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1.
Soluble extractives in wood function to protect living trees from destructive agents and also contribute to wood color and fragrance. Some extractive components have biological activities with medical applications. They also play important roles in wood processing and related applications. To increase the knowledge of wood chemistry, maple and oak were extracted by water. Ultraviolet/visible (UV/vis) spectroscopy indicated the presence of a phenolic compound, resorcinol, in maple extractives having higher molecular mass and more aromatic components than oak extractives. Negative and positive electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT‐ICR‐MS) identified thousands of formulas in the two samples in the m/z range of 200 to 800. They mainly fall into the lignin‐like, carbohydrate‐like, and tannin‐like compound categories. The top 25 peaks (ie, formulas) with the highest relative magnitude in negative ESI represented nearly 50% of the summed total spectral magnitude of all formulas assigned in the maple and oak extractives. Furthermore, the base peak (ie, most abundant peak) accounted for about 14% of the total abundance in each wood sample. Literature comparisons identified 17 of 20 formulas in the top five peaks of the four spectra as specific bioactive compounds in trees and other plants, implying the potential to explore utilization of maple and oak extractives for functional and medicinal applications. The various profiling of the top 25 peaks from the two samples also suggested the possible application of FT‐ICR‐MS for detecting chemical markers useful in profiling and identification of wood types and sources.  相似文献   

2.
Eighteen physical and chemical variables were determined in 25 samples of commercial tomato products: total solids, soluble solids, water activity, lycopene, 5-hydroxymethyl-2-furfural, CIE(L*a*b*) components (L*, a*, b*, a*/b*, C*, H degrees), total acidity, sodium chloride, wet-weight pulp percentage, alcohol insoluble solids, total pectic substances, ascorbic acid, and pH. In order to maximize the variability of products, samples included crushed tomato, tomato puree, tomato paste, and heavy concentrates and were taken from Italy, France, Spain, Portugal, the United States, Mexico, Colombia, and Chile. Correlation analysis and multidimensional data analysis techniques (principal component analysis and hierarchical classifications) were used to describe the products' variability and to study the relationships among variables. Three variables were selected, with the aim of classifying the collection of samples in a way consistent with the classification obtained with the first principal components. These variables were soluble solids content, the CIE(L*a*b*) lightness parameter L*, and total pectic substances content.  相似文献   

3.
The chemical composition of extractives in the sapwood (SW), heartwood (HW), knotwood (KW), and branchwood (BW of silver fir (Abies alba Mill.) was analyzed, and their antifungal and antioxidant properties were studied. In addition, the variability of extractives content in a centripetal direction, i.e., from the periphery of the stem towards the pith, was investigated. The extracts were analyzed chemically with gravimetry, spectrophotometry, and chromatography. The antifungal and antioxidative properties of the extracts were evaluated by the agar well diffusion method and the diphenyl picrylhydrazyl radical scavenging method. Average amounts of hydrophilic extractives were higher in KW (up to 210.4 mg/g) and BW (148.6 mg/g) than in HW (34.1 mg/g) and SW (14.8 mg/g). Extractives identified included lignans (isolariciresinol, lariciresinol, secoisolariciresinol, pinoresinol, matairesinol) phenolic acids (homovanillic acid, coumaric acid, ferulic acid), and flavonoids epicatechin, taxifolin, quercetin). Secoisolariciresinol was confirmed to be the predominant compound in the KW (29.8 mg/g) and BW (37.6 mg/g) extracts. The largest amount of phenolic compounds was extracted from parts of knots (281.7 mg/g) embedded in the sapwood and from parts of branches (258.9 mg/g) adjacent to the stem. HW contained more lignans in its older sections. Hydrophilic extracts from knots and branches inhibited the growth of wood-decaying fungi and molds. KW and BW extracts were better free radical scavengers than HW extracts. The results of the biological activity tests suggest that the protective function of phenolic extracts in silver fir wood can also be explained by their antioxidative properties. The results of this study describe BW as a potential source of phenolic extractives in silver fir.  相似文献   

