Major Resin Acids Research Articles

Tracing colophonium in consumer products.

Colophonium (rosin) can cause allergic contact dermatitis, mainly due to autoxidation of abietic acid (AbA). Products containing ≥0.1% colophonium should be labeled with EUH208 - "Contains rosin; colophony. May produce an allergic reaction." How should this be measured? To compare the results from different strategies for estimating colophonium levels in consumer products: (a) from AbA, and (b) the sum of all major resin acids. To investigate the ratio of 7-oxodehydroabietic acid (7-O-DeA)/AbA as indication of autoxidation. Resin acids were extracted from consumer products, derivatized, and then separated by gas chromatography/mass spectrometry (GC/MS). Resin acids were detected in 9 of 15 products. No product contained colophonium ≥0.1%. Estimation based on AbA resulted in underestimation of the colophonium levels in four of nine products. For three products, the obtained levels from this strategy were only one of two compared to when estimating from the sum of all resin acids. The ratio 7-O-DeA/AbA varied from 74% to 1.4%. We propose to measure colophonium based on the sum of all detectable major resin acids, including 7-O-DeA. The ratio of 7-O-DeA/AbA should be used as a marker of autoxidation, indicating an increased risk of sensitization. The presented analytical method is simple to use and suitable for further screening studies.

Integration of renewable cellulose and rosin towards sustainable copolymers by “grafting from” ATRP

A class of sustainable and renewable cellulose–rosin copolymers were prepared by immobilizing rosin-derived polymer chains on the backbone of ethyl cellulose (EC) by “grafting from” atom transfer radical polymerization (ATRP). Four different rosin based polymers derived from dehydroabietic acid (DA), one of the major resin acids in natural rosin, were attached to 2-bromoisobutyryl-functionalized EC. Meanwhile, DA-grafted EC was prepared by the simple esterification reaction between DA and EC. Kinetic studies showed that the polymerization of all monomers was controlled. These grafted copolymers adopt a worm-like or rod-like structure in tetrahydrofuran, verified by light scattering experiments. These copolymers have a tunable glass transition temperature and higher thermal stability in contrast to EC. Surface morphology by AFM analysis indicated good film-forming property when rosin polymers were grafted from EC. Additionally, the introduction of DA and rosin polymers remarkably enhanced the hydrophobicity of EC. The static contact angles of all these modified copolymers are above 90°. XPS analysis revealed that the surface of these rosin-modified EC copolymers was dominated by a hydrocarbon-rich rosin moiety. The UV absorption of modified EC composites is indicative of their potential application in UV-absorbent coating materials.

Terpenoids in the wood of Scots pine and Norway spruce seedlings exposed to ozone at different nitrogen availability

Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings were exposed to low-level ozone (O3) in an open-air exposure system for three or two growing seasons, respectively. Simultaneously, seedlings were supplied with nutrient solution containing either optimum (control) nitrogen (N), 70% of optimum N (low N availability), or 150% of optimum N (high N availability). Carbon-based secondary compounds, e.g., terpenes and resin acids, were analysed from the stemwood. α-Pinene, 3-carene, and limonene + β-phellandrene were the major terpenes in pine wood, whereas α-pinene, β-pinene, and limonene + β-phellandrene dominated in the spruce wood. Palustric + levopimaric and abietic acids were the major resin acids in the wood of both species. Ozone exposure did not cause any remarkable changes in the concentrations and proportional quantities of terpenes and resin acids in the wood of either tree species. Nitrogen availability did not affect the concentrations of carbon-based secondary compounds either, and the effects on proportional quantities were slight and ambiguous with respect to N supply. We conclude that realistically elevated levels of O3 do not have effects on concentrations of carbon-based secondary compounds of conifer wood and N availability might cause only slight changes in them. Therefore, our results do not directly support the carbon–nutrient balance hypothesis.

