Cuphea Seeds Research Articles

Cuphea Seed Oil as a Potential Alternative Natural Source of Medium-chain Triglycerides used for Healthier Cooking Applications

Cuphea is a potential new oilseed crop for temperate regions of the USA. 
 It produces and stores in its seeds medium chain length fatty acids, which currently are derived commercially from seeds of tropical palms.
 Cuphea seeds contain more than 30% of oil rich in medium-chain fatty acids, caprylic, capric, lauric, and myristic fatty acids (C8:0-C14:0). . 
 In this paper, we through the light on Cuphea seed oils as the only naturally cultivated seed oils that contain the most prominent Medium-chain triglycerides (MCT). 
 MCTs oils are trended in the last 20 years as the healthier dietary oil which is essentially nontoxic, noncarcinogenic, and nonmutagenic for human consumption. MCTs are readily hydrolyzed by digestive enzymes, and the fatty acid end products are rapidly absorbed into the bloodstream [1]. The gross energy content of MCTs is 8.3 kcal/g vs 9 kcal/g for fat or Long-chain triglycerides oils (LCTs oils). 
 The objective of this study was to introduce to the global edible oils industries an innovative potential natural healthier edible oil which contains that majority of its triglyceride compositions is based on medium-chain glycerides (MCT) with avoiding any chemical conversion process to get the MCT rich oils from tropical oils. It will be a basis for a lot of further researches to make its characteristics fulfilling all other nutritional and application needs of healthy cooking applications better than conventional seed or tropical oils.

Macro and Microminerals of four Cuphea genotypes grown across the upper Midwest USA

cuphea seed oil can be used for many purposes from motor oil and cosmetic components to jet fuel, because its seeds are a rich source of medium-chain fatty acids (C8:0 to C14:0). Processing cuphea oil to biofuel and other bioproducts of high quality can depend on the heavy metal content of its seed. However, little is known about the macro and micromineral content of its seed. The objective of this study was to evaluate mineral content of cuphea, especially heavy metal content for processing the oil into biofuels/bioproducts and to determine how this may differ across environments. Four cuphea genotypes were evaluated; two of which were semi-domesticated genotypes [PSR23 and HC-10 (Cuphea viscosissima Jacq. × C. lanceolata W.T. Aiton)] and two were wild species (Cuphea wrightii and C. viscosisima (VS-6-CPR-1). The study was conducted at four locations in North Dakota (ND), Minnesota (MN), Iowa (IA), and Illinois (IL). The soil was a Perella silty clay loam at Prosper, ND, a Barnes loam at Morris, MN, a Clarion loam at Ames, IA, and an Osco silt loam at Macomb, IL. PSR23 and HC-10 were directly-seeded in the field and the two wild species were transplanted. All cuphea seeds contained some heavy metals. Although phosphorus (P) and potassium (K) were equally fertilized at all sites, the concentrations of P and K in seeds of PSR23 and HC-10 tended to be lower at the MN site than IA and IL sites, while the lowest P concentration was observed at the MN site for VS-6 and C. wrightii. Among calcium (Ca), magnesium (Mg), and sodium (Na) in cuphea seeds, sodium had the lowest concentration. The average concentrations for microminerals ranged from 40 to 53mgkg−1 for zinc (Zn), from 11.9 to 14.1mgkg−1 for copper (Cu). These concentrations are low compared to those found in many livestock feeds. Lead (Pb) and vanadium (V) were sporadically observed at a few locations. Cobalt (Co) was only detected for VS-6 at IA and C. wrightii at IA and MN, while cadmium (Cd) was only found for HC-10 at ND, PSR23 at IA, and C. wrightii at ND. These results suggest that the concentrations of macro cuphea seeds varied by genotype and environment. This information will be useful for those industries interested in processing cuphea seed oil for manufacturing biofuels, cosmetics, and other specialty chemicals.

