Pine Extracts Research Articles

Benchmarking of Individual Tree Segmentation Methods in Mediterranean Forest Based on Point Clouds from Unmanned Aerial Vehicle Imagery and Low-Density Airborne Laser Scanning

Three raster-based (RB) and one point cloud-based (PCB) algorithms were tested to segment individual Aleppo pine trees and extract their tree height (H) and crown diameter (CD) using two types of point clouds generated from two different techniques: (1) Low-Density (≈1.5 points/m2) Airborne Laser Scanning (LD-ALS) and (2) photogrammetry based on high-resolution unmanned aerial vehicle (UAV) images. Through intensive experiments, it was concluded that the tested RB algorithms performed best in the case of UAV point clouds (F1-score > 80.57%, H Pearson’s r > 0.97, and CD Pearson´s r > 0.73), while the PCB algorithm yielded the best results when working with LD-ALS point clouds (F1-score = 89.51%, H Pearson´s r = 0.94, and CD Pearson´s r = 0.57). The best set of algorithm parameters was applied to all plots, i.e., it was not optimized for each plot, in order to develop an automatic pipeline for mapping large areas of Mediterranean forests. In this case, tree detection and height estimation showed good results for both UAV and LD-ALS (F1-score > 85% and >76%, and H Pearson´s r > 0.96 and >0.93, respectively). However, very poor results were found when estimating crown diameter (CD Pearson´s r around 0.20 for both approaches).

A Sustainable Innovation: Functionalization of Pasta with Methanol Extract of Turkish Red Pine (Pinus brutia Ten.) Barks

A Sustainable Innovation: Functionalization of Pasta with Methanol Extract of Turkish Red Pine (Pinus brutia Ten.) Barks

Neuronal cell protective effects of phenolic compounds derived from steam exploded nematode-infected pine

Pine wilt disease is one of the most serious forest diseases that kills pine trees. Most of the nematode-infected pines are fumigated or locally incinerated and are thus not appropriately utilized. This study explored methods to utilize abandoned nematode-infected pines. The chemical compositions of healthy and nematode-infected pines were analyzed, and the neuroprotective effects of phenolic compounds extracted after steam explosion treatment were investigated. In terms of chemical composition, the nematode-infected pine chips suffered more damage from the steam explosion treatment than the healthy pine chips. In addition, the total phenolic compound content showed a clear difference depending on the presence of infection and steam explosion conditions. The maximum total phenolic compound content of extracted ethanol was found when the nematode-infected pine chip was subjected to steam explosion with a severity factor (Ro) of 3.82. The steam exploded pine extract of 10 μg/mL inhibited glutamate-induced early apoptotic cell death compared to cells treated with 10 mM glutamate alone. These results suggested that steam-exploded pine can be used as an effective natural material for neuronal cell protection.

Anti-photoaging effects of steam-exploded pine (Pinus densiflora) extract in ultraviolet B irradiation-damaged HaCaT keratinocytes

Ultraviolet B (UVB) irradiation causes photoaging, such as wrinkles, roughness and dryness of the skin, and it activates the production of reactive oxygen species (ROS) and inflammatory cytokines. In this study, the anti-photoaging activity of SEP-E (steam-exploded pine extract) was evaluated in HaCaT keratinocytes damaged by UVB irradiation. SEP-E treatment showed cytoprotective effects in HaCaT keratinocytes irradiated with UVB (40 mJ/cm2). SEP-E treatment reduced ROS overproduction and promoted the expression of antioxidant enzymes, such as catalase, superoxide dismutase 1, and superoxide dismutase 2. Additionally, SEP-E treatment suppressed the expression of inflammatory cytokines, including interleukin 6, interleukin 8, and monocyte chemoattractant protein-1. Consequently, SEP-E shows potential as a natural material for photoaging treatment.

Surface assisted laser desorption/ionization mass spectrometry of lithium cationized lignans – A tool for rapid screening of plant extracts

