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A continually increasing demand for papermaking materials and simultaneously growing disproportion between the request for fiber and the limited resources of wood have forced scientists and the papermaking industry to search for the new sources of fibrous raw materials. A new promising set of raw materials for papermaking comes from energy crops. This paper presents Sida hermaphrodita Rusby L., as a non-woody raw material for papermaking. From the studies of chemical composition, it follows that cellulose content of more than 40% characterizes phloem of stems and branches, whereas in xylem exhibits more than 32%. The lowest is the concentration of cellulose in leaves and flowers of Sida. The content of lignin is lower than 24% and 16% in stem xylem and phloem, respectively. In Sida, hemicelluloses and mineral substances stand for being not more than 30% and 2%, respectively. The morphology of Sida cells is similar to hardwood, with fiber length of 0.383, 0.470 and 1.025 mm for parenchyma, xylem, and phloem, respectively. The chemical composition of Sida hermaphrodita together with its morphological characteristics make this raw material suitable for a production of papers intended for printing, writing and tissue. [ABSTRACT FROM AUTHOR]

Marine angiosperms could inevitably offer considerable potential resources for their fiber, yet little research has been conducted, especially in Malaysia. Fiber characteristics of five species of seagrass - Enhalus acoroides, Cymodocea serrulata, Thalassia hemprichii, Halophila ovalis, and Halophila spinulosa - were evaluated. Fiber dimensions were studied to determine slenderness ratio, flexibility coefficient, Runkel's ratio, and Luce's shape factor species selection. The seagrass species have the potential in papermaking production as they possessed slenderness ratio >33 (98.12 to 154.08) and high Luce's shape factor (0.77 to 0.83); however the species exhibited low flexibility coefficient <50 (30.07 to 35.18) and >1 Runkel's ratio (1.11 to 1.60), which indicate rigid fiber. The five seagrass species have high cellulose >34% (40.30 to 77.18%) and low lignin content <15% (5.02 to 11.20%), which are similar to those encountered in non-wood plant species. Handmade paper sheet of Enhalus acoroides using pulp subjected to mechanical blending exhibited the highest tensile strength (4.16 kN/m) compared to hand-beaten pulp (3.46 kN/m). The highest breaking length (3.43 km) was achieved by a paper sheet of Thalassia hemprichii using hand-beaten pulp. Based on their physical and chemical composition properties, seagrass have potential as sources of fibrous material for handmade papermaking. [ABSTRACT FROM AUTHOR]

Potent antibacterial activities of solvent extracts (methanol:n-hexane) from the branch, leaf, and root-wood of Salvadora persica were examined against potato phytopathogenic bacteria, namely Pectobacterium carotovorum subsp. carotovorum, Dickeya solani, Ralostonia solanacerum, Enterobacter cloacae, and Bacillus pumilus. The main chemical constituents analyzed by gas chromatography-mass spectrometry (GC/MS) in the branch extracts were N-benzylbenzamide (71.08%), decane (3.17%), stigmasterol (3.17%), 9-desoxo-9-x-acetoxy-3,8,12-tri-O-acetylingol (2.33%), and β-sitosterol (2.15%). The main components in the leaf extracts were 2,6-dimethyl-N-(2-methyl-α-phenylbenzyl)aniline (28.65%), spiculesporic acid (13.60%), homo-γ-linolenic acid (12.63%), and methyl hexadecanoate (11.01%). The rootwood extracts contained, as primary parts, benzeneacetonitrile (71.47%), 4-aminocarbonyl-5-fluoro-1-α-D-ribofuranosyl-imidazole (10.99%), and benzylisothiocyanate (5.05%). The extracts from the root-wood showed moderate antibacterial activity against the potato bacterial pathogens, which was followed by leaf and branch extracts. The results suggested that S. persica plant extracts could be used as bioagents against potato soft and brown rot bacterial pathogens. [ABSTRACT FROM AUTHOR]