Resin bleed after painting from radiata pine boards treated with tributyltin naphthenate (light organic solvent preservative) or copper, chromium and arsenic compounds (water-borne preservative)

The degree of resin bleed from radiata pine boards was examined following preservation treatment, painting, and heating in an oven at 55°C for eight hours to simulate the effect of solar radiation. Two preservative types were compared: (a) tributyltin naphthenate solution (light organic solvent preservative or LOSP); and (b) copper chromium arsenic oxide solution (water-borne preservative or CCA). The CCA treatment, which involved a subsequent (90°C/60°C) kiln drying cycle, reduced resin bleed while LOSP treatment, after which kiln-drying is not appropriate, increased resin bleed. Spectroscopic analysis showed no evidence of reaction between resin components and CCA or LOSP treatment solutions. An acrylic paint coating system was more effective than an alkyd system in reducing resin bleed on LOSP-treated wood surfaces. Variability of resin bleed was associated with timber source and board sawing history. Both of these factors influenced LOSP uptake levels and undoubtedly contribute to the erratic occurrence of resin bleed in LOSP-treated boards. Control of the residual solvent level prior to exposure to solar radiation or heat may limit the potential for resin bleed after LOSP treatment. Wood of living trees contains the major resin acids (levopimaric, palustric and neoabietic) in approximately equal amounts but only traces of dehydroabietic acid (DHA). Heating of boards to 55°C followed by storage with air access for twelve months increased the proportion of DHA and its oxidation products and decreased the proportions of levopimaric, palustric and neoabietic acids.

Identification and Quantification of Nonvolatile Lipophilic Substances in Fresh Sapwood and Heartwood of Lodgepole Pine (Pinus contorta Dougl.)

Content and composition of lipophilic extractives from fresh sapwood and heartwood of lodgepole pine (Pinus contorta Dougl.) were investigated by solid-phase extraction, GC and GC-MS techniques. The acetone extractive content in sapwood was 1.9-2.2% of oven dry wood, among which were included 1.1-1.3% triglycerides, 0.02-0.03% free fatty acids, 0.3-0.4% free resin acids, 0.15-0.21% steryl esters and waxes, 0.02% monoglycerides, and 0.02-0.03% sterols, fatty alcohols and diglycerides. A considerably higher amount of extractives was present in heartwood, i.e., 10-12%, including 0.6-0.7% triglycerides, 0.8-1.1% free fatty acids, 4.0-5.6% free resin acids, 0.25-0.33% steryl esters and waxes, 0.4-0.5% monoglycerides, and 0.08-0.1% sterols, fatty alcohols and diglycerides. The most abundant fatty acid residues in the wood triglycerides were oleic (18:1), linoleic (18:2), linolenic (18:3) and palmitic (16:0) acids. Together they formed about 85% and 65% of the total fatty acid composition in the sapwood and heartwood triglycerides, respectively. Of the steryl esters and waxes, 18:2 was the most dominant residue, followed by 18:3 and 18:1. Twelve major free fatty acids and seven free resin acids were identified and quantified. The abundant free fatty acids in both sapwood and heartwood were 18:2 and 18:1, making up 32-41% and 24-28% of the total fatty acid amount, respectively. Palustric acid was the dominant free resin acid, its relative proportion to the total resin acids was 52% in the outer sapwood and 29% in the inner heartwood. Other major resin acids detected included abietic, isoabietic, dehydroabietic, neoabietic acids

Survival of pine sawflies in cocoon stage in relation to resin acid content of larval food

Several experiments were conducted to determine whether the ingestion of diterpenoids (resin acids) by pine sawfly larvae influences the survival of postlarval stages. Larvae of two diprionid sawfly species were reared on shoots of two Scots pine clones, one with a low (1.5% dry wt) concentration of resin acids and the other with a high (5.2% dry wt) concentration. No significant treatment-related differences were found in any of the experiments with respect to (1) resistance against parasitoids, (2) preference of predatory shrews and carabids, and (3) apparency of cocoons in the field to predators. A preference of sawfly prepupae to spin cocoon in feces from larvae reared on high resin acid needles was found. Possible explanations for these results are discussed. Detection of an unknown compound, possibly a breakdown product of the major resin acid in pine needles (pinifolic acid), in prepupae indicate that resin acids may be metabolized by the sawflies.

