Translate this page into:
Molecules and functions of rosewood: Dalbergia stevenson
⁎Corresponding author at: School of Forestry, Henan Agricultural University, Zhengzhou 450002, China. pengwanxi@163.com (Wanxi Peng)
-
Received: ,
Accepted: ,
This article was originally published by Elsevier and was migrated to Scientific Scholar after the change of Publisher.
Abstract
In this paper, the organic solvent extract was analyzed by Fourier transform infrared spectroscopy (FT-IR) and gas chromatography–mass spectrometry (GC–MS), TG, Py–GC–MS and TD–GC–MS were used to analyze the Dalbergia stevenson. And then, the pyrolysis products were analyzed by GC–MS. The chromatographic peak area normalization method was used to calculate the groups the relative content of the points. The results show that there are many kinds of bioactive ingredients in the berzolis sandalwood extract, mainly some alcohols and phenolic compounds. And in bio-energy, bio-medicine, cosmetics, skin care products and spices and other fields have potential application prospects.
Keywords
Dalbergia stevenson
Extractives
GC–MS
Py–GC–MS
TD–GC–MS
1 Introduction
With the improvement of living standards, the expectation that returns to nature and green materials is growing. Wood with its unique vision, touch, hearing, environmental and other characteristics, widely favored by the people. Wood, as a special biomass material, has been widely used in agricultural production, construction, furniture, decoration and other aspects. And wood also plays a vital role in the national economy and industrial production. The chemical properties of wood are an important aspect in wood properties and utilization, which affects the physical mechanics of wood, natural durability, wood color, odor, taste and wood processing. Wood has a hygroscopicity, the main reason for the presence of hydrophilic and free hydroxyl groups on cellulose, the variation of its content will affect the moisture absorption of wood, and variation of its content will affect the moisture absorption of wood. In addition to the three elements, the wood also contains a certain type and quantity of extraction material (Raymond, 2002; Sukor et al., 2017). It is closely related to the color, fragrance, taste, natural durability, permeability, wood burning, finishing performance, gluing performance. The type and content of the extract are directly related to the rational utilization of wood (Ateş et al., 2015; Basheer et al., 2017; Razali and Said, 2017).
Wood extractives are substances that can be extracted using polar or non-polar solvents, vapors or water. The wood extract contains a wide variety of organic compounds, there are currently more than 700 kinds, and they can be divided into three categories: terpenoids, aliphatic compounds and phenolic compounds (Nerantzaki et al., 2011; Peng et al., 2015; Hassan et al., 2017). Some of these ingredients are important raw materials for many sectors such as chemical industry, medicine and light chemical industry, and have certain economic value. Wood extracts not only affect the wood itself, but also affect the wood processing technology and the health of the operators (Ge et al., 2015; Ismail and Hanafiah, 2017; Halim and Phang, 2017).
There are obvious differences in the composition and content of extracts, while the same species of wood, extract ingredients and content often have a certain similarity. Therefore, the difference and similarity of chemical composition and content of extract can provide scientific theoretical basis and practical application guidance for wood classification. In order to make full use of resources, reduce environmental pollution and improve the comprehensive utilization of wood, the study of extracts has attracted the attention of researchers both at home and abroad (Peng et al., 2006; Halim et al., 2017; Aziz and Hanafiah, 2017).
Dalbergia stevensonii Tandl English name: Dalbergia stevenson, Belize red sandalwood origin for the Central America, the main production in Belize (Carmenates,2010; Shamsudin et al., 2017; Rahman et al., 2017). However, the use of the Dalbergia stevenson extract has not been studied at home and abroad, and the basic reason is that the Dalbergia stevenson extract resource value is not clear. Therefore, the exploration of the Dalbergia stevenson extract in the high-grade bio-energy, bio-medicine and other high value-added industries potential, which is an effective way to promote the healthy and rapid development of the resources of the Dalbergia stevenson extract, is a reliable guarantee for improving the comprehensive utilization of the Dalbergia stevenson extract, and is also a powerful measure to maximize the economic and environmental effects of the Dalbergia stevenson extract. Correct understanding of wood, understand the nature of wood for wood production and processing, reasonable and efficient use, market circulation and scientific research archaeological are of great significance. The chemical composition and content of extracts based on different types of wood have some differences and similarity, the fingerprints of wood extracts were established by means of fingerprints to study the whole information of wood chemical composition, and it is of great significance to assist in the identification of the same species/wood.
This paper selects Dalbergia stevenson for the study, the organic solvent extracts were analyzed by FT-IR, TG, GC–MS, Py–GC–MS and TD–GC–MS. The spectra of FT-IR, TG, GC–MS, Py–GC–MS and TD–GC–MS were established respectively. By analyzing these extracts, the composition of the extract of Dalbergia stevenson was studied, and the prospect of high grade resource utilization was discussed.
2 Material and methods
2.1 Experimental materials
We named three kinds of extractives as Y1, Y2 and Y3 samples which were extracted by ethanol, ethanol/benzene (1:2), ethanol/methanol (1:1), respectively. After extraction, the solid powder was named Y4, Y5 and Y6 samples which were extracted by ethanol, ethanol/benzene (1:2), ethanol/methanol (1:1), respectively. And the log was named Y0.
2.2 Experimental methods
2.2.1 FT-IR analysis
The FT-IR spectra of the samples were obtained on a FT-IR spectrophotometer (IR100) using KBr discs containing 1.00% finely ground sample (Peng et al., 2014; Xue et al., 2014; Jiang et al., 2017; Khan et al., 2017; Ghafar et al., 2017).
2.2.2 TG analysis
The samples of Diospyros celebica was analyzed by thermogravimetric analyzer (TGA Q50 V20.8 Build 34). The nitrogen release rate was 60 ml/min. The temperature program of TG starts at 30 °C and rises to 250 °C at a rate of 5 °C/min.
2.2.3 GC–MS analysis
GC/MS determination: GC condition: quartz capillary column is 30 mm × 0.25 mm × 0.25 μm, starting at 50 °C, without retention, and then at a rate of 8 °C/min up to 250 °C without retention and then at a rate of 5 °C/min to 300 °C without retention. The temperature of the inlet is 250 °C, column flow is 1.0 ml/min, split ratio is 20:1, and carrier gas is high helium.