4.
Dalbergia sissoo is a woody plant with economic and medicinal value. As the pharmacological qualities and properties of the wood from this plant primarily depend on its extractives, in this study, the metabolomic analysis of extractives from its stems was carried out using UPLC-MS/MS. A total of 735 metabolites were detected from two groups of samples, heartwood and sapwood, with the largest number of terpenoids in type and the largest number of flavonoids in quantity. The PCA and cluster analysis showed significant differences in the metabolite composition between the two groups. The differential metabolites were mainly organic oxygen compounds, flavonoids, and isoflavones. Among the 105 differential metabolites, 26 metabolites were significantly higher in relative content in sapwood than in heartwood, while the other 79 metabolites were significantly higher in relative content in heartwood than in sapwood. KEGG metabolic pathway enrichment analysis showed that these differential metabolites were mainly enriched in three metabolic pathways: Flavonoid biosynthesis, isoflavonoid biosynthesis, and flavonoid and flavonol biosynthesis. This study provides a reference for metabolomics studies in Dalbergia and other woody plants.  相似文献   

5.
Six crystalline compounds, α-cedrol, β-sitosterol, cryptojaponol sugiol and two new diterpene phenols were isolated from the hexane extractive of wood of Juniperus formosana Hayata. Two new phenolic derivatives of deoxocryptojaponoi were established as 7α-methoxydeoxocryptojaponol and 7β-hydroxydeoxocryptojaponol, respectively, by chemical and physical evidence.  相似文献   

6.
Six crystalline compounds, α-cedrol, β-sitosterol, cryptojaponol sugiol and two new diterpene phenols were isolated from the hexane extractive of wood of Juniperus formosana Hayata. Two new phenolic derivatives of deoxocryptojaponol were established as 7α-methoxydeoxocryptojaponol and 7β-hydroxydeoxocryptojaponol, respectively, by chemical and physical evidence.  相似文献   

7.
This study shows the photo-stabilizing effect of extractives on wood. XPS and FTIR techniques were used to analyze the variations in chemical characteristics on the surfaces of non-extracted and extracted Acacia confusa heartwood after lightfastness test. XPS survey analyses reveal that non-extracted heartwood exhibits a higher O/C ratio than the extracted wood. Furthermore, results from the detailed analysis of C1s indicated that the photo-oxidative derivatives increased in both extracted and non-extracted specimens after lightfastness test. On extracted wood, the derivatives are mainly derived from lignin, whereas extractives are the major component responsible for the generation of derivatives on non-extracted wood surface. After leaching test of UV-irradiated specimens, it was noted that the degradation products were readily removed by water. More water-soluble derivatives were leached out from the extracted wood, although higher lignin content was observed on the non-extracted wood surface. In conclusion, it is shown that photodegradation of A. confusa wood can be retarded by extractives oxidation.  相似文献   

8.
Vegetable processing pomace contains valuable substances such as natural colors that can be reused as functional ingredients. Due to a large amount of water, they are an unstable material. The aim of our research was to assess how the pretreatment method (thermal or nonthermal) affects the properties of powders obtained from beet juice and pomace after the freeze-drying process. The raw material was steamed or sonicated for 10 or 15 min, and then squeezed into juice and pomace. Both squeezed products were freeze-dried. The content of dry substance; L*, a*, and b* color parameters; and the content of betalain pigments were analyzed. Pretreatments increased the proportion of red and yellow in the juices. Steam and ultrasound caused a significant reduction in parameter b* in the dried pomace. A significant increase in betanin in lyophilizates was observed after pretreatment with ultrasound and steam for 15 min. As a result of all experiments, dried juices and pomaces can also be used as a colorant source. However, there is higher potential with pomaces due to their additional internal substances as well as better storage properties. After a few hours, juice was sticky and not ready to use.  相似文献   

