Pinus bark extract

Condensed tannins constitute more than 90 per cent of the total world production of commercial tannins (200000 tons per year) [11]. Their high reactivity towards aldehydes and other reagents renders them both chemically and economically more interesting for the preparation of adhesives, resins and other applications apart from leather tanning. The main commercial species, such as mimosa and quebracho, also yield excellent heavy duty leather. Condensed tannins and their flavonoid precursors are known for their wide distribution in nature and particularly for their substantial concentration in the wood and bark of various trees. These include various Acacia (wattle or mimosa bark extract), Schinopsis (quebracho wood extract), Tsuga (hemlock bark extract), Rhus (sumach extract) species, and various Pinus bark extract species, from which commercial tannin extracts are manufactured. 

NARDINI M, SCACCINI c, PACKER L and VIRGILI F (2000) In vivo inhibition of the activity of phosphorylase kinase, protein kinase C and protein kinase A by caffeic acid and a procyanidin rich pine bark (Pinus maritima) extract Biochimica Biophysica Acta 1474, 219-25. 

Bacillus, Klebsiella, Cornybacterium, and Pseudomonas being the most frequently observed. The capacity of these bacteria to degrade tannins, and detoxify bark chips or barks extracts, was further demonstrated with pine (Pinus maritima) (51), oak (Quercus pedonculata) and gaboon wood (Aucoumea kleneana) barks (52). The degradation of quebracho and wattle tannins was also confirmed in pure cultures (53). 

This paper is a report on preliminary studies evaluating the suitability of bark extracts from four West Coast softwood species as bonding agents for particleboard. The barks investigated include white fir (Abies concolor), ponderosa pine (Pinus ponderosa), Douglas fir (Pseudotsuga menziesii) and western hemlock (Tsuga heterophylla) ... 

These results may be compared with viscosities obtained in a similar way from conifer bark extracts which, while heterogeneous, contain polymeric pro-cyanidins or mixed polymeric procyanidins and prodelphinidins as their predominant components (2). For example, Weissman (25) reported a viscosity of 65 mPa-s for a 30% solution of the water extract from Pinus oocarpa bark, and Dix and Marutsky (26) obtained a value of 31 mPa-s for a similar solution from Picea abies bark. These viscosities are similar to those observed for the 30% procyanidin polymer solutions. They indicate that the viscosities of these bark extract solutions are dominated by the proanthocyanidins and that there is little influence from any accompanying polysaccharides-as already suggested by Weissmann (25)-in contrast to wattle extracts where gums play an important role in determining solution viscosities (7). 

Ayla (27) reported a viscosity of 65 mPa-s for a 40% solution of the bark extract from Pinus brutia. This is very much lower than that obtained for the T. cacao procyanidin polymer, even though Ayla s (27) estimate of 7-8 for the number-average degree of polymerization was apparently higher than the value of 6.1 obtained for the T. cacao polymer. However, it has recently been shown that the P. brutia polymer is actually a procyanidin-O-glucoside (28). When... 

The gluing experiments were done with commercially available starch, proteins (casein, glutin) and tannins of mimosa Acacia spp.), Pinus radiatay and quebracho (Schinopsis spp.) and with tannins extracted from the bark of spruce (Picea abies) and common pine (Pinus sylvestris). The extractions were carried out with water or organic solvents under alkali and/or sulphite conditions on a laboratory scale aiming at optimization of yield and polyphenolic extract content. After extraction, the solutions were concentrated under reduced pressure and freeze dried. One pine bark extract was modified with phenol. A summary of the tannin extracts and their properties is given in Table I. 

Virgin, F. et al., Ferulic acid excretion as a marker of consumption of a French maritime pine (Pinus maritima) bark extract. Free Radical Biol Med., 28, 1249, 2000. 

Tannin Content of Pinus pinaster Bark Extracts... 

Pimenta (Pimenta officinalis) leaf oil Pineapple (Ananas sativus) Juice Pine (Pinus palustris) oil Pine (Pinus pumilio) needle oil Pine (Pinus sylvestris) needle extract Pine (Pinus sylvestris) needle oil Pine (Pinus sylvestris) oil Pipsissewa (Chimaphila umbellata) leaves extract Pomegranate (Punica granatum) bark extract Poppyseed (Papaver somnifemm)... 

A similar climate exists for development of adhesives from Pinus radiata bark in Australia and New Zealand. A 22 ton/day bark extraction plant was built by New Zealand Forest Products Ltd. at Kinleith, New Zealand. These extracts have proved to be more difficult to use than wattle tannin due to their comparatively high molecular weight, the high viscosity of most extract preparations, their rapid rate of reaction with formaldehyde, and the often higher proportion of carbohydrate impurities. Current information (L. J. Porter, 1987) is that production of tannin by New Zealand Forest Products Ltd. has now ceased. In an attempt to make more uniform extracts with lower proportions of carbohydrates, ultrafiltration (257, 258) fractionation on Amberlite XAD-B gel (239), and fermentation (220) purifications have been investigated. Various reactions such as sulfonation and either acid- or base-catalyzed cleavage have been employed to reduce the viscosity of these extracts. A number of adhesive formulations based on P radiata bark extracts have been developed. However, technical difficulties continue to inhibit the commercial use of Pinus radiata bark extracts in wood adhesives. 

The first attempts to use wattle tannins in particleboard adhesives (114, 170) followed reports by Dalton (50, 51) on the use of Pinus radiata bark extracts as substitutes for phenol-formaldehyde resins in plywood adhesives. Even though the molecular weight of wattle tannin is comparatively low (208), solutions of bark extracts at solids contents required for adhesives (40%-58%) exhibit excessively high viscosities. High-temperature alkaline treatments reduced their viscosity, and... 

Research directed to the use of bark extracts from various species of pines has continued despite the marked reduction in prices for petroleum in the late 1970s and early 1980s. A number of new plywood adhesive formulations based on extracts of Pinus radiata have been described recently. Weissmann and Ayla (253) used sulfonated tannin extracts at 40% solids and fortified these extracts with a phenol-formaldehyde resin (Kauresin 260 produced by BASF) at levels to 10% to 50% by weight of solids. Both paraformaldehyde and hexamethylenetetramine were examined as aldehyde sources. Exterior grade plywood bonds were obtained at 10% and 30% fortifying levels. 

Dix B, Marutzky R 1984 Gluing of particleboards with tannin formaldehyde resins from bark extract of Pinus radiata. Holz Roh-Werkst 42 209- 217... 

The Orkney vole, Microtus arvalis orcadensis, removes almost no bark from seedlings of Scots pine, Pinus sylvestris, if they are treated with an extract of feces of red fox, Vulpes vulpes, even though the two species have been separated for approximately 5500 years (Calder and Gorman, 1991). 

The anthocyanin is malvidin-3,5-diglucoside (Fluka), and the tannins are a sample of leucoanthocyanins extracted from the bark of the maritime pine (Pinus pinaster). The products are not identical to the natural grape pigments nevertheless, it may be assumed that the observed facts correlate, as a first approximation, with red wine color and its changes. 

Packer, L., Rimbach, G., and Virgili, F. Antioxidant activity and biologic properties of a procyanidin-rich extract from pine (Pinus martima) bark, pycnogenol, Free Radic. Biol. Med., 27, 704—724, 1999. 

Figure 6.13 Examples of the application of normal-phase, radio-HPLC to the analysis of de novo biosynthetic pathways in bark beetles (Scolytidae). Demonstration of sex-specific de novo biosynthesis of ipsenol, ipsdienol, and amitinol through radio-HPLC analysis of pentane extracts of Porapak-trapped volatiles from (A) male and (B) female Ips paraconfusus Lanier feeding for 168 h in Pinus ponderosa and (C) male and (D) female Ips pini (Say) feeding for 168 h in Pinus jeffreyi (Seybold et al., 1995b). Demonstration of sex-specific de novo biosynthesis of frontalin through radio-HPLC analysis of pentane extracts of Porapak-trapped volatiles from (E) male and (F) female...

In contrast, Yazaki and Hillis 29) obtained a viscosity of 8,500 mPa-s for a 45% solution of the aqueous extract from Pinus radiata bark. This is almost an order of magnitude higher than that expected on the basis of the procyanidin polymer results. Viscosities of the methanol-soluble portion and the ultrafiltered portions of this extract were 500 and 90 mPa-s, respectively. The former value is about that expected for a proanthocyanidin polymer, but the latter indicates that most of the polymer has been excluded by the filter, and it further implies that molecular sizes of proanthocyanidins based on ultrafiltration measurements are often misleading. 

However, the procyanidin results are very different from those obtained by Weissmann 25) for alkaline extracts from Pinus oocarpa bark. On the basis of 30% w/w solutions at 25 °C, the water-soluble material was found to have a viscosity of 65 mPa-s, whereas, the material soluble in 1% sodium hydroxide had a viscosity of 1,294 mPa-s. In light of the results of the current study, this observation is only explicable if the viscosity of the sodium hydroxide extract is due to nontannin components. 

In Australia, Radiata pine (Pinus Radiata) is widely silvicultured and a large amount of bark is generated unused. This bark contains large amounts of polyphenols called polyflavanoids (radiata tannin) which react with formaldehyde to give high-quality water-proof wood adhesives. An effective tatmin extraction is one of the most important key technologies to produce water-proof and structural wood adhesives. It is well-known that the... 

There is a general consensus that analysis of fresh material yields results which come closest to the natural distribution pattern in plants. Since this approach is not feasible in most cases suitable preservation procedures must be employed. Advantages and disadvantages of such procedures with respect to polyphenol analysis have been reviewed by several authors [47-49]. The procedure keeping the chemical composition as close as possible to the natural state is lyophilization. A study of the extractability of proanthocyanidins in the bark of several pines (Pinus sp.) showed no difference between freshly collected samples and freeze-dried samples. On the other hand drying at room temperature resulted in an increase in extractability in one sample [50]. Increased extractability after drying at room temperature compared to fresh material has also been... 

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