant's capillaries. BEST is capable of enhancing food and energy crop productivity in a variety of climates and soil types through functionalizing the cactus mucilage with inorganic molecules, such as single ions or ionic compounds, and blending it into the soil to manage plant nutrient and water bioavailability through functionalized natural materials acting as sensors in the topsoil. Exemplary ions and ionic compounds useful herein include, but are not limited to, ions containing nitrogen (N), phosphorus (P) and potassium (K), calcium (Ca), magnesium (Mg) and sulfur (S) and their ionic compounds including, but not limited to, ammonium sulfate, ammonium nitrate, calcium phosphate and calcium sulfate. The inventor has previously shown that cactus mucilage is capable of purifying water by binding ions such as arsenic. (U.S. Pat. Nos. 7,943,049 and 9,776,895; Fox, D. et al., Removing heavy metals in water: the interaction of cactus mucilage and arsenate (As(V)), Environmental Science and Technology, 2012, 46(8):4553-4559, each of which is incorporated herein by reference).
(35) The soil's physical and chemical properties, such as pH, alkalinity and salinity as well as its nutrient content often are the rate-limiting factors in commercial crops. Exemplary functionalized natural materials capable of acting as sensors include, but are not limited to, a system-like paper capable of capturing the pH and ionic strength of the soil which shows a change of color in response to the differences in ionic conditions. Sustainable soil systems are customized by integrating feedback and system thinking of the social, behavioral and economic sciences.
(36) The following non-limiting examples illustrate exemplary systems and components thereof in accordance with various embodiments of the disclosure. The examples are merely illustrative and are not intended to limit the disclosure in any way.
Example 1Bio-Enriched Soil
(37) Developed functional cacti mucilage networks can produce a potentially superior soil capable of retaining and providing nutrients and water efficiently. Cactus mucilage from the Opuntia ficus indica (OFI) is an FDA-approved compound that is non-toxic (100% edible). This type of compound is already used in FDA-approved drugs (NDC Codes: 59535-0131-1, 59535-1311-1, 15631-0322-0, 15631-0322-1, 15631-0322-2, 15631-0322-3). (National Library of Medicine 2016).
(38) If water supply is scant, sustainable soil systems (S.sup.3) can attract, store, and transport water and nutrient molecules to a plant in a controlled manner. If the water or nutrient resources are excessive, S.sup.3 can release the excess and supply only what is needed. Hence, S.sup.3 soil can function in climates in which crops normally are under stress by increasing the bioavailability of nutrients and water. Cactus mucilage's natural ability to bind and release individual macronutrients, micronutrients and water can greatly contribute to a more sustainable agriculture by making fertilizer and water use more efficient and cost-effective.
(39) Surface Tension
(40) The preliminary data show that the surface tension (ST) is a parameter of interest to determine the ability of cactus mucilage to easily transport organic and inorganic nutrients, herbicides, or fertilizers. (Knoche 1994). The dimensions of ST are force per unit length. If ST values are lower than that of water (reference value: 72 mN/m at standard operating conditions), the system is capable of transporting compounds in liquid or solid environments.
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(42) Osmotic Mobility
(43) Similarly, the inventors have also monitored the behavior of the osmotic mobility effectiveness of cactus mucilage as a function of osmotic power (OP). OP is reported in terms of practical salinity units (PSU). Also known as salinity gradient power or blue energy, OP is the energy available from the gradients in salinity between two media. (Loeb 1975). The inventors measured the osmotic mobility effectiveness of cactus mucilage as a function of concentration for two osmotic powers (
(44) Mucilage Interactions
(45) The inventors have also studied the interactions of mucilage with metals and found a significant binding with K, Fe, and Ca. (Stebbins 2013). These results indicate that the inventors are able to design and monitor how cactus mucilage promotes the mobility of nutrients, pesticides, and fertilizers depending on soil quality. Mucilage is a combination of polysaccharides. As such, mucilage is capable of transporting water via capillary forces back and forth depending on the pressure difference.
(46) Cacti have been instrumental in providing clues about CAM (Crassulacean acid metabolism), which is when net CO.sub.2 uptake for plant photosynthesis occurs at night with minimum water loss. (Nobel 1991). Learning from and emulating how a cactus plant efficiently allocates and provides water and nutrients through S.sup.3 elucidates other biological processes involved in plant growth and survival.
