METHOD FOR LESS DENSELY POPULATED CULTIVATION OF MONARDA FISTULOSA FOR PRODUCTION OF THYMOQUINONE

Abstract

A method for cultivating Monarda for production of thymoquinone includes plug planting Monarda fistulosa and/or Monarda didyma plants between about 24,000 and about 44,000 plants per acre. The cultivation method produces plants bearing oil without weed contamination and reduces herbicide use due to production of natural herbicides by the monarda plants. The method results in increased production of essential oils including thymoquinone and thymohydroquinone and may include propogating plants from clones to obtain thymohydroquinone at levels up to about 40% or more of the recovered oils.

Claims

1. A method for cultivating plants of at least one species of Monarda selected from a group consisting of the species fistulosa and dydima, to increase yield of at least one constituent of an oil of said plants, said at least one constituent selected from the group consisting of thymoquinone and thymohydroquinone, said method comprising preparing a field for planting at least one of Monarda fistulosa and Monarda dydima, growing at least about 24,000 Monarda plants per acre, and harvesting plants grown in said field.

2. The method of claim 1 further comprising planting seed of Monarda fistulosa with a broadcast seeding device at a rate of between about 2.5 pounds and about 5 pounds per acre.

3. The method of claim 2 further comprising using a soil compression device after seeding for at least partially sealing in moisture.

4. The method of claim 1 further comprising planting plug plants of Mondarda fistulosa at a rate between about 24,000 and about 44,000 plugs per acre.

5. The method of claim 1 further comprising a plurality of growing seasons wherein said plants are mowed at least once after a first growing season, and harvested after each of the remaining plurality of growing seasons.

6. The method of claim 4 further comprising separating at least a portion of the oil from a plurality of said plants wherein more than half of the plants in said field are clones of a single source and the yield of thymoquinone and thymohydroquinone together comprise at least about 30% of the separated oil.

7. The method of claim 6 wherein the separated oil further comprises less than about 5% thymol.

8. The method of claim 4 wherein a portion of the plants are propagated from a single clone and the oil yielded comprises at least about 30% thymoquinone and thymohydroquinone combined and at least about 20% carvacrol.

9. The method of claim 1 wherein the oil yielded comprises about 5% to about 42% thymoquinone and about 5% thymohydroquinone and less than about 10% of one of carvacrol or thymol.

10. The method of claim 1 wherein harvesting plants comprises cutting the plants, gathering the plants, and separating said oil from the cut and gathered plants by steam distillation.

11. The method of claim 1 wherein at least one quality of said at least one essential oil is improved over methods where plants per acre are less, and said at least one quality comprises reduction of levels of contamination of the oil caused by the presence of other plants.

12. The method of claim 10 wherein harvesting said plant comprises a delay between cutting the plants and collecting said oil.

13. The method of claim 10 wherein said oil is steam distilled between about 2 hours and about 6 hours after cutting the plants.

14. The method of claim 1 wherein said at least about 24,000 Monarda plants per acre comprise almost all Monarda fistulosa plants, said plants comprising a plurality of leaves and at least one seed head, and further comprising separating said at least one constituent from the oil using a process comprising distillation of at least a portion of said leaves and said seed heads.

15. The method of claim 14 wherein separating said at least one constituent yields an amount of thymoquinone of at least about 5% of the oil.

16. The method of claim 15 said at least one constituent further comprising carvacrol wherein separating said at least one constituent further yields an amount of carvacrol of at least about 20% of the oil.

17. The field of the method of claim 1 wherein Monarda fistulosa the oil separated from a plurality of the plants harvested comprises thymoquinone, carvacrol, and thymol wherein said thymoquinone comprises at least about 30% of said oil and said carvacrol comprises at least about 20% of said oil.

18. The field of the method of claim 1 wherein a plurality of the plants yield oil comprising between about 34% and about 37% thymoquinone and between about 20% and about 27% carvacrol.

19. The method for cultivating of claim 1 wherein harvesting the plants grown in the field comprises cutting the plants, gathering the cut plants, and distilling oil from the cut and gathered plants.

20. The method of claim 19 wherein at least some of the plants each comprise at least one seed head, said method comprising separating a plurality of seed heads from said at least some of the plants, gathering the plurality of seed heads, and distilling oil from said seed heads.

21. The method of claim 19 further comprising delaying distillation between about 2 to about 24 hours after harvest.

22. The method of claim 20 wherein at least some of said plants further comprise leaves, said method further comprising separating said leaves from the plants and distilling oil from said leaves.