Dehulling of Cuphea PSR23 seeds to reduce color of the extracted oil

Abstract Oil extracted by screw pressing seeds of Cuphea PSR23 contained 200–360 ppm of chlorophyll. A high amount of bleaching clay was needed during refining to remove the chlorophyll in the oil. In this paper, we investigated the dehulling of the seed as a method of reducing the chlorophyll content in oil extracted from cuphea seeds. The effects of seed moisture content, huller's impeller speed, and feed rate to the huller on dehulling of the seeds were determined. The hulls were separated from the cotyledons by screening and using a vacuum gravity separator. The oils extracted from the cotyledon-rich fraction were analyzed for chlorophyll content and color. The hulls accounted for 44.6% (w/w) of the whole cuphea seed. When seeds were dried to 3.5% moisture content (MC) before dehulling, 37% of the dehulled seed (containing 8.8% oil) can be removed by screening. This discard fraction has similar oil content to those of press cakes. The remaining cotyledon-rich fraction contained 39.2% oil, which is 38% greater than that of whole cuphea seeds. Hexane-extracted oil from the cotyledon-rich fraction contained 70% less chlorophyll content compared with similarly extracted whole seed oil. The minimum chlorophyll content achievable was 15 ppm from almost pure cotyledons and extracted by hydraulic pressing. Dehulling cuphea seed before oil extraction effectively reduced chlorophyll content in the oil, which can greatly decrease the amount of bleaching clay in oil refining and the cost associated with its handling and disposal.

Cuphea Seed Yield Response to Harvest Methods Applied on Different Dates

Cuphea, Cuphea viscosissima Jacq. × C. lanceolata W.T. Aiton, is a new crop that produces seed containing oil rich in medium‐chain fatty acids. Because cuphea has an indeterminate growth habit, timing of harvest is difficult to determine. The objective of this study was to determine the optimum harvest time and technique for maximizing seed yield. This research was conducted at Prosper, ND, in 2005 and 2006; Carrington, ND, in 2005; and Morris, MN, in 2005 and 2006. The experimental factors were four harvest treatments, direct‐nondesiccated (DND), direct‐desiccated (DD), swathed (SW), and desiccated‐swathed (DSW) applied on three different dates (D1, D2, and D3). Maximum seed moisture was 544 g kg−1, but seed moisture decreased 181 g kg−1 as the harvest date was delayed for the DND‐harvest treatment. Seed moisture reduction for the SW‐harvest treatment compared with the DND‐harvest treatment was 216 g kg−1 for D1. Swathing would be a better method than direct harvest or desiccation to reduce seed moisture at harvest. The harvested seed yields were not significantly different (P ≤ 0.05) among the DND‐, DD‐, and SW‐harvest treatments. Harvested seed yield reduction was observed only for the DSW‐harvest treatment. Swathing is also acceptable since no significant seed yield reduction was observed. Based on the returns after harvest treatments, the DND‐harvest treatment may be the most cost effective method to harvest cuphea seeds; however, it is not the most practical due to clogging of harvesting equipment, which slows down harvest.

Emergence of cuphea seeds treated with different fungicides

Cuphea ( Cuphea viscosissima Jacq. × C. lanceolata f. silenoides W.T. Aiton, Lythraceae) is an oilseed crop, with medium-chain fatty acids, being developed for the North Central United States for industrial applications in the manufacture of soaps and detergents. Seed germination and seedling emergence of cuphea is often low when compared to the commercial crops. Identification of seed treatments to optimize seedling emergence and stand establishment for cuphea are important for commercial production. The objective of this study was to determine the effect of several fungicide treatments on pure live seed emergence (PLSE) of cuphea. Pure live seed emergence is defined as total seedling emergence adjusted by the germination of the seed planted. Field experiments were conducted at Prosper, ND and Glyndon, MN, in 2005 and 2006. Previous crop rotations were soybean [ Glycine max (L.) Merr.]/hard red spring wheat ( Triticum aestivum L.), and soybean/hard red spring wheat/sugarbeet ( Beta vulgaris var. saccharifera L.) at Prosper and Glyndon, respectively, for both years. The experimental design was a randomized complete block with six treatments and four replicates. Treatments were: no fungicide applied (check treatment), captan, mefenoxam, fludioxonil + mefenoxam, azoxystrobin, and azoxystrobin + mefenoxam. Plant stand was counted and PLSE was calculated 10 to 15 d after seeding at all locations by counting emerged seedlings in the center two-plot-rows and adjusting PLSE for germination. Greenhouse experiments were conducted with soil treatments (pasteurized and non-pasteurized) and the same fungicide seed treatments as the field experiment. Pure live seed emergence, vigor index, and percent of diseased seedlings were recorded. Plant stand and PLSE were significantly greater for the seed treatments that had mefenoxam at the Glyndon, MN, environments, in which the previous crop was sugarbeet. Soil treatment (pasteurization) increased PLSE and vigor index. All fungicide seed treatments improved PLSE and vigor index and reduced damping-off compared to the untreated check. Results suggest that seed treatments including mefenoxam would be beneficial for commercial cuphea production.

Seed germination response of cuphea to temperature

Cuphea ( Cuphea viscosissima Jacq. × C. lanceolata W.T. Aiton; PSR23) is a potential new oilseed crop. Its oil is high in medium-chain fatty acids that are suitable for detergent/cleaner applications and also for cosmetics. The objective of this study was to determine the critical temperatures for cuphea seed germination. To determine the base, maximum, and optimum temperatures for seed germination, mature cuphea seeds were harvested from plants grown at Prosper, ND, in 2004, 2005, and 2006. Seeds were germinated on a temperature-gradient bar varying between 5 and 35 °C. Cumulative germination was calculated for each temperature treatment. Base temperature ( T b) and optimum temperature ( T o) were estimated from the third-order polynomial temperature-response functions for each year. In addition, germination rate per day was used in a linear model to estimate the base temperature below which germination rate was equal to zero ( T b), and the maximum temperature above which germination was equal to zero ( T m). The optimum temperature ( T o) was calculated as the intercept of sub-optimal and supra-optimal temperature-response functions. Through the third-order polynomial temperature-response functions and the sub-optimal/super-optimal intercept approaches, we were able to generate six estimates for each critical value. Estimates of the base temperature for cuphea seed germination ranged between 3.3 and 11 °C, with the most reliable estimates between 6 and 10 °C, similar to many warm-season crops such as corn ( Zea mays L.) and sorghum ( Sorghum bicolor L.). The optimum temperature for cuphea seed germination ranged between 18.5 and 24 °C with a mean value of 21 °C. The maximum temperature for seed germination ranged 33–38 °C. On this basis, a cuphea planting date after 20 May is recommended for east-central North Dakota.

Hydration of Cuphea seeds containing crystallised triacylglycerols.

Seeds that exhibit intermediate storage behaviour seem to die under conventional -18°C storage conditions. Cuphea wrightii A. Gray, C. laminuligera Koehne, C. carthagenensis (Jacq.) J.F. Macbr. and C. aequipetala Cav are considered sensitive to low temperature storage. The seeds of these species have triacylglycerols (TAG) that are crystalline at -18°C and melt when the seeds are warmed to >35°C. In contrast, seeds of tolerant species, C. lanceolata W.T. Aiton and C. hookeriana Walp., have TAG that crystallise at temperatures below -18°C and are fluid at 22°C. Cuphea seeds imbided while TAG are crystalline fail to germinate and exhibit visual damage. However, germination proceeded normally when dry seeds were warmed adequately to melt any crystalline TAG before imbibition. Reduced germination and cellular disruption including loss of lipid body compartmentation and fragmented protein bodies develop in seeds with crystalline TAG equilibrated to >0.1 g H2O g-1 DW. This damage cannot be reversed, even when seeds are dried before the damage can be visually detected. Results from this work reveal that the seeds of some species with intermediate type physiologies can be successfully placed into conventional -18 and -80°C storage facilities.

Effects of cooking and screw‐pressing on functional properties of Cuphea PSR23 seed proteins

AbstractThis investigation determined the effects of oil processing conditions on some functional properties of Cuphea PSR23 seed proteins to evaluate their potential for value‐added uses. Flaked Cuphea seeds were cooked at 82°C (180°F) for 30, 75, or 120 min in the seed conditioner and then screw‐pressed to extract the oil. Cooked flakes and press cakes were analyzed for proximate composition and protein functional properties. Results were compared with those of unprocessed ground, defatted Cuphea seeds. Protein from unprocessed Cuphea seeds had excellent emulsifying properties, poor foaming properties, poor solubility (10%) at pH 4–7, and much greater solubility at pH 2 and 10 (57 and 88%, respectively). Solubility profiles showed that cooking the flaked seeds to 82°C for 30 min resulted in a 50–60% reduction in soluble proteins. Cooking for 120 min gave <6% soluble proteins at all pH levels. Cooking for 75 min gave good oil yields but also resulted in <10% soluble proteins at pH 2–7 and 25% soluble proteins at pH 10. Seed cooking and screw pressing during oil extraction had significant detrimental effects on the solubility of Cuphea seed protein but generally improved its foaming capacity and emulsifying activity.

Massive cellular disruption occurs during early imbibition of Cuphea seeds containing crystallized triacylglycerols

The transition from anhydrobiotic to hydrated state occurs during early imbibition of seeds and is lethal if lipid reserves in seeds are crystalline. Low temperatures crystallize lipids during seed storage. We examine the nature of cellular damage observed in seeds of Cuphea wrightii and C. lanceolata that differ in triacylglycerol composition and phase behavior. Intracellular structure, observed using transmission electron microscopy, is profoundly and irreversibly perturbed if seeds with crystalline triacylglycerols are imbibed briefly. A brief heat treatment that melts triacylglycerols before imbibition prevents the loss of cell integrity; however, residual effects of cold treatments in C. wrightii cells are reflected by the apparent coalescence of protein and oil bodies. The timing and temperature dependence of cellular changes suggest that damage arises via a physical mechanism, perhaps as a result of shifts in hydrophobic and hydrophilic interactions when triacylglycerols undergo phase changes. Stabilizers of oil body structure such as oleosins that rely on a balance of physical forces may become ineffective when triacylglycerols crystallize. Recent observations linking poor oil body stability and poor seed storage behavior are potentially explained by the phase behavior of the storage lipids. These findings directly impact the feasibility of preserving genetic resources from some tropical and subtropical species.

Batch drying of cuphea seeds

Fresh mechanically harvested cuphea seed from the Midwest contains more than 50% moisture. Such high moisture leads to challenging drying problems. Cuphea seeds must be dried immediately to reduce moisture before destructive seed mold and material-clumping develop. A method had to be developed to batch dry large quantities of cuphea seeds. The freshly harvested, wet, uncleaned seeds were dried using a Grain Technology 245XL Dryer. Drier conditions were optimized over a 2 year period to yield a procedure for a batch drying process. In this process, the grain dryer was modified to help meet the demands of a small seed that has greater than 50% moisture at harvest. The seed moisture data was collected on a low-cost, commercially available G-7 Grain Moisture Meter, which can be used for different crops. The meter showed a strong correlation between the soybean setting and actual cuphea moisture content (%) measured in the lab when seed moisture was less than 20%. The cuphea seeds were dried to about 12% for storage.

THE COMBINED USE OF WHOLE CUPHEA SEEDS CONTAINING MEDIUM CHAIN FATTY ACIDS AND AN EXOGENOUS LIPASE IN PIGLET NUTRITION

In search for an alternative for nutritional antimicrobials in piglet feeding, the effects of adding whole Cuphea seeds, as a natural source of medium chain fatty acids (MCFA), with known antimicrobial effects, and an exogenous lipase to a weaner diet were studied. The foregut flora, the gut morphology, some digestive parameters and the zootechnical performance of weaned piglets were investigated. Thirty newly weaned piglets, initial weight 7.0 ± 0.4 kg, were divided according to litter, sex and weight in two groups (control diet; Cuphea+lipase diet). The Cuphea seeds (lanceolata and ignea) (50 g kg−1) were substituted for soybean oil (15 g kg−1), Alphacell (25 g kg−1) and soy protein isolate (10 g kg−1) in the control diet. Also 500 mg kg−1 microbial lipase was added to the Cuphea diet. The piglets were weighted individually on days 0, 3, 7, 14 and 16. Feed intake was recorded per pen during days 0 to 3, 3 to 7, 7 to 14 and 14 to 16. On day 7 five piglets of each experimental group were euthanized for counting the gastric and small intestinal gut flora and for gut morphology at two sites of the small intestine (proximal, distal). The results indicate a trend towards improved performances parameters by feeding Cuphea + lipase. The enzymic released MCFA (1.7 g kg−1 fresh gastric contents) tended to decrease the number of Coliforms in the proximal small intestine, but increased the number in the stomach and distal small intestine. With Cuphea, the number of Streptococci was significantly lower in small intestine, but not in the stomach, while the number of Lactobacilli was significantly lower in the distal small intestine and tended to be lower in the stomach and proximal small intestine. No differences between the diets were noted for the total anaerobic microbial load in the stomach or in the gut. Feeding Cuphea+lipase resulted in a significantly greater villus height (distal small intestine) and a lesser crypt depth (proximal and distal small intestine) and greater villus/crypt ratio depth (proximal and distal small intestine). The intra-epithelial lymphocyte (IEL) counts per 100 enterocytes were significantly decreased in the proximal small intestine and tended to decrease in the distal small intestine by feeding the Cuphea+lipase diet. Both phenomena are indicative for a more healthy and better functional state of the mucosa. Present results are in line with foregoing research, showing that manipulation of the gut ecosystem by the enzymic in situ released MCFA in the stomach and foregut can result in improved performances of the piglets, which makes the concept a potential alternative for in-feed nutritional antibiotics.

