Chemical composition and profile characteristics of Osage orange Maclura pomifera (Rafin.) Schneider seed and seed oil

Studies were conducted on the properties of seeds and oil extracted from Maclura pomifera seeds. The following values (on a dry-weight basis) were obtained for M. pomifera seed, respectively: moisture 5.88%, ash 6.72%, oil 32.75% and the high protein content 33.89%. The carbohydrate content (20.76%) can be regarded as a source of energy for animals if included in their diets. The major nutrients (mg/100 g oil) were: potassium (421.65), calcium (218.56) and magnesium (185.00). The physicochemical properties of the oil include: the saponification number 174.57; the iodine value 141.43; the p-anisidine value 1.86; the peroxide value 2.33 meq O₂/kg; the acid value 0.66; the carotenoid content 0.59 mg/100 g oil; the chlorophyll content 0.02 (mg/100 g oil) and the refractive index 1.45. Polymorphic changes were observed in thermal properties of M. pomifera seed oil. This showed absorbency in the UV-B and UV-C ranges with a potential for use as a broad spectrum UV protectant. The main fatty acids of the crude oil were linoleic (76.19%), oleic (13.87%), stearic (6.76%) and palmitic acid (2.40%). The polyunsaturated triacylglycerols (TAGs) LLL, PLL, POL + SLL, OLL, OOL (L: linoleic acid, O: oleic, P: palmitic acid and S: stearic acid) acids were the major TAGs found in M. pomifera seed oil. A relatively high level of sterols making up 852.93 mg/100 g seed oil was present. The sterol marker, β-sitosterol, accounted for 81% of the total sterol content in the seed oil and is followed by campesterol (7.4%), stigmasterol (4.2%), lupeol (4.1%) and Δ⁵-avenesterol (3.2%). The seed oil was rich in tocopherols with the following composition (mg/100 g): α-tocopherol 18.92; γ-tocopherol 10.80; β-tocopherol 6.02 and δ-tocopherol 6.29. The results showed that M. pomifera seed oil could be used in cosmetic, pharmaceutical and food products.     

Evapotranspiration,yield, and water-use efficiency responses of Lesquerella fendleri at different growth stages

Lesquerella fendleri (Gray) Wats. is a potential new oilseed crop for the arid southwestern United States. Lesquerella seed oil with similar properties as castor oil is being considered as a domestic replacement for the imported castor oil. Development of new crops with low irrigation needs is of high priority. Because the most critical stage of sensitivity to moisture deficits has not been determined in Lesquerella species, the objectives of this study were: (i) to identify the most critical stage or stages for moisture deficit and, (ii) to determine the effect of moisture deficit on yield, yield components, oil and fatty acid composition. Two-year field studies were conducted at the New Mexico State University, Leyendecker Plant Science Research Center. The experimental design was a randomized complete block. The treatments consisted of (a) T1: Continuous favorable soil moisture [irrigated at 50% soil water depletion (SWD)]. (b) T2: Moisture stress (75% SWD) from establishment to initial flowering with no stress from flowering to final harvest (50% SWD). (c) T3: No stress imposed from establishment to initial flowering (50% SWD) followed by stress to final harvest (75% SWD). (d) T4: Moisture stress (75% SWD) from establishment to final harvest. The amount of water applied ranged from 810 to 729 mm for the first year, and 810 to 625 mm for the second year. Seed weight per plant and number of pods per plant were generally higher when water availability was maintained at or above 50% SWD throughout the growing season. Neither seed number per pod nor seed size was influenced by irrigation treatments. Lesquerella was more sensitive to water availability during flowering and seed development as a greater loss in seed yield occurred when irrigation was delayed to 75% SWD during that stage of development. Seed yield and dry matter production from the 2 year field studies were closely related to the seasonal cumulative evapotranspiration. For each millimeter of evapotranspiration, seed yield increased from 1.8 kg ha⁻¹ mm in 1994–1995 to 1.3 kg ha⁻¹ mm for 1995–1996. The dry matter production increased 13.4 kg ha⁻¹ for each mm increase in seasonal evapotranspiration during 1994–1995. This relationship was a second order polynomial with an R² of 0.86 during 1995–1996. The WUE_gr and WUE_dm were highest under the most favorable water availability conditions for growth and seed development. Delaying irrigation to 75% SWD throughout the crop growth period resulted in the lowest oil content. Lesquerolic acid content was not affected by irrigation during both the growing seasons.     

Large applications of fertilizer N at planting affects seed protein and oil concentration and yield in the Early Soybean Production System

An inverse relationship between soybean [Glycine max (L.) Merr.] seed protein and oil concentration is well documented in the literature. A negative correlation between protein and yield is also often reported. The objective of this study was to determine the effect of high rates of N applied at planting on seed protein and oil. Nitrogen was surface-applied at soybean emergence at rates of 290 kg ha⁻¹ in 2002, 310 kg ha⁻¹ in 2003, and 360 kg ha⁻¹ in 2004. Eight cultivars ranging from Maturity Group II–IV were evaluated under the Early Soybean Production System (ESPS). However, not all cultivars were evaluated in all 3 years. Glyphosate herbicide was used in all 3 years and a non-glyphosate herbicide treatment was applied in 2002. Cultivars grown in 2003 were also evaluated under an application of 21.3 kg ha⁻¹ of Mn. All cultivar, herbicide, and Mn treatments were evaluated in irrigated and non-irrigated environments with fertilizer N (PlusN treatment) or without fertilizer N (ZeroN treatment). When analyzed over all management practices (years, cultivars, herbicide, and Mn treatments), the PlusN treatment resulted in a significant decrease in protein concentration (2.7 and 1.9%), an increase in oil concentration (2.2 and 2.7%), and a decrease in the protein/oil ratio (4.7 and 4.6%) for the irrigated and non-irrigated environments, respectively. However, the overall protein and oil yield increased with the application of fertilizer N at planting (protein: 5.0% irrigated, 12.7% non-irrigated and oil: 9.9% irrigated and 18.9% non-irrigated). These increases were due to the increase in seed yield with the application of large amounts of fertilizer at planting. Additionally, a significant correlation (r = 0.45, P = 0.0001) was found between seed protein concentration and seed yield. No significant correlation was found between seed oil concentration and seed yield. The data demonstrate the inverse relationship between protein and oil and indicate that large amounts of N applied at planting do not change this relationship.     

Determination of selection criteria for seed yield and seed oil content in Vernonia (Vernonia galamensis variety ethiopica)

The magnitude of relationships among different traits is important in plant breeding programs to identify the best selection criteria and improve the efficiency of selection. This study was conducted to determine relationships between seed yield and seed oil content with other important agronomic traits among 36 diverse accessions of Vernonia (Vernonia galamensis variety ethiopica), a potentially novel industrial oilseed crop. Field evaluations were conducted during 2005, 2006 and 2007 at the Limpopo Province in South Africa using a partially balanced lattice design. Simple correlation and path analysis were performed to identify the best selection criteria for increased seed yield and seed oil content. Simple correlation and path analyses revealed that the formation of productive primary heads strongly associated with increased seed yield (r_g = 0.81, p < 0.001). Furthermore, path analysis indicated selection for increased number of primary heads would bring about simultaneous and favorable change towards reduced days to maturity and shorter plant height. Further associational study of traits with seed oil content showed a significant (p < 0.05) correlation between oil content with 1000 seed weight (r_g = 0.4). The path analysis, however, exposed seed yield followed by 1000 seed weight with significant direct effect on seed oil content. The study demonstrated that selection for increased number of productive primary heads is the principal selection criterion to improve seed yield. Whereas selection for 1000 seed weight and increased seed yield serve as major selection criteria to achieve increased oil content in V. galemanesis.     

Effects of cooking and screw-pressing on functional properties of protein in milkweed (Asclepias spp.) seed meals and press cakes

This study determined the effects of oil processing conditions on functional properties of milkweed seed proteins to evaluate their potential for value-added uses. Flaked milkweed seeds were cooked at 82 °C (180 °F) for 30, 60 or 90 min in the seed conditioner, and then screw-pressed to extract the oil. Proximate composition and protein functional properties of cooked flakes and press cakes were determined and compared with those of unprocessed ground, defatted milkweed seeds. Milkweed seed protein was most soluble at the pH range of 7–10, had excellent emulsifying properties, and produced substantial but highly unstable foams. Heat applied during seed cooking and screw-pressing did not reduce protein solubility and improved emulsifying, foaming, and water-holding capacities. Emulsifying capacity was much higher at pH 10 than at pH 7. These results showed that the protein in both the milkweed seed and its press cake from oil processing has useful functional properties that could be utilized in applications such as paint emulsifier and adhesive extender.     

Seed physiological maturity in Cuphea

Cuphea (Cuphea viscosissima Jacq. × C. lanceolata f. silenoides W.T. Aiton, line PSR23) is a new crop being developed in the North Central United States, as an industrial oilseed crop. Cuphea PSR23 seed oil is rich in medium-chain-length fatty acids such as capric acid used to manufacture soaps and detergents. The objective of this research was to determine the time when physiological maturity of cuphea seed is reached and how seed development affects seed moisture, weight, oil content, fatty acid content, germination, and seedling vigor. To evaluate seed development, 2000 cuphea flowers were tagged at anthesis in the field at Prosper, North Dakota in 2004 and 2005. Each flower was tagged when open and the position on the main stem or branch was recorded. Two hundred capsules from the tagged flowers were harvested at 3- to 4-d intervals from 5- to 48-d post anthesis (DPA). Seed weight increased as a function of growing degree days (GDD) and the days from anthesis. Physiological maturity occurred when maximum dry seed weight was attained. Seed weight increases followed the Gompertz function with a R² = 0.90 (2004) and R² = 0.95 (2005). All capsules, regardless of their position on the stem, followed the same growth function for seed weight. The maximum dry seed weight estimated by the Gompertz function was 3.61 for 2004 and 3.58 mg seed⁻¹ for 2005. Physiological maturity estimated with a quadratic function occurred at 38 DPA or 270 GDD in 2004. In 2005, physiological maturity occurred at 26 DPA or 265 GDD. As a visual indicator when the capsules split-open seeds inside that capsule are physiologically mature. Seed moisture decreased from 900 g kg⁻¹ at 37 GDD post anthesis to 450 g kg⁻¹ at 319 GDD post anthesis in 2004; however, in 2005 seed moisture decreased from 850 to 81 g kg⁻¹ at 293 GDD post anthesis. Seed germination increased as seed developed and it was 83% when harvested 234 GDD post anthesis. Oil content increased from 98 g kg⁻¹ at 37 GDD post anthesis to 279 g kg⁻¹ 319 GDD post anthesis. Fatty acid composition varied throughout seed development. Seed development for 111 GDD and greater had more than 66% of capric acid (10:0). Cuphea should be harvested after 265 GDD post anthesis when most capsules on the main stem are split-open, have attained maximum seed weight, germination, seedling vigor, and oil content.     

Preparation of biodiesel from Idesia polycarpa var. vestita fruit oil

The feasibility of producing biodiesel from Idesia polycarpa var. vestita fruit oil was studied. A methyl ester biodiesel was prepared from refined I. polycarpa fruit oil using methanol and potassium hydroxide (KOH) in an alkali-catalyzed transesterification process. The experimental variables investigated in this study were catalyst concentration (0.5–2.0 wt.% of oil), methanol/oil molar ratio (4.5:1 to 6.5:1), temperature (20–60 °C) and reaction time (20–60 min). A maximum yield of over 99% of methyl esters in I. polycarpa fruit oil biodiesel was achieved using a 6:1 molar ratio of methanol to oil, 1.0% KOH (% oil) and reaction time for 40 min at 30 °C. The properties of I. polycarpa fruit oil methyl esters produced under optimum conditions were also analyzed for specifications for biodiesel as fuel in diesel engines according to China Biofuel Systems Standards. The fuel properties of the I. polycarpa fruit oil biodiesel obtained are similar to the No. 0 light diesel fuel and most of the parameters comply with the limits established by specifications for biodiesel.     

Divergent selection at ultra-low plant density for seed protein and oil content within soybean cultivars

Soybean [Glycine max (L.) Merr.] seed is a major source of protein for animal feed and oil for human consumption. Selection within elite soybean cultivars for the improvement of agronomic and seed traits is assumed to be ineffective due to the belief that cultivars are highly homogeneous. Previously reported data suggest that latent variation among the single plant selections within a cultivar exists and that mechanisms that generate de novo variation may also be present. The main objective of this study was to perform divergent single-plant selection at ultra-low plant density and investigate the presence of genetic variation for seed protein and oil within three elite soybean cultivars. A secondary objective was to investigate the variation for fatty acid composition. In 1995, single plants from the three cultivars were grown in a honeycomb design using a plant-to-plant spacing of 0.9 m. A total of 333 plants from ‘Benning’, 392 plants from ‘Haskell’, and 371 plants from ‘Cook’ were evaluated. Divergent single-plant selection for protein and oil content was performed to select a total of 20 plants for high or low protein and 20 plants for high or low oil from each cultivar. The selected plants were further evaluated in replicated row-plot experiments for 3 years. Our results indicate that single-plant selection at low plant density was successful in discovering significant variation for seed protein and oil within each of the three soybean cultivars. For protein content, the magnitude of intra-cultivar variation between the highest- and lowest-protein lines averaged 19 g kg⁻¹ across the three cultivars and ranged from 13 to 24 g kg⁻¹. For oil composition, the magnitude of variation between the most divergent lines averaged 12 g kg⁻¹ across the three cultivars and ranged from 9 to 14 g kg⁻¹. Significant variation among the selected progeny lines was also discovered for specific fatty acid composition. The magnitude of intra-cultivar variation averaged from 6 to 29 g kg⁻¹ across the five fatty acids of soybean. The genetic variation discovered within the soybean cultivars is most likely due to latent variation and/or newly created variation. Our data provide evidence that single-plant selection at ultra-low plant density within elite cultivars can be effective in improving the seed composition of a soybean cultivar.     

Oil extraction from lesquerella seeds by dry extrusion and expelling

Whole lesquerella seeds with 6% (as is) and 12% moisture content (MC) were extruded at different residence times by varying screw speeds and feed rates. The temperature of the extrudate was recorded and its MC was determined. The extent of seed cooking was evaluated by measuring the protein solubility and thioglucosidase (TGSase) activity in the extrudate. Uncooked whole seeds (UWS), whole seeds cooked in seed cooker (CWS), and extrusion-cooked seeds (ECS) were screw pressed and the crude oils were analyzed for foots, free fatty acid (FFA), phosphorus, calcium, magnesium, and sulfur. The screw speed and feed rates employed resulted in residence times ranging from 22 to 110 s. The corresponding exit temperatures of the extrudates ranged from 88 to143 °C. Seeds with 6% initial MC dried to 4.3% at extrudate temperatures ≤125 °C regardless of residence time, while seeds with 12% initial MC came out at 7–9% MC, Extruding seeds with 6 and 12% starting MC for 34 and 41 s, respectively, provided the same degree of cooking as that of 12% MC CWS. All CWS and ECS tested negative for TGSase activity. ECS with 6% initial MC generated much higher foots (6.4–9.4%) in the oil compared with that of the 12% MC ECS (1–1.7%). The crude oils from CWS had the lowest FFA content at 1.25%. Crude oils from UWS and ECS had FFA ranging from 1.4–2.8%. The crude oil from 12% MC CWS had 374 ppm sulfur which was 3–8× higher than what were found in crude oils from 6% MC CWS and ECS. The highest P (23 ppm), Ca (14 ppm), and Mg (6 ppm) levels in the crude oil were from 12% MC CWS, which were comparable to total degummed oils. An 81% oil recovery from 6% MC ECS (22 s residence time) was obtained at 19 rpm expeller screw speed. Increasing the expeller's screw speed from 19 to 37 rpm decreased the oil recovery by 0.2%/rpm, increased the throughput by 3.3 kg/rpm from 70 to 130 kg/h, and reduced the press load from 91 to 67%.     

Milkweed seed wing removal to improve oil extraction

Milkweed is now being grown commercially mainly for the production of floss used as hypoallergenic fillers in pillows and comforters. More recently, the use of milkweed seed oil in soaps and personal care products is being explored. The oil used in this effort was obtained by screw pressing whole milkweed seeds. The milkweed seed has a considerable amount of paper-thin wing around the edge of the hull. The light wing contributes greatly to the low bulk density of the seeds and the efficiency of oil extraction. This study explored the feasibility of removing the wings from the seeds to reduce the amount of material going into oil extraction. Hand-fractionation of the seeds showed that the wings, hulls, and kernel accounted for 12.2%, 51.2%, and 36.5% of the seed weight, respectively. The wing contained 1% of the total oil. Most of the oil is in the kernel (73%), but a significant amount is also found in the hulls (22.4%). Mechanical removal of seed wing was evaluated using an impact huller. Seeds (1 kg) with 4%, 7.2%, and 10% moisture were passed through the huller running at 1250 and 1750 rpm impeller speeds. The seeds discharged from the huller were screened to separate the intact seeds and partially dewinged seeds, dewinged seeds, and fines. Seed wings were effectively removed at seed moisture contents and impeller speed combinations of 7% and 1250 rpm or 10% and 1700 rpm. This was verified using 100 kg seeds. Removing the wings reduced the weight of the seeds by 13%, reduced the volume by 46%, and increased the bulk density by 63% while losing less than 5% of the total oil. The oil content of the dewinged seeds was 16.6% higher than the whole seeds. These reductions in seed weight and volume can significantly increase the output of the oil extraction equipment.     