23. The method of claim 22 said method further comprising distilling oil from the leaves and seed heads together.

24. A method for cultivating a field of plants of Monarda fistulosa to increase yield of thymoquinone, said method comprising plug planting Monarda fistulosa in rows between about 12 inches and about 24 inches apart at a rate between about 24,000 and about 44,000 plants per acre, allowing said plants to mature until a plurality of said plants including at least one seed head, separating at least the seed heads from said plants after flowering and separating oil from the seed heads wherein the oil yielded comprises more thymoquinone than thymohydroquinone.

25. The method of claim 24 further comprising an increase in a yield of thymohydroquinone.

26. The method of claim 24 wherein 5% of the oil comprises thymoquinone.

27. The method of claim 24 wherein between about 5% and about 30% of the oil comprises thymoquinone.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIG. 1 flow chart describing the cultivation process;

[0038] FIG. 2 perspective view of means for transporting;

[0039] FIG. 3 end view of means for transporting; and

[0040] FIG. 4 schematic illustrating steam distillation components.

[0041] FIG. 5 chart showing levels of constituents in the oil harvested from plants grown according to the described cultivation process.

DETAILED DESCRIPTION

[0042] The present invention comprises planting seed of Monarda fistulosa or any of the species listed in Table 1 in a field at a rate between about 2.5 lbs per acre and about 5 lbs per acre and more preferably between about 3.5 and 4.5 lbs per acre. Alternatively, plants 14 may be plug planted at a rate between about 24,000 and about 44,000 per acre in either 24 inch or 12 inch rows. The field 12 which is plug planted may be mowed regularly the first year without harvesting the plant or its seed heads/blooms or, preferably, planted in the fall and harvested the first summer without the need for mowing. In either case, the Monarda plants may provide good oil yields for several consecutive years, Harvest may include stems (generally the section above the ground level), along with leaves and seed heads, or may be more limited to harvesting just heads without stems and leaves, or seed heads with leaves. The lifetime of plants 14 for a single planting is typically 5-7 harvests, but may be longer or shorter depending on soil conditions, climate and husbandry practices.

[0043] The equipment used to condition the field, plant the seed (where seeding is employed rather than plug planting), or, alternatively, plant the plugs, mow the plants, cut the plants, and gather the heads and leaves or whole plants may each be of any type readily known and understood by one of skill in the art. Examples of each of these types of equipment are provided herein by machine producer's brand name but they are provided strictly for purposes of example, and not for limitation. Specifically, a Draper head on a forage chopper can be used followed by blowing the foliage into a wagon or other container for moving to the distillery. Seed drills, if used, may be, for example, a Great Plains drill with small seed attachment and 8 inch rows. If broadcasting seed, a Terrogator may be employed.

[0044] Referring now to FIG. 1 the field 12 is prepared 2 by routine tilling, field cultivating, discing or other means for turning or loosening the upper layer of soil. For example and not for limitation, a disc 16 by CaseIH, Krause, or other implement dealer may be used. Depending on soil type, fertilizer may or may not be applied. Next, the field is seeded 4 or plug planted. Seed 10 may be drilled or broadcast. When drilled, spacing of about 8 inches to about 10 inches is desired. Although many permissible drills exist, two examples are produced by Brillion or Taka. Alternatively, the seed 10 may be broadcast. Again, a variety of acceptable broadcasting devices are available such as a TerraGator. In either case, broadcasting or drilling, seed 10 should be planted at the rates mentioned above. When plug planting, rates suggested are from about 24,000 to about 44,000 in rows spaces between about 12 inches and about 24 inches. Some weeding may be required in the first year. Thereafter, very little weeding is expected to be required as the plants include their own alleopathy as well as shade other smaller plants and aggressively use the nutrients in nearby soil.

[0045] Alternatively, and in a preferred method plants may be plug planted at generally even spacing for about 24,000 to about 44,000 plugs per acre. The plugs may be planted in rows or groups or generally equidistant.

[0046] In another method, planting (via drill or broadcast or other means) is preferably followed by rolling or other soil compression activities 6. An example of an acceptable roller device is a Riteway model 4300 which weighs between 15,800 lbs and 23,500 pounds. Rolling or other compression actions are preferably completed the same day as the field is cultivated and also, and more critically, within 2 to 48 hours after drilling or broadcasting seed. The timing is recommended in order to avoid over drying the soil, protect the seeds from birds, and to compress the soil enough to create a seal to assist in retaining the remaining moisture to improve germination percentages for the seeds.

[0047] In another method, the soil may be prepared to minimize clods and provide soil texture amenable to plug planting. Thereafter, plugs may be planted. However, a sealing process is not critical for the transplanted plants.