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(48) The water transport in the mucilage is like pulling a string (cohesive water movement depends on capillary and intermolecular forces) through a long, narrow tubular straw. The structure of the mucilage facilitates the water movement by creating a difference in the osmotic pressure between its chains. Water transport is quantified by the radial and axial volume of water that moves across the cactus mucilage surface area due to a pressure gradient per unit time, also known as hydraulic conductivity or Lp. Reported values for OFI cactus (prickly pear cactus or nopal) range from 1.45+0.15 x10-7 ms-1 MPa.sup.?1 depending on soil wettability. (Lopez 1991). This is also a measure of the energy per unit time (Joule/s) that drives water and ion movement in the radial and lateral directions and an estimate for the short-term intermolecular interactions between mucilage and water molecules. The Lp for OFI is extremely stable even though the soil water levels may be considerably different. For instance, Nobel and North (1994, 1996) reported that tissues of OFI displayed Lp values of 1.3-1.44?10.sup.?7 ms-1 MPa.sup.?1 for 3-month-old roots in 1-30 days of exposure to wet, drying, and rewetted soils. (North 1992). They also studied the ability of OFI to come back after being in draught conditions and observed that OFI tissues recovered 90% of their maximum Lp after only 7 days of being exposed to rewetted soil. (North 1996).
(49) In the OFI cactus plant, once the water arrives to the inner cortex, it is stored by cactus mucilage (
(50) OFI is a succulent that exhibits a greater capacity for water storage and has the ability to withstand a high degree of dehydration without irreversible damage. (Nobel 2002). It also has the greatest net CO.sub.2 uptake rate and total daily net CO.sub.2 uptake of succulents because of the water stored in its cladodes (18 ?mol m.sup.?2 s.sup.?1) and a high water-use efficiency of the CAM pathway (698 mmol m.sup.?2 day.sup.?1). (Cui 1994). In addition, OFI is the most widely-cultivated succulent worldwide and the best-studied species with respect to root development and structure. (Young 2006; Nobel 2002). The inventors have studied the macroscopic performance of OFI mucilage for its flocculation and surface active properties to remove contaminants from water for more than 12 years. (Young 2005; Young 2006). Contrary to slow-growing cacti, such as the Saguaro species (Carnegiea gigantea), OFI grows abundantly, even in arid environments. It has been reported that dry weight production of OFI between 20,000-50,000 kg/ha/yr (1 ha=10,000 m.sup.2) is typical in a cactus farm. (Nobel 1987).
(51) A potential additional benefit is cactus mucilage's ability (based on the preliminary results) to bind organic compounds, which could serve the farmer's needs far more efficiently in administering pest control agents. (Buttice 2014; Fox 2016; Vecino 2016). Such chemicals are expected to bind to the mucilage in the soil, preventing washout by rainwater and hence becoming bioaccessible to crops for a more sustainable use of pesticides and insecticides that deliver maximum value to farmers while preventing pollution of the environment.
(52) The inventors target food and energy crops, thus aiming at improving food and bioenergy productivity in a more sustainable society. This reduces the cost of crop production for food and energy applications and will improve profit margins of small farmers in particular. The socio-economic and geographic forces that drive susceptibility and acceptability are a critical part of the project for learning how to implement such systems.
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Example 2Simulation Model of Soil Water Balance with Mucilage Addition
(54) COMSOL is one of the best-known multi-physics models. COMSOL simulates different geophysical conditions by element analysis and partial differential equations. This example models the soil water balance and tracks a solute in groundwater flow for 1000 days to determine the transport and absorption of water with an emphasis on the mucilage. A powder represents the mucilage in the simulation to estimate how the soil water system changes in response to the addition of the mucilage.
(55) Richards' equation, a nonlinear partial differential equation used to represent the movement of water in unsaturated soil, was used to calculate the absorption of water by the soil. The simulated model covered a square area of 4?4 Km.sup.2.
Results
(56) The simulated system was used to demonstrate whether or not the added mucilage assists the plant in absorbing water. An arrow surface plot was created which displays the flow of water within the soil after 1000 days. (
(57) The COMSOL simulation included designing a transport system in porous media and calculating the water flow over a specified period of time. The simulation results matched the analytical solution. The results show that the seeds absorb their own share of water while in the soil.