Determination of resin acids by gas chromatography and high-performance liquid chromatography in paper mill effluent, river waters and sediments from the upper Derwent Estuary, Tasmania

Resin acids in effluent from a paper mill situated on the upper Derwent Estuary near Hobart, Tasmania (Australia) were determined by HPLC analysis of their 7-methoxycoumarin-4-yl and 7-acetoxycoumarin-4-yl methyl esters. Total concentrations ranged from 1.0 to 4.8 mg 1 −1 with a mean of 2.7 mg 1 −1 during 1991–1992. Capillary GC-flame ionization detection and GC-MS analyses of organic constituents in river waters collected in April 1992 confirmed the presence of resin acids derived from the paper mill effluent, but the concentrations were highly variable and strongly influenced by freshwater flow and tidal movements. At a site just 500 m downstream of the effluent discharge, concentrations ranged from <0.01 to 0.78 mg 1 −1 over a 6-h period. Resin acids were also found in sediments close to the discharge (up to 87 mg kg −1 dry mass), but amounts in sediments downriver were generally considerably less (most samples <7 mg kg −1). The major resin acids in the effluent were dehydroabietic, palustric, abietic and pimaric acids. Smaller amounts of isopimaric, neoabietic, levopimaric and sandaracopimaric acids were also found. The proportions of individual resin acids in some of the water and sediment samples showed considerable differences from those in the effluent. The abundance of resin acids with conjugated double bonds such as palustric, levopimaric and neoabietic acids were particularly variable suggesting that they are more easily degraded. Resin acids of the pimarane type, such as pimaric acid, were considerably more stable. Variations in the water column distributions reflect both degradation of the more labile resin acids and redistribution of the resin acids between aqueous, colloid and sediment phases. Dehydroabietic acid was the most resistant to degradation and in some water samples it represented up to 66% of the resin acids compared with only 34% in the effluent. This result confirms earlier observations, and suggests that dehydroabietic acid could be used as a tracer for organic matter derived from the paper mill.

Diterpene resin acids: Major active principles in tall oil against Variegated cutworm,Peridroma saucia (Lepidoptera: Noctuidae)

Tall oil, a by-product of the kraft process for pulping softwood, has been shown to have insecticidal properties. In the present study, the active principles in tall oil against the variegated cutworm,Peridroma saucia Hübner, were investigated. GC-MS analysis showed that abietic, dehydroabietic, and isopimaric acids were major resin acid components of crude tall oil and depitched tall oil. When crude tall oil samples of differing resin acid composition were incorporated into artificial diet at a concentration of 2.0% fresh weight, they suppressed larval growth by 45-60% compared to controls. This suppression was significantly (P≤0.05) correlated with the equivalent contents of abietic, dehydroabietic, isopimaric, and total resin acids. These results were also evident from a diet choice test, showing that the second-instar larvae obviously selected diets with low levels of resin acids when different diets were randomly arranged in a Petri dish. Bioassays with pure resin acids (abietic, dehydroabietic, and isopimaric acids) demonstrated that all individual chemicals have similar bioactivity against this insect. Comparison of the bioactivities of depitched tall oil and an equivalent mixture of pure resin acids in thePeridroma chronic growth bioassay indicated that pure resin acids and depitched tall oil share a common mode of action to this insect. This study confirms that resin acids are major active principles in tall oil against the variegated cutworm, but other chemicals likely also contribute to the bioactivity of tall oil.

Composition of xylem resin from Pinus wallichiana and P. roxburghii

Turpentine from Pinus wallichiana xylem resin contained around 90% α-pinene. In addition to small amounts of other terpenes, isomers of undecane, dodecane and tridecane were detected as minor constituents. In contrast, P. roxburghii turpentine contained significant amounts of α-pinene, β-pinene and Δ-3-carene, the latter ( ca 50%) predominating. Several sesquiterpenes were identified for the first time in these Pinus species. Abietic and isopimaric acid were the major resin acids of both species but P. wallichiana alone contained lambertianic acid.