[0048] During the first season (whether seeded or plug planted), the field 12 may be mowed 8 on a regular basis or, especially where the field is plug planted, will not be mowed the first year. Depending on rainfall, soil and climate conditions, mowing may be done as often as 4-6 times in a first season for seeded fields or as infrequently as 2-4 times. Mowing frequency is dictated by the height of the plants. Weeds grow much faster in the first season than does the Monarda when seeded, so mowing is aimed to keep the weed height reduced to allow the Monarda to become established. Mowing should be done to maintain the field between about 8 and 10 inches and, more preferably when they are about 8 inches tall, as many times in the first season as needed to keep the plants less than about 8 to 10 inches high. At the end of the first growing season, the plants are preferably left around 8 inches tall to catch snowfall. Any suitable mowing machine 24 may be employed. For example, several models of the Woods bat-wing mower work well.

[0049] It is foreseeable that seeds 10 planted in a bare field 12 the first season where ground cover or crop previously existed may be subjected to some weed pressure early in the growing season of that first year. When this occurs, application of Assure II or Select Max work well. Other herbicides applications 10 are also likely to be effective, however, broadleaf herbicides should not be used because they damage Monarda.

[0050] The second growing season is unlikely to require any herbicides, however, Assure II, Basagran and SelectMax are but a few examples of herbicides that may be employed if needed. Due to the planting rate, the compression of the soil, and multiple mowings in the first season in seeded fields, plants will emerge early and tend to grow quickly. Monarda fistulosa plants 14 produce their own herbicidal chemicals one of which is carvacrol. These chemicals act to control any weeds that are not simply physically crowded out by the Monarda. The action of the carvacrol effects germination of the weed seeds. The planting rate, the growth rate, the size of the plants, and the Monarda's own chemical defenses result in a crop that typically requires no further herbicide treatments but for, perhaps, an occasional weed patch which may be controlled via hand sprayer or physical removal.

[0051] In midsummer, whether seeded fields or plug planted, Monarda fistulosa plants produce a lavender colored fragrant flower. The plants may be harvested at flower peak which, in the Midwest United States, is generally early to mid July. The flowers and seed heads contain the essential oil as do the stems and the leaves.

[0052] Harvest of Monarda fistulosa fields cultivated in the manner of the present invention may be accomplished in several ways using various equipment. A preferred method is to employ is a MacDon draper or any other cutting machine to cut 12 the plants 14 with flowers attached, transferring the plants, then distilling the oil from the plant parts either within a few hours of harvest or at a later time. Alternatively, the plants and flowers may be left to lay in the field or in a transport container for 2 to up to about 6 or 12 hoursor about 24 hours but doing so may not provide the highest oil yields and may result in contamination of the plant material. Alternatively, the plants (alternatively, the flower heads only, or the flowers and leaves only) may be harvested freshcut and transported directly to the still. In short, the plants do not need to be distilled immediately after harvest which allows for efficient harvest operations when acreage levels and still volumes are not perfectly matched.

[0053] In one embodiment, means to transport 30 the cut plants 14 comprises a generally watertight wagon having a floor 32, two sides 34, 36, and two ends 38 and 40 with multiple ports 41-45 near the floor 32 in one of the ends 38 or 40. The wagon 30 just described is used in one of several methods for removing oil from Monarda fistulosa, specifically steam distillation.

[0054] Steam distillation of oil from plants is old in the art and works on the principle that steaming the cut plants (or portions of the cut plants) encourages release of the plants' essential oils via rupture of the plant's oil sacs which are taken up with the steam. During steam distillation 20 a boiler 48 creates steam 50. The steam 50 travels through a conduit 51 to said means to transport 30 (or some other container wherein said plant parts are present) and enters through ports 41-45 near the floor 32. The steam travels upward moving oil 52 that has been released upward with the steam 50. The steam 30, with oil 52, is removed through the port 56 into a second conduit 58. The steam 50 and oil 52 is run through a condenser 54 which causes the oil 52 and water in the steam 50 to condense and allows the oil 52 to be separated and recovered 22. When using the wagon 30, a steam input 61 is connected to each port 41-45. Steam is injected into the wagon and, as it travels upwards, oil 52 from the plants 14 is removed with the steam. The steam and oil then exit the top of the wagon through the port 56 and flow into or through one of many different kinds of condensers 60 where the oil 52 is recovered and the condensed steam (water) may or may not be reheated and reused in the process.