Lignans are one of the most widespread classes of plant secondary metabolites possessing unique biological activities. The search for new sources of such compounds, their screening and identification in plant biomass is an urgent task, requiring the use of advanced analytical methods. In the present study, matrix-free surface assisted laser desorption/ionization (SALDI) mass spectrometry was proposed for its solution. The combination of carbon nanocoating sputtered on a target plate with lithium cationization allowed obtaining high-quality mass spectra of eight coniferous wood lignans with different bonds between aromatic units (secoisolariciresinol, matairesinol, 7-hydroxymatairesinol, nortrachelogenin, pinoresinol, guaiacylglycerol-β-guaiacyl ether, dehydrodihydrodiisoeugenol, and divanillin). Three types of fragmentation methods (post-source decay, high- and low-energy collision induced dissociation) for the first time were implemented on two types of MALDI instruments. Regardless of tandem mass spectrometry technique, lignans demonstrated the similar fragmentation patterns including the cleavage of bonds between aromatic units with the formation of mostly lithiated product ions. The low-energy collision induced dissociation in quadrupole ion trap provided the most informative tandem mass spectra and multi-stage fragmentation capabilities in structural studies. On this basis, an approach to rapid, high-throughput, and low-cost screening and tentative identification of lignans including isomeric compounds in plant biomass was developed and successfully tested on real samples of pine, fir, spruce, and larch knotwood extracts.

Review of the pharmacokinetics of French maritime pine bark extract (Pycnogenol®) in humans.

The French maritime pine bark extract Pycnogenol® is a proprietary product from Pinus pinaster Aiton. It complies with the quality specifications in the United States Pharmacopeia monograph "Pine extract" in the section of dietary supplements. Pycnogenol® is standardized to contain 65-75% procyanidins which are a variety of biopolymers consisting of catechin and epicatechin monomeric units. The effects of Pycnogenol® have been researched in a multitude of human studies. The basis for any in vivo activity is the bioavailability of constituents and metabolites of the extract. General principles of compound absorption, distribution, metabolism and elimination as well as specific data from studies with Pycnogenol® are summarized and discussed in this review. Based on plasma concentration profiles it can be concluded that low molecular weight constituents of the extract, such as catechin, caffeic and ferulic acid, taxifolin are readily absorbed from the small intestine into systemic circulation. Procyanidin oligomers and polymers are subjected to gut microbial degradation in the large intestine yielding small bioavailable metabolites such as 5-(3',4'-dihydroxyphenyl)-γ-valerolactone. After intake of Pycnogenol®, constituents and metabolites have been also detected in blood cells, synovial fluid and saliva indicating a substantial distribution in compartments other than serum. In studies simultaneously investigating concentrations in different specimen, a preferential distribution of individual compounds has been observed, e.g., of ferulic acid and 5-(3',4'-dihydroxyphenyl)-γ-valerolactone into synovial fluid compared to serum. The main route of elimination of constituents and metabolites of the French pine bark extract is the renal excretion. The broad knowledge accumulated regarding the pharmacokinetics of compounds and metabolites of Pycnogenol® constitute a rational basis for effects characterized on a cellular level and observed in human clinical studies.

Retention and concentration of Reticulitermes speratus feeding-deterrent from fungus-decayed Japanese red pine extract

Retention and concentration of <i>Reticulitermes speratus</i> feeding-deterrent from fungus-decayed Japanese red pine extract

Application of Aleppo pine extract for skin burn treatment.

To investigate the Pinus halepensis extracts and determine its healing and antibacterial effects, and to evaluate the treatment of skin burns. Aqueous and ethanolic extracts and topical based on Aleppo pine plant extracts were prepared. Thirty male and female Wistar rats were used to study the cutaneous toxicity of extracts from the bark of P. halepensis. The extracts' healing potential for burn wounds were also assessed by evaluating the clinical and macroscopic aspects of the wounds. The antibacterial activity of crude extracts of P. halepensis as well as its wound healing abilities was verified in this investigation. In animals with acute dermal toxicity, there were no signs of treatment-related toxicity or death. The extracts of these plants could be transformed into phytomedicines for the treatment of infected wounds. The results demonstrated that formulated ointments are successful in treating second-degree burns in rats and may be suitable for the short-term therapeutic treatment of second-degree burns. This study successfully answered our problem, regarding the efficacy of our extract for treating second-degree burns in rats. Further studies are needed to confirm these results by identifying the molecules responsible for these activities and examining their mechanism of action.

Влияние кормовой добавки из минерального сырья и хвойных экстрактов на интенсивность роста телят

Исследования проводили в 2023 году в ОПХ «Михайловское» (филиале ФИЦ КНЦ СО РАН) в Ужурском районе Красноярского края, на тёлочках чёрно-пёстрой породы двухмесячного возраста, в течение 90 дней. Целью исследований было изучение влияние разных способов скармливания кормовых добавок из природного растительного и минерального сырья на показатели роста телят. Кормовые добавки из местного растительного и минерального сырья применяются для оптимизации рационов молодняка крупного рогатого скота и способствуют укреплению здоровья, повышению резистентности, увеличению привесов. Поскольку кормовые добавки из лесных ресурсов содержат трудноперевариваемые компоненты, способ скармливания оказывает влияние на их усвояемость и эффективность. По принципу аналогов были сформированы две опытных и контрольная группы телят по 14 голов в каждой. Все телята получали основной рацион, опытные группы в дополнение к основному рациону получали кормовые добавки: в 1-й группе в сухом виде (г на голову в сутки): муку из сосновой хвои — 20, муку из скорлупы кедрового ореха — 20, арабиногалактан — 2,5, вспученный вермикулит — 20; во 2-й группе: вспученный вермикулит, обогащённый водным экстрактом сосновой хвои, скорлупы кедрового ореха и арабиногалактана, — 20 г на голову в сутки. В результате исследований было определено, что телята 2-й опытной группы имели наиболее высокие показатели роста, что выразилось в увеличении по сравнению с контрольной группой абсолютного прироста живой массы телят на 5,47%, относительного — на 1,03%, среднесуточного — на 5,34%. Телята 2-й опытной группы превосходили телят контрольной по величине индексов телосложения: массивности — на 3,19%, компактности — на 1,22%, формата — на 1,77%, костистости — на 0,13%. Отрицательного влияния на рост и развитие телят кормовые добавки не оказали, сохранность телят составила 100%. The investigation took place at the OPKH “Mikhaylovskoe” (branch of the Federal Research Center “Krasnoyarsk Research Center of the Siberian Branch of the Russian Academy of Sciences”) in the Krasnoyarsk region in 2023. Two-month-old black-and-white heifers were tested for 90 days. The aim was to analyze the impact of a number of feed additives from plant and mineral components on the growth of heifers. Such additives were used to optimize the diet of young cattle and affect positively their health, immune system and weight gain. Since the feed additives from forest materials contained poorly digestible components, the method of feeding affected their digestibility and effectiveness. Two test and one control analogue groups were formed of 14 heads each. All the animals obtained a basic diet but the test groups additionally consumed the feed additives. The first group was fed (g/head daily) by pine needle flour — 20, pine nut shell flour — 20, arabinogalactan — 2.5, expanded vermiculite — 20; the second one — expanded vermiculite enriched with the water extract of pine needles, pine nut shells and arabinogalactan — 20 g/head daily. The second test group showed the better increase in the absolute live weight by 5.47%, the relative one — by 1.03%, the average daily weight gain — by 5.34%. The second test group exceeded the control in muscle mass by 3.19%, blockiness — by 1.22%, body size — by 1.77%, bone weight — by 0.13%. The additives showed no negative effect on the health of heifers.

Suppression of dengue virus replication by the French maritime pine extract Pycnogenol®

Dengue virus (DENV) is mainly found in the tropics and infects approximately 400 million people annually. However, no clinically available therapeutic agents specific to dengue have been developed. Here, we examined the potential antiviral effects of the French maritime pine extract Pycnogenol® (PYC) against DENV because we previously found that the extract exerts antiviral effects on hepatitis C virus, which belongs to the Flavivirus family. First, we examined the efficacy of PYC against DENV1, 2, 3, and 4 serotypes and determined that it had a dose-dependent suppressive effect on the viral load, especially in the supernatant. This inhibitory effect of PYC may target the late stages of infection such as maturation and secretion, but not replication. Next, we examined the efficacy of PYC against DENV infection in type I interferon (IFN) receptor knockout mice (A129). As the propagation of DENV2 was the highest among the four serotypes, we used this serotype in our murine model experiments. We found that PYC significantly inhibited DENV2 replication in mice on day 4 without significantly decreasing body weight or survival ratio. We further examined the mechanism of action of PYC in DENV2 infection by characterizing the main PYC targets among the host (viral) factors and silencing them using siRNA. Silencing long noncoding-interferon-induced protein (lnc-IFI)-44, polycystic kidney disease 1-like 3 (Pkd1l3), and ubiquitin-specific peptidase 31 (Usp31) inhibited the replication of DENV2. Thus, the results of this study shed light on the inhibitory effects of PYC on DENV replication and its underlying mechanisms.

