G

I

Ra

BNa

b

Uc

a

ARRAA

KOATP(F

1

4

0d

ARTICLE IN PRESSModel

NDCRO-5631; No. of Pages 9

Industrial Crops and Products xxx (2011) xxx–xxx

Contents lists available at ScienceDirect

Industrial Crops and Products

journa l homepage: www.e lsev ier .com/ locate / indcrop

elationships involving several types of extractives of five nativergentine wood species of genera Prosopis and Acacia

enedetto Pizzoa,∗, Carolina L. Pomettib, Jean-Paul Charpentierc,athalie Boizotc, Beatriz O. Saidmanb

CNR-IVALSA, via Madonna del Piano, 10, I-50019 Sesto Fiorentino, FI, ItalyLaboratorio de Genética, Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales,niversidad de Buenos Aires, Intendente Güiraldes s/n, Pabellón 2, Ciudad Universitaria (1428), Buenos Aires, ArgentinaINRA, GENOBOIS, 2163 Avenue de la Pomme de Pin, CS 40001 ARDON, F-45075 Orleans Cedex 2, France

r t i c l e i n f o

rticle history:eceived 11 November 2010eceived in revised form 7 February 2011ccepted 8 February 2011vailable online xxx

eywords:rganic extractivesqueous extractivesannic contenthenolic compounds−)-Mesquitollavanols

a b s t r a c t

The relationships existing among the values obtained when extracting the wood of four Argentineanspecies of Prosopis (P. alba, P. kuntzei, P. nigra, and P. ruscifolia) and one of the Acacia (A. aroma) byseveral procedures were evaluated and discussed. The used methods were: extraction in toluene/ethanoland hot water; determination of tannic and non-tannic content; measurement of phenolic compounds.Additionally, liquid chromatography (HPLC) was also used in order to quantitatively evaluate the contentof (−)-mesquitol, a relatively unusual flavonoid (flavanol type). The total amount of Oxidation Productswas also measured. They result from oxidation and polymerization processes of phenolic compoundsoccurring during heartwood formation, and were not separated during chromatographic analysis. Dataevidenced a linear trend (R2 = 0.970) between organic and tannic extractives of all species, and a similarone (R2 = 0.927) between total phenols and tannic (or organic) extractives in the case of heartwood ofProsopis species. Interestingly, for sapwood very different values of organic extracts, tannic content orOxidation Products type compounds were measured in spite of a similar amount of phenolic substances.Moreover, the various species presented the same peaks in chromatograms, thus evidencing the chemicalsimilarity of compounds but a different quantity between heartwood and sapwood and also among thevarious species. The observed similarity implied that the various methods of extraction did not reallyextract only a single class of substances, and that great care must be adopted when using some specificprocedures for extractions.

Furthermore, the existing relationships between extractives and selected technological properties,namely specific volumetric shrinkage coefficient (BSvol) and natural durability (evaluated in terms of massloss after fungal attacks in laboratory conditions), were given. It appeared that in heartwood BSvol waswell correlated to organic extractives (R2 = 0.984), thus evidencing the microimpregnation of cell wallsby extractives, but the fitting quality of the correlation was dependent on the type of extractives used.

2

Analogously, a good relationship between mass loss and phenolic compounds existed (R = 0.764), and inthis case the value of R2 was even more dependent on the considered extracts. Moreover, the availabilityof quantitative data on several Prosopis species allowed to consistently evaluate the bioactivity of (−)-mesquitol on the resistance against fungal attack, and the logarithmic form of the relationship betweenmass loss and (−)-mesquitol content suggested a direct fungicidal activity of this compound. On the otherhand, data also evidenced that neither phenolic compounds nor (−)-mesquitol can be considered as the

r able

unique and definite facto

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

. Introduction

The genus Prosopis (Leguminosae, Mimosoideae) involves about4 woody species distributed in arid and semi-arid regions of

∗ Corresponding author. Tel.: +39 055 522 5623; fax: +39 055 522 5507.E-mail address: pizzo@ivalsa.cnr.it (B. Pizzo).

926-6690/$ – see front matter © 2011 Elsevier B.V. All rights reserved.oi:10.1016/j.indcrop.2011.02.003

to determine the durability of the considered species.© 2011 Elsevier B.V. All rights reserved.

Americas, Africa and Asia. The world centre of biodiversity ofthis genus is located in Argentina, where 28 species are found, ofwhich 13 are endemic (Burkart, 1976). The genus Acacia (Legumi-

several types of extractives of five native argentine wood species of011.02.003

nosae, Mimosoideae) has a pantropical distribution and comprisesapproximately 1450 species (Luckow, 2005), of which 21 are nativeto Argentina (Cialdella, 1984, 1997). Most of the species of both gen-era are considered multipurpose trees and shrubs by FAO (1988)because almost all their biomass can be used. Many of these two

ING

I

2 s and

gisnPcadflb

Fsfaatte

istfshbeed

earflVwop(ibtb2jao

P(eSndts

tePaare

ARTICLEModel

NDCRO-5631; No. of Pages 9

B. Pizzo et al. / Industrial Crop

enera are used in reforestation programs because they fulfil anmportant role against desertification of eroded soils. In addition,ome species are used to produce forage, human food, charcoal, fur-iture, medicinal substances, alcohol and dyes (Karlin et al., 1997).rosopis and Acacia wood has also been used extensively for char-oal and building materials in Argentina (Tortorelli, 1956; D’Antonind Solbrig, 1977). The lumber of Prosopis species has exceptionalimensional stability. This characteristic results in furniture andooring with much less tendency to warp and twist than that cane obtained from other fine woods.

Prosopis and Acacia species also have potential for industrial use.or instance, wood of these species is rich in extractable substancesuch as gums and tannins. These latter have economic importanceor the leather industry of both developing (China, India and Brazilre the biggest shoe producers in the world, Abicalcados, 2009)nd the developed countries (only Italy in the EU processed morehan 170 millions of m2 of leather in 2007, IPPC, 2009). Fromhis perspective, Prosopis and Acacia could represent new and lessxpensive source of tannins (Readel et al., 2001).