9.
Cherries are rich in bioactive phenolic compounds and are often fermented into cherry wines. The degradation of anthocyanins during storage will cause color deterioration. The study aimed to utilize sinapic acid and grape tannins in cherry wine to maintain a high fraction in the colored forms of anthocyanins, in order to maximize the color intensity, the latter being associated with good product quality. The effects on the anthocyanin profile and on color parameters of copigments, utilizing spectral measurement combined with UPLC-MS quantitative analysis, have been evaluated in sweet cherry wines. The copigmentation effect of sinapic acid and grape tannin was accompanied by the bathochromic shift and the hyperchromic effect, which lead to an increase in color intensity (lower L*, higher a* and b*). During the aging process, sinapic and grape tannin increased the content of pyranoanthocyanins in cherry wine, especially the addition of sinapic acid makes the cherry wine generate 10-syringyl-pyranocyanidin-3-rutinoside. These results demonstrate that sinapic acid is suitable for adding before alcohol fermentation, while grape tannins can be added before aging.  相似文献   

10.
This study compares the thermal stability of different wood species, which is an important factor for the production of wood–polymer composites (WPCs), and investigates the effect of extraction on thermal properties. The chemical composition of four wood species – Quercus alba, Pinus radiata, Eucalyptus grandis and Acacia cyclops – has been determined, as the species is expected to affect the thermal stability of wood. Subsequently, the hot-water (HW) extractives, ethanol/cyclohexane (E/C) extractives and both extractives were eliminated from the wood via Soxhlet extraction and the thermal stability of the wood determined with thermogravimetric analysis (TGA) under identical conditions. The results suggest that a higher cellulose and lignin content leads to better thermal stability of wood in different temperature regimes. In all cases, the removal of extractives improved the thermal stability of the wood. The effect of combined extractions was more pronounced than of an individual extraction and E/C-extraction caused less improvement in the thermal stability of wood than HW extraction. The degradation of the investigated wood extractives occurred at low rates over a broad temperature range. Pure cellulose exhibited superior thermal stability compared to wood, but differences were observed between the investigated wood species.  相似文献   

11.
The main constituents and cyclohexane extractives of wood obtained from planted and native oriental spruce, P. orientalis, were comparatively investigated. The plantation stand in Belgrad Forest near the city Istanbul is about 1000 km west to the original provenance in northeast Turkey with somewhat different environmental factors. The distribution of the main components and the total extractive contents in the woods were affected insignificantly. Only few differences were notable in the amount of sugar monomers of the main polyoses, mannan and xylan, when the native and planted woods were subject to total hydrolyses. The yield of lipophilic extractives in native and planted woods was almost the same. The composition of lipophilic extractives of the woods, determined after proper derivatization by GC-MS, were also not different qualitatively, but some constituents exhibited quantitative changes. Although the planted wood contained significantly more resin acids, sterols, and alcohols, the natural samples had more unsaturated fatty acids. __________ Published in Kimiya Prirodnikh Soedinenii No. 5, pp. 405–408, September–October, 2005.  相似文献   

12.
Abstract

The composition and the relative variation of secondary metabolites of Paulownia tomentosa S. wood under thermal effect is a little explored area. Wood material was previously thermo-treated at 210?°C for 3?hours using a press vacuum technology. Extractives of untreated and thermo-treated wood material achieved with Soxhlet extraction techniques were obtained. Then the extracts were chromatographed by using thin layer chromatography. Component groups in extracts were determined by gas chromatography in combination with mass spectrometry. In terms of wood change the thermo-treatment of wood induces a darkening of wood color surface (ΔL* = 28.3), an increase of mass loss (3.5%) and an increase of the amount of extractives and lignin content as well as an increase of the chloroform soluble fraction. This work mainly describes the chemical exploration of the extract from paulownia wood, leading to the isolation and identification of episesamin.  相似文献   