SEARCH FOR THE THERAPEUTIC POTENTIAL OF BIOLOGICALLY ACTIVE SUBSTANCES CONTAINED IN CONIFEROUS PLANTS

The paper presents scientific information about the problems in the search for therapeutic potential in coniferous plants widely used in folk medicine. Samples of coniferous plants growing in the mountain forests of the Western Altai in the eastern part of Kazakhstan were selected for the experiment: Baltic pine (Pinus sylvestris L.), European spruce (Picea abies L.), Siberian fir (Abies sibírica), Siberian pine (Pinus sibirica DuTour), and common juniper (Juniperus communis L.). During the study, the phytochemical composition of the components of P. sylvestris L. essential oils was determined by the indicators of sesquiterpenic fraction (69.76%), terpenoids (20.0%), and monoterpenes (5.51%). Using modern methods of studying biological activity (antimicrobial, antifungal, and anthelmintic), the authors established the presence of biological activity in the extracts of selected coniferous plants. In all coniferous plants, bactericidal activity was manifested in water decoctions, where biological preparations of Siberian fir and Baltic pine were more active. The oil extracts showed less bactericidal activity. Among them, extracts of Siberian pine and juniper were inactive, and the extract of European spruce was more active in its native form and 1:2 dilution. Among plants with a complete absence of bactericidal activity against the Candida parapsilosis opportunistic yeast, Siberian fir should be named. In other coniferous plants (European spruce, Baltic pine, juniper), bactericidal activity was detected only in oil solutions in a dilution of 1:2, and oil extract of Siberian pine in a dilution of 1:8 had a suppressive effect. Water/alcohol tincture of Siberian fir was found to have high fungicidal activity against Aspergillusniger, which continued to influence the growth of the micromycete at a dilution of 1:64 during the observation period. The presence of antiparasitic properties was observed in some plant extracts of coniferous forest plants. The best results were noted in alcohol tinctures of Baltic pine, juniper, and Siberian pine.

Screening of Effective Leaf Extracts for Weed Management in Little Millet (Panicum sumatrense Roth ex Roem. &amp; Schult)

Field experiment was conducted at Tamil Nadu Agricultural University, Coimbatore in January 2022 by seven different leaf extracts as an allelopathical compound in order to choose the best alternative to chemical herbicides by non-chemical weed management approach in little millet owing to the great surge of organic farming in millet production nowadays. Screening trail has been conducted to observe the effect of leaf extracts (Tamarind,Casuarina,Castor,Papaya, Teak,Pine,Nerium) with 20 &amp; 30% concentration on weed control. This experiment laid out in a randomized block design and was replicated twice with 15 different treatments. The findings of this investigation demonstrated that the pre emergence (3 DAS) application of Tamarind leaf extract (30%), Casuarina leaf extract (30%). Castor leaf extract (30%). Papaya leaf extract (30%). Teak leaf extract (30%). Pine leaf extract (30%) and Nerium leaf extract (30%) pronounced the lowest weed density and highest weed control efficiency among fifteen treatments. Based on the results of the experiment, it was concluded that pre emergence application of any different leaf extract among the fifteen treatments, Tamarind, Casuarina, Castor, Papaya, Teak, Pine, and Nerium leaf extracts with 30% concentration had found the allelopathic potential to reduce the weed density and recorded high weed control efficiency with no phytotoxicity on the little millet.

Antioxidant and Antibacterial Activities of Methanol Extracts from Various Plant Parts of Pomegranate and Anatolian Black Pine

Oxidative stress and bacterial infections threaten human and animal health. Different parts of the plants have a great potential to be used as a source of antioxidant and antibacterial agents for human or animal welfare, because of their active metabolites. This study was conducted to assess the antioxidant and antibacterial activities of methanolic extracts from the leaves, flowers, whole fruits, and woods of pomegranate (Punica granatum L.), and the leaves, cones, and woods of Anatolian black pine [Pinus nigra Arn. subsp. pallasiana (Lamb.) Holmboe]. Antioxidant activity was screened by DPPH and CUPRAC assays. Antimicrobial activity was examined by disc diffusion test against fish pathogens, Aeromonas hydrophila, Vibrio anguillarum, Yersinia ruckeri and Lactococcus garvieae.&#x0D; Pomegranate whole fruit extract possessed superior antioxidant activity even higher than ascorbic acid. All parts of pomegranate, except wood, also exhibited significant antibacterial activity against fish pathogens. Black pine cone extract slightly inhibited the growth of fish pathogens while other pine extracts were inactive. This study reveals that the whole fruit of pomegranate is a prominent source of antioxidant and antibacterial metabolites. Cones of Anatolian black pine also seem to be a source of antibacterial compounds against fish pathogens.