Extractable substances (in terms of both quality and amount)nfluence several properties of lumber, including aesthetical onesuch as colour and colour fading and also several characteristics ofechnological interest. Shrinkage characteristics are very importantor industrial use because they affect the behaviour of lumber uponeasoning or artificial drying. In the case of the species consideredere, recent studies demonstrated that extractive content apprecia-ly influences the dimensional stability of Prosopis kuntzei (Pomettit al., 2009). The heartwood of this species had a lower thanxpected specific volumetric shrinkage in relation to its density,ue to the exceptionally large amount of extractable substances.

Moreover, knowledge of the existing relationships betweenxtractives and mass loss after fungal attack has a twofolddvantage: (1) a better understanding of factors affecting natu-al durability, thus facilitating research for more environmentalriendly preservation products, and (2) potentially reducing theong time normally needed for laboratory decay tests. Harju andenäläinen (2006) even proposed replacing in vitro decay testsith a chemical assay able to evaluate phenolic compounds, in

rder to more rapidly assess wood durability. It has been shownreviously that a direct relationship exists between durabilityevaluated in terms of resistance to mass loss during fungal attackn laboratory conditions) and content of phenolic compounds, foroth Prosopis and Acacia aroma (Pometti et al., 2010). However, inhat case neither organic nor aqueous extractives exhibited similarehaviour. For Prosopis africana an effect of gums (Gérardin et al.,004) on durability also was hypothesized, whereas for Prosopis

uliflora resistance to fungal and termite attack was hypotheticallyttributed to (−)-mesquitol, a flavanol type compound (flavan-3-ls) present in heartwood extract (Sirmah et al., 2009a).

Studies concerning the technological characterisation ofrosopis wood are becoming more common in scientific literatureGérardin et al., 2004; Carrillo et al., 2008; Sirmah et al., 2008; Paest al., 2009; Pometti et al., 2009, 2010; Sirmah et al., 2009a, 2009b;cholz et al., 2010). Most of the properties considered depend sig-ificantly on the amount and type of extractives present. However,ifferent extraction procedures give quite different results, both inerms of type and amount of extractable substances and this canubstantially affect all evaluations.

The aim of this work was first to evaluate and discuss rela-ionships existing among several procedures of determining thextractive content of four Argentinean species of Prosopis (P. alba,

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

. kuntzei, P. nigra, and P. ruscifolia) and one of the Acacia (A.roma), and secondly to evaluate relationships between extractivemount and selected technological properties (shrinkage and natu-al durability). To accomplish this purpose the amount of differentxtractives, such as toluene/ethanol and hot water extracts, tan-

PRESSProducts xxx (2011) xxx–xxx

nic and non-tannic substances and total phenolic compounds, wasdetermined. Liquid chromatography (HPLC) measurements werealso performed, in order to quantify (−)-mesquitol on the one handand unidentified compounds on the other. Finally, the relation-ships existing between extractives and shrinkage properties andbetween extractives and durability of the species considered weregiven. Furthermore, the effect of (−)-mesquitol on natural durabil-ity of these species was also evaluated.

2. Materials and methods

2.1. Sampling of wood material

Four species of the genus Prosopis and one species of Acacia(Leguminosae; Mimosoideae) were used. The species were: P. albaGriseb., P. kuntzei Harms., P. nigra Griseb., P. ruscifolia Griseb. andA. aroma Hook et Arn. Wood sample discs were cut 5–6 cm thickand no more than 15 cm in diameter from wood obtained at breastheight. All of the species came from Santiago del Estero province,República Argentina, and were cut in 2006. Three trees were usedfor each species except for P. ruscifolia, for which two trees wereused. P. nigra and P. kuntzei samples came from a natural popula-tion located at Establecimiento Yanda, Robles, Department of SanMartín. P. ruscifolia samples came from a natural setting locatedat Establecimiento Agroten S.A., in Brea Pozo, Department of SanMartín. A. aroma samples came from a natural population, located atRuta provincial no. 18, Robles, Department of San Martín. Samplesof P. alba came from a plantation located at Estación experimentalFernández, in Fernández, Department of Robles. Trees from naturalpopulations were selected as representatives of the whole popula-tion. When possible those with a straight trunk were chosen.

Samples for extractions were taken from heartwood and sap-wood, respectively. Depending on the type of extraction, the woodpowder was processed in different ways (see Sections 2.2–2.5). Atotal of 20–100 g was obtained from each species considered.

2.2. Determination of organic and aqueous extractives

Samples of sapwood and heartwood of the five species weremilled in a Wiley mill (Thomas Scientific, Swedesboro, NJ) to obtaina 40–60 mesh meals (approximately 0.2–0.4 mm). Analyses werecarried out in duplicate, each time on approximately 5 g of sievedmaterials.

The amount of extractives was measured according to Tappistandards (1996), but a slightly modified version of T204 was used.The solvents utilised for the extractions were: (1) 1:2 (v/v) mixtureethanol 95%: toluene and (2) demineralised water. The same sam-ples first extracted with the mixture ethanol–toluene were thenextracted with demineralised water. All samples were extractedfor successive periods of 30 cycles (about six cycles per hour) ina Soxhlet extractor. Following the extraction steps, the flasks con-taining the collected extractives were first vacuum-dried and thenoven-dried to constant weight at 103 ◦C. The flasks were afterwardscooled and weighed, and the amount of extractives calculated as apercentage of the initial anhydrous mass.

2.3. Determination of tannic and non-tannic content

Measurements were carried out on approximately 20 g of milledmaterial sieved to collect the fraction between 85 and 200 �m.

several types of extractives of five native argentine wood species of011.02.003

Wood meal was extracted with 200 ml of boiling distilled water(by maintaining it in a bath at 100 ◦C) for 90 min and the solutioncollected in a separate flask. This operation was repeated 5 times.Finally, the indirect tannin analysis was carried out by using theprocedures described in ISO/DIS 14088 (2009). According to this

ING

I

s and

sfpmtam

2c

(f2

5tia2pam

CeCwbsgaa

iSlb(p(mcai

2

lc(111a1batc(h

m

ARTICLEModel

NDCRO-5631; No. of Pages 9

B. Pizzo et al. / Industrial Crop

tandard method, the percentage of tannins was obtained by dif-erence between the percentage of total soluble substances and theercentage of non-tannic content. This latter was determined gravi-etrically by detanning part of the analytical solution by fixing

he absorbent compounds in low-chromed hide powder. All thesemounts were calculated as a percentage of the initial anhydrousass of wood.