(58) The mucilage of the plant simulated was represented by powder at the center of the system. According to the simulation, the mucilage captures the water and stores it, which causes a slow reduction of the water in the soil over time. After the soil dries, water in the mucilage diffuses back to the soil, affecting the land or the plant root within the system, to allow the soil to become more humid again. As such, mucilage contributes to the storage of water within the plant.
Methods
(59) The COMSOL software was used to model the soil water balance in a simulation and a solute was tracked for 1000 days to determine the transport and absorption of water and the affect of mucilage on water absorption.
(60) Briefly, a transportation library file was created in which a 2D square was added as an object. The square was positioned in the center with a given length L. Physics was added to the application and the transport method was optimized to be Transport of a Diluted Species in Porous Media (TDS). A no-flux boundary condition was created. No-flux boundary is defined as there being zero flux in boundary nodes which allows for the velocity fluxes to only be calculated after completing the process, as in after Richards' equation is solved, as the hydraulic conductivity multiplied by the pressure head gradient averaged over the element containing a particular boundary node. (Neph 2008).
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(62) where h is the elevation induced by capillary action; x is the elevation; K is the hydraulic conductivity; and q is the volumetric flow rate (water). Inflow and outflow boundaries are set with inflow boundaries set between 1 and 3 and outflow boundaries set between 2 and 4. This allowed for all transport parameters to be efficiently optimized.
(63) Equation (2) below was inserted into the simulation in the Expression field:
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(65) where x and y are metric dimensions for the size of the system. The whole term describes the moisture content, i.e. this is the solution for when water saturation is achieved. The arguments of the function were labeled as x and y. in the Units section, the arguments were m and the function was 1. Plot parameters for x and y have a lower limit of ?2000 and an upper limit of 2000.
(66) To simulate the physics of the system, initial values of TDS were accessed as units of 1 mol/m.sup.3. Additional variables were defined such as name (c_analytic); expression (an1(x,y,t)); unit (mol/m.sup.3); and description (analytic solution). The structure also required adjusting the size and inserting a mesh. The mesh was beneficial to resolve spatial distribution. Finer mesh of a high quality is preferred.
(67) The model was built on the idea of simulating the system for 1000 days thus it must be time dependent. Inclusion of a restricted maximum time step increases the accuracy. In this system, the maximum step constraint was labeled as constant with the maximum step being 20.
Conclusion
(68) The simulation illustrated that mucilage is capable of contributing to the storage of water within the plant and seeds absorb their own share of water when in the soil. The addition of mucilage to soil can assist in attracting, storing, and transporting water and nutrient molecules to a plant in a controlled manner.
Example 3Linear Mucilage Configuration in Bio-Enriched Soil (Prophetic)
(69) Cactus mucilage's natural ability to bind and release individual macronutrients, micronutrients and water can greatly contribute to a more sustainable agriculture by making fertilizer and water use more efficient and cost-effective.
(70) A composition of cactus mucilage may be used which includes both gelling extract (GE) and non-gelling extract (NE) combined or alternatively, either GE or NE may be used individually.
(71) Cactus mucilage can be extracted by various methods. The most common method uses water as a solvent for maceration, followed by a filtration process and precipitation. Other methods include use of a mechanical press with or without subsequent precipitation. Methods for extracting mucilage are known in the art as described in Gheribi et al., herein incorporated by reference into this disclosure. (Ghiribi, R. et al., 2019, Cactus mucilage for food packaging applications, Coatings, 9:655).