[0055] During distillation the essential oils are separated from the distillate in an order characteristic of the oil and related to the boiling point of that oil. (See Table 2 below) Thymoquinone separates just before thymol and carvacrol and thymohydroquinone separates just after carvacrol.

TABLE-US-00002 TABLE 2 compounds molecular weight boiling points alpha pinene 136.24 155 alpha thujene 136 155 alpha terpinene 136.237 164 beta myrcene 136.23404 167 para cymene 134.22158 179 gamma terpinene 136.23404 182 linalool 154.252 198 terpinene-4-ol 154.249 212 thymoquinone 164.204 231 thymol 149.66 232 carvacrol 150.221 238 caryophyllene 204.356 256 thymohydroquinone 166.217 306

[0056] The method of cultivation just described increases germination, decreases herbicide use and fuel use, and increases the yield of Monarda fistulosa oil generally, and specifically, effects relative amounts of carvacrol, thymol,and thymoquinone (TQ) and thymohydroquinone (THQ). At least after the first year's growth, and more commonly also after the first year including harvest, the TQ and THQ levels, together, may constitute about 5% to about 35%, of the oil distilled and either carvacrol or thymol constitute over 20% of the oil distilled, or together constitute over 20% of the oil distilled. The oil content may be more closely predicted by selecting and cloning plants that produce particularly desirable oil profiles and propagating those clones. Some of these clones have been collected and tested to yield 35% to even more than 40% thymoquinone. (see table below):

[0057] See Table below:

TABLE-US-00003 YIELD Plant TQ % THY % CARV % 1 27.82 7.17 0.17 2 26.89 0.43 19.00 3 26.24 3.09 1.25 4 36.58 2.01 1.35 5 28.28 1.47 2.96 6 47.45 1.22 2.31 7 28.60 0.52 4.27 8 23.34 0.87 1.99 9 28.03 1.41 1.33 10 38.51 1.42 .61 11 27.41 6.19 1.62 12 39.68 4.27 1.19 13 31.56 4.92 0.89 14 24.37 29.67 0.83 15 20.5 29.32 1.80 16 29.73 12.28 1.37 17 26.00 1.31 7.18 18 22.58 10.51 5.91 19 24.14 0.77 1.39 20 37.82 2.27 6.26 21 22.57 1.38 0.61 22 29.53 0.76 1.5 23 23.9 0.65 0.9 24 23.86 8.54 2.66 25 28.60 0.97 1.6 26 29.91 2.87 3.81 27 29.98 9.75 1.05 28 15.58 0.34 0.39 29 32.64 6.18 0.62 30 32.78 5.36 0.65 31 31.52 0.22 1.51 32 24.76 10.13 2.07 33 34.01 0.61 3.71 34 30.91 8.94 2.77 35 24.35 18.08 1 36 34.12 3.5 0.87 37 25.83 1.57 1 38 33.36 8.17 1.34

[0058] Certain aspects of the oil profile can be manipulated by the way the Monarda is planted and cultivated as described herein. Combining cloning with the cultivation methods provided herein is well within the scope of the present invention.

[0059] The above-mentioned cultivation method results in oil content that is commercially desirable, namely, containing increased amounts of carvacrol, thymol, thymoquinone, and thymohydroquinone as compared to naturally occurring stands of Monarda fistulosa.

[0060] Although known recommended planting rates for Monarda fistulosa ranged from about 0.25 to up to 2 lbs per acre (Monarda fistulosa contains 1,120,000 seeds/lb), it was surprisingly found that these rates did not provide the better means for cultivating and harvesting the plants and obtaining the desired essential oils they contained at the level of oil quality and profile desired. Oil quality of the present invention is high at least partially due to the reduction and near elimination of weed pressure and its resulting contamination. The quality may also be partially attributed to low uses of herbicides or pesticides. The oil constituent profile is also beneficially affected by control of weed pressure under less chemical pressure and the cultivation practices described herein which affects the placement of the flowers on the plant. It is believed also that harvesting methodology at least relative to time between harvest and distillation, and perhaps also relative to plant parts, also attributes to oil profile.

[0061] Thus, the present invention has been described in an illustrative manner. It is to be understood that the terminology that has been used is intended to be in the nature of words of description rather than of limitation.

[0062] Many modifications and variations of the present invention are possible in light of the above teachings. For example, distillation may be accomplished in other ways; seeds may be planted via hand, or via traditional planters, or other seed planting devices not yet known. New effective herbicides may become known. New Monarda hybrids may be developed or clones may be made and it may be determined that other means may be employed to increase oil production even more, specifically the level of carvacrol or of thymoquinone or thymohydroquinone in the Monarda. Therefore, within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described.