.4. Extraction and quantitative measurement of soluble phenolicompounds

Material for phenolic analysis was taken from 3 to 5 zonesdepending on the availability) on the same ray of a wood disk,rom sapwood towards inner heartwood. From each zone, a piecemm in thickness was milled into particles of 100 �m diameter.

The soluble phenolic compounds were extracted twice from0 mg of dry wood powder in 2 ml of an acetone: water solu-ion (8:2, v/v) containing 10−4 M 6-methoxyflavone (Sigma) asnternal standard. The mixture was sonicated for 45 min, thengitated for 45 min before being centrifuged at 16,000 rpm for0 min. All the steps were carried out at 4 ◦C. Then, 500 �L ofooled supernatants was removed and dried under vacuum usingSpeed-Vac system. The dry residue was diluted in 250 �l ofethanol.After that, total polyphenols were estimated by the Folin-

iocalteu method adapted (Boizot and Charpentier, 2006). Phenolicxtract (20 �l) diluted in 80 �l of ultra-pure water, 500 �l of Folin-iocalteu’s phenol reagent 2N (Sigma, diluted 10 times in ultra-pureater) and 400 �l of a 75 g/L Na2CO3 solution were mixed and incu-

ated for 5 min at 40 ◦C. The absorbance at 735 nm was measuredpectrophotometrically and the results were expressed in mg ofallic acid equivalent (GAE) per gram dry weight. Calibration waschieved with gallic acid aqueous solutions (0–20 �g/mL) and thenalyses for calibration were carried out in duplicate.

Considering the related presence of several flavanol compoundsn the extracts of Prosopis (Sirmah et al., 2009a; Sirmah et al., 2009b;cholz et al., 2010), these compounds were also extracted and col-ectively quantified. The quantification of flavanols was carried outy a colorimetric method using 4-dimethylaminocinnamaldehydeDMACA – Sigma) as chemical reagent (Treutter, 1989). Fifty �l ofhenolic extract, 930 �l of methanol and 20 �l of DMACA solution100 mg DMACA in 10 ml of 1.5 M methanolic sulfuric acid) were

ixed and incubated for 2 h at room temperature. The flavanolontent was determined spectrophotometrically at 630 nm usingstandard curve based on catechin (0–15 �g mL−1) and expressed

n mg of catechin equivalent (CE) per gram dry mass.

.5. Liquid chromatographic analysis

After centrifugation (17,000 rpm for 3 min), 15 �l of the pheno-ic compounds extracted as reported in Section 2.4 was separated,haracterized and quantified by HPLC on a 32 Karat systemBeckman Coulter, France) using a 250 mm × 4 mm Licrospher00RP-18e column (5 �m) (Merck, Germany), at a flow rate ofmL/min with the following linear elution gradient: 0–15 min:5% Solvent B (methanol/acetonitrile, 50:50, v/v) in Solvent A (1%cetic acid in ultra-pure water); 15–20 min: 15–100% B; 20–25 min:00% B; 25–27 min: 100–15% B. Compounds were characterisedy their elution time and their UV absorption spectrum (dioderray: 230–430 nm). Only the identification of (−)-mesquitol (2,3-rans-3′,4′,7,8-tetrahydroxyflavan-3-ol) was achieved, by using

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

o-chromatography with a standard supplied by Prof. P. GérardinUniversity of Nancy, France), extracted, isolated and purified fromeartwood of P. juliflora.

Oxidation Products are very difficult to separate by the HPLCethod chosen for this study. Consequently, their total amount was

PRESSProducts xxx (2011) xxx–xxx 3

determined as the sum of peak areas detected in the 20–23 minrange of retention times in chromatograms.

Quantitative determination of phenolics was performed at280 nm and expressed in mg of 6-methoxyflavone (MOF) equiv-alent per gram dry weight.

2.6. Measurement of selected technological properties

The shrinkage properties and the resistance against rot fungiattacks during laboratory tests were considered with the aim of ver-ifying in which way the observed differences among the extractivesaffected these characteristics. More specifically, the specific volu-metric shrinkage coefficients (BSvol), representing the volumetricshrinkage coefficient per unit moisture content, were consideredas representative of shrinkage properties. Values of BSvol weretaken from Pometti et al. (2009), considering that the same speci-mens were used both in that and the present case. However, whilstthe heartwood BSvol values were available for all species, the datafor sapwood was available only for P. kuntzei. Therefore, only theextractive amount for these zones was considered during the eval-uations.

Concerning durability, data for mass loss due to attack of Corio-lus versicolor in laboratory tests were analysed. Values for mass losswere taken from Pometti et al. (2010), considering that similar sam-ples were used in both cases. More details about the experimentalprocedure followed can be found in Pometti et al. (2010).

3. Results and discussion

3.1. Determination of extractives

Considerable amounts of extracts were found in heartwoodsof P. kuntzei, P. alba and A. aroma. In these species the content oforganic extractives was greater than 15% of the anhydrous mass,whereas tannic substances were present in quantities as high as8% of dry mass for A. aroma and even more for the two Prosopisspecies mentioned (17% and 11% respectively) (Table 1). Moreover,heartwood of P. kuntzei and P. alba was particularly rich in pheno-lic compounds and flavanols, although flavanols were elevated inP. ruscifolia as well. Sapwood of P. alba, P. nigra and A. aroma alsocontained a large amount of organic extractives, approximately 9%of the dry mass.

Similar results to ours were found by Goldstein and Villareal(1972), who extracted ground mesquite heartwood (Prosopis spp.)using the organic-solvent/hot-water sequence and a total of 18% ofextractives was removed. Analogously, Wiley (1977) obtained anamount of 13.44% of extractives in P. juliflora heartwood with a sim-ilar procedure, and Hillis (1962) reported a 15.5% loss in weight forground mesquite extracted with water. Moreover, Tortorelli (1956)reported a value of 10–12% tannic substances for P. alba, whichagrees with our measurements (11.01%).

The results established that the content of organic extractivesin heartwood was generally higher than in sapwood, the greatestdifferences being observed for P. alba (16.59% and 9.94% respec-tively) and for P. kuntzei (20.83% and 5.13% respectively). Only forP. nigra they were approximately equal (8.18% in heartwood and9.11% in sapwood). Heartwood was also richer than sapwood intannic substances and in phenolic compounds. In the latter case,the differences were more than one order of magnitude for P. alba(128.09 mg GAE/g and 6.31 mg GAE/g, respectively) and P. kuntzei

several types of extractives of five native argentine wood species of011.02.003

(213.83 mg GAE/g and 9.99 mg GAE/g, respectively) (Table 1). Thefact that sapwood contained a smaller amount of polyphenols thanheartwood was expected, as colour change (in general, duraminiza-tion) in stems is believed to be associated with enzymatic processesinvolving polyphenoloxidases or peroxidases, using storage mate-

ARTICLE IN PRESSG Model

INDCRO-5631; No. of Pages 9

4 B. Pizzo et al. / Industrial Crops and Products xxx (2011) xxx–xxx

Table 1Quantity of the various types of extractives. (S): sapwood; (H): heartwood. Percentages are based on anhydrous weight; mg GAE/g d.m. = mg of gallic acid equivalent pergram dry mass; mg CE/g d.m. = mg of catechin equivalent per gram dry mass. Standard deviation in brackets.

Species Organicextractives (%)

Aqueousextractives (%)

Tannic content(%)

Non-tanniccontent (%)

Phenoliccompounds(mg GAE/g d.m.)

Flavanols(mg CE/g d.m.)

P. alba (S) 9.94 (2.49) 10.65 (3.33) 5.77 (0.13) 4.49 (0.23) 6.31 (–) 0.05 (0.004)P. alba (H) 16.59 (2.49) 2.91 (0.92) 11.01 (2.05) 3.90 (0.16) 128.09 (3.47) 1.31 (0.181)P. kuntzei (S) 5.13 (0.01) 2.24 (0.48) 0.51 (0.45) 5.05 (0.23) 9.99 (–) 0.31 (0.022)P. kuntzei (H) 20.83 (0.16) 2.93 (0.06) 17.10 (2.39) 4.25 (0.47) 213.83 (0.50) 15.47 (0.165)P. nigra (S) 9.11 (1.98) 5.17 (0.18) 2.70 (0.17) 5.28 (–) 10.22 (–) 0.08 (0.005)P. nigra (H) 8.18 (1.52) 3.49 (0.29) 4.46 (1.15) 1.89 (0.26) 82.51 (3.58) 0.49 (0.370)

(0.78) 4.82 (1.39) 7.42 (–) 0.09 (0.047)(1.20) 3.60 (0.40) 27.10 (6.58) 1.19 (0.154)(0.77) 4.50 (–) 10.11 (–) 0.05 (0.001)(0.37) 8.27 (0.16) 50.19 (11.36) 0.13 (0.0031)

r1

th±wPat(

winta

pee4bs

nmwv

opco

TQO

P. ruscifolia (S) 4.78 (0.89) 4.09 (2.81) 2.91P. ruscifolia (H) 5.90 (0.85) 3.15 (1.45) 3.64A. aroma (S) 8.68 (2.46) 6.73 (1.23) 1.69A. aroma (H) 16.59 (0.32) 8.76 (0.84) 8.14

ials as metabolites for the formation of polyphenols (Shah et al.,981; Magel et al., 1994).

Sapwood contained more (or an equal amount) aqueous extrac-ives than heartwood. The difference between sapwood andeartwood was 7.74% (in absolute terms) for P. alba, but within2% for the other species. On the other hand, non-tannic contentas almost the same between heartwood and sapwood, except for

. nigra (in which sapwood was richer in non-tannic content, 5.28%gainst 1.89%) and A. aroma (in which, instead, the sapwood con-ained a smaller amount of non-tannic content, 4.50% versus 8.27%)Table 1).

Finally, except for P. kuntzei and A. aroma, heartwood and sap-ood had a nearly equivalent amount of total extractives, evaluated

n terms of both organic plus aqueous extracts and of tannic pluson-tannic substances: this difference was of the order of ±4% forhe other species, whereas it was of the order of 16% for P. kuntzeind of 10% for A. aroma (all values are in absolute terms).

Sapwood generally contained a larger amount of organic as com-ared to aqueous extractives (from 22.5% to 56% more of the organicxtractives), although for P. alba and P. ruscifolia the amount of bothxtractives was almost equal (9.94% versus 10.65% for P. alba and.78% versus 4.09% for P. ruscifolia). Instead, sapwood was apprecia-ly richer in non-tannic content, and only in P. alba was the amountimilar (non-tannics 4.5%, tannics 5.8%).

Additionally, the heartwood contained a larger quantity of tan-ic as compared to the non-tannic substances (from 58% to 75%ore of the tannic substances), except for P. ruscifolia and A. aromahich were approximately the same (3.64% versus 3.60% and 8.14%

ersus 8.27%, respectively).

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

Therefore, the various analyses allowed making evaluations notnly on the quality, but also on the quantity, of extractives, thusermitting investigation of relationships among the various pro-edures of extracting wood. A linear trend (R2 = 0.970) could bebserved when the tannic extractives were plotted versus the

able 2uantity of the various peaks revealed by the HPLC analysis. All the values for peaks arexidation Products type compounds. S = sapwood, H = heartwood. Standard deviation in b

Mesquitol (retention time: 9.14 min) OP (

P. alba (S) 0.118 (0.094) 1.7P. alba (H) 5.105 (0.436) 13.0

P. kuntzei (S) 0.053 (0.002) 2.4P. kuntzei (H) 5.866 (1.350) 15.1

P. ruscifolia (S) 0.030 (–) 0.8P. ruscifolia (H) 0.340 (0.102) 4.3

P. nigra (S) 0.126 (0.001) 3.0P. nigra (H) 0.518 (0.247) 13.0

A. aroma (S) 6.82 × 10−4 (9.65 × 10−4) 2.8A. aroma (H) 0.182 (0.059) 10.5

Fig. 1. Relationship between tannic and organic extracts. The values of Acacia werenot considered for the linear regression.

organic ones (Fig. 1), and the slope of the straight line was lowerthan 1 (specifically 0.88). Therefore, generally larger amount oforganic extractives were obtained in comparison to the tannicones. Although tannins are organic compounds of medium polarity(Fengel and Wegener, 1984), this proportionality was not neces-sarily expected a priori because in our case tannins were extracted

several types of extractives of five native argentine wood species of011.02.003

in hot water and not in organic solvents. This linear relationshipsuggested that all species had similar compounds in proportionalquantity. Similarity of composition among the various species wasalso confirmed by HPLC analysis (Section 3.2).

expressed in mg equiv. methoxyflavone/g dry mass. OP represents the sum of therackets.

retention time: 20–23 min) Sum of other unidentified compounds

4 (0.842) 0.39 (0.094)1 (2.233) 6.07 (0.311)

7 (0.220) 0.82 (0.002)5 (3.911) 15.18 (1.195)

5 (–) 0.44 (–)9 (0.435) 1.82 (0.156)

5 (0.073) 0.75 (0.001)3 (1.559) 2.07 (0.144)

6 (0.053) 2.95 (0.019)3 (2.667) 11.73 (2.548)

ARTICLE IN PRESSG Model

INDCRO-5631; No. of Pages 9

B. Pizzo et al. / Industrial Crops and Products xxx (2011) xxx–xxx 5

Fig. 2. HPLC chromatograms (absorbance 280 nm) of three species (Prosopis alba,Ppr

3

iovTasafio1amwPst

(Table 2).Moreover, chromatographic analysis confirmed that wood

extracts of the Prosopis species studied were composed of severalflavanol compounds in addition to (−)-mesquitol. In this case, the

rosopis kuntzei and Acacia aroma) heartwood extracts. The retention time of eacheak is reported. MOF = 6-methoxyflavone as internal standard. The dashed lineepresents the elution gradient.

.2. Liquid chromatographic analysis

Fig. 2 shows some examples of chromatograms obtained dur-ng the HPLC analysis. The positions (in terms of retention times)f (−)-mesquitol, Oxidation Products type compounds (not indi-idually identified) and of other unidentified peaks are shown.he various species exhibited the same peaks in chromatograms,lthough some compounds differed quantitatively among thepecies considered (data not shown). As already evidenced by othernalyses, P. kuntzei appeared to be particularly rich in quanti-ed compounds, with a total sum (i.e., heartwood and sapwood)f 39.5 mg equiv. MOF/g (P. alba 26.4 mg equiv. MOF/g, P. nigra9.5 mg equiv. MOF/g, P. ruscifolia 7.9 mg equiv. MOF/g, whereas A.roma had 28.2 mg equiv. MOF/g) (Table 2). Moreover, as expected,ost substances increased appreciably from sapwood to heart-

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

ood. The increase was of one order of magnitude for Oxidationroducts type compounds and even more for the unidentifiedubstances of P. kuntzei and P. alba (18 and 15 times respec-ively).

Fig. 3. UV absorbance spectrum of (−)-mesquitol compared with that one of thecatechin. Spectra were obtained during the chromatographic elution in the elutionsolvent (15% mixture of methanol/acetonitrile in water, as specified in Section 2.5).

(−)-Mesquitol was the most abundant compound in the woodextract of two species (P. alba and P. kuntzei). This was also observedin P. juliflora (Sirmah et al., 2009b), the species from which (−)-mesquitol was originally isolated.

It is also interesting to observe that A. aroma possessed the samesubstances as the Prosopis species examined, with quantitative dif-ferences only for a few components (not shown). For instance,the heartwood of A. aroma contained from approximately 2–30times less (−)-mesquitol than the Prosopis species here studied

several types of extractives of five native argentine wood species of011.02.003

Fig. 4. Relationships between phenolic compounds and organic extractives.GAE = gallic acid equivalent. The values of Acacia were not considered for the lin-ear regression. Circles refer to the different heartwood (solid circles) and sapwood(open circles) Prosopis samples. Squares refer to Acacia samples, both sapwood andheartwood.

ARTICLE ING Model

INDCRO-5631; No. of Pages 9

6 B. Pizzo et al. / Industrial Crops and

Fig. 5. Relationship between Oxidation Products type compounds (OP) and phenoliccompounds. GAE = gallic acid equivalent; MOF = 6-methoxyflavone. Circles refer totS

aebr(

woldesbs

FOa

he different heartwood (solid circles) and sapwood (open circles) Prosopis samples.quares refer to Acacia samples, both sapwood and heartwood.

ttribution was made on the basis of UV absorption spectra of cat-chin, the representative compound of this family of flavonoidsut no other precise identification of these compounds was car-ied out. The similarity of UV absorption spectra of catechin and−)-mesquitol is shown in Fig. 3.

Concerning the substances analysed by HPLC, no relationshipsere found between single compounds and the various methods

f extraction used (organic extractives, tannic content and pheno-ic compounds). This fact, together with the similarity of the peaks

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

etected in chromatograms, implies that the various methods ofxtraction used did not really extract only a specific class of sub-tances. Therefore, the methods used were not selective as mighte expected, and hence great care must be adopted when usingpecific procedures for extractions.

ig. 6. Relationship between specific volumetric shrinkage coefficient (BSvol) and phenon (b) the dash-dot-dot line refers to organic and the continuous one to tannic extractiveroma were not considered for the linear regression. Open symbols refer to the different

PRESSProducts xxx (2011) xxx–xxx

It is also interesting to note that, whilst in the case of the heart-wood of Prosopis species, a linear trend could be observed betweentotal phenols and tannic or organic extractives (R2 = 0.927), thesame was not true in the case of sapwood, where very differentvalues of organic extractives were measured in spite of a simi-lar amount of phenolic compounds (Fig. 4). The proportionality inheartwood between tannic substances and phenolic compoundswas expected because tannins are polyphenols (Rice, 1983); indeed,a similar occurrence was also observed for other lignocellulosicmaterials by Vázquez et al. (2009). On the other hand, the invarianceof the phenolic content in sapwood, differently from the organic ortannic extracts, was also observed for the Oxidation Products typecompounds (Fig. 5). Moreover, Oxidation Products varied in sap-wood of approximately 3.5 times from its minimum (0.85 mg equiv.MOF/g for P. ruscifolia) to its maximum (3.05 mg equiv. MOF/gP. nigra) and of the same ratio (15.15 mg equiv. MOF/g versus4.39 mg equiv. MOF/g) in heartwood (Table 2). Oxidation Productsresult from processes of oxidation and polymerisation of phenoliccompounds occurring during heartwood formation due to cellulardecompartmentalisation (Hillis, 1987; Magel, 2000). These resultsindicated that a different distribution of polyphenols among thevarious species (including A. aroma) could be suggested: the phe-nolic fraction was proportionally richer in Oxidation Products insapwood, whereas it was proportionally richer in other substanceswhen high values of phenolic extracts were obtained. Finally, noparticular trends were observed in the case of flavanols.