High antioxidant potential of pressing residues from evening primrose in comparison to other oilseed cakes and plant antioxidants

Evening primrose (Oenothera biennis) is increasingly cultivated for medicinal use of the γ-linolenic acid rich oil. The seed cake (EPSC) – the remaining industrial residue from cold pressing – was extracted with polar solvents in order to investigate a profitable polyphenolic recovery. The extractable matter and the total phenolic content (Folin-Ciocalteu) have been compared to a black currant residue from juice production (Ribes nigrum) and seed cakes from sesame, woad (Isatis tinctoria) and burdock (Arctium lappa). The EPSC crude extracts yielded the high total phenolic content (min 228.2 ± 11.6 to max 696.4 ± 29.0 mg GAE g⁻¹ dry extract) within the range of already commercialized antioxidant extracts from rosemary (RO, 142.1 ± 1.9 mg g⁻¹), green tea (GT, 446.8 ± 27.4 mg g⁻¹) and grape seed (GS 790.0 ± 53.1 mg g⁻¹). All extracts exhibited free radical scavenging activity (DPPH assay) with the order of potency: EPSC > GS > GT ≫ burdock = black currant > RO > butylated hydroxytoluene (BHT) ≫ woad > sesame. Accordingly EPSC extracts where very effective in scavenging superoxide anion radicals (neotetrazolium assay: GS > EPSC > GT ≫ BHT > burdock > woad > sesame) and inhibition of lipid oxidation (Rancimat assay: BHT ≫ GT > EPSC ≫ burdock > woad > RO > sesame > GS). Decreasing Rancimat activity from 80 °C upwards might indicate heat sensitiveness and limited usability. However, an efficient exploitation of polyphenols from evening primrose seed cakes in terms of an uncomplicated extraction procedure, the yield and the competitive profile as a strong radical scavenger can be concluded.     

Synthesis and physical properties of estolides from lesquerella and castor fatty acid esters

Biodegradable, vegetable oil-based lubricants must have better low temperature properties as well as comparable cost to petroleum oils before they can become widely acceptable in the marketplace. The low temperature property usually measured is the pour point (pp), the minimum temperature at which the material will still pour. Viscosity and viscosity index also provide information about a fluid's properties where a high viscosity index denotes that a fluid has little viscosity change over a wide temperature range. Lesquerella oil is a good candidate for its development into a biodegradable lubricant as it is being developed as an alternative crop for the southwestern U.S. The hydroxy site on the fatty acid (FA) makes it a suitable site for esterification to yield estolides. Castor and lesquerella FA esters were combined with different types of saturated, unsaturated, and branched FAs to produce estolides. Castor and lesquerella estolide esters had the best cold temperature properties when capped with oleic (pp = −54 °C for castor and pp = −48 °C for lesquerella) or capped with a branched material, 2-ethylhexanoic acid (pp = −51 °C for castor and pp = −54 °C for lesquerella). As the saturation was increased in the estolide, pour and cloud points also increased. The increased saturation such as in stearic capped estolides allowed for sufficient alkyl stacking of these long saturated chains producing higher pour points. Oxidative stability of the estolides was compared between the oleic-castor estolide 2-ethylhexyl ester and the coco-castor estolide 2-ethylhexyl ester by the rotating bomb oxidation test (RBOT). The RBOT times for both estolides were low with a similar time of about 15 min. However, when the antioxidant package (3.5 wt.%) was added, the RBOT times increased to 403 min for the coco-castor estolide 2-ethylhexyl ester while still retaining its outstanding cold temperature properties, (pp = −36 °C and cp = −30 °C). The viscosity index ranged from 164 to 200 for these new hydroxy FA derived estolide 2-ethylhexyl esters. These oleic-castor and lesquerella estolide esters have displayed far superior low temperature properties (pp = −54 °C) than any other estolides reported to date. Due to the lack of solvent and catalysts, the cost of these estolides should be reasonable and more suitable as a base stock for biodegradable lubricants and functional fluids than current commercial materials.     

Influence of sources and doses of N and K on herbage,oil yield and nutrient uptake of patchouli [Pogostemon cablin (Blanco) Benth.] in semi-arid tropics

Patchouli oil is one of the most important essential oils used in modern perfumery and cosmetic industries. There is hardly any preparation of oriental nature where patchouli oil is not used. It is used mainly because of fixative property as it gives tenacity to other perfumes. Field experiments were conducted at Bangalore, India, to study the influence of sources and doses of N and K on herbage, oil yield, nutrient uptake, nitrogen utilization efficiency and oil content of patchouli [Pogostemon cablin (Blanco) Benth.]. The results revealed that application of 200 kg N/ha and 41.5 kg K/ha produced significant higher patchouli herbage and oil yields compared with controls. Similarly, N and K uptake were also higher at 200 kg N and 41.5 kg K/(ha year) compared with controls. DCD-coated urea produced higher herbage, oil yield and N uptake and utilization efficiency compared with prilled urea. There was no effect of sources of K on the yield of patchouli. The oil content was not influenced by N, K doses or sources applied. N and K depletion were noticed in the soil.     

Microwave irradiation effects on the structure,viscosity, thermal properties and lubricity of soybean oil

Soybean oil is a highly valuable agricultural commodity for the United States. To further add value to soybean oil, chemical and physical modifications, as well as additives, have been extensively used to change the oil characteristics and properties, broadening the potential industrial applications. Heat treatments such as heat-bodying have been implemented to change soybean oil properties, but no research has studied the effects of microwave-irradiation on soybean oil structure and properties.Soybean oil (SBO) was heat-bodied (HB) or microwave-irradiated (MI). HB and MI (200–250 °C for 20–60 min) oil had similar Gardner bubble viscosity (B–C range). SBO that was HB or MI had increased viscosity compared with untreated SBO. ¹H NMR analysis showed no oxidation occurred for all treatments. However, HB and MI oil formed a cyclic ring structure with polymerization that most likely contributed to the increased viscosity. Pour point decreased from −9 °C for the untreated SBO, −15 °C for the HB, and −18 °C for the MI despite viscosity increases. Pour point anomaly is likely due to triacylglyceride cyclic ring formation. Pressurized DSC analysis showed higher oxidative stability for HB oil with even higher stability for MI oil. Compared with untreated SBO, HB and MI oil increased friction coefficient and decreased film percentage, whereas MI oil tended to leave larger wear scratches on the ball and disk during friction measurements. MI oil improved SBO cold-flow behavior, but reduced its potential as a lubricant.     

Synthesis and characterization of hazelnut oil-based biodiesel

The demand for diesel fuel far exceeds the current and future biodiesel production capabilities of the vegetable oil and animal fat industries. New oilseed crops that do not compete with traditional food crop are needed to meet existing energy demands. Hybrid hazelnut oil is just such an attractive raw material for production of biodiesel. Hazelnut oil was extracted from hybrid hazelnuts and the crude oil was refined. Hazelnut oil-based biodiesel was prepared via the transesterification of the refined hazelnut oil with excess methanol using an alkaline catalyst. The effects of reaction temperature, time and catalyst concentration on the yield of diesel were examined, and selected physical and chemical properties of the biodiesel were evaluated. The biodiesel yield increased with increasing temperature from 25 to 65 °C and with increasing catalyst concentration from 0.1 to 0.7 wt%. The increase in yield with reaction time was nonlinear and characterized by an initial faster rate, followed by a slow rate. Hazelnut oil-based biodiesel had an average viscosity of 8.82 cP at 25 °C, which was slightly higher than that of the commercial soy-based diesel (7.92 cP at 25 °C). An approximate 12 °C higher onset oxidative temperature and a 10 °C lower cloud point of hazelnut oil biodiesel than those of its commercial soy counterpart indicated a better oxidative stability and flowability at low temperature. The average heat of combustion of hazelnut oil biodiesel was 40.23 kJ/g, and accounted for approximately 88% of energy content of diesel fuel. The fatty acid composition of hazelnut oil-based biodiesel was the same as the nature oil.     