Reaction mechanism of recombinant 3-oxoacyl-(acyl-carrier-protein) synthase III from Cuphea wrightii embryo, a fatty acid synthase type II condensing enzyme

A unique feature of fatty acid synthase (FAS) type II of higher plants and bacteria is 3-oxoacyl-[acyl-carrier-protein (ACP)] synthase III (KAS III), which catalyses the committing condensing reaction. Working with KAS IIIs from Cuphea seeds we obtained kinetic evidence that KAS III catalysis follows a Ping-Pong mechanism and that these enzymes have substrate-binding sites for acetyl-CoA and malonyl-ACP. It was the aim of the present study to identify these binding sites and to elucidate the catalytic mechanism of recombinant Cuphea wrightii KAS III, which we expressed in Escherichia coli. We engineered mutants, which allowed us to dissect the condensing reaction into three stages, i.e. formation of acyl-enzyme, decarboxylation of malonyl-ACP, and final Claisen condensation. Incubation of recombinant enzyme with [1-(14)C]acetyl-CoA-labelled Cys(111), and the replacement of this residue by Ala and Ser resulted in loss of overall condensing activity. The Cys(111)Ser mutant, however, still was able to bind acetyl-CoA and to catalyse subsequent binding and decarboxylation of malonyl-ACP to acetyl-ACP. We replaced His(261) with Ala and Arg and found that the former lost activity, whereas the latter retained overall condensing activity, which indicated a general-base action of His(261). Double mutants Cys(111)Ser/His(261)Ala and Cys(111)Ser/His(261)Arg were not able to catalyse overall condensation, but the double mutant containing Arg induced decarboxylation of [2-(14)C]malonyl-ACP, a reaction indicating the role of His(261) in general-acid catalysis. Finally, alanine scanning revealed the involvement of Arg(150) and Arg(306) in KAS III catalysis. The results offer for the first time a detailed mechanism for a condensing reaction catalysed by a FAS type II condensing enzyme.

Characterization of two acyl-acyl carrier protein thioesterases from developing Cuphea seeds specific for medium-chain- and oleoyl-acyl carrier protein

Two acyl-acyl carrier protein (ACP) thioesterases were partially purified from developing seeds of Cuphea lanceolata Ait., a plant with decanoic acid-rich triacylglycerols. The two enzymes differ markedly in their substrate specificity. One is specific for medium-chain acyl-ACPs, the other one for oleoyl-ACP. In addition, these enzymes are distinct with regard to molecular weight, pH optimum and sensitivity to salt. The thioesterases could be separated by Mono Q chromatography or gel filtration. The medium-chain acyl-ACP thioesterase and oleoyl-ACP thioesterase were purified from a crude extract 29- and 180-fold, respectively. In Cuphea wrightii A. Gray, which predominantly contains decanoic a nd lauric acid in the seeds, two different thioesterases were also found with a similar substrate specificity as in Cuphea lanceolata.

Ultrastructural and biochemical characterization of the epidermal hairs of the seeds of Cuphea procumbens

Rehydration of desiccated Cuphea seeds results in a rapid morphological change in the seed. Within 20 min thread like epidermal hairs are present on the seed surface. The hairs, which are highly ordered helical structures, are present in the epidermal cells of the desiccated seed. Following emergence the hairs increase in length by means of an eversion process, the mechanism for which is proposed in the text. The hairs were purified to homogeneity and found to be composed of 55% carbohydrate and 45% protein. Following β-elimination of the carbohydrate using NaOH/NaBH4 one major protein of MW 31,000 was seen upon polacrylamide gel electrophoresis in the presence of sodium dodecylsulphate. The protein, here termed helexin, probably plays a major structural role in determining the helical shape of the hairs.

Cuphea procumbens: A model system for studying the mechanism of medium-chain fatty acid biosynthesis in plants

Seeds of Cuphea procumbens are rich in medium-chain fatty acids. In mature seeds, C10:0 constitutes over 80% of the fatty acid of the triacylglycerol fraction but is only a very minor constituent of the polar lipid fraction. C10:0 was found to a small extent in the neutral lipid fraction of other parts of the Cuphea plant but was absent from the polar lipid fraction — C10:0 thus acts as a marker for seed lipid biosynthesis. The fatty acid composition of maturing Cuphea seeds was analysed. Between 11–14 days after flowering C10:0 biosynthesis increases dramatically. Radioactive incorporation experiments using mature desiccated seeds demonstrate that they still have the capacity to synthesize C10:0. In vitro incorporation experiments demonstrate that 13–16-day-old seeds synthesize almost exclusively C10:0. These observations indicate that C. Procumbens is a good experimental system for studying the mechanism of medium-chain fatty acid biosynthesis in plants.