3.3. Relationships with selected technological properties

For all Prosopis species here considered, a correlation existedbetween BSvol and the various extractives (Fig. 6a and b). A directdependence was already observed between volumetric shrinkageand total extractives content for mahogany (Taylor et al., 2008) andfor several tropical hardwoods (Hernández, 2007). In our case, alinear relationship was observed for Prosopis heartwood, whereasthe available values for P. kuntzei sapwood and for Acacia wereout of that trend. The direct relationship between shrinkage prop-erties and extractive content demonstrated that in heartwood a

several types of extractives of five native argentine wood species of011.02.003

great part of these substances impregnated cell walls. In contrast,in sapwood, the extractives contributed in a limited way in deter-mining shrinkage properties because they are mostly located onparenchymous cells or form coatings on cell walls and pits (Hillis,1971; Taylor et al., 2002). Interestingly, a different quality in the

lic compounds (a) and between BSvol and both organic and tannic extractives (b).s. GAE = gallic acid equivalent. A.a. = Acacia aroma. Values of sapwood and of Acaciaheartwood Prosopis samples. Data of BSvol were taken from Pometti et al., 2009.

ARTICLE IN PRESSG Model

INDCRO-5631; No. of Pages 9

B. Pizzo et al. / Industrial Crops and Products xxx (2011) xxx–xxx 7

Table 3Values of coefficients a and b for the power law fitting curves (y = axb) between massloss and the amount of the various extractives. The value of R2 is also reported.

a b R2

fiwifTecacsd

awendldbS(lrcHtipa

ttP

Fig. 8. Relationship between mass loss after attack by Coriolus versicolor in labo-ratory decay tests and (−)-mesquitol amount. The fitting equation is: y = −5.641

F(s

Phenolic compounds 60.739 −0.721 0.764Organic extractives 81.090 −1.152 0.330Tannic content 14.774 −0.635 0.393

tting curves was observed in the plot of BSvol values for heart-ood versus the various extractive amounts. In fact, R2 was 0.984

n the case of organic extractives, whereas it was 0.972 and 0.871or tannic substances and for phenolic compounds, respectively.herefore, the predictive ability was appreciably better for organicxtractives. This is due to the non-specificity related to the pro-edure used for extraction in organic solvents (both slightly polarnd apolar substances were extracted). On the other hand, in thease of A. aroma, which belonged to a different genus, the relation-hip valid for Prosopis species were not applicable because of theifferent anatomical aspects that have to be taken into account.

Concerning the correlation between durability and extractives,good relationship between mass loss and phenolic contentas observed when values for the heartwood of P. kuntzei were

xcluded (Fig. 7a), as already observed by Pometti et al. (2010). Phe-olic extractives are known to be the main reason for the naturalurability of lignocellulosic materials, with free phenolic groups of

ignin acting as antioxidants (Schultz and Nicholas, 1997). A directependence between mass loss and total phenolics has alreadyeen observed for other species: a linear relationship was found incots pine (Pinus sylvestris L.) heartwood by Harju and Venäläinen2006) during in vitro decay tests with Coniophora puteana and inarch (Larix sp.) heartwood by Gierlinger et al. (2004) during labo-atory decay tests with both C. puteana and Poria placenta. In ourase, the best fit was obtained with a power law, y = axb (R2 = 0.764).owever the same relationship was not evident if organic extrac-

ives (R2 = 0.330) or tannic content (R2 = 0.393) were considerednstead of phenolic compounds (Fig. 7b and Table 3). These exam-les clearly indicate how choosing different extractives can give

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

ppreciably different results in terms of predictability.Additionally, present data permitted quantitative discussion of

he hypothesis formulated in the literature (Sirmah et al., 2009a)hat (−)-mesquitol plays a role in determining the durability ofrosopis species. When (−)-mesquitol content was plotted versus

ig. 7. Relationship between mass loss after attack by Coriolus versicolor and phenolic comb) the dashed line refers to tannic and the solid one to organic extractives. GAE = gallic aciapwood and heartwood) samples. Solid symbols refer to Acacia (both sapwood and hear

log(x) + 20.859. MOF = 6-methoxyflavone. Open symbols refer to the differentProsopis (both sapwood and heartwood) samples. Solid symbols refer to Acacia (bothsapwood and heartwood) samples.

mass loss, a logarithmic relationship was observed (Fig. 8). As forphenolic compounds, the data considered included both sapwoodand heartwood of A. aroma and excluded heartwood of P. kuntzei.On the other hand, if points related to A. aroma were taken out of thegraph, the fit became less accurate (R2 = 0.696, graph not shown),suggesting that the activity of (−)-mesquitol was independent ofthe species considered. Moreover, the logarithm form of the rela-

several types of extractives of five native argentine wood species of011.02.003

tionship between mass loss and (−)-mesquitol content implied thatthe effectiveness of this compound against wood destroying fungiwas limited to a certain limit, that is, the substance in excess didnot play a substantial role. In fact, mass loss of P. nigra heartwood(mesquitol 0.518 mg equiv. MOF/g) was 1.5% whereas that of P. alba

pounds (a) and between mass loss and both organic and tannic extractives (b). Ond equivalent. A.a. = Acacia aroma. Open symbols refer to the different Prosopis (bothtwood) samples. Data of mass loss were taken from Pometti et al., 2010.

ING

I

8 s and

h

mcmaMote

aspts

tod(f

4

Pttaetai(ctis

tvttcdawiopcwnp

ocf

A

NT

ARTICLEModel

NDCRO-5631; No. of Pages 9

B. Pizzo et al. / Industrial Crop

eartwood (mesquitol 5.105 mg equiv. MOF/g) was 2.4%.The logarithmic relationship between mass loss and (−)-

esquitol content also suggested a direct fungicidal activity of thisompound, considering that the same type of dependence is nor-ally observed between fungal growth and concentration of an

ntifungal agent in a medium (Amborabé et al., 2002; Zabielska-atejuk, 2005). The microdeposition of extractives in cell walls, as

bserved in Section 3.3, also confirmed this occurrence because inhis case wood becomes less attractive to decay organisms (Taylort al., 2002).