Marine angiosperms could inevitably offer considerable potential resources for their fiber, yet little research has been conducted, especially in Malaysia. Fiber characteristics of five species of seagrass – Enhalus acoroides, Cymodocea serrulata, Thalassia hemprichii, Halophila ovalis, and Halophila spinulosa – were evaluated. Fiber dimensions were studied to determine slenderness ratio, flexibility coefficient, Runkel’s ratio, and Luce’s shape factor species selection. The seagrass species have the potential in papermaking production as they possessed slenderness ratio >33 (98.12 to 154.08) and high Luce’s shape factor (0.77 to 0.83); however the species exhibited low flexibility coefficient 1 Runkel’s ratio (1.11 to 1.60), which indicate rigid fiber. The five seagrass species have high cellulose >34% (40.30 to 77.18%) and low lignin content

Taxodium ‘Zhongshansa’ (T. ‘Zhongshansa’) is a hybrid cultivar of the Taxodium Rich. genus. The wood and fiber characteristics and wood chemical compositions of three T. ‘Zhongshansa’ wood specimens were analyzed and compared with their parents, Taxodium mucronatum (T. mucronatum) and Taxodium distichum (T. distichum). It was found that the wood density of the three T. ‘Zhongshansa’ hybrids were slightly lower than the densities of their parents. The average fiber length and length to width ratio of the three samples were similar and greater than their parents. Runkel ratios of the three T. ‘Zhongshansa’ hybrids was smaller than their patents. Compared to the parents, the extractives contents of the three T. ‘Zhongshansa’ hybrids hardly varied, while the lignin content was slightly lower. The result of the kraft cooking and bleaching of T.Z.502 indicated that with a cooking yield of 44.9%, the kappa number of the kraft pulp was 41.8. The T.Z.502 kraft pulp was easier to delignify via oxygen with alkali, and the brightness reached up to 76% ISO after an elemental chlorine free bleaching process. The results provide a reference for the application of T. ‘Zhongshansa’ wood in pulp and paper making in future. [ABSTRACT FROM AUTHOR]

A continually increasing demand for papermaking materials and simultaneously growing disproportion between the request for fiber and the limited resources of wood have forced scientists and the papermaking industry to search for the new sources of fibrous raw materials. A new promising set of raw materials for papermaking comes from energy crops. This paper presents Sida hermaphrodita Rusby L., as a non-woody raw material for papermaking. From the studies of chemical composition, it follows that cellulose content of more than 40% characterizes phloem of stems and branches, whereas in xylem exhibits more than 32%. The lowest is the concentration of cellulose in leaves and flowers of Sida. The content of lignin is lower than 24% and 16% in stem xylem and phloem, respectively. In Sida, hemicelluloses and mineral substances stand for being not more than 30% and 2%, respectively. The morphology of Sida cells is similar to hardwood, with fiber length of 0.383, 0.470 and 1.025 mm for parenchyma, xylem, and phloem, respectively. The chemical composition of Sida hermaphrodita together with its morphological characteristics make this raw material suitable for a production of papers intended for printing, writing and tissue.

Leucaena leucocephala and Casuarina equisetifolia are two fast-growing deciduous tropical hardwoods that were characterized for their morphological and chemical characteristics to assess their suitability for pulp production. The effects of kraft pulping sulfidity, cooking time, and cooking temperature on screened pulp yield and Kappa number were studied. Handsheets made from these pulps showed a vessel picking problem during printing that was reduced by treating the pulp with 0.1% cellulase and beating the pulp at high consistency. [ABSTRACT FROM AUTHOR]

Biomass yield was studied for tall wheatgrass, tall fescue, tall oatgrass, and Miscanthus × giganteus per hectare of cultivation, as well as their calorific value and cost of cultivating these biomasses. Chemical analyses were performed on these raw materials to determine their lignin, cellulose, extractives, and ash contents. The analytical results are compared to the chemical constituents found in birch and pine wood. It was found that the grasses examined in this study differed in biomass yield and cost to cultivate (1 ha plot). Tall wheatgrass, tall fescue, tall oatgrass, and Miscanthus leaves had lower levels of lignin compared with wood, but also lower amounts of cellulose. When determining the cellulose content of these biomasses, the amount of inorganic ash that is bound to them must be taken into account. [ABSTRACT FROM AUTHOR]

Alkali ratios and cooking time of the alkaline sulfite anthraquinone (AQ) and methanol (ASAM) pulping process of bamboo (Gigantochloa scortechinii) were studied. Bamboo chips were cooked at three different levels of sodium hydroxide and cooking time, namely 14, 16, or 18% for 60, 90, or 120 minutes. Pulping parameters that remained constant were the use of 0.5% ethylene diamine tetraacetic acid (EDTA), with an 80/20 ratio Na2SO3/NaOH, 0.1% anthraquinone, 15% methanol, and a temperature of 170℃ in the cooking process. Samples prepared using 14% NaOH and 90 min of cooking time resulted in the highest pulp yield, 52.4%, and a Kappa number of 18.1. It seems that 16% sodium hydroxide and 90 min of cooking time are the most appropriate cooking conditions, giving a 49.1% pulp yield and 14.2 Kappa number. The quality of bamboo pulp produced by the ASAM pulping process was found to be beneficial for the use in paper and board manufacturing. [ABSTRACT FROM AUTHOR]

The radial variation and the genetic variation of wood properties between the parents and offspring of Populus deltoides were studied in this work. The chemical composition, density, and anatomical characteristics of Populus deltoides cl. 'Danhong' and its offspring exhibited the phenomenon of transgressive segregation. The chemical compositions of the parents and offspring were decreased in several attributes (benzene alcohol extract, hemicelluloses, lignin) with the increase of the cambial age. Moreover, the fibre length, fibre width, ratio of fibre length to width, and wall thickness to lumen ratio of parents and offspring were increased with cambial age. In addition, the densities of parents and offspring were increased with the increase of cambial age. There were significant differences in wood properties among Populus deltoides and its hybrids. These results indicated that Populus deltoides cl. 'Danhong' could be considered as pulp material and Populus deltoides cl. 'Nanyang' as building material. According to the radial variation rule of each material character, the rotation cutting period can be selected as years 7 or 8. [ABSTRACT FROM AUTHOR]

The properties of wood can be improved after heat-treatment. There have been many studies dealing with mechanical properties and chemical modifications of heat-treated wood. The purpose of this paper is to provide a new analysis method, to give better insights on the hemicelluloses, cellulose, and lignin contents of heat-treated wood by using Fourier transform infrared (FT-IR) and two-dimensional infrared (2D-IR) spectroscopies. The FT-IR spectra results showed progressive degradation in the carbonyl groups of the glucuronic acid units and degradation of the pyranose of hemicelluloses. These changes were measured as the percentage decrease of crystalline cellulose and the loss of C=O and C=C groups linking together the aromatic skeleton of lignin. The 2D-IR spectra showed the appearance of 5 × 5 peak clusters in the 1000 to 1200 cm-1 region, which could account for the hemicellulose degradation. In addition, changes in the degree of sensitivity at 1627 and 1509 cm-1 coincided with cross-linking reactions among the aromatic units in the lignin molecules. [ABSTRACT FROM AUTHOR]

With high temperature-heat treatment, the dimensional stability and durability of wood is improved and wood color is darkened as well. In this paper, alder birch wood (Betula alnoides) was treated by the Thermo- Vacuum Treatment (TVT). The changes of wood color parameters and the chemical composition were determined by the CIE1976 L*a*b* method and the chemical analysis method, respectively. The results were revealed as follows: (1) A lower value of lightness, L*, and a higher value of total color difference, ΔE*, were obtained at the higher heat-treatment temperatures and longer treatment time. (2) The higher the heat-treatment temperatures and the longer the heat-treatment times were, the lower the contents of hemicellulose and cellulose were and the higher the content of lignin was. Moreover, Fourier Transform infrared spectroscopy (FTIR) analysis demonstrated that the characteristic absorption peaks of cellulose, hemicellulose, and lignin diminished. The acetylation reaction of hemicellulose and the degradation reaction of groups of lignin side chain occurred during TVT. (3) TVT degraded the chemical composition of cell walls, which resulted in further changes of the wood color. A significant correlation existed between the differences of color indices and the differences of the chemical composition after TVT. [ABSTRACT FROM AUTHOR]