MS condition: ionization mode is EI, the electron energy is 70 Ev, the temperature of ion source is 230 °C, the temperature of quadrupole is 150 °C, scan the starting point is 30–600, use the wiley7n.1 standard spectrum and computer search qualitative (Peng et al., 2014).
2.2.4 Py–GC–MS analysis
The powder of Diospyros celebica was analyzed by thermal cracking-gas chromatography–mass spectrometry (CDS5200-trace1310 ISQ). The carrier gas used for high purity helium, the pyrolysis temperature was 500 °C, the heating rate was 20 °C/ms, and the pyrolysis time was 15 s. The pyrolysis product transfer line and the injection valve temperature are set to 300 °C; Column TR-5MS; Capillary column (30 m × 0.25 mm × 0.25 μm); Shunt mode, split ratio of 1:60, shunt rate of 50 ml/min. The temperature of the GC program starts at 40 °C for 2 min, rises to 120 °C at a rate of 5 °C/min, and then rises to 200 °C at a rate of 10 °C/min for 15 min. Ion source (EI) temperature of 280 °C, scanning range of 28–500 amu.
2.2.5 TD-GC–MS analysis
TDS: The initial temperature was 30 °C, reserved for 1 min, at 10 °C/min rate rose to 100 °C, retained 5 min, and then 10 °C/min rate rose to 200 °C, not retained. The transmission line temperature is 230 °C.
GC: quartz capillary column is 30 mm × 0.25 mm × 0.25 um, Starting at 50 °C, without retention, and then at a rate of 8 °C/min up to 250 °C, without retention and then at a rate of 5 °C/min to 300 °C, without retention. Column flow is 1.0 ml/min, split ratio is 20:1, and carrier gas is high helium.
MS: ionization mode is EI, the electron energy is 70 Ev, the temperature of ion source is 230 °C, the temperature of quadrupole is 150 °C, quality range is 30–600 M/Z, use the wiley7n.1 standard spectrum and computer search qualitative (Peng et al., 2012).
3 Results and discussion
3.1 Analysis of FT-IR
The absorption peak of the extract will be greatly disturbed by the three prime elements (cellulose, hemicellulose and lignin). Therefore, the experimental study before and after the extraction of wood powder, through comparative analysis to determine the nature of the extract. According to the relationship between the infrared spectrum of the organic compound and the functional group, the infrared spectrum of Dalbergia stevenson was analyzed. The results are shown in Table 1.
| Absorption peak (cm−1) | Functional group | Chemical composition |
|---|---|---|
| 3387 | O—H Stretching vibration | Cellulose, alcohol, phenol, carboxylic acid compounds |
| 2982 | C—H Stretching vibration | Cellulose |
| 1735 | C⚌O Stretching vibration | Hemicellulose, lipids, ketones |
| 1628 | Aromatic carbon skeleton movement | Lignin |
| 1546 | Aromatic carbon skeleton movement | Lignin |
| 1462 | C—H Bending vibration, CH2, CH3 Asymmetric bending vibration | Lignin, Ether compounds |
| 1455 | CH2 Bending vibration, CH2 Scissor vibration | Lignin, Cellulose |
| 1384 | C—H Bending vibration | Cellulose, Hemicellulose |
| 1343 | S-ring, 5-substituted G-ring | Lignin |
| 1280 | G-ring, Acyloxy CO—O stretching vibration | Lignin |
| 1220 | C—C, C—O Stretching vibration | Lignin |
| 1046 | C—H aromatic in-plane bending vibration | Lignin |
| 881 | C1 | Cellulose |
| 821 | C—H out-of-plane bending vibration | Lignin |
From Table 1 and Figs. 1–3, the characteristic absorption peaks of cellulose showed no obvious peak change at 2982 cm−1, 1455 cm−1, 1384 cm−1 and 881 cm−1, but the absorption intensity decreased, indicating that the cellulose was hydrolyzed in a small amount (Wen et al., 2014; Hony et al., 2000). The absorption peak of the hemicellulose was significantly attenuated at 1381 cm−1, indicating that the hemicellulose fraction was hydrolyzed (Meaurio et al., 2009). Lignin characteristic absorption peaks did not change significantly at 1735 cm−1, 1628 cm−1, 1384 cm−1, 1546 cm−1, 1462 cm−1, 1455 cm−1, 1343 cm−1, 1280 cm−1, 1220 cm−1, 1046 cm−1 and 821 cm−1, but the absorption intensity at 1628 cm−1, 1455 cm−1, 1280 cm−1, and 1046 cm−1 was slightly Weakened, indicating that lignin was partially hydrolyzed after extraction (Hu et al., 2014; Wen et al., 2010; Lourençon et al., 2015; Xu et al., 2013; Rajalingam et al., 2010). The characteristic absorption peak of phenolic compounds appeared at 3387 cm−1, and the absorbance decreased obviously, which indicated that the phenolic compounds were extracted by organic solvent. The phenolic compounds are the main components that affect the color of the wood, which further explains the reasons for the lighter color of the wood after the organic solvent extraction experiment (Xu et al., 2007).