(72) Extraction of Mucilage (First Method)
(73) In an embodiment, mucilage is extracted from fresh cactus pads. The pads are washed, dried and weighed. The pads are diced or peeled and boiled for 20 min, then the mixture is liquidized in a blender. 1M sodium hydroxide (NaOH) is added to neutralize the mixture and then centrifuged to separate the supernatant (which contains the NE) from the solid precipitate (containing the GE). Before the GE is extracted, the non-gelling extract (NE) is removed. The GE is then extracted using an adaptation of a method developed by Turquois et al. (Turquois, et al. Extraction of highly gelling pectic substances from sugar beet pulp and potato pulp: influence of extrinsic parameters on their gelling properties. Food Hydrocolloids 1999, 13, (3), 255-262). The solids are mixed with 7.5 g/L sodium hexametaphosphate [(NaPO.sub.3).sub.6] in 50 mM NaOH, in a 1:1 mass-to-volume ratio of solids to solution. The mixture is stirred for 1 h, then vacuum filtered with knitted polyester cloth or Whatman 41 filter paper to obtain the filtrate. The filtrate pH is lowered to 2 using hydrochloric acid (HCl) and refrigerated overnight (? 5? C.) in order to precipitate the GE. The precipitate is separated by centrifugation, re-suspended in sufficient deionized (DI) water to cover the pellet, and the pH is adjusted to 8.0 with 1M NaOH to re-dissolve the precipitate. The resulting solution is purified by successive filtering through a 1.2 ?m and a 0.45 ?m membrane. The GE is re-precipitated with acetone or isopropanol in a 2:3 liquid-to-solvent volume-to-volume ratio, then is washed with alcohol and dried under ambient conditions.
(74) The non-gelling extract (NE) is collected as described above, and sodium chloride is added to the supernatant to form a final concentration of 1M NaCl. The supernatant is filtered with knitted polyester cloth or Whatman 41 filter paper, based on the viscosity of the liquid, to obtain the filtrate. Acetone or isopropanol is added in a 2:3 volume-to-volume ratio of supernatant to solvent to precipitate the NE. The precipitate is washed with ethanol-water mixtures in a graded series (70%, 80%, 90%, 95% ethanol, and absolute ethanol) to remove any remaining impurities. The precipitate is left to dry at room temperature overnight, followed by an overnight drying in an air oven.
(75) Extraction of Mucilage (Second Method)
(76) In another embodiment, mucilage is alternatively extracted from fresh cactus pads as NE in which the cactus pads are washed, dried, weighed, and subsequently cut longitudinally in halves. The parenchyma (white fleshy inside) of the pads is scooped out with a spoon and pressed through a potato press to crush the parenchyma and break the mucilaginous cells thereby releasing the mucilage. Alternatively, the crushing of mucilaginous cells may be achieved with other tools, such as crushing the material with a stone or mortar and pestle.
(77) The pressed liquid is collected, and the solids are discarded. Isopropanol is added to the liquid in a volume-to-volume ratio of 3:2 alcohol to liquid to precipitate the mucilage. The precipitate is washed with three 5 mL to 10 mL aliquots of isopropanol. The precipitate is placed on a petri dish to dry overnight and subsequently is oven dried at 50? C. overnight. The dry precipitate is then pulverized with a mortar and pestle and stored in an airtight plastic vial.
(78) Extraction of Mucilage (Third Method)
(79) In a further embodiment, cactus pads are washed, dried, weighed and diced into approximately 1 cm cubes. The cactus cubes are then immersed in 1% sodium chloride solution in a 1:1 mass to volume ratio. Liquid is added to the material until the solution covered the diced cactus. The mixture is boiled for 15 minutes then cooled. The liquid and solids are squeezed through a potato press and the liquid is retained while the residual solids are discarded. Isopropanol is added to the liquid in a 3:2 alcohol to liquid volume-to-volume ratio to precipitate the mucilage. The precipitate is washed with three 5 to 10 mL aliquots of isopropanol. The precipitate is placed on a petri dish to dry overnight then it is oven dried at 50? C. overnight. The dry precipitate is then pulverized with a mortar and pestle and stored in an airtight plastic vial.
(80) Extraction of Mucilage (Fourth Method)
(81) In a further embodiment, for the extraction of nongelling extract (NE) and gelling extract (GE), cactus pads are cleaned and boiled in milli Q water until they become tender (approximately 20 minutes). The soft pads are then liquefied in a blender. The pH of the resulting suspension is then neutralized and the solids and liquid supernatant are separated in a centrifuge at 4000 rpm. The supernatant is collected, mixed with 1M-NaCl solution (10:1 ratio), filtered and precipitated with 1:2 ratio of pulp to acetone to produce the NE extract. The acetone is then decanted and the precipitate washed with a 1:1 volume ratio of precipitate to isopropanol. The resulting NE precipitate is air dried on a watch glass at room temperature.
(82) In order to separate the gelling portion, the centrifuged precipitates are mixed with 50 mL of 50 mM NaOH. The suspension is stirred for 10 min and the pH adjusted with HCl to 2. The suspension is centrifuged and the solids again resuspended in water while the pH is adjusted to 8 with NaOH. The suspension is then filtered and the solids are washed following the same procedure as for the NE extract.