Castor yield in response to planting date at four locations in the south-central United States

Oilseed crops have potential use in the production of biodiesel. Currently, most oil going into the production of biodiesel is derived from soybean (Gylcine max L.) grown in the central U.S. Inability of the southeastern states to compete with central U.S. soybean production has lead to the search for alternative oilseeds. The high oil content and unique properties of castor (Ricinus communis L.) give it potential for use as biodiesel. However, there is limited information on potential yields, adaptation, and planting dates of adaptation of modern castor cultivars. This study was designed to determine potential yields and ideal planting dates of castor at various locations in Mississippi and Tennessee. A single castor cultivar was sequentially planted at 14 day intervals, at four locations, ranging from Memphis, TN south to Poplarville, MS. Annual planting occurred from 1 April to 1 July at all locations, except the 1 April planting date was excluded from the two northern locations. Mean yield ranged from 89 to 1954 kg ha^?1. Northern most locations and earliest plantings resulted in the greatest yields. Precocious flowering of castor immediately after 1 April planting at Shubuta, MS was associated with a lower yield. This flowering event was also observed at Poplarville, but did not significantly affect yield. The yield reductions due to southern planting coupled with precocious flowering at the southern locations seem to indicate a limited zone of adaptation for castor.     

Physical properties of triglyceride estolides from lesquerella and castor oils

Lesquerella is a developing hydroxy oilseed crop suitable for rotation in the arid Southwestern United States. The hydroxy oil of lesquerella makes it suitable for esterification into triglyceride estolides. The estolide functionality imparts unique physical properties that make this class of materials suitable for functional fluid applications. Lesquerella and castor hydroxy triglycerides were converted to their corresponding estolides by reacting the oils with saturated fatty acids (C2–C18) in the presence of a tin 2-ethylhexanoate catalyst (0.1 wt.%) and utilizing the condensation of hydroxy with corresponding anhydride or heating under vacuum at 200 °C. Two homologous series of estolides for each triglyceride were synthesized for comparison, mono-capped (one hydroxy functionality per triglyceride molecule) and full-capped (all hydroxy functionalities per triglyceride molecule). Physical properties (pour point, cloud point, viscosity, and oxidative stability) were compared for this estolide series. The longer chain saturate capped estolides (C14–C18) had the highest pour points for both mono-capped (9 °C, C18:0) and full-capped (24 °C, C18:0) lesquerella estolides. Castor mono-capped (9 °C) and full-capped (18 °C) triglyceride estolides gave similar properties. However, pour points improved linearly when the shorter saturated fatty acid capping chain lengths were esterified with the hydroxy triglycerides. Lesquerella capped with a C6:0 fatty acid had pour points of −33 °C for the mono-capped and −36 °C for the full-capped and castor had −36 and −45 °C, respectively. Oxidative stabilities of the estolides were compared for oleic, lauric and lauric-hydrogenated mono- and full-capped materials by rotating bomb oxygen test (RBOT). RBOT times for oleic and lauric capped estolides were low and similar with times centered around 15 min. However, when antioxidant (4 wt.%) was added the RBOT times increased to 688 min for the hydrogenated full-capped lesquerella lauric estolide. The antioxidant had little effect on RBOT times when 2 wt.% or less antioxidant was added for all the estolides except those that were hydrogenated. The hydrogenated estolides showed improvements in oxidative stability at all concentrations of antioxidant tested. Viscosity index ranged from 130 to 202 for all estolides with the shorter chain length capped estolides gave the lower viscosity index values. Viscosity at 100 °C ranged from 13.9 to 26.6 cSt and the 40 °C viscosity ranged from 74.7 to 260.4 cSt where the longer chain length capped estolides gave the highest viscosities.     

Extraction of pennycress (Thlaspi arvense L.) seed oil by full pressing

Pennycress is currently being developed as an oilseed crop for biofuel production. Pennycress seeds harvested from a field near Peoria, Illinois, provided our first opportunity to conduct an oil extraction study on a pilot scale. The goals of this study were to determine the effects of seed moisture and cooking on the pressing characteristics of pennycress seeds and to evaluate the quality of the oils extracted. Pennycress seeds (60 kg) with 9.5 and 16% moisture contents (MC) were cooked and dried (82–104 °C) using a steam-heated 3-deck laboratory seed cooker. The residence times were varied to produce cooked seeds with MCs ranging from 1.0 to 13.0%. The cooked seeds were pressed immediately using a heavy duty laboratory screw press. Pressing rate, press load, and residual oil in the press cakes were determined. The oils extracted were analyzed for solids content (foots), free fatty acid (FFA) content, color, and phosphorus (P), calcium (Ca), magnesium (Mg), and sulfur (S) contents. Pressing uncooked pennycress seeds with 9.5% MC produced press cake with 10.7% oil (db), extracting 75.1% of the oil in the seed. Cooking and drying the seeds between 3 and 4% MC provided the highest oil recovery at 86.3 and 88.0% for seeds with 9.5 and 16% starting seed MC, respectively. The pressing rates and press loads at these MCs were similar. Compared to the oil from uncooked seeds, the oils from cooked seeds had higher foots (1.55–1.73% vs. 0.52%), slightly higher FFA contents (0.40–0.46% vs. 0.30%), and slightly higher red values in AOCS RY color scale (4.1R–6.2R vs. 2.4R). Cooking increased the phosphatide content but the amount was still comparable to degummed oils. The sulfur levels in the expelled oil were higher than the amounts found in rapeseed oil and varied considerably depending on the seed moisture and the extent of cooking employed.     