From Fig. 1, it was found that the infrared transmittance of every peak of Dalbergia stevenson after ethanol was changed. The infrared transmittance of Y0, Y1 and Y4 are 63.87%, 29.25% and 81.18%, respectively, at 3367 cm−1. The infrared transmittance of Y0, Y1 and Y4 are 76.94%, 35.91% and 90.40%, respectively, at 2907 cm−1. The infrared transmittance of Y0, Y1 and Y4 are 72.67%, 57.28% and 87.10%, respectively, at 1625 cm−1. The infrared transmittance of Y0, Y1 and Y4 are 71.24%, 61.62% and 87.60%, respectively, at 1450 cm−1. The infrared transmittance of Y0, Y1 and Y4 are 61.62%, 27.00% and 82.78%, respectively, at 1053 cm−1. From Fig. 2, it was found that the infrared transmittance of every peak of Dalbergia stevenson after ethanol/benzene (1:2) was changed. The infrared transmittance of Y0, Y2 and Y5 are 63.87%, 62.72% and 77.32%, respectively, at 3400 cm−1. The infrared transmittance of Y0, Y2 and Y5 are 76.94%, 73.06% and 88.51%, respectively, at 2907 cm−1. The infrared transmittance of Y0, Y2 and Y5 are 72.67%, 67.50% and 84.71%, respectively, at 1625 cm−1. The infrared transmittance of Y0, Y2 and Y5 are 71.24%, 77.34% and 85.32%, respectively, at 1470 cm−1. The infrared transmittance of Y0, Y2 and Y5 are 61.62%, 65.70% and 77.58%, respectively, at 1041 cm−1. From Fig. 3, it was found that the infrared transmittance of every peak of Dalbergia stevenson after ethanol/methanol (1:1) was changed. The infrared transmittance of Y0, Y3 and Y6 are 63.87%, 62.50% and 70.99%, respectively, at 3406 cm−1. The infrared transmittance of Y0, Y3 and Y6 are 76.94%, 73.0% and 87.42%, respectively, at 2907 cm−1. The infrared transmittance of Y0, Y3 and Y6 are 72.67%, 67.55% and 80.96%, respectively, at 1632 cm−1. The infrared transmittance of Y0, Y3 and Y6 are 71.24%, 77.29% and 80.18%, respectively, at 1468 cm−1. The infrared transmittance of Y0, Y3 and Y6 are 61.62%, 65.80% and 72.42%, respectively, at 1041 cm−1.
Comparison of Figs. 1–3 the Dalbergia stevenson after extraction with different solvents, the infrared spectra of extract, extraction powder and log powder have different degrees of change in infrared transmittance. This is mainly due to the different extracts that destroy the different organizational structures of the Dalbergia stevenson, and the extracted substances are also different. And as shown in Figs. 1–3 and Table 1, the absorption peaks of the Dalbergia stevenson extract are mainly concentrated in the wave segments of 3700–3000 cm−1, 3000–2800 cm−1 and 1690–970 cm−1. The main chemical components are phenols, alcohols, ethers, fatty acids, hydrocarbons and aromatic compounds (Balitsky et al., 2004). And the characteristic absorption peaks are reduced, indicating that phenols, alcohols, ethers, fatty acids, hydrocarbons and aromatic compounds are partially extracted.
3.2 Analysis of TG
The thermal stability of Dalbergia stevenson to a large extent determine its excellent flame retardant properties, therefore, the analysis of thermal stability is also an effective way to evaluate the flame retardancy of Dalbergia stevenson. In order to study the thermal stability of Dalbergia stevenson, we conducted a TGA test. T1wt%, T5wt% and Tmax, respectively, for weight loss of 1 wt%, 5 wt% and maximum weight loss rate. T1wt%, T5wt% and Tmax are 41 °C, 60 °C and 45 °C, respectively. From Fig. 4, Dalbergia stevenson's TG mainly goes through three stages. The first stage: from room temperature to 75 °C, mainly Dalbergia stevenson after endothermic evaporation water stage. The second stage: 75–200 °C around, the TG curves of Dalbergia stevenson tends to flatten. The third stage: 200–250 °C or so, this stage is mainly Dalbergia stevenson hemicellulose, cellulose and a small amount of lignin pyrolysis, accompanied by a decrease in weight. The third stage: the thermal degradation rate is increasing, which is mainly due to the degradation of hemicellulose and cellulose in Dalbergia stevenson, resulting in more easily pyrolysis of low molecular carbohydrate, so that the samples are more easily pyrolytic. And between 50 and 250 °C, Dalbergia stevenson heat weight loss is only about 10%, less weight loss, this phenomenon shows that Dalbergia stevenson heat stability is better.
3.3 Analysis of GC–MS
The total ion chromatograms of three kinds of extractives were shown in Figs. 5–7, which were analyzed by GC–MS (see Figs. 8 and 9).
The spectrum of each peak is retrieved by using a computer and wiley7n.1 standard spectrum, according to the laws of the mass spectrum cracking to checking, and peak area normalization method is used to calculate the content of each component, specific results are shown in Tables 2–4.