Subacute physiological effects of bleached kraft mill effluent (BKME) on the liver of trout, Salmo gairdneri

Rainbow trout ( Salmo gairdneri) were exposed for 10 and 30 days to microbiologically treated effluent of a bleached kraft pulp and paper mill (BKME). Throughout the experiments, the quality of dilution water, taken from an upstream location close to the mill, was allowed to vary both diurnally and seasonally (September–October) in a natural manner. The test concentrations averaged 0 (control), 0.6, 1.2, 2.0, and 5.1% (v/v) of BKME. Conjugates of all major resin acids and chlorinated phenolics of BKME, except chlorocatechols, were detected in trout bile. They comprised 93.1–99.9% of the total amounts in the bile. The level of conjugated resin acids increased linearly with the content of BKME in test water. On the other hand, no increase in concentration of conjugated phenolics was seen above 2.0% BKME. In the blood plasma no conjugates were analyzable. Concentrations of free resin acids in the blood plasma, but not in the bile, significantly increased at high test concentrations of BKME. No active excretion of free resin acids from plasma to bile can be inferred, but some of the phenolics—particularly 3,4,5,6-tetrachloroguaiacol—seem to be concentrated in the bile as a free compound. Changes in several biochemical parameters did not display any simple relationship with the external concentrations of BKME. In intermediate exposure concentrations, however, liver RNA and protein concentrations were decreased after 10 days but increased after 30 days. Condition of fish, relative size of the liver, and concentrations of liver glycogen and water were unresponsive to BKME at the dilutions investigated.

Major resin acids of Pinus nigra needles

Labdane diterpene acids were found to be the major resin acid components in Pinus nigra needles of various seed sources. The major constituents have been identified as 4-epiimbricataloic acid, manoyl oxide 19-oic acid, 4-epicommunic acid, and 15-monomethyl pinifolate. A GC method was developed to analytically differentiate pinifolic acid from its monomethyl ester in an admixture of both compounds. A minor resin acid was identified as 18-acetoxy-8(17)-labden-15-oic acid. 10-Nonacosanol and isoabienol were identified as major constituents of the needle and cortex extractives, respectively.

The behavior of resin acids during tall oil distillation

AbstractThe behavior of resin acids during tall oil distillation was studied by analyzing samples from six industrial‐scale processes. The same artifact resin acids were formed in all processes. However, the proportion of artifact resin acids in tall oil rosins varied from 8.3 to 18.3% of the resin acids. The lowest values were found for two processes utilizing thin‐film evaporators. The yield of resin acids in the tall oil rosin fraction varied from 62 to 80% of the resin acids in the crude tall oil feeds. Dehydroabietic acid was formed in all processes, the amount in rosin being 14‐44% more than in the crude tall oil feed. Of the abietic acid, only 45‐82% was recovered in the tall oil rosin fraction. The distribution of various resin acids and their reaction products during distillation was determined. Major resin acid impurities in tall oil fatty acids were 8,15‐pimaradien‐18‐oic acid and 8,15‐isoprimaradien‐18‐oic acid, both formed chiefly during distillation, and two secodehydroabietic acid isomers common in crude tall oils. The reactions of resin acids leading to new isomers or non‐acidic products are discussed.

Occurrence of anticopalic acid in Pinus monticola

Anticopalic acid, a labdane diterpene not previously reported in the Gymnospermae, was found to be a major resin acid in the bark and in the wood of western white pine, Pinus monticola Dougl.

Terpenoid constituents of the pocket resin from coast redwood ( Sequoia sempervirens)

The principal volatile component in the pocket resin of Sequoia sempervirens is α-pinene, while the major resin acids appear to be levopimaric and palustric acids among the five resin acids identified. Abietic acid could not be detected.