Trees provide one of the most versatile biomass resources for many applications, namely wood. The chemical composition of wood determines its properties, being of real significance for its further capitalization, and depending on many factors. In nature, trees' biomass is subjected to considerable pollution stress with further alteration of their normal growth conditions. Some correlations have been established between wood's chemical composition and its further exploitation accordingly to particular circumstances of climate changes and pollution. The content of the main structural polymers from wood, cellulose and lignin, as well other components undergoes notable changes under the influence of pollution phenomena. [ABSTRACT FROM AUTHOR]

Camellia nut shell (CNS) is known as an important bio-resource that has great potential as a biomaterial. The elemental composition, chemical structure, crystallinity, and pyrolysis characteristics were analyzed in this paper for six species of CNS. The concentration of organic carbon, N, K, and Na in CNS ranges from 44.40 to 48.60%, 2.91 to 4.42 mg.g-1, 7.67 to 13.80 mg.g-1, and 0.02 to 0.26 mg.g-1, respectively. The content of lignin, cellulose, hemicellulose, and ash varies between 30.07 and 36.23%, 13.87 and 20.95%, 35.15 and 49.34%, as well as 2.00 and 4.75%, respectively. Camellia nut shell cellulose crystalline structure belongs to typical cellulose type I, and the cellulose crystallinity index for the six species ranges from 37.4 to 62.3%. The CNS pyrolysis process can be divided into three phases, and the substantial degradation occurs within the temperature range of 200 to 430 °C, with nearly 60% loss of weight. The temperature could be reduced greatly during pyrolysis under acidic conditions with PEG 400/glycerol as a solvent. The degradation rate was impacted by K concentration. Increasing cellulose crystallinity negatively affected the degradation rate. [ABSTRACT FROM AUTHOR]

Forest residues are a potentially important source of renewable energy. They are generated as a byproduct of timber harvesting around the world. To optimize the utilization of such biomass, one must know its physical and chemical properties. This paper presents an analysis of comminuted forest residues from Pinus sylvestris L. They were classified into four size fractions for which three density parameters were established pursuant to relevant standards. The mean bulk density of the fractions amounted to 110 to 190 kg/m3, apparent density 725 to 908 kg/m3, and specific density 1111 to 1350 kg/m3. The findings were compared to the results of previous research on other forms of forest biomass. The measured apparent-tospecific density conversion coefficient was ß = 0.64. The elementary composition of forest residues measured in this work differed from that of other biomass types described in literature. In terms of carbon, nitrogen, sulfur, oxygen, and ash content, statistical analysis showed that the two compared types of biomass (forest residues and energy wood chips) formed two separate homogeneous groups, while both of these materials constituted one homogeneous group in the case of hydrogen content. The calorific value of the forest residues was 15.78 ± 0.39 MJ/kg. [ABSTRACT FROM AUTHOR]

Thirteen bamboo species are reported to be in commercial use in Malaysia. However, Buluh madu (Gigantochloa albociliata) did not make to the list. As a species, G. albociliata is cultivated for its delicious bamboo shoot and is demonstrated to possess great potential to produce commercialised products such as laminated bamboo panel. Unlike common bamboo, which has hollow cylindrical culms, G. albociliata has thick culms at the base, with smaller hollow cavities at the top portion. Therefore, it can be easily converted into high-thickness strips, thus improving the processing efficiency of laminated bamboo. To validate this theory, the anatomical, chemical, physical, and mechanical properties of G. albociliata were evaluated. The round bamboo and strips from the top and bottom sections of the bamboo stem were tested. It was found that G. albociliata has a vascular bundle type similar to that of the Gigantochloa genus bamboo. The fibre in G. albociliata is long and strong. The top section of bamboo has longer fibres, a higher density, and a higher specific gravity than the bottom section. As a result, bamboo from the top section has greater bending strength than bamboo from the bottom section. The G. albociliata species was discovered to have high mechanical strength, dimensional stability, and good wettability, making it an ideal material for laminated products. [ABSTRACT FROM AUTHOR]

