Volume 14 Issue 3

According to the literature, approximately 41 nutraceutical compounds have been isolated from different types of biomass using green solvents. It is important to collect information on the pharmacokinetic properties of the nutraceutical substances from biomass isolated according to the published papers. The pharmacokinetic properties of the bioactive substances extracted by green solvents, such as the molecular weight, logP, AlogP, H-bond acceptor, H-bond donor, total polar surface area, atom molar refractivity, number of rotatable bonds, number of atoms, rotatable bond count, number of rigid bonds, number of atom rings, and number of H-bonds, were calculated with a drug-likeness tool. In practical terms, the original and most well-known Lipinski’s Rule of Five (Ro5) was applied to 28 substances, namely 3-hydroxytyrosol; apigenin; artemisinin; bergapten; bilobalide; biochanin A; caffeic Acid; caffeoylmalic acid; catechins; cinnamic acid; curcumin; daidzei; daidzin; epicatechin; gallic acid; genistein; ginkgolide A; ginkgolide B; levofloxacin; luteolin; naringenin; p-coumaric acid; protocatechuic acid; psoralen; quercetin; trans-ferulic acid; tyrosol, and vanillin.

High quality North American hardwood lumber and veneer is increasingly exported and used worldwide. A large portion of the timber resource utilized in the production of these products is contained within the northern region of the eastern United States. The cubic volume of this resource has increased by 15% since 2000, with most of this increase occurring in trees greater than 43.2 cm diameter at breast height. Although the volume of high-quality timber is likely at its highest level in over 100 years, 60% of the increase in the volume between 2008 and 2017 was in sawtimber-size (27.9 cm and larger) trees of low quality. Region wide, the species group “other white oaks” had the largest increase in high-quality volume. The largest increases in low-quality volume were for the soft maple and “other red oaks” species groups. While the volume of poletimber (12.7 to 27.7 cm) growing stock decreased between 2008 and 2017, the volume of cull poletimber-size trees increased more than 50%. These trends indicate a future decline in timber quality. Research is needed to determine the cause of these declines and how they may be reversed. One question that should be examined is the role of natural mortality and damage versus human disturbance on timber quality.

Wood-fiber insulation boards can be utilized as a core construction material. They provide a comfortable and safe residential space and reduce energy consumption because of the ecofriendly nature and high heat insulation. In this study, wood-fiber insulation boards were prepared with different types of adhesive (melamine-urea-formaldehyde (MUF), phenol-formaldehyde (PF), emulsifiable 4,4’ methylene diisocyanate (eMDI), and latex resins), and the physical and heat insulation properties, toxic chemical emissions, and combustion characteristics were analyzed. The different adhesive types had no major effects on the insulation. With regard to the toxic emissions, all wood-fiber insulation boards showed the best rating possible except for the PF resin. In the cone-calorimeter test, the wood-fiber insulation board prepared with MUF showed a lower total heat release, mean heat release rate, smoke release, and CO and CO2 yields than the other samples because of the early formation of the carbonized layer. Based on the comprehensive evaluation, the MUF adhesive is the best choice for wood-fiber insulation boards.

The influence of log diameter and log quality were studied relative to the potential heat energy produced from wood residue. Research was conducted on beech sawmill logs (30 cm to 49 cm in diameter and 4 m in length) of different qualities. Logs with greater diameters and of better quality increased the amount of products and decreased the amount of residue. A decrease in the diameter and quality of beech logs increased the total energy capacity, ranging between 840 kWh/m3 (highest quality logs, 40 cm to 49 cm in diameter) and 1,350 kWh/m3 (lower quality logs, 30 cm to 34 cm in diameter). Drying the lumber produced from logs of small diameters used less than 10% of the potential heating energy. However, logs of 40 cm to 49 cm in diameter increased this usage to 33%. When burner losses and drying energy losses were calculated, there was approximately 430 kWh/m3 to 960 kWh/m3 of leftover energy. This could be used for various purposes or it could be sold. The amount of obtained energy was influenced more by log diameter than by the log quality.

This work aimed to investigate the effects of the length of finger-contacted surfaces and oil palm wood densities on bending and compressive properties in the case of finger-jointed oil palm wood products (FJOP). The FJOP were manufactured from oil palm wood raw materials of three different density ranges (303 kg/m3 ± 14 kg/m3, 381 kg/m3 ± 24 kg/m3, and 476 kg/m3 ± 21 kg/m3) using the same finger profile. Polyvinyl acetate was used for bonding. For each density range, FJOP were produced with three different lengths of the finger-contacted surfaces (6 mm, 8 mm, or 10 mm). The length of finger-contacted surfaces did not significantly affect the bending and compressive properties of FJOP for each density range. All examined properties of FJOP increased with oil palm wood density. However, most of the examined properties of FJOP were slightly lower compared with that of solid oil palm wood without the finger joint of the same density. In view of strength, FJOP especially at high density could be used for further processing of cross laminated timber as its original solid wood was used.

Translucent coatings applied to wood that is used for exterior applications often fail because of photodegradation and colonisation by black-stain fungi. This paper reports the effect of silver nanoparticles on the black-stain resistance of acrylic latex coatings. Acrylic latexes that contained various concentrations of silver nanoparticles were mixed with a commercial acrylic resin. The formulations were then applied to red pine (Pinus resinosa) sapwood, which was later evaluated for fungal resistance to Aureobasidium pullulans, Sclerophoma pityophila, and Eppicoccum nigrum. Latexes with silver nanoparticle concentrations as low as 0.03% (total coating formulation weight) were able to limit S. pityophila and E. nigrum growth, while higher concentrations were needed to limit the growth of A. pullulans. The influences of silver nanoparticles on the optical properties of the coating (i.e., colour, opacity, and gloss) were evaluated. It was demonstrated that the addition of silver nanoparticles to the formulation does not compromise the development of a translucent coating.

The addition of nano- and micro-fibrillated cellulose to conventional softwood Kraft pulps can enhance the product performance by increasing the strength properties and enabling the use of less raw material for a given product performance. However, dewatering is a major problem when implementing these materials to conventional paper grades because of their high water retention capacity. This study investigated how vacuum dewatering is affected by different types of additives. The hypothesis was that different types of pulp additions behave differently during a process like vacuum suction, even when the different additions have the same water retention value. One reference pulp and three additives were used in a laboratory-scaled experimental study of high vacuum suction box dewatering. The results suggested that there was a linear relationship between the water retention value and how much water that could be removed with vacuum dewatering. However, the linear relationship was dependent upon the pulp type and the additives. Additions of micro-fibrillated cellulose and dialcohol cellulose to the stock led to dewatering behaviors that suggested their addition in existing full-scale production plants can be accomplished without a major redesign of the wire or high vacuum section.

To enhance the resistance of eucalyptus (EU) reinforced high density polyethylene (HDPE) composites to exposure in simulated seawater, the EU fibers were modified by alkali treatment with NaOH to prepare wood-plastic composites (WPCs). The materials were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), moisture absorption, mechanical properties, and color change tests. After exposure to the sea water, all composites experienced deterioration of water repellency and mechanical properties, and color change. The NaOH concentration greatly influenced the properties of the EU/HDPE composites both before and after exposure. The alkali-treated EU fibers presented low polarities, which resulted in better interfacial bonding, improved mechanical properties, lower moisture absorption, and lower color change relative to the untreated samples after immersion in simulated sea water. The results showed that the HDPE composite prepared with 3% NaOH treated EU fiber had better degradation resistance compared with the untreated composite. The tensile strength, flexural strength, flexural modulus, and impact strength increased 29.9%, 19.8%, 35.4%, and 39.3%, respectively, in comparison with the untreated composite after 21 d exposure. The improved degradation resistance of the alkali-treated EU/HDPE composites could ensure the expected service life of their products and widen their practical applications.

Moisture changes during cyclic fluctuations of relative humidity (RH) usually affects wood service. To investigate the effects of different cyclic patterns of RH fluctuations on wood sorption, Populus euramericana was subjected to three dynamic sorption modes and a static adsorption-desorption loop. Moisture responses were measured automatically. Regarding the sorption amount, the average moisture content (MC), amplitude, and moisture sorption coefficient in a square pattern of humidity change were larger than those obtained from sinusoidal or triangular patterns, but all were less than those experienced in the static humid condition. For the sorption rate, the maximum phase lag was in the square pattern, and the corresponding value from sinusoidal pattern was about 1.5 times of that in the triangular pattern. The greatest dynamic diffusion coefficient (D) was also in square pattern, but less than the static value. Sorption kinetics were characterized by a mathematical model, which indicated that the highest dynamic MC gradient difference between center and surface was lower than that under the static condition, in the following order: square pattern > sinusoidal pattern > triangular pattern. The results could help with understanding the effects of cyclic RH changes on moisture change and the potential deformation during wood service.

The Siamese people utilized the bark of the Coi tree (Streblus asper Lour.) to manufacture paper approximately 330 years ago. However, there are no studies yet related to the chemical properties of Coi bark as well as the morphological properties of Coi bark fiber and Coi pulp fiber. This research paper discussed such properties of Coi bark. The results indicated that Coi bark possessed a chemical composition that could potentially be used for pulp production, although it contained a high value of ash content, due to many calcium particles in the bark. Even though Coi pulp fibers were very long and stiff, with small lumens and thick cell walls, they could be felted naturally on a washing screen to make a strong wet sheet. This was due to a high felting power of fibers derived from a high value of fiber length and slenderness ratio. Therefore, the handsheets produced from Coi pulp fiber were obtained without chemical and beating treatments. These observations mean that both the archaeological and industrial applications of Coi bark, i.e., an ancient Samud Coi preservation and a new potential source of pulp fiber, are possible.