Interestingly, if flavanols were plotted versus mass loss (oncegain excluding data of the heartwood of P. kuntzei), the relation-hip was appreciably worse than for (−)-mesquitol (the value of R2

assed from 0.745 to 0.330, graph not shown). This fact confirmedhe specific bioactivity of this compound in comparison with theum of flavanols.

The behaviours shown in Figs. 7 and 8 demonstrated the posi-ive effect of (−)-mesquitol and of the whole phenolic compoundsn durability. However, the circumstance that, in both cases, dataid not fit for the heartwood of P. kuntzei indicated that neither−)-mesquitol nor phenolic compounds are the unique and definiteactor able to determine the durability of considered species.

. Conclusions

Results obtained with different types of extractives of fourrosopis and one Acacia species indicated that heartwood ofhese species is richer in organic, tannic and phenolic compoundshan sapwood, which contained generally more (or an equalmount) aqueous extractives and non-tannic compounds. How-ver, heartwood and sapwood had nearly equivalent amounts ofotal extractives. Moreover, as evidenced by HPLC analyses, fromqualitative perspective, the various species had the same peaks

n the chromatograms, indicating a similar type of compoundsalthough the amounts of each were different among the speciesonsidered). This fact implied that the various methods of extrac-ion used did not extract only a specific class of substances, and alsondicated that great care must be adopted when using repeatedlypecific procedures for extractions.

Concerning relationships between extractives and selectedechnological properties of the wood, it appeared that the specificolumetric shrinkage coefficient, BSvol, was strongly correlatedo the concentration of organic extractives, and that a good rela-ionship between mass loss (after durability tests in laboratoryonditions) and phenolic compounds also existed. However, theifferent ways of evaluating extractable compounds appreciablyffected predictability, considering that both relationships becameorse for the other extraction procedures. Moreover, the availabil-

ty of data for several Prosopis species permitted the evaluationf the hypothesis formulated in the literature that (−)-mesquitollays a role in natural durability of these species. Our resultsonfirmed the bioactivity of (−)-mesquitol, although this activityas limited to a certain threshold, after which the excess playedo greater role against fungal attack. Interestingly, (−)-mesquitolroved to be more active than the whole sum of total flavanols.

In contrast, these data did not fit in the case of the heartwoodf P. kuntzei for either phenolic compounds or (−)-mesquitol. Thisircumstance suggests that these substances are not unique factorsor determination of the durability of the species considered.

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

cknowledgements

We gratefully acknowledge Prof. Philippe Gérardin of LERMAB,ancy 1 University, France, for having provided (−)-mesquitol.he authors would like to thank Mr. Kévin Ader (GENOBOIS,

PRESSProducts xxx (2011) xxx–xxx

INRA Orleans, France) for his technical assistance for HPLCanalysis.

This study was done within the frame of the European Unionproject Alfa II-0266-FA (GEMA: Genètica de la Madera). C. Pomettireceived a fellowship from the European Union to carry out thisstudy.

References

Abicalcados (Associacão Brasileira das Indústrias de Calcados), 2009. ResenhaEstatística. UIC – Unidade de Inteligência Comercial, Novo Hamburgo.

Amborabé, B.E., Fleurat-Lessard, P., Chollet, J.F., Roblin, G., 2002. Antifungal effectsof salicylic acid and other benzoic acid derivatives towards Eutypa lata:structure–activity relationship. Plant Physiol. Biochem. 40, 1051–1060.

Boizot, N., Charpentier, J.P., 2006. Méthode rapide d’évaluation du contenu encomposés phénoliques des organes d’un arbre forestier. Le Cahier des Tech-niques de l’INRA, Numéro spécial 2006: Méthodes et outils pour l’observationet l’évaluation des milieux forestiers, prairiaux et aquatiques, pp. 79–82.

Burkart, A., 1976. A monograph of the genus Prosopis. J. Arnold Arboretum 57,219–530.

Carrillo, A., Mayer, I., Koch, G., Hapla, F., 2008. Wood anatomical characteristics andchemical composition of Prosopis laevigata grown in the Northwest of Mexico.IAWA J. 29 (1), 25–34.

Cialdella, A.M., 1984. El género Acacia (Leguminosae) en la Argentina. Darwiniana25, 59–111.

Cialdella, A.M., 1997. Acacia. In: Hunziker, A.T. (Ed.), Flora fanerogámica Argentina,fascicle 25. Proflora CONICET, Córdoba, Argentina, pp. 3–21.

D’Antoni, H.L., Solbrig, O.T., 1977. Algarrobos in South American cultures past andpresent. In: Simpson, B.B. (Ed.), Mesquite its Biology in Two Desert Ecosystems.Hutchinson, Ross Publ., Stroudsburg, Dowden, pp. 189–199.

FAO, 1988. The current state of knowledge on Prosopis juliflora. In: Habit, M.A., Saave-dra, J.C. (Eds.), Food and Agriculture Organization of the United Nations. PlantProduction and Protection Division, Rome.

Fengel, D., Wegener, G., 1984. Wood. Chemistry, Ultrastructure Reactions. DeGruyter, Berlin.

Gérardin, P., Neya, B., Dumarcay, S., Petrissans, M., Serraj, M., Huber, F., 2004.Contribution of gums to natural durability of Prosopis africana heartwood. Holz-forschung 58, 39–44.

Gierlinger, N., Jacques, D., Schwanninger, M., Wimmer, R., Pâques, L.E., 2004. Heart-wood extractives and lignin content of different larch species (Larix sp.) andrelationships to brown-rot decay-resistance. Trees 18, 230–236.

Goldstein, I.S., Villareal, A., 1972. Chemical composition and accessibility to celluloseof mesquite wood. Wood Sci. 5 (1), 15–20.

Harju, A.M., Venäläinen, M., 2006. Measuring the decay resistance of Scots pineheartwood indirectly by the Folin-Ciocalteu assay. Can. J. For. Res. 36 (7),1797–1804.

Hernández, R.E., 2007. Swelling properties of hardwoods as affected by their extra-neous substances, wood density, and interlocked grain. Wood Fiber Sci. 39 (1),146–158.

Hillis, W.E., 1962. The distribution and formation of polyphenols within the tree. In:Hillis, W.E. (Ed.), Wood Extractives and Their Significance to the Pulp and PaperIndustries. Academic Press, New York, pp. 59–131.

Hillis, W.E., 1971. Distribution, properties and formation of some wood extractives.Wood Sci. Technol. 5, 272–289.

Hillis, W.E., 1987. Heartwood and tree exudates. Springer-Verlag, Berlin.IPPC: Integrated Pollution Prevention and Control Bureau, 2009. Reference Docu-

ment on Best Available Techniques (BREF) in the Tanning of Hides and Skins,Document formally adopted by the European Commission, Draft 27/02/2009.European Commission, Joint Research Centre, Institute for Prospective Techno-logical Studies, Seville.

ISO/DIS 14088, 2009. Leather. Chemical Tests. Quantitative Analysis of Tan-ning Agents by Filter Method. International Organization for Standardization,Geneva.

Karlin, O.U., Coirini, R.O., Catalan, L., Zapata, R., 1997. Acacia caven. In: OficinaRegional de la FAO para America Latina y el Caribe (Ed.), Especies arbóreas yarbustivas para las zonas áridas y semiáridas de América Latina. Zonas áridas ysemiáridas, 12. FAO/PNUMA, Santiago, Chile, pp. 157–167.

Luckow, M., 2005. Tribe Mimoseae. In: Lewis, G., Schrire, B., Mackinder, B., Lock, M.(Eds.), Legumes of the World. Royal Botanic Gardens, Kew, UK, pp. 163–183.

Magel, E., Jay-Allemand, C., Ziegler, H., 1994. Formation of heartwood substancesin the stemwood of Robinia pseudoacacia L.: II. Distribution of nonstructuralcarbohydrates and wood extractives across the trunk. Trees 8, 165–171.

Magel, E., 2000. Biochemistry and physiology of heartwood formation. In: Savige,R., Barnett, J., Napier, R. (Eds.), Molecular and Cell Biology of Wood Formation.BIOS Scientific Publishers, Oxford, pp. 363–376.

Paes, J.B., Morais, V.M., Lima, C.R., Santos, G.J.C., 2009. Resistência natural de novemadeiras do semiárido brasileiro a fungos xilófagos em simulares de campo.Rev. Árvore 33 (3), 511–520.

several types of extractives of five native argentine wood species of011.02.003

Pometti, C.L., Pizzo, B., Brunetti, M., Macchioni, N., Ewens, M., Saidman, B.O., 2009.Argentinean native woods species: physical and mechanical characterization ofsome Prosopis species and Acacia aroma (Leguminosae; Mimosoideae). Biore-source Technol. 100 (6), 1999–2004.

Pometti, C.L., Palanti, S., Pizzo, B., Charpentier, J.-P., Boizot, N., Resio, C., Saidman, B.O.,2010. Durability of five native Argentine wood species of the genera Prosopis

ING

I

s and

R

R

S

S

S

S

S

(Eucalyptus globulus) bark extracts. Ind. Crop Prod. 29, 364–370.

ARTICLEModel

NDCRO-5631; No. of Pages 9

B. Pizzo et al. / Industrial Crop

and Acacia decayed by rot fungi and its relationship with extractive content.Biodegradation 21 (5), 753–760.

eadel, K., Seigler, D., Hwang, K., Keesy, J., Seilheimer, S., 2001. Tannins fromMimosoid Legumes of Texas and Mexico. Econ. Bot. 55 (2), 212–222.

ice, E.L., 1983. Allelopathy. Physiological Ecology, second ed. Academic Press, Lon-don.

cholz, G., Windeisen, E., Liebner, F., Bäucker, E., Bues, C.-T., 2010. Wood Anatomi-cal features and chemical composition of Prosopis kuntzei from the Paraguayanchaco. IAWA J. 31 (1), 39–52.

chultz, T.P., Nicholas, D.D., 1997. Susceptibility of Angiosperm Sapwood toWhite-Rot Fungal Colonization and Subsequent Degradation: A Hypothesis.International Research Group on Wood Protection, Doc. No.: IRG/WP 97-10211,10 pp.

hah, J.J., Baqui, S., Pandalai, R.C., Patel, K.R., 1981. Histochemical changes in Acacianilotica L. during transition from sapwood to heartwood. IAWA Bull. 2 (1), 31–36.

Please cite this article in press as: Pizzo, B., et al., Relationships involvinggenera Prosopis and Acacia. Ind. Crops Prod. (2011), doi:10.1016/j.indcrop.2

irmah, P., Muisu, F., Mburu, F., Dumarcay, S., Gérardin, P., 2008. Evaluation ofProsopis juliflora properties as an alternative to wood shortage in Kenya. BoisForets Tropiques 298 (4), 27–37.

irmah, P., Iaych, K., Poaty, B., Dumarcay, S., Gérardin, P., 2009a. Effect of Extractiveson Durability of Prosopis juliflora Heartwood. International Research Group onWood Protection, Doc. No.: IRG/WP 09-30518, 18 pp.

PRESSProducts xxx (2011) xxx–xxx 9

Sirmah, P., Dumarcay, S., Masson, E., Gérardin, P., 2009b. Unusual amount of (−)-mesquitol from the heartwood of Prosopis juliflora. Nat. Prod. Res. 23 (2),183–189.

TAPPI Test Method T204 cm-96, 1996. Solvent Extractives of Wood and Pulp.Taylor, A.M., Gartner, B.L., Morrell, J.J., 2002. Heartwood formation and natural dura-

bility. A review. Wood Fiber Sci. 34 (4), 587–611.Taylor, A.M., Baek, S.H., Jeong, M.K., Nix, G., 2008. Wood shrinkage prediction using

NIR spectroscopy. Wood Fiber Sci. 40 (2), 301–307.Tortorelli, L.A., 1956. Maderas y bosques Argentinos. Editorial ACME, S.A.C.I., Buenos

Aires.Treutter, D., 1989. Chemical reaction detection of catechins and proanthocyanidins

with 4-dimethylaminocinnamaldehyde. J. Chromatogr. 467, 185–193.Vázquez, G., González-Alvarez, J., Santos, J., Freire, M.S., Antorrena, G., 2009. Evalua-

tion of potential applications for chestnut (Castanea sativa) shell and eucalyptus

several types of extractives of five native argentine wood species of011.02.003

Wiley, A.T., 1977. Moisture Relations of Mesquite Wood Publication n. 113. TexasForest Service, College Station, Texas.

Zabielska-Matejuk, J., 2005. Antifungal properties of new quaternary ammo-nium compounds in relation to their surface activity. Wood Sci. Technol. 39,235–243.