Vitamin C, enzyme activities, phenolic compounds, antioxidant capacity, antimicrobial activity, and essential oil analyses of ripe and unripe fruits of P. terebinthus were investigated. Vitamin C amounts of ripe and unripe fruits were 63.2 and 15.4 mg/100g, respectively. The main phenolic compounds of unripe and ripe fruits are rutin, syringic acid, and gallic acid. It was determined that the enzyme inhibitor activities in the ripe and unripe fruits were 0.136 mg/mL and 2.14 mg/mL. In all of the free radical scavenging (DPPH and ABTS) activity, ferric (III) ion reducing antioxidant power (FRAP) capacity, total phenolic substance amounts (TPC), total flavonoid substance amounts (TFC), and total antioxidant activity (TAC) antioxidant methods analyzed with plant parts, the methanol extracts obtained from the ripe fruits of the P. terebinthus showed higher antioxidant properties than the methanol extracts obtained from the unripe fruits. Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 showed antimicrobial activity against microorganisms, while methanol extracts obtained from unripe fruit samples did not show antimicrobial activity against the microorganisms used. The chemical grade with the most compounds in the essential oils of P. terebinthus were monoterpenoids, sesquiterpenes, and monoterpenes in unripe and ripe fruits, respectively. The main components were α-pinene with 22.8% and 27.3% ratios in unripe and ripe fruits, respectively. [ABSTRACT FROM AUTHOR]

This study was centered on finding a locally sourced alternative to imported long-fibre pulp for Nigerian pulp and paper mills. Fibre characteristics, chemical composition, and paper properties of pulp handsheets at different levels of kappa number and freeness in the range of 10 oSR and 62 oSR were evaluated using air-dried bast fibre obtained from decorticated kenaf plants grown in southern guinea savanna near Jebba, Nigeria. Kenaf bast fibre compared well with softwood, with an average fibre length of 2.90 mm, a flexibility ratio of 57%, and a Runkel ratio of 0.76. Ash, lignin, and pentosan contents were 0.6%, 12.5%, and 10.6%, respectively, while the cellulose content was 55.5%. Under alkali charge of 15.0 and, sulphidity of 17.5 with constant temperature, cooking time, and liquor-to-fibre ratio of 4.5:1, the screen yield was between 48.8 to 52.8 % with kappa number 12.04 to 20.5. Unbleached pulpsheets at kappa number between 15 and18.5 and pulp freeness 55 oSR and bleached pulp freeness between 148 and 336 mLs had better quality paper in terms of overall pulpsheet strength properties.

Handsheets produced from corn stalks and wheat straw soda AQ pulps were recycled in the lab. Pulping of corn stalks resulted in a low pulp yield, low bonding strength, and low recyclability. Conversely, wheat straw fiber had a better yield, very good tensile properties, and showed a considerably better response to recycling. The tensile index of wheat straw fibers retained 67% of its original value after four cycles. It could be shown that recycling caused only small changes in chemical compo-sition, but that the crystallinity index increased considerably. To be able to understand the behavior of wheat straw fiber as part of a commercial papermaking furnish, a paper containing 20% wheat straw fiber was produced on a 24 inch pilot paper machine and was recycled using a handsheet mold with white water return. Chemical analysis of the control (no wheat fiber) and the wheat-containing paper demonstrated slightly higher xylan content for the wheat-containing material. Recyclability increased slightly with addition of wheat fibers to a commercial furnish.

Potent antioxidant activities of solvent extracts (96% aqueous ethanol) from the fruit, leaf, and branchlet without adherent leaf of Cupressus arizonica were evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and compared with butylated hydroxytoluene (BHT) and ascorbic acid (AA). Their chemical compositions were analyzed using gas chromatography-mass spectrometry (GC/MS). Branchlet extracts (BE) were the most active as an antioxidant agent at 93.3% at the concentration of 0.493 mg/mL, which was higher than the value of vitamin C (63.3%) at the same concentration. The major components identified in the BE were communic acid (43.7%), followed by agatholic acid (20%), and ferruginol (10.4%). The extract from fruit had good antioxidant activity (90.3%) at a concentration of 0.015 mg/mL. The major compounds identified in the fruit extracts (FE) were communic acid (46.8%), spirohexane-5-carboxylic acid, 1,1,2,2-tetramethyl-, methyl ester (27.4%), and ferruginol (6%). Leaf extracts (LE) were more active as an antioxidant agent at 80.3%, which was higher than the value of BHT (75.7%) at the concentration of 0.015 mg/mL. The major components identified in the LE were hexadecanoic acid (45.1%), 1H,5H-pyrrolo[1',2':3,4]imidazo[1,5-a]pyridine, octahydro-(9%), bicyclo [3.1.0]hex-3-en-2-one, 4-methyl-1-(1-methylethyl)-(8.1%). [ABSTRACT FROM AUTHOR]

The effects of SuperBatch™ (SB), CompactCooking™ (CC), and Lo- Solids™ (LS) modified cooking processes on pulp properties of Eucalyptus globulus and Eucalyptus nitens were investigated. The syringyl/guayacil (S/G) lignin ratio in the wood of E. globulus was significantly higher (4.7) than that of E. nitens (3.5). From the brown stock pulps, the viscosity, total lignin, carbohydrate composition, acetone extractives, and hexenuronic acids were measured. For the same Kappa number level (17 ± 0.5), pulps from E. globulus needed lower H-factor. They also presented a higher brightness and more cooking rejects, independent of the cooking method. CC presented a slightly higher cooking yield and pulp viscosity compared to the other modified cooking methods. At the same Kappa number level, the pulps of E. nitens presented a greater amount of total lignin, whereas E. globulus presented a higher amount of hexenuronic acid content, independent of the cooking method. [ABSTRACT FROM AUTHOR]

The antifungal activities and chemical composition of neem seed extract (Azadirachta indica) were investigated. An agar diffusion assay showed that neem seed extract (optimum concentration: 10%) inhibited the growth of Trametes versicolor and Gloeophyllum trabeum. The minimum inhibitory concentration and minimum fungicidal concentration were 2% and 4%, respectively, against the two fungal species. Scanning electron microscopy revealed severe morphological damage to fungal hyphae, including reduction of spores and hyphal shriveling. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry analyses identified 17 compounds that represented 80.3% of the total extract, including astaxanthin (34.3%), cinobufagin (16.9%), anodendroside A (6.65%), 16-acetoxy-4,8,14-trimethyl-3,11-dioxo-, methyl ester (5.09%). Furthermore, T. versicolor-infected wood and G. trabeuminfected wood treated with 10% neem seed extract displayed mass decreases of 11.4 ± 5.8% and 25.8 ± 7.5%, respectively, compared with distilled water treatment (21.6 ± 4.2% and 46.9 ± 4.3%, respectively). These findings suggest the potential use of neem seed extract for antifungal wood protection. [ABSTRACT FROM AUTHOR]

Three kinds of softwoods (Douglas fir, radiata pine, and Sugi) were used to test the possibility of their classification via near infrared (NIR) spectroscopy. In a previous study, the authors presented that the content of Korean softwood extractives (larix, red pine, Korean pine, cedar, and cypress) influenced wood classification. For expanding the extent of wood species to be considered in the analysis, three foreign wood species were newly introduced. Prior to comparing the NIR spectra obtained from the three softwoods, principal component analysis (PCA) was conducted to evaluate the possibility of discriminating the three foreign softwoods. The three species were also divided into three groups based on PCA, and a thin-layer chromatography (TLC) test improved the reliability of NIR-based wood classification via extractive contents. A similar pattern was obtained for alcohol-benzene eluted extractive compounds between same wood species. [ABSTRACT FROM AUTHOR]