(83) For the combined extract, the initial blend is centrifuged and the supernatant is separated and pH adjusted to 8 with NaOH, washed with acetone and isopropanol as described above and finally it is air-dried. On average, for each pad that weighs around 300 g wet weight, a 1.5-2 g dry powder is obtained.
(84) Use of Mucilage in Linear Configuration
(85) The mucilage obtained by any of the described methods of extraction is blended into the soil. For a linear configuration, the mucilage may be added to the soil in a linear configuration (either vertical, diagonal, or horizontal lines), for example by injection of the mucilage into the soil. In the embodiment where the lines are horizontal, this may also be referred to as a layered configuration in which a horizontal layer of mucilage separates layers of soil.
(86) The mucilage may be mixed with inorganic or organic compounds such as nutrients or ions/ionic compounds prior to being blended with the soil. Alternatively, inorganic or organic compounds can be added to the soil after incorporation of the mucilage. Alternatively, the nutrients or ion/ionic compounds can be present in the soil prior to mixing in the mucilage. In some embodiments, the nutrients are added to the water that is added to the system. The nutrients are transported along with the water molecules in all embodiments. Nonlimiting examples of inorganic and organic compounds include, but are not limited to, ions, macronutrients, micronutrients, fertilizers, pesticides and insecticides.
(87) The interactions of mucilage with soil compounds is optimized and finely-controlled depending on the carrier volume and cactus mucilage concentration.
Example 4Random Mucilage Configuration in Bio-Enriched Soil (Prophetic)
(88) Cactus mucilage's natural ability to bind and release individual macronutrients, micronutrients and water can greatly contribute to a more sustainable agriculture by making fertilizer and water use more efficient and cost-effective.
(89) A composition of cactus mucilage may be used which includes both gelling extract (GE) and non-gelling extract (NE) or alternatively, either GE or NE may be used individually.
(90) Cactus mucilage can be extracted by various methods. The most common method uses water as a solvent for maceration, followed by a filtration process and precipitation. Other methods include use of a mechanical press with or without subsequent precipitation. Methods for extracting mucilage are known in the art as described in Gheribi et al., herein incorporated by reference into this disclosure. (Ghiribi, R. et al., 2019, Cactus mucilage for food packaging applications, Coatings, 9:655).
(91) Extraction of Mucilage (First Method)
(92) In an embodiment, mucilage is extracted from fresh cactus pads. The pads are washed, dried and weighed. The pads are diced or peeled and boiled for 20 min, then the mixture is liquidized in a blender. 1M sodium hydroxide (NaOH) is added to neutralize the mixture and then centrifuged to separate the supernatant (which contains the NE) from the solid precipitate (containing the GE). Before the GE is extracted, the non-gelling extract (NE) is removed. The GE is then extracted using an adaptation of a method developed by Turquois et al. (Turquois, et al. Extraction of highly gelling pectic substances from sugar beet pulp and potato pulp: influence of extrinsic parameters on their gelling properties. Food Hydrocolloids 1999, 13, (3), 255-262). The solids are mixed with 7.5 g/L sodium hexametaphosphate [(NaPO.sub.3).sub.6] in 50 mM NaOH, in a 1:1 mass-to-volume ratio of solids to solution. The mixture is stirred for 1 h, then vacuum filtered with knitted polyester cloth or Whatman 41 filter paper to obtain the filtrate. The filtrate pH is lowered to 2 using hydrochloric acid (HCl) and refrigerated overnight (? 5? C.) in order to precipitate the GE. The precipitate is separated by centrifugation, re-suspended in sufficient deionized (DI) water to cover the pellet, and the pH is adjusted to 8.0 with 1M NaOH to re-dissolve the precipitate. The resulting solution is purified by successive filtering through a 1.2 ?m and a 0.45 ?m membrane. The GE is re-precipitated with acetone or isopropanol in a 2:3 liquid-to-solvent volume-to-volume ratio, then is washed with alcohol and dried under ambient conditions.