Characterization of host factors associated with the internal ribosomal entry sites of foot-and-mouth disease and classical swine fever viruses

Foot-and-mouth disease virus (FMDV) and classical swine fever virus (CSFV) possess positive-sense single-stranded RNA genomes and an internal ribosomal entry site (IRES) element within their 5′-untranslated regions. To investigate the common host factors associated with these IRESs, we established cell lines expressing a bicistronic luciferase reporter plasmid containing an FMDV-IRES or CSFV-IRES element between the Renilla and firefly luciferase genes. First, we treated FMDV-IRES cells with the French maritime pine extract, Pycnogenol (PYC), and examined its suppressive effect on FMDV-IRES activity, as PYC has been reported to have antiviral properties. Next, we performed microarray analysis to identify the host factors that modified their expression upon treatment with PYC, and confirmed their function using specific siRNAs. We found that polycystic kidney disease 1-like 3 (PKD1L3) and ubiquitin-specific peptidase 31 (USP31) were associated with FMDV-IRES activity. Moreover, silencing of these factors significantly suppressed CSFV-IRES activity. Thus, PKD1L3 and USP31 are host factors associated with the functions of FMDV- and CSFV-IRES elements.

Green synthesis of cerium oxide nanoparticles from turmeric and kinds of honey: characterisations, antioxidant and photocatalytic dye degradation activities

The environmentally compatible and cost-effective green synthesis of cerium oxide nanoparticles (CeO2-NPs) was performed starting from bioactive natural materials, i.e., blossom, pine, chestnut honey, and turmeric extracts. The sizes, surface charges, morphologies, band gap energies, antioxidant, and photocatalytic activities of the synthesised nanoparticles were examined comparatively. The x-ray diffraction (XRD) studies confirmed the crystallinity and purity of CeO2-NPs. Transmission electron microscope (TEM) images indicated that the CeO2-NPs synthesised have spherical shapes. Particle sizes of honey originated NPs changed as 1.23, 2.61, 3.02 nm for the blossom, chestnut, and pine honey, respectively. NPs obtained from turmeric extract had 6.08 nm particle size. The isoelectric points of CeO2-NPs were about 4 when the starting material was blossom and pine honey. For the chestnut honey and turmeric as starting material, the isoelectric points of NPs were about 6 and 9.5, respectively. The band gap energies changed between 2.80-3.21 eV. All green synthesised nanoparticles exhibited high antioxidant activities according to the DPPH method, changing between 32.4 and 64.5 μg ml−1 as IC50 values. Activity values increased in the order of blossom, pine, chestnut honey, and turmeric. All synthesised NPs reflected the literature antioxidant rankings of the starting natural materials. Thanks to the strong redox property of the CeO2-NPs, high degradation efficiencies (between 83.9 and 93.4%) were obtained for MB under UV light irradiation. The natural starting materials used created differences in the physical and activity properties of the NPs. Green synthesis of CeO2-NPs with new natural materials will expand their usage areas.

Growth Inhibition and Apoptotic Effect of Pine Extract and Abietic Acid on MCF-7 Breast Cancer Cells via Alteration of Multiple Gene Expressions Using In Vitro Approach.

In vitro anti-proliferative activity of Pinus palustris extract and its purified abietic acid was assessed against different human cancer cell lines (HepG-2, MCF-7 and HCT-116) compared to normal WI-38 cell line. Abietic acid showed more promising IC50 values against MCF-7 cells than pine extract (0.06 µg/mL and 0.11 µM, respectively), with insignificant cytotoxicity toward normal fibroblast WI-38 cells. Abietic acid triggered both G2/M cell arrest and subG0-G1 subpopulation in MCF-7, compared to SubG0-G1 subpopulation arrest only for the extract. It also induced overexpression of key apoptotic genes (Fas, FasL, Casp3, Casp8, Cyt-C and Bax) and downregulation of both proliferation (VEGF, IGFR1, TGF-β) and oncogenic (C-myc and NF-κB) genes. Additionally, abietic acid induced overexpression of cytochrome-C protein. Furthermore, it increased levels of total antioxidants to diminish carcinogenesis and chemotherapy resistance. P. palustris is a valuable source of active abietic acid, an antiproliferative agent to MCF-7 cells through induction of apoptosis with promising future anticancer agency in breast cancer therapy.