Barks of Tachigali guianensis and Tachigali glauca, from the Brazilian Amazon rainforest, were studied regarding anatomy and chemical composition. The barks were similar, with a narrow rhytidome, a ring of sclerified cells below the periderm, a widely dilated and sclerified nonconducting phloem, septate crystal strands, and extensive phenolic deposits in cells. Differences between the species were mainly in the sclerenchyma. Proportions of cell types in the T. guianensis and T. glauca barks were, respectively: 27.8% and 28.3% axial parenchyma, 15.6% and 15.1% sieve tube elements, 11.6% and 13.4% radial parenchyma, 15.6% and 8.7% sclereids, and 30.5% and 34.5% fibers. Chemical analysis showed that the T. guianensis and T. glauca barks included, respectively: 18.0% and 15.3% extractives, 1.8% and 1.0% suberin, 26.8% and 27.9% lignin, and 3.5% and 4.5% ash. The predominant polysaccharides were glucose (72.8% and 82.8% of total neutral sugars) and xylose (17.9% and 11.6%). Ethanol-water extracts were high in phenolics (total phenolics of 441.0 mg gallic acid equivalents (GAE) / g extract and 641.7 mg GAE / g extract), with moderate antioxidant activities (IC50 values of 7.3 μg extract / mL and 5.6 μg extract / mL). Tachigali guianensis bark and, particularly, T. glauca bark may be sources of phenolic compounds. [ABSTRACT FROM AUTHOR]

Changes in chemical composition and structure of corncob lignocellulosic biomass were investigated relative to pretreatment and anaerobic digestion. The pretreatment involved 1% and 3% sodium hydroxide, 3% and 7% sulphuric acid, as well as medium and high temperature extrusion (in 110°C and in the range from 140°C to 160°C). The chemical components content was studied using a gravimetric method, whereas structure and relations between the carbohydrate and lignin participation were investigated using Fourier transform infrared spectroscopy. It was determined that the chemical treatment, both acidic and alkaline, changed the chemical composition of corncob more significantly than the extrusion. Alkaline pretreatment contributed to significant delignification, while acidic pretreatment reduced the share of hemicelluloses and increased the proportion of lignin, the so-called "pseudolignin". The composition of corncob (control and after pre-treatment) was changed after anaerobic digestion, i.e., a decreased carbohydrate substance content and a significantly increased lignin content. FTIR analysis showed changes in their structure. Although the control corncob differed from that processed by various pretreatment methods, the chemical composition of the digested pulp obtained from them was similar. The NaOH pretreatment was judged to be the preferred method for delignification of the raw material. [ABSTRACT FROM AUTHOR]

Corn is a plant that can be used as a potential source of biomass for various biomaterial applications. Thermoplastic corn starch and corn hull, husk, and stalk fibers were extracted from different corn plant parts. The chemical composition, physical properties, thermal stability, crystallinity index, and surface morphology of the extracted samples were characterized on a powder basis. The corn husk and corn starch revealed an excellent combination of properties. Corn husk provided the highest cellulose content as well as the most favorable surface morphology. Corn starch revealed acceptable amylose content and tolerable thermal stability. The cellulose and starch demonstrated an excellent correlation between the function and structure of biomolecules. Hence, both corn starch and husk have potential for use in many applications of the biomaterial. [ABSTRACT FROM AUTHOR]

The use of charcoal and firewood for cooking is common in Zambia, and its utilization is such that the deforestation rate is high, energy utilization is low, and unfavorable cooking methods lead to high death rates due to indoor air pollution mainly from particulate matter and carbon monoxide. By using an alternative cooking method, such as pellet stoves, it is possible to offer a sustainable solution, provided that sustainable pellet production can be achieved. In this study, 12 different available biomaterials were pelletized in a single pellet unit to investigate their availability as raw materials for pellet production in Zambia. The study showed that sicklebush and pigeon pea generated the same pelleting properties correlated with compression and friction and that both materials showed low moisture uptake. The study also identified two groups of materials that broadened the raw material base and helped to achieve sustainable pellet production. Group 1 consisted of materials with equal pelleting abilities (miombo, peanut shell, pigeon pea, and sicklebush) and Group 2 consisted of materials that showed low impact of varying moisture content (eucalyptus, miombo, peanut shell, pigeon pea, and sicklebush). The hardest pellet was made from Tephrosia, which was followed by Gliricidia. [ABSTRACT FROM AUTHOR]

Alkali ratios and cooking time of the alkaline sulfite anthraquinone (AQ) and methanol (ASAM) pulping process of bamboo (Gigantochloa scortechinii) were studied. Bamboo chips were cooked at three different levels of sodium hydroxide and cooking time, namely 14, 16, or 18% for 60, 90, or 120 minutes. Pulping parameters that remained constant were the use of 0.5% ethylene diamine tetraacetic acid (EDTA), with an 80/20 ratio Na2SO3/NaOH, 0.1% anthraquinone, 15% methanol, and a temperature of 170 °C in the cooking process. Samples prepared using 14% NaOH and 90 min of cooking time resulted in the highest pulp yield, 52.4%, and a Kappa number of 18.1. It seems that 16% sodium hydroxide and 90 min of cooking time are the most appropriate cooking conditions, giving a 49.1% pulp yield and 14.2 Kappa number. The quality of bamboo pulp produced by the ASAM pulping process was found to be beneficial for the use in paper and board manufacturing.

Camellia nut shell (CNS) is known as an important bio-resource that has great potential as a biomaterial. The elemental composition, chemical structure, crystallinity, and pyrolysis characteristics were analyzed in this paper for six species of CNS. The concentration of organic carbon, N, K, and Na in CNS ranges from 44.40 to 48.60%, 2.91 to 4.42 mg.g-1, 7.67 to 13.80 mg.g-1, and 0.02 to 0.26 mg.g-1, respectively. The content of lignin, cellulose, hemicellulose, and ash varies between 30.07 and 36.23%, 13.87 and 20.95%, 35.15 and 49.34%, as well as 2.00 and 4.75%, respectively. Camellia nut shell cellulose crystalline structure belongs to typical cellulose type I, and the cellulose crystallinity index for the six species ranges from 37.4 to 62.3%. The CNS pyrolysis process can be divided into three phases, and the substantial degradation occurs within the temperature range of 200 to 430 °C, with nearly 60% loss of weight. The temperature could be reduced greatly during pyrolysis under acidic conditions with PEG 400/glycerol as a solvent. The degradation rate was impacted by K concentration. Increasing cellulose crystallinity negatively affected the degradation rate.

The quantitative comparison of essential oils extracted from various parts of Cupressus funebris and Juniperus chinensis was studied. With increased height, the content of essential oils from branches decreased, while the content of essential oils from leaves increased for both species. A maximum amount of essential oils were found in the west and a minimum in the east of branches and leaves for the two species. Moreover, the content of essential oils in trees with a knot was higher than in those without a knot. The order of essential oil content was as follows: leaf > fine root > coarse root > bark > bough > branch > trunk in C. funebris, and leaf > fine root > bark > coarse root > bough > trunk > branch in J. chinensis. The essential oils extracted from various parts of C. funebris and J. chinensis were analyzed by gas chromatography-mass spectrometry. A total of 67, 33, 69, 65, and 69 components were identified from the roots, trunks, barks, branches, and leaves of C. funebris, respectively. A total of 72, 46, 79, 55, and 82 components were identified from the roots, trunk, bark, branches, and leaves of J. chinensis, respectively. [ABSTRACT FROM AUTHOR]