13.
Py–GC–MS was used to examine the components of vapor from rapid pyrolysis of larch wood and its model components, i.e. example cellulose, xylan, and lignin, and their mixture in accordance with the proportion of the components in larch wood. In this study, a total of 97 compounds in 12 categories were identified in the pyrolysis vapor and were compared. It was found that the most abundant chemical species in these five types of pyrolysis vapor were different. Saccharides and ketones were the major compounds in the pyrolysis vapor from microcrystalline cellulose and xylan, respectively, whereas the most abundant compounds in the pyrolysis vapor from alkaline lignin were sulfur compounds and phenols. Saccharides and ketones were major components of the pyrolysis vapor from MMC, whereas the main compounds in the pyrolysis vapor from larch wood were ketones, phenols, aldehydes, and saccharides. The different composition of the pyrolysis vapor from larch wood and its model mixture was explained on the basis of their different structural frameworks and the non-structural components of larch wood. It was also concluded that the presence of non-structural components, including extractives and ash, affect the pyrolysis reaction of larch wood. Nevertheless, the detailed patterns of this process must be further studied.  相似文献   

14.
One-step and stepwise laboratory batch vacuum pyrolysis of a mixture of birch bark (ca. 46%) and birch sapwood (ca. 54%) was carried out in the temperature range 25–550°C. The pyrolysis oil (defined as the total condensates, including water and organics) was analyzed by GC–MSD and the quantity of phenols (referred to monolignols in this paper) was determined as a function of temperature. The active zone of decomposition and the maximum recovery of phenols were found to be in the temperature range 275–350°C. Distribution of phenols, charcoal and water as a function of temperature was investigated. Stepwise and one-step pyrolysis yielded total phenols of 4.43 and 2.51 wt.% (anhydrous feed basis), respectively. The yields of pyrolysis oil (62.39 wt.%), wood charcoal (23.25 wt.%) and gas ( 14.36 wt.%) produced by both methods were approximately similar, on an anhydrous feed basis.  相似文献   

15.
The study compared the content of eight phenolic acids and four flavonoids and the antioxidant activity of six Polish varietal honeys. An attempt was also made to determine the correlations between the antioxidant parameters of the honeys and their polyphenol profile using principal component analysis. Total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (ABTS) and reduction capacity (FRAP) were determined spectrophotometrically, and the phenolic compounds were determined using high-performance liquid chromatography (HPLC). The buckwheat honeys showed the strongest antioxidant activity, most likely because they had the highest concentrations of total phenols, total flavonoids, p-hydroxybenzoic acid, caffeic acid, p-coumaric acid, vanillic acid and chrysin. The principal component analysis (PCA) of the data showed significant relationships between the botanic origin of the honey, the total content of phenolic compounds and flavonoids and the antioxidant activity of the six Polish varietal honeys. The strongest, significant correlations were shown for parameters of antioxidant activity and TPC, TFC, p-hydroxybenzoic acid, caffeic acid and p-coumaric acid. Analysis of four principal components (explaining 86.9% of the total variance), as a classification tool, confirmed the distinctiveness of the Polish honeys in terms of their antioxidant activity and content of phenolic compounds.  相似文献   

16.
Spices are a popular food of plant origin, rich in various phytochemicals and recognized for their numerous properties. The aim of the study was to evaluate the antioxidant and antimicrobial activity, as well as the content of specialized metabolites, of aqueous extracts of three spice species––garlic (Allium sativum L.), ginger (Zingiber officinalle L.) and turmeric (Curcuma longa L.)––prepared by green extraction methods. Ultrasound treatment increased the chromaticity parameter b value of turmeric and ginger extracts, thus indicating a higher yellow color predominantly due to curcuminoids characteristic of these species. Ultrasound-assisted extraction significantly increased the content of total soluble solids, phenolic compounds, total carotenoids and vitamin C. The temperature of the system was also an important factor, with the highest (70 °C) conditions in ultrasound-assisted extraction having a positive effect on thermolabile compounds (vitamin C, phenolics, total carotenoids). For example, turmeric extract treated with ultrasound at 70 °C had up to a 67% higher vitamin C content and a 69.4% higher total carotenoid content compared to samples treated conventionally at the same temperature, while ginger extracts had up to 40% higher total phenols. All different concentrations of spice extracts were not sufficient for complete inhibition of pathogenic bacterial strains of Salmonella, L. monocytogenes and S. aureus; however, only garlic extracts had an effect on slowing down the growth and number of L. monocytogenes colonies. Spice extracts obtained by ultrasonic treatment contained a significantly higher level of bioactive compounds and antioxidant capacity, suggesting that the extracts obtained have significant nutritional potential and thus a significant possibility for phytotherapeutic uses.  相似文献   

17.
Ultrasound treatment is recognized as a potential technique for improvement in the nutritional values of fruit juices. This study was initiated with the objective of evaluating bioactive compounds and some important quality parameters of black (BC), red (RC) and white (WC) currant juices obtained from fruit mash preliminarily treated by enzymes combined with ultrasound. Individual and total phenolic content (TPC), anthocyanins, color parameters, ascorbic acid, antioxidant capacity (TEAC), juice yield, pH, titratable acidity, and soluble solids were investigated. Significant increases in the levels of TPC and antioxidant capacity of sonicated samples were observed. However, ultrasound treatment had no effect on individual phenolic compounds of juices. Sonication of mash before juice pressing did not cause any noticeable changes in ascorbic acid content. Only in the case of WC was an increase in content of vitamin C noticed. The color of juices obtained after treatment was similar to the control sample. It was demonstrated that enzymatic combined with ultrasound treatment of mash for different colored currant fruit did not have any dismissive effect and could even improve some parameters of the juice obtained.  相似文献   

18.
Solid-phase extraction (SPE) procedures were developed to avoid interference during the quantitative determination of cyproconazole and tebuconazole co-existing in wood extractives. Five species of wood were used, Japanese cedar (Cryptomeria japonica), Japanese larch (Larix leptolepis), Yezo spruce (Picea jezoensis), Sakhalin fir (Abies sachalinensis), and western hemlock (Tsuga heterophylla). Methanol extractives from the heartwood of all wood samples, except western hemlock, interfered with the quantitative determination of cyproconazole and tebuconazole using liquid chromatography (LC) with UV detection (LC-UV). SPE with Oasis MCX was effective in avoiding this interference. This method also reduced the time and volume of mobile phase required for LC-UV, since wood extractives with long retention times were also removed.  相似文献   

19.
The species of the Byrsonima genus (Malpighiaceae) have been used in folk medicine to treat gastrointestinal disorders, asthma and skin infections. In this study, the total phenolic content, antioxidant activity and phytochemical screening were carried out in polar extracts of Byrsonima coccolobifolia, Byrsonima verbascifolia and Byrsonima intermedia. The presence of tannins and flavonoids in the samples and high phenols content was observed. B. coccolobifolia and B. intermedia species showed the best results of antioxidant action. It was analysed the correlation between the methods, and there was a great correlation between phenolic content and antioxidant assay, showing that the phenolic substances contribute to the antioxidant activities of these plants.  相似文献   

20.
Grey alder (Alnus incana (L.) Moench.) wood is often used in the Baltic countries for the production of curing smoke. Unfortunately, the smoke contains an elevated concentration of polycyclic aromatic hydrocarbons (PAH). The effect of the content of wood extractives and the wood storage time after felling on the formation of benzo(a)pyrene (B(a)P), flavouring compounds and antioxidants was studied. Storage time demonstrated a considerable effect on the overall increase of the B(a)P formation. The extraction (elimination) of extractives did not show any definite coherency with the concentration of B(a)P in smoke primary condensates, which was within the range from 1.1 to 8.7 μg/kg. Storage time and the elimination of extractives increased the yields of both 2-hydroxyacetaldehyde and 1,6-anhydro-β,D-glucopyranose (levoglucosan) from 1.8 to 10 times during the pyrolysis process and smouldering. It is interesting that the intensified formation of both substances takes place simultaneously, which commonly does not occur. Nevertheless, the prolonged storage time and the elimination of extractives do not substantially improve the quality of smoke and its condensates.  相似文献   

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