“Green technology” processing of pine (Pinus sylvestris L.) and larch (Larix sibirica Ledeb.) wood greenery to produce bioactive extracts

Abstract In order to explore the extractives of conifers an effective and environmentally friendly method of extraction with aqueous-alkaline solution allowing to isolate up to 10.4% of extractive substances (ES) from pine wood greenery and up to 6.9% from larch wood greenery was investigated. The component fractional composition of aqueous-alkaline extracts was studied. The antioxidant fraction activity of neutral and acidic components isolated from the produced extracts was evaluated. It was found that these fractions have a high antioxidant activity, where the activity of larch extract components was higher than that of the respective components of pine extract. Due to their rich chemical composition and high biological activity, extracts of pine and larch wood greenery produced by aqueous-alkaline extraction have good application prospects as biologically active preparations.

Comparison of ratios combination calcium hydroxide Ca(OH)2 with red pine (Pinus densiflora) of viscosity

Background: Calcium hydroxide is a gold standard for root canal sealing material. However, there are many defects in calcium hydroxide that have prompted many researchers to look for alternative materials, including natural origin ingredients. Red pine (Pinus densiflora) is often used in dentistry for its antioxidant and antibacterial properties. The mixture of calcium hydroxide and red pine has never been achieved before. One of the criteria for material sealing is that the channel should be fully sealed with high flow ability and low viscosity. Therefore, this research is performed to analyze the viscosity value of the mixture of calcium hydroxide and red pine (Pinus densiflora). Purpose: Knowing the difference in viscosity of the combination of calcium hydroxide and red pine with a ratio of 1:1, 1:1.5, and 1:2. Methods: This study used four treatment groups, with each group consisting of 8 replications. Group 1 was a combination of calcium hydroxide and red pine with a 1: 1, group 2 the ratio was 1: 1.5, group 3 had the ratio 1: 2, and the positive control group used calcium hydroxide and a sterile aquadest. Calcium hydroxide in powder form and an extract of red pine in liquid form are mixed according to the ratio. The viscosity value is measured using a viscosity tester, namely the Brookfield Viscometer. Results: The control group had a lower viscosity than group 3, group 3, and group 2 than group 1. Conclusion: Combination of calcium hydroxide and red pine with a ratio of 1:2, the lowest viscosity was obtained compared to the ratio of 1: 1 and 1: 1.5

Characteristics of the Polyphenolic Profile and Antioxidant Activity of Cone Extracts from Conifers Determined Using Electrochemical and Spectrophotometric Methods.

The aim of the study was to analyze the polyphenolic profile of cone extracts of Douglas fir, Scots pine and Korean fir, and to study their antioxidant activity. The mechanism of electro-oxidation of polyphenols (such as procyanidins and catechins) from cone extracts was investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV), as well as spectrophotometric methods—ABTS (2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonate)), DPPH (2,2-diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power ) and CUPRAC (CUPric Reducing Antioxidant Capacity). The scientific novelty of the research is the comprehensive analysis of cone extracts in terms of antioxidant properties. Due to the high polyphenol content, the extracts showed significant ability to reduce oxidative reactions, as well as the ability to scavenge free radicals and transition metal ions. Douglas fir, Scots pine and Korean fir cone extracts can potentially be used as natural stabilizers, preservatives and antimicrobial substances in the food industry and in medications.

Effect of Using Urea Formaldehyde Modified with Extracts in Plywood on Formaldehyde Emission

Formaldehyde-based adhesives are used in the forestry industry. This is because formaldehyde is inexpensive, easy to use and resistant to moisture; it also has particular mechanical effects. Formaldehyde has both advantages and disadvantages. It is known that various diseases such as lung cancer occur in humans as a result of the release of formaldehyde into the air during and after board production. In this study, a urea formaldehyde glue mixture was prepared by using four different fillers (extract of maritime pine (Pinus pinaster) and elm (Ulmus glabra) bark, extract of hazelnut (Corylus avellana) husk and acorn tannins) at two different ratios. The bonding shear strength of pine (Pinus sylvestris) and spruce (Picea orientalis) plywood produced with urea formaldehyde adhesive was tested according to EN 314-1 standard. All plywood, except the plywood with acorn tannin, met the requirements of the standard. A formaldehyde emission test of the plywood was carried out in accordance with EN 713-3 standard. With this approach, it is possible to quickly determine formaldehyde emissions. Experimental results were obtained for subsequent measurements, including chamber tests. It was observed that the elm bark extract reduced the formaldehyde emission of pine plywood by 40 %, while other fillers reduced it by 3-37 %.