(93) The non-gelling extract (NE) is collected as described above, and sodium chloride is added to the supernatant to form a final concentration of 1M NaCl. The supernatant is filtered with knitted polyester cloth or Whatman 41 filter paper, based on the viscosity of the liquid, to obtain the filtrate. Acetone or isopropanol is added in a 2:3 volume-to-volume ratio of supernatant to solvent to precipitate the NE. The precipitate is washed with ethanol-water mixtures in a graded series (70%, 80%, 90%, 95% ethanol, and absolute ethanol) to remove any remaining impurities. The precipitate is left to dry at room temperature overnight, followed by an overnight drying in an air oven.
(94) Extraction of Mucilage (Second Method)
(95) In another embodiment, mucilage is alternatively extracted from fresh cactus pads as NE in which the cactus pads are washed, dried, weighed, and subsequently cut longitudinally in halves. The parenchyma (white fleshy inside) of the pads is scooped out with a spoon and pressed through a potato press to crush the parenchyma and break the mucilaginous cells thereby releasing the mucilage. Alternatively, the crushing of mucilaginous cells may be achieved with other tools, such as crushing the material with a stone or mortar and pestle.
(96) The pressed liquid is collected and the solids are discarded. Isopropanol is added to the liquid in a volume-to-volume ratio of 3:2 alcohol to liquid to precipitate the mucilage. The precipitate is washed with three 5 mL to 10 mL aliquots of isopropanol. The precipitate is placed on a petri dish to dry overnight and subsequently is oven dried at 50? C. overnight. The dry precipitate is then pulverized with a mortar and pestle and stored in an airtight plastic vial.
(97) Extraction of Mucilage (Third Method)
(98) In a further embodiment, cactus pads are washed, dried, weighed and diced into approximately 1 cm cubes. The cactus cubes are then immersed in 1% sodium chloride solution in a 1:1 mass to volume ratio. Liquid is added to the material until the solution covered the diced cactus. The mixture is boiled for 15 minutes then cooled. The liquid and solids are squeezed through a potato press and the liquid is retained while the residual solids are discarded. Isopropanol is added to the liquid in a 3:2 alcohol to liquid volume-to-volume ratio to precipitate the mucilage. The precipitate is washed with three 5 to 10 mL aliquots of isopropanol. The precipitate is placed on a petri dish to dry overnight then it is oven dried at 50? C. overnight. The dry precipitate is then pulverized with a mortar and pestle and stored in an airtight plastic vial.
(99) Extraction of Mucilage (Fourth Method)
(100) In a further embodiment, for the extraction of nongelling extract (NE) and gelling extract (GE), cactus pads are cleaned and boiled in milli Q water until they become tender (approximately 20 minutes). The soft pads are then liquefied in a blender. The pH of the resulting suspension is then neutralized and the solids and liquid supernatant are separated in a centrifuge at 4000 rpm. The supernatant is collected, mixed with 1M-NaCl solution (10:1 ratio), filtered and precipitated with 1:2 ratio of pulp to acetone to produce the NE extract. The acetone is then decanted and the precipitate washed with a 1:1 volume ratio of precipitate to isopropanol. The resulting NE precipitate is air dried on a watch glass at room temperature.
(101) In order to separate the gelling portion, the centrifuged precipitates are mixed with 50 mL of 50 mM NaOH. The suspension is stirred for 10 min and the pH adjusted with HCl to 2. The suspension is centrifuged and the solids again resuspended in water while the pH is adjusted to 8 with NaOH. The suspension is then filtered and the solids are washed following the same procedure as for the NE extract.
(102) For the combined extract, the initial blend is centrifuged and the supernatant is separated and pH adjusted to 8 with NaOH, washed with acetone and isopropanol as described above and finally it is air-dried. On average, for each pad that weighs around 300 g wet weight, a 1.5-2 g dry powder is obtained.
(103) Use of Mucilage in Random Configuration
(104) The mucilage obtained by any of the described methods of extraction is added to the soil. For a random configuration, the mucilage may be added to the soil with no distinct pattern, for example by blending or mixing of the mucilage into the soil. This configuration is the easiest to achieve as the mucilage is mixed with the soil.
(105) The mucilage may be mixed with inorganic or organic compounds such as nutrients or ions/ionic compounds prior to being blended with the soil. Alternatively, inorganic or organic compounds can be added to the soil after incorporation of the mucilage. Alternatively, the nutrients or ion/ionic compounds can be present in the soil prior to mixing in the mucilage. In some embodiments, the nutrients are added to the water that is added to the system. The nutrients are transported along with the water molecules by the mucilage in all embodiments. Nonlimiting examples of inorganic and organic compounds include, but are not limited to, ions, macronutrients, micronutrients, fertilizers, pesticides and insecticides.
(106) The interactions of mucilage with soil compounds is optimized and finely-controlled depending on the carrier volume and cactus mucilage concentration.
Example 5-3D Mucilage Configuration in Bio-Enriched Soil (Prophetic)
(107) Cactus mucilage's natural ability to bind and release individual macronutrients, micronutrients and water can greatly contribute to a more sustainable agriculture by making fertilizer and water use more efficient and cost-effective.
(108) A composition of cactus mucilage may be used which includes both gelling extract (GE) and non-gelling extract (NE) or alternatively, either GE or NE may be used individually.
(109) Cactus mucilage can be extracted by various methods. The most common method uses water as a solvent for maceration, followed by a filtration process and precipitation. Other methods include use of a mechanical press with or without subsequent precipitation. Methods for extracting mucilage are known in the art as described in Gheribi et al., herein incorporated by reference into this disclosure. (Ghiribi, R. et al., 2019, Cactus mucilage for food packaging applications, Coatings, 9:655).
(110) Extraction of Mucilage (First Method)
(111) In an embodiment, mucilage is extracted from fresh cactus pads. The pads are washed, dried and weighed. The pads are diced or peeled and boiled for 20 min, then the mixture is liquidized in a blender. 1M sodium hydroxide (NaOH) is added to neutralize the mixture and then centrifuged to separate the supernatant (which contains the NE) from the solid precipitate (containing the GE). Before the GE is extracted, the non-gelling extract (NE) is removed. The GE is then extracted using an adaptation of a method developed by Turquois et al. (Turquois, et al. Extraction of highly gelling pectic substances from sugar beet pulp and potato pulp: influence of extrinsic parameters on their gelling properties. Food Hydrocolloids 1999, 13, (3), 255-262). The solids are mixed with 7.5 g/L sodium hexametaphosphate [(NaPO.sub.3).sub.6] in 50 mM NaOH, in a 1:1 mass-to-volume ratio of solids to solution. The mixture is stirred for 1 h, then vacuum filtered with knitted polyester cloth or Whatman 41 filter paper to obtain the filtrate. The filtrate pH is lowered to 2 using hydrochloric acid (HCl) and refrigerated overnight (? 5? C.) in order to precipitate the GE. The precipitate is separated by centrifugation, re-suspended in sufficient deionized (DI) water to cover the pellet, and the pH is adjusted to 8.0 with 1M NaOH to re-dissolve the precipitate. The resulting solution is purified by successive filtering through a 1.2 ?m and a 0.45 ?m membrane. The GE is re-precipitated with acetone or isopropanol in a 2:3 liquid-to-solvent volume-to-volume ratio, then is washed with alcohol and dried under ambient conditions.
(112) The non-gelling extract (NE) is collected as described above, and sodium chloride is added to the supernatant to form a final concentration of 1M NaCl. The supernatant is filtered with knitted polyester cloth or Whatman 41 filter paper, based on the viscosity of the liquid, to obtain the filtrate. Acetone or isopropanol is added in a 2:3 volume-to-volume ratio of supernatant to solvent to precipitate the NE. The precipitate is washed with ethanol-water mixtures in a graded series (70%, 80%, 90%, 95% ethanol, and absolute ethanol) to remove any remaining impurities. The precipitate is left to dry at room temperature overnight, followed by an overnight drying in an air oven.
(113) Extraction of Mucilage (Second Method)
(114) In another embodiment, mucilage is alternatively extracted from fresh cactus pads as NE in which the cactus pads are washed, dried, weighed, and subsequently cut longitudinally in halves. The parenchyma (white fleshy inside) of the pads is scooped out with a spoon and pressed through a potato press to crush the parenchyma and break the mucilaginous cells thereby releasing the mucilage. Alternatively, the crushing of mucilaginous cells may be achieved with other tools, such as crushing the material with a stone or mortar and pestle.