| No. | Retention time (min) | Peak area (%) | Component |
|---|---|---|---|
| 1 | 12.725 | 1.04 | 1,4-Benzenediol, 2-methoxy- |
| 2 | 15.164 | 0.73 | Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- |
| 3 | 15.287 | 1.63 | 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl-, (E)- |
| 4 | 23.509 | 8.58 | Phenol, 4-methyl-2-[5-(2-thienyl)pyrazol-3-yl]- |
| 5 | 25.514 | 19.25 | 3,3′,4,4′-Tetramethoxystilbene |
| 6 | 26.776 | 9.17 | 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin |
| 7 | 27.008 | 5.15 | 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin |
| 8 | 27.655 | 4.49 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 9 | 28.225 | 1.84 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 10 | 28.613 | 100 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 11 | 28.651 | 16.42 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 12 | 28.755 | 3.67 | Hematoxylin |
| 13 | 29.137 | 4.25 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| No. | Retention time (min) | Peak area (%) | Component |
|---|---|---|---|
| 1 | 12.726 | 1.67 | 1,4-Benzenediol, 2-methoxy- |
| 2 | 15.164 | 0.71 | Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- |
| 3 | 15.287 | 1.3 | 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl-, (E)- |
| 4 | 19.466 | 1.12 | 1,2-Benzenedicarboxylic acid, bis(2-methylpropyl) ester |
| 5 | 20.63 | 0.76 | Dibutyl phthalate |
| 7 | 23.509 | 8.78 | Phenol, 4-methyl-2-[5-(2-thienyl)pyrazol-3-yl]- |
| 12 | 25.501 | 13.54 | 3,3′,4,4′-Tetramethoxystilbene |
| 19 | 26.776 | 9.06 | 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin |
| 23 | 27.649 | 4.96 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 27 | 28.231 | 1.99 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 28 | 28.613 | 100 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 29 | 28.652 | 15.03 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 31 | 28.833 | 2.96 | Hematoxylin |
| 33 | 29.137 | 3.79 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 34 | 29.214 | 0.8 | Hematoxylin |
| No. | Retention time (min) | Peak area (%) | Component |
|---|---|---|---|
| 1 | 9.892 | 0.62 | m-Guaiacol |
| 2 | 12.745 | 4 | 1,4-Benzenediol, 2-methoxy- |
| 3 | 14.498 | 1.38 | 1H-Benzocyclohepten-7-ol, 2,3,4,4a,5,6,7,8-octahydro-1,1,4a,7-tetramethyl-, cis- |
| 4 | 15.164 | 3.24 | Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- |
| 5 | 15.287 | 5.48 | 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl-, (E)- |
| 6 | 17.085 | 0.94 | 7-epi-cis-sesquisabinene hydrate |
| 7 | 22.331 | 0.53 | Dibenz[a,c]cyclohexane, 2,4,7-trimethoxy- |
| 8 | 25.488 | 40.54 | 3,3′,4,4′-Tetramethoxystilbene |
| 9 | 26.446 | 3.81 | 4H-1-Benzopyran-4-one, 2,3-dihydro-5,7-dihydroxy-2-phenyl-, (S)- |
| 10 | 26.75 | 6.77 | 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin |
| 11 | 26.944 | 4.79 | 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin |
| 12 | 27.442 | 39.2 | 4,6-Diamino-3-[4-methoxybenzyl]-1H-pyrazolo[3,4-d]pyrimidine |
| 13 | 27.726 | 12.34 | S-Indacene-1,7-dione, 2,3,5,6-tetrahydro-3,3,4,5,5,8-hexamethyl- |
| 14 | 28.49 | 100 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 15 | 28.548 | 22.05 | 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin |
| 16 | 28.774 | 10.02 | 6a,12a-Dihydro-6H-(1,3)dioxolo(5,6)benzofuro(3,2-c)chromen-3-ol |
According to the results of GC–MS analysis, 35 peaks were detected in Y1, and 13 chemical constituents were identified. The results show that the components are: 1,4-Benzenediol, 2-methoxy- (1.04%), 1,4-Benzenediol, 2-methoxy- (1.04%), Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- (0.73%), 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl-, (E)- (1.63%), Phenol, 4-methyl-2-[5-(2-thienyl)pyrazol-3-yl]- (8.58%), 3,3′,4,4′-Tetramethoxystilbene (19.25%), 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin (9.17%), 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin (5.15%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (4.49%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin(1.84%),10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (100%),10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (16.42%), Hematoxylin (3.67%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (4.25%).
According to the results of GC–MS analysis, 40 peaks were detected in Y2, and 15 chemical constituents were identified. The results show that the components are: 1,4-Benzenediol, 2-methoxy- (1.67%), Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- (0.71%), 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl-, (E)- (1.3%), 1,2-Benzenedicarboxylic acid, bis(2-methylpropyl) ester (1.12%), Dibutyl phthalate (0.76%), Phenol, 4-methyl-2-[5-(2-thienyl)pyrazol-3-yl]- (8.78%), 3,3′,4,4′-Tetramethoxystilbene (13.54%), 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin (9.06%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (4.96%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (1.99%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (100%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (15.03%), Hematoxylin (2.96%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (3.79%), Hematoxylin (0.8%) (see Tables 5 and 6).