Moisture-dependent physical properties of jatropha seed (Jatropha curcas L.)

The study was conducted to investigate some moisture-dependent physical properties of jatropha seed namely, seed dimension, 1000 seed mass, surface area, sphericity, bulk density, true density, angle of repose and static coefficient of friction against different materials. The physical properties of jatropha seed were evaluated as a function of moisture content in the range of 4.75–19.57% d.w. The average length, width, thickness and 1000 seed mass were 18.65 mm, 11.34 mm, 8.91 mm and 741.1 g, respectively at moisture content of 4.75% d.w. The geometric mean diameter and sphericity increased from 12.32 to 12.89 mm and 0.66 to 0.67 as moisture content increased from 4.75 to 19.57% d.w., respectively. In the same moisture range, densities of the rewetted jatropha seed decreased from 492 to 419 kg m⁻³, true density increased from 679 to 767 kg m⁻³, and the corresponding porosity increased from 27.54 to 45.37%. As the moisture content increased from 4.75 to 19.57% d.w., the angle of repose and surface area were found to increase from 28.15° to 39.95° and 476.78 to 521.99 mm², respectively. The static coefficient of friction of jatropha seed increased linearly against the surfaces of three structural materials, namely plywood (44.12%), mild steel sheet (64.15%) and aluminum (68.63%) as the moisture content increased from 4.75 to 19.57% d.w.     

Submergence tolerance and yield performance of lowland rice as affected by agronomic management practices in eastern India

Rice is subjected to excessive waterlogging and flash-flooding on large areas in south and south-east Asia. Besides cultivars, submergence tolerance of plants is influenced by various agronomic practices. A field experiment was conducted at Cuttack, India during 1994–1995 to study the effect of method of stand establishment (direct seeding and transplanting), vigour of seed (low and high-density) or seedlings (N-fertilized and unfertilized), plant population (normal and 50% more) and N fertilizer (single basal and split application) on yield performance of lowland rice under conditions of natural submergence and simulated flash-flooding (impounding up to 90 ± 3 cm depth for 10 days at vegetative stage). Flooding reached a maximum depth of 80 cm in 1994 and 52 cm in 1995 under natural submergence. The crop performance was better in 1994 due to timely sowing in dry soil and delayed accumulation of water (43 days after sowing) than in 1995 when sowing was done late in saturated soil followed by early water accumulation (28 days after sowing). Grain yield of rice decreased by 30.0–33.6% due to simulated flash-flooding compared with natural submergence, and by 21.4–33.1% due to transplanting in July compared with direct seeding in May-end/early June. The yield of direct-sown crop increased by using high-density seed of 22.9–23.0 mg weight (5.2–9.0%), higher seed rate of 600 m⁻² (2.2–2.3%) and basal fertilization at 40 kg N ha⁻¹ (19.4–25.7%) compared with low-density seed (19.4–20.1 mg), 400 seed m⁻² and no N, respectively. The yield of transplanted crop increased by using N-fertilized seedlings of 0.49–1.65 g weight (29.5–38.5%), higher number of seedlings at 155 m⁻² (3.5–16.7%) and basal fertilization at 40 kg N ha⁻¹ (31.9–32.5%) compared with unfertilized seedlings (0.19–0.79 g), 115 seedlings m⁻² and no N. Split application of 40 kg N ha⁻¹ — 50% each at basal and top dressing (105–115 days of growth after flash-flooding) — improved yield significantly (10.1–13.1%) over single basal application under simulated flash-flooding, but not under natural submergence conditions. Regression analysis indicated that relative contribution of various factors in increasing grain yield was in order: N fertilizer > seed density > seed m⁻² in direct-sown rice, and N fertilizer > seedlings m⁻² > seedling dry weight in transplanted rice. It was concluded that grain yield of flood-prone lowland rice can be increased by establishing the crop early through direct seeding using high-density seed and basal N fertilization.