(115) The pressed liquid is collected and the solids are discarded. Isopropanol is added to the liquid in a volume-to-volume ratio of 3:2 alcohol to liquid to precipitate the mucilage. The precipitate is washed with three 5 mL to 10 mL aliquots of isopropanol. The precipitate is placed on a petri dish to dry overnight and subsequently is oven dried at 50? C. overnight. The dry precipitate is then pulverized with a mortar and pestle and stored in an airtight plastic vial.
(116) Extraction of Mucilage (Third Method)
(117) In a further embodiment, cactus pads are washed, dried, weighed and diced into approximately 1 cm cubes. The cactus cubes are then immersed in 1% sodium chloride solution in a 1:1 mass to volume ratio. Liquid is added to the material until the solution covered the diced cactus. The mixture is boiled for 15 minutes then cooled. The liquid and solids are squeezed through a potato press and the liquid is retained while the residual solids are discarded. Isopropanol is added to the liquid in a 3:2 alcohol to liquid volume-to-volume ratio to precipitate the mucilage. The precipitate is washed with three 5 to 10 mL aliquots of isopropanol. The precipitate is placed on a petri dish to dry overnight then it is oven dried at 50? C. overnight. The dry precipitate is then pulverized with a mortar and pestle and stored in an airtight plastic vial.
(118) Extraction of Mucilage (Fourth Method)
(119) In a further embodiment, for the extraction of nongelling extract (NE) and gelling extract (GE), cactus pads are cleaned and boiled in milli Q water until they become tender (approximately 20 minutes). The soft pads are then liquefied in a blender. The pH of the resulting suspension is then neutralized and the solids and liquid supernatant are separated in a centrifuge at 4000 rpm. The supernatant is collected, mixed with 1M-NaCl solution (10:1 ratio), filtered and precipitated with 1:2 ratio of pulp to acetone to produce the NE extract. The acetone is then decanted and the precipitate washed with a 1:1 volume ratio of precipitate to isopropanol. The resulting NE precipitate is air dried on a watch glass at room temperature.
(120) In order to separate the gelling portion, the centrifuged precipitates are mixed with 50 mL of 50 mM NaOH. The suspension is stirred for 10 min and the pH adjusted with HCl to 2. The suspension is centrifuged and the solids again resuspended in water while the pH is adjusted to 8 with NaOH. The suspension is then filtered and the solids are washed following the same procedure as for the NE extract.
(121) For the combined extract, the initial blend is centrifuged and the supernatant is separated and pH adjusted to 8 with NaOH, washed with acetone and isopropanol as described above and finally it is air-dried. On average, for each pad that weighs around 300 g wet weight, a 1.5-2 g dry powder is obtained.
(122) Use of Mucilage in 3D Configuration
(123) The mucilage obtained by any of the described methods of extraction is added to the soil. For a 3D configuration, the mucilage may be added to the soil in vertical and horizontal lines, for example by injection of the mucilage into the soil. This configuration has more access points of contact between mucilage and soil. It also has more control on the regions that may need more water to water.
(124) If used in a soil container, mucilage solutions are running vertically at first from top to bottom, and then the soil container is rotated to run mucilage from top to bottom on the horizontal side. It is necessary to have the soil containers at enough pressure that the mucilage gets injected within the soil on straight vertical or horizontal lines as a result of the rotation
(125) The mucilage may be mixed with inorganic or organic compounds such as nutrients or ions/ionic compounds prior to being blended with the soil. Alternatively, inorganic or organic compounds can be added to the soil after incorporation of the mucilage. Alternatively, the nutrients or ion/ionic compounds can be present in the soil prior to mixing in the mucilage. In some embodiments, the nutrients are added to the water that is added to the system. The nutrients are transported along with the water molecules by the mucilage in all embodiments. Nonlimiting examples of inorganic and organic compounds include, but are not limited to, ions, macronutrients, micronutrients, fertilizers, pesticides and insecticides.
(126) The interactions of mucilage with soil compounds is optimized and finely-controlled depending on the carrier volume and cactus mucilage concentration.
Conclusion
(127) The inclusion of cactus mucilage as well as inorganic and organic molecules in soil produces a superior soil that is capable of retaining and providing nutrients and water efficiently.
(128) The disclosures of all publications cited above are expressly incorporated herein by reference, each in its entirety, to the same extent as if each were incorporated by reference individually.
(129) It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between. Now that the invention has been described,