| No. | Retention time (min) | Peak area (%) | Component |
|---|---|---|---|
| 1 | 3.554 | 0.64 | Furfural |
| 2 | 5.356 | 1.35 | Benzaldehyde |
| 3 | 5.86 | 1.36 | Cyclotetrasiloxane, octamethyl- |
| 4 | 6.427 | 1.65 | Phenprobamate |
| 5 | 9.906 | 5.33 | m-Guaiacol |
| 6 | 10.372 | 1.13 | Benzene, 1,4-dimethyl-2-(1-methylethyl)- |
| 7 | 10.901 | 2.45 | Resorcinol |
| 8 | 11.809 | 6.29 | Phenol, 2,6-dimethoxy- |
| 9 | 12.25 | 12.23 | Ethanol, 2-(2-butoxyethoxy)-, acetate |
| 10 | 12.363 | 10.7 | 1,2,4-Trimethoxybenzene |
| 11 | 12.817 | 8.9 | 1,4-Benzenediol, 2-methoxy- |
| 12 | 12.88 | 5.68 | Methyleugenol |
| 13 | 13.157 | 4.25 | 1H-3a,7-Methanoazulene, 2,3,4,7,8,8a-hexahydro-3,6,8,8-tetramethyl-, [3R-(3.alpha.,3a.beta.,7.beta.,8a.alpha.)]- |
| 14 | 13.586 | 0.82 | 6-epi-shyobunol |
| 15 | 13.699 | 6.57 | Bicyclo[7.2.0]undec-4-ene, 4,11,11-trimethyl-8-methylene-,[1R-(1R*,4Z,9S*)]- |
| 16 | 13.863 | 7.09 | .alpha.-acorenol |
| 17 | 13.976 | 2.98 | .beta.-Guaiene |
| 18 | 14.102 | 5.95 | 1H-Cycloprop[e]azulene, 1a,2,3,5,6,7,7a,7b-octahydro-1,1,4,7-tetramethyl-, [1aR-(1a.alpha.,7.alpha.,7a.beta.,7b.alpha.)]- |
| 19 | 14.153 | 2.41 | .beta.-Guaiene |
| 20 | 14.291 | 7.11 | Di-epi-.alpha.-cedrene |
| 21 | 14.38 | 16.02 | Naphthalene, 1,2,4a,5,8,8a-hexahydro-4,7-dimethyl-1-(1-methylethyl)-, (1.alpha.,4a.beta.,8a.alpha.)-(.+/−.)- |
| 22 | 14.443 | 4.64 | 1H-Benzocycloheptene, 2,4a,5,6,7,8,9,9a-octahydro-3,5,5-trimethyl-9-methylene-, (4aS-cis)- |
| 23 | 14.493 | 7.15 | .alpha.-Farnesene |
| 24 | 14.556 | 25.73 | 1H-Benzocyclohepten-7-ol, 2,3,4,4a,5,6,7,8-octahydro-1,1,4a,7-tetramethyl-, cis- |
| 25 | 14.682 | 3.17 | .alpha.-acorenol |
| 26 | 14.909 | 4.31 | 1H-Cycloprop[e]azulene, 1a,2,3,5,6,7,7a,7b-octahydro-1,1,4,7-tetramethyl-, [1aR-(1a.alpha.,7.alpha.,7a.beta.,7b.alpha.)]- |
| 27 | 15.048 | 7.86 | 1H-Benzocycloheptene, 2,4a,5,6,7,8,9,9a-octahydro-3,5,5-trimethyl-9-methylene-, (4aS-cis)- |
| 28 | 15.274 | 88.93 | Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- |
| 29 | 15.363 | 11.32 | 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl- |
| 30 | 16.157 | 1.63 | 2-[4-methyl-6-(2,6,6-trimethylcyclohex-1-enyl)hexa-1,3,5-trienyl]cyclohex-1-en-1-carboxaldehyde |
| 31 | 16.434 | 1.02 | 1-Heptatriacotanol |
| 32 | 16.61 | 5.57 | Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- |
| 33 | 16.913 | 1.21 | 1-Heptatriacotanol |
| 34 | 17.115 | 6.89 | Corymbolone |
| 35 | 17.379 | 0.56 | 1-Heptatriacotanol |
| 36 | 19.547 | 100 | 1,2-Benzenedicarboxylic acid, bis(2-methylpropyl) ester |
| 37 | 22.383 | 2.81 | Dibenz[a,c]cyclohexane, 2,4,7-trimethoxy- |
| 38 | 26.895 | 95.34 | Homopterocarpin |
| 39 | 28.155 | 35.59 | 4H-1-Benzopyran-4-one, 2-(3,4-dimethoxyphenyl)-7-hydroxy- |
| No. | Retention time (min) | Peak area (%) | Component |
|---|---|---|---|
| 1 | 4.08 | 8.23 | Carbamic acid, monoammonium salt |
| 2 | 4.35 | 4.62 | 2-Butanone |
| 3 | 4.69 | 6.59 | Acetaldehyde, hydroxy- |
| 4 | 5.01 | 7.23 | Ammonium acetate |
| 5 | 5.19 | 0.54 | 2-Butenal |
| 6 | 5.33 | 2.53 | 2-Propanone, 1-hydroxy- |
| 7 | 5.51 | 0.65 | Methyl Alcohol |
| 8 | 6.87 | 3.04 | 1,2-Ethanediol, monoacetate |
| 9 | 7.39 | 2.51 | Propanoic acid, 2-oxo-, methyl ester |
| 10 | 8.75 | 2.27 | Furfural |
| 11 | 10.2 | 0.72 | 4-Hexen-2-one |
| 12 | 11.16 | 0.77 | Styrene |
| 13 | 11.93 | 0.43 | 2-Pentene, 4,4′-oxybis- |
| 14 | 12.48 | 0.70 | 2(5H)-Furanone |
| 15 | 13.03 | 2.11 | 1,2-Cyclopentanedione |
| 16 | 14.66 | 1.21 | Butanedioic acid, cyclic hydrazide |
| 17 | 15.22 | 0.66 | Phenol |
| 18 | 15.95 | 0.55 | 2H-Pyran-2,6(3H)-dione |
| 19 | 16.33 | 3.88 | N-Butyl-tert-butylamine |
| 20 | 17.15 | 0.76 | 2-Cyclopenten-1-one, 2-hydroxy-3-methyl- |
| 21 | 19.22 | 1.19 | p-Cresol |
| 22 | 19.75 | 3.60 | Phenol, 2-methoxy- |
| 23 | 20.65 | 0.25 | 2,4-Dimethylanisole |
| 24 | 21.45 | 0.24 | 2-Cyclopenten-1-one, 3-ethyl-2-hydroxy- |
| 25 | 24.74 | 0.30 | 2-Methoxy-5-methylphenol |
| 26 | 25.52 | 5.18 | Creosol |
| 27 | 25.81 | 2.15 | trans-2,3-Epoxynonane |
| 28 | 29.04 | 1.94 | Phenol, 4-ethyl-2-methoxy- |
| 29 | 30.94 | 5.47 | 2-Methoxy-4-vinylphenol |
| 30 | 33.07 | 4.02 | Phenol, 2-methoxy-3-(2-propenyl)- |
| 31 | 33.55 | 0.56 | Phenol, 2-methoxy-4-propyl- |
| 32 | 35.36 | 1.91 | Phenol, 2-methoxy-4-(1-propenyl)- |
| 33 | 36.62 | 2.44 | 1,2,4-Trimethoxybenzene |
| 34 | 36.75 | 4.25 | Phenol, 2-methoxy-4-(1-propenyl)- |
| 35 | 38.31 | 1.03 | 5-tert-Butylpyrogallol |
| 36 | 38.8 | 1.30 | Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- |
| 37 | 39.14 | 2.18 | 3′,5′-Dimethoxyacetophenone |
| 38 | 39.69 | 0.47 | Phenol, 2,6-dimethoxy-4-(2-propenyl)- |
| 39 | 41.24 | 1.47 | Phenol, 2,6-dimethoxy-4-(2-propenyl)- |
| 40 | 43.02 | 0.50 | 1H-Indene-4-carboxylic acid, 2,3-dihydro-1,1-dimethyl-, ethyl ester |
| 41 | 43.67 | 2.57 | Tricyclo[4.4.0.0(2,7)]dec-8-ene-3-methanol, à,à,6,8-tetramethyl-, stereoisomer |
| 42 | 43.95 | 0.53 | ë-Selinene |
| 43 | 44.09 | 0.77 | n-Hexadecanoic acid |
| 44 | 46.3 | 1.82 | trans-13-Octadecenoic acid |
| 45 | 46.6 | 0.30 | Octadecanoic acid |
| 46 | 46.69 | 0.25 | Androst-5,7-dien-3-ol-17-one |
| 47 | 46.97 | 0.35 | 13-Methylpentadec-14-ene-1,13-diol |
| 48 | 47.31 | 1.38 | Benzene, 1,1′-(1-methylethylidene)bis[4-methoxy- |
| 49 | 47.75 | 0.64 | Phenol, 4-methyl-2-[5-(2-thienyl)pyrazol-3-yl]- |
| 50 | 53.55 | 0.96 | Dehydroabietic acid |
According to the results of GC–MS analysis, 68 peaks were detected in Y3, and 16 chemical constituents were identified. The results show that the components are: m-Guaiacol (0.62%), 1,4-Benzenediol, 2-methoxy- (4%), 1H-Benzocyclohepten-7-ol,2,3,4,4a,5,6,7,8-octahydro-1,1,4a,7-tetramethyl-,cis- (1.38%), Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- (3.24%), 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl-, (E)- (5.48%), 7-epi-cis-sesquisabinene hydrate (0.94%), Dibenz[a,c]cyclohexane, 2,4,7-trimethoxy- (0.53%), 3,3′,4,4′-Tetramethoxystilbene (40.54%), 4H-1-Benzopyran-4-one, 2,3-dihydro-5,7-dihydroxy-2-phenyl-, (S)- (3.81%), 10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin(6.77%),10,11-Dihydro-10-hydroxy-2,3-dimethoxydibenz(b,f)oxepin (4.79%), 4,6-Diamino-3-[4-methoxybenzyl]-1H-pyrazolo[3,4-d]pyrimidine (39.2%), S-Indacene-1,7-dione, 2,3,5,6-tetrahydro-3,3,4,5,5,8-hexamethyl- (12.34%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (100%), 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin (22.05%), 6a,12a-Dihydro-6H-(1,3)dioxolo(5,6)benzofuro(3,2-c)chromen-3-ol (10.02%).
As can be seen from Table. 2, the Y1 samples were identified thirteen kinds of components totally. Obviously, the representative compound are 3,3′,4,4′-Tetramethoxystilbene, 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f) oxepin. Table 2 showed that Y2 samples were identified fifteen kinds of components totally. Obviously, the representative compound are 3,3′,4,4′-Tetramethoxystilbene, 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f) oxepin. According to Table 3, Y3 samples were identified sixteen kinds of components totally. Obviously, the representative compound are 3,3′,4,4′-Tetramethoxystilbene, 4,6-Diamino-3-[4-methoxybenzyl]-1H-pyrazolo[3,4-d] pyrimidine, S-Indacene-1,7-dione, 2,3,5,6-tetrahydro-3,3,4,5,5,8-hexamethyl-, 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f)oxepin, 6a,12a-Dihydro-6H- (1,3)dioxolo(5,6)benzofuro(3,2-c)chromen-3-ol.
Consequently, three different methods to extract showed that the 3,3′,4,4′-Tetramethoxystilbene, 10,11-Dihydro-10-hydroxy-2,3,6-trimethoxydibenz(b,f) oxepin are representative compound in Dalbergia stevenson.
3.4 Analysis of TD–GC–MS
According to the results of TD–GC–MS analysis, 39 chemical constituents were identified in 87 peaks of Dalbergia stevenson volatiles. The results show that the components are: Furfural (0.64%), Benzaldehyde (1.35%), Cyclotetrasiloxane, octamethyl- (1.36%), Phenprobamate (1.65%), m-Guaiacol (5.33%), Benzene, 1,4-dimethyl-2-(1-methylethyl)- (1.13%), Resorcinol (2.45%), Phenol, 2,6-dimethoxy- (6.29%), Ethanol, 2-(2-butoxyethoxy)-, acetate (12.23%), 1,2,4-Trimethoxybenzene (10.7%), 1,4-Benzenediol, 2-methoxy- (8.9%), Methyleugenol (5.68%), 1H-3a,7-Methanoazulene, 2,3,4,7,8,8a-hexahydro-3,6,8,8-tetramethyl-, [3R-(3.alpha.,3a.beta.,7.beta.,8a.alpha.)]- (4.25%), 6-epi-shyobunol (0.82%), Bicyclo[7.2.0]undec-4-ene, 4,11,11-trimethyl-8-methylene-,[1R-(1R∗,4Z,9S∗)]- (6.57%), .alpha.-acorenol (7.09%), .beta.-Guaiene (2.98%), 1H-Cycloprop[e]azulene, 1a,2,3,5,6,7,7a,7b-octahydro-1,1,4,7-tetramethyl-, [1aR-(1a.alpha.,7.alpha.,7a.beta.,7b.alpha.)]- (5.95%), .beta.-Guaiene (2.41%), Di-epi-.alpha.-cedrene (7.11%), Naphthalene, 1,2,4a,5,8,8a-hexahydro-4,7-dimethyl-1-(1-methylethyl)-, (1.alpha.,4a.beta.,8a.alpha.)-(.+/−.)- (16.02%), 1H-Benzocycloheptene, 2,4a,5,6,7,8,9,9a-octahydro-3,5,5-trimethyl-9-methylene-, (4aS-cis)- (4.64%), .alpha.-Farnesene (7.15%), 1H-Benzocyclohepten-7-ol, 2,3,4,4a,5,6,7,8-octahydro-1,1,4a,7-tetramethyl-, cis- (25.73%), .alpha.-acorenol (3.17%), 1H-Cycloprop[e]azulene, 1a,2,3,5,6,7,7a,7b-octahydro-1,1,4,7-tetramethyl-, [1aR-(1a.alpha.,7.alpha.,7a.beta.,7b.alpha.)]- (4.31%), 1H-Benzocycloheptene, 2,4a,5,6,7,8,9,9a-octahydro-3,5,5-trimethyl-9-methylene-, (4aS-cis)- (7.86%), Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- (88.93%), 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl- (11.32%),2-[4-methyl-6-(2,6,6-trimethylcyclohex-1-enyl)hexa-1,3,5-trienyl]cyclohex-1-en-1-carboxaldehyde (1.63%), 1-Heptatriacotanol (1.02%), Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- (5.57%), 1-Heptatriacotanol (1.21%), Corymbolone (6.89%), 1-Heptatriacotanol (0.56%), 1,2-Benzenedicarboxylic acid, bis(2-methylpropyl) ester (100%), Dibenz[a,c]cyclohexane, 2,4,7-trimethoxy- (2.81%),Homopterocarpin (95.34%), 4H-1-Benzopyran-4-one, 2-(3,4-dimethoxyphenyl)-7-hydroxy- (35.59%).
The volatile components of Dalbergia stevenson include alkanes, phenols, alcohols, terpenes (alkenes), acids, ketones, pyrimidines and so on. Included acetic acid, phenol and its derivatives, and benzene and its derivatives, which could inhibit fungal growth. But phenol, benzene, and their derivatives are toxic. And the higher content of volatile matter in Dalbergia stevenson are Ethanol, 2-(2-butoxyethoxy)-, acetate (12.23%), 1,2,4-Trimethoxybenzene (10.7%), 1,4-Benzenediol, 2-methoxy- (8.9%), Methyleugenol (5.68%), Bicyclo[7.2.0]undec-4-ene, 4,11,11-trimethyl-8-methylene-,[1R-(1R∗,4Z,9S∗)]- (6.57%), .alpha.-acorenol (7.09%), 1H-Cycloprop[e]azulene, 1a,2,3,5,6,7,7a,7b-octahydro-1,1,4,7-tetramethyl-, [1aR-(1a.alpha.,7.alpha.,7a.beta.,7b.alpha.)]- (5.95%), Di-epi-.alpha.-cedrene (7.11%), Naphthalene, 1,2,4a,5,8,8a-hexahydro-4,7-dimethyl-1-(1-methylethyl)-, (1.alpha.,4a.beta.,8a.alpha.)-(.+/−.)- (16.02%), .alpha.-Farnesene (7.15%), 1H-Benzocyclohepten-7-ol, 2,3,4,4a,5,6,7,8-octahydro-1,1,4a,7-tetramethyl-, cis- (25.73%), 1H-Benzocycloheptene, 2,4a,5,6,7,8,9,9a-octahydro-3,5,5-trimethyl-9-methylene-, (4aS-cis)- (7.86%), Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- (88.93%), 1,6,10-Dodecatrien-3-ol, 3,7,11-trimethyl- (11.32%), 1-Heptatriacotanol (1.02%), Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- (5.57%), Dibenz[a,c]cyclohexane, 2,4,7-trimethoxy- (2.81%), Homopterocarpin (95.34%), 4H-1-Benzopyran-4-one, 2-(3,4-dimethoxyphenyl)-7-hydroxy- (35.59%), respectively.
3.5 Analysis of Py–GC–MS
According to the results of Py–GC–MS, 50 compounds were identified, and the peak area accounted for 88.1% of the total peak area, of which the content was higher: Carbamic acid, monoammonium salt (8.23%), 2-Butanone (4.62%), Acetaldehyde, hydroxy- (6.59%), Ammonium acetate (7.23%), 2-Propanone, 1-hydroxy- (2.53%), 1,2-Ethanediol, monoacetate (3.04%), Propanoic acid, 2-oxo-, methyl ester (2.51%), Furfural (2.27%), 1,2-Cyclopentanedione (2.11%), Butanedioic acid, cyclic hydrazide (1.21%), N-Butyl-tert-butylamine (3.88%), p-Cresol (1.19%), Phenol, 2-methoxy- (3.60%), Creosol (5.18%), trans-2,3-Epoxynonane (2.15%), Phenol, 4-ethyl-2-methoxy- (1.94%), 2-Methoxy-4-vinylphenol (5.47%), Phenol, 2-methoxy-3-(2-propenyl)- (4.02%), Phenol, 2-methoxy-4-(1-propenyl)- (1.91%), 1,2,4-Trimethoxybenzene (2.44%), Phenol, 2-methoxy-4-(1-propenyl)- (4.25%), 5-tert-Butylpyrogallol (1.03%), Benzene, 1,2,3-trimethoxy-5-(2-propenyl)- (1.30%), 3′,5′-Dimethoxyacetophenone (2.18%), Phenol, 2,6-dimethoxy-4-(2-propenyl)- (1.47%), Tricyclo[4.4.0.0(2,7)]dec-8-ene-3-methanol, à,à,6,8-tetramethyl-, stereoisomer (2.57%), trans-13-Octadecenoic acid (1.82%), Benzene, 1,1′-(1-methylethylidene)bis[4-methoxy- (1.38%). Obviously, the representative compound is Carbamic acid, monoammonium salt.
4 Conclusion
As can be seen from the above research, the Dalbergia stevenson after extraction with different solvents, the infrared spectra of extract, extraction powder and log powder have different degrees of change in infrared transmittance. The absorption peaks of the Dalbergia stevenson extract are mainly concentrated in the wave segments of 3700–3000 cm−1, 3000–2800 cm−1 and 1690–970 cm−1. The main chemical components are phenols, alcohols, ethers, fatty acids, Hydrocarbons and aromatic compounds. And the characteristic absorption peaks are reduced, indicating that phenols, alcohols, ethers, fatty acids, hydrocarbons and aromatic compounds are partially extracted.
The TG test showed that only a small amount of hemicellulose, cellulose and lignin were pyrolyzed at 250 °C or below, and the thermal stability was better with the decrease of weight. In the GC–MS test, 11 kinds of chemical constituents were identified from the extract of Dalbergia stevenson ethanol. The extract of the Dalbergia stevenson ethanol/benzene (1:2) was 40 peaks, 15 compounds were identified, and 68 peaks were isolated from TD–GC–MS the ethanol/methanol (1:1) extract of the Dalbergia stevenson, and 16 compounds were identified. In, Dalbergia stevenson volatiles were isolated from the 87 peaks and 39 compounds were identified. In Py–GC–MS, 50 compounds were identified in the Dalbergia stevenson.
Acknowledgments
This research was supported by the Planned Science and Technology Project of Hunan Province, China (No. 2016SK2089; No. 2016RS2011), Major scientific and technological achievements transformation projects of strategic emerging industries in Hunan Province (2016GK4045), Academician reserve personnel training plan of lift engineering technical personnel of Hunan Science and Technology Association (2017TJ-Y10).
References
- Chemical contents and antifungal activity of some durable wood extractives vs. Pleurotus ostreatus. Bioresources. 2015;10(2):2433-2443.
- [Google Scholar]
- The potential of palm oil mill effluent (POME) as a renewable energy source. Acta Sci. Malaysia. 2017;1(2):09-11.
- [Google Scholar]
- IR spectroscopy of natural and synthetic amethysts in the 3000–3700 cm−1 region and problem of their identification. Dokl. Earth. Sci.. 2004;394(1):120-123.
- [Google Scholar]
- A study on water quality from Langat River, Selangor. Acta Sci. Malaysia. 2017;1(2):01-04.
- [Google Scholar]
- Carmenates, O.A., 2010. Honduras rosewood: its endangerment and subsequent impact on the percussion industry. Dissertations & Theses – Gradworks.
- Study on antibacterial molecular drugs in Eucalyptus granlla wood extractives by GC-MS.Pak. J. Pharm. Sci.. 2015;28(Suppl. 4):1445-1448.
- [Google Scholar]
- Total phenolic content and total flavonoid content in moringa oleifera seed. Sci. Heritage J.. 2017;1(1):23-25.
- [Google Scholar]
- Comparison between measured traffic noise in Klang Valley, Malaysia and existing prediction models. Eng. Heritage J.. 2017;1(2):10-14.
- [Google Scholar]
- Salicylic acid mitigates pb stress in Nicotiana tabacum. Sci. Heritage J.. 2017;1(1):16-19.
- [Google Scholar]
- Influence of seed loads on start up of modified anaerobic hybrid baffled (MAHB) reactor treating recycled paper wastewater. Eng. Heritage J.. 2017;1(2):05-09.
- [Google Scholar]
- The C-H out-of-plain bending modes of PAH molecules in astrophysical environments. Iso Beyond Peaks. 2000;370(3):1030-1043.
- [Google Scholar]
- Carbon-carbon bond cleavage and rearrangement of benzene by a trinuclear titanium hydride. Nature. 2014;512(7515):413.
- [Google Scholar]
- Management of end-of-life electrical and electronic products: the challenges and the potential solutions for management enhancement in developing countries context. Acta Sci. Malaysia. 2017;1(2):05-08.
- [Google Scholar]
- Treating n-butane by activated carbon and metal oxides. Toxicol. Environ. Chem. 2017:1-12.
- [Google Scholar]
- Comparative diagnosis of typhoid fever by polymerase chain reaction and widal test in Southern Districts (Bannu, LakkiMarwat And D.I.Khan) of Khyber Pakhtunkhwa, Pakistan. Acta Sci. Malaysia. 2017;1(2):12-15.
- [Google Scholar]
- Hardwood and softwood kraftlignins fractionation by simple sequential acid precipitation. Sep. Purif. Technol.. 2015;154:82-88.
- [Google Scholar]
- Analysis of the C=O Stretching Band of the α-Crystal of Poly(l-lactide) Nat. Publ. Group. 2009;42(15):5717-5727.
- [Google Scholar]
- Novel determination of the total phenolic content in crude plant extracts by the use of1H NMR of the –OH spectral region. Anal. Chim. Acta. 2011;688(1):54-60.
- [Google Scholar]
- TD-GC-MS analysis on thermal release behavior of poplar composite biomaterial under high temperature. J. Comput. Theor. Nanosci.. 2012;9(9):1431-1433.
- [Google Scholar]
- Determination of chemical components of cold water extractives of E. urograndis by GC/MS. Trans. China Pulp Paper. 2006;21(4):11-13.
- [Google Scholar]
- Immune effects of extractives on bamboo biomass self-plasticization. Pak. J. Pharm. Sci.. 2014;27(Suppl. 4):991-999.
- [Google Scholar]
- Characteristics of antibacterial molecular activities in poplar, wood extractives. Saudi. J. Biol. Sci.. 2015;24(2):399.
- [Google Scholar]
- Validation of microscopic dynamics of grouping pedestrians behavior: from observation to modeling and simulation. Eng. Heritage J.. 2017;1(2):15-18.
- [Google Scholar]
- Self-assembled monolayers of benzylmercaptan and para-cyanobenzylmercaptan on gold: surface infrared spectroscopic characterization. Phys. Chem. Chem. Phys.. 2010;12(17):4390-4399.
- [Google Scholar]
- Red pigment production by monascuspurpureus in stirred-drum bioreactor. Sci. Heritage J.. 2017;1(1):13-15.
- [Google Scholar]
- Tight repression of elastase strain K overexpression by Pt7 (A1/O4/O3) shuttle expression system. Sci. Heritage J.. 2017;1(1):20-22.
- [Google Scholar]
- Analysis of passengers’ access and egress characteristics to the train station. Eng. Heritage J.. 2017;1(2):01-04.
- [Google Scholar]
- Understanding the chemical and structural transformations of lignin macromolecule during torrefaction. Appl. Energy. 2014;121(10):1-9.
- [Google Scholar]
- Structural characterization of alkali-extractable bamboo lignin: an nmrprespective. J. Biobased Mater. Bioenergy. 2010;4(4):408-425.
- [Google Scholar]
- FTIR and XPS analysis of the changes in bamboo chemical structure decayed by white-rot and brown-rot fungi. Appl. Surf. Sci.. 2013;280(8):799-805.
- [Google Scholar]
- Effect of heat treatment on the phenolic compounds and antioxidant capacity of citrus peel extract. Irish. J. Agric. Food Res.. 2007;55(2):330-335.
- [Google Scholar]
- Molecular bonding characteristics of self-plasticized bamboo composites. Pak. J. Pharm. Sci.. 2014;27(Suppl. 4):975.
- [Google Scholar]