Extraction and Characterization of Pequi Seed Oil for Biodiesel Production: A Green Management of Waste to Biofuel Using Ethanol and Heterogeneous Catalysis

This work reports the characterization of a vegetable oil extracted from pequi seeds, an agroindustrial residue, and its biodiesel production using ethanol and heterogeneous catalysis. The pequi seeds showed 40.73 wt.% of extractive content, which represents a large amount of the biomass composition. The crude oil extracted from the pequi seeds with ethanol as solvent presented a high content of free fatty acids (FFAs), mainly oleic (54.14%) and palmitic (36.71%) acids, resulting in an acidity value of 13.8 ± 0.1 mg KOH g-1. The esterification/transesterification process was performed using two ion exchange resins as heterogeneous catalysts, a commercial protonic form (assigned as PR) and a zirconium-exchanged (assigned as PRZr). Conversions of 87.1 and 91.4% were achieved for PR and PRZr as catalysts, respectively, at optimal conditions (1:6 oil-to-alcohol molar ratio, 25 wt.% of catalyst, 100 ºC and 1 h). These results indicated that heterogeneous acid catalysts can be successfully applied in biodiesel production from fatty acidrich oils, such as the one extracted from pequi seeds. Also, a simultaneous process involving both oil extraction and biodiesel production was tested using PRZr as catalyst (25 wt.% of catalyst and 100 ºC), but due to the greater amount of ethanol necessary for the oil extraction (1:16 oil to alcohol mass ratio) the conversion reached only 51.5% after 5 h. For that reason, this work proposes a two stage system for biodiesel production that integrates oil extraction (stage one) and the esterification/transesterification reaction (stage two) to achieve a greener process, waste-to-bioenergy.

Promising two-row covered cultivars for increasing yield and quality of barley grain in conditions of the southern forest-steppe of Western Siberia

Agroclimatic features of the regions of barley cultivation necessitate the creation and cultivation of cultivars characterized by adaptability to local bioand abiofactors. Such cultivars are able to form a stable high-quality crop regardless of the conditions prevailing during the growing season. The developing of potentially high-yielding cultivars is a priority task of barley breeding in the West Siberian region. Two-row barley is characterized by grain equalization, reduced husk content and increased extractive content, compared to sixrow barley. The aim of the study was to characterize the new promising cultivars of barley (two-row covered group) selected in Omsk Agrarian Scientific Center. The research was conducted in the southern forest-steppe of Western Siberia in 2012-2019. 8 cultivars of coverd two-row barley selected in Omsk Agrarian Scientific Center were studied. There are new promising cultivars among them: Omskiy 100 (included in the Russian State Register in 2019) and Omskiy 101 (sent to the State Registration Service in 2018). The standard cultivar was Omskiy 95 (2007). The biochemical parameters of grain were determined: protein content, crude fat, starch, husk content. Barley selection from 2000 to 2019 focused on the developing of drought-resistant cultivars, which formed increased productivity and quality of grain in dry and arid periods of vegetation in conditions of optimal moistening. New promising cultivars - Omskiy 100 and Omskiy 101 were characterized by the formation of increased indicators of grain quality and productivity in vegetation periods that were contrasting in climatic characteristics. Due to increased yield and grain quality, cv. Omskiy100 had increased protein (+57.91 kg/ha), starch (+0.3 t/ha) and fat (+11.7 kg/ha) harvest compared to the standard. Cv. Omskiy 101 increased protein harvest by 84.9 kg/ha in comparison to the standard.

Surface and Physical Features of Thermo-Mechanically Modified Iroko and Tauari Wood for Flooring Application

The aim of the study was to determine the selected surface and physical properties of iroko (Milicia excelsa (Welw.) C.C. Berg) and tauari (Couratari spp.) wood after thermo-mechanical treatment (TMT) in relation to extractive content. During TMT, no chemicals are introduced into the wood, which distinguishes this method from a number of wood modification methods. The iroko and tauari wood were subjected to volumetric densification in a hydraulic press. The wood was densified in a radial direction at a temperature of 100 and 150 °C. The wood color parameters were measured using the mathematical CIE L*a*b* and L*C*h color space models. The roughness parameters of Ra and Rz parallel and perpendicular to the grain were investigated. The contact angle (CA) of the wood with distilled water was determined based on the sessile drop method. The equilibrium moisture content (EMC) and dimensional changes of the wood were determined for a climate with a temperature of 20 °C and a relative humidity (RH) of 9%, 34%, 55%, 75% and 98%. The tauari wood was less prone to color changes under the influence of TMT than the iroko wood. After densification, the iroko and tauari wood displayed a different character of roughness changes. The iroko wood featured the lowest level of roughness after TMT at 100 °C, and the tauari wood after TMT at 150 °C. The densified iroko and tauari wood were characterized by weaker dynamics in the changes in their respective contact angles than the non-densified wood. The higher the temperature of the TMT, the lower the EMC of the wood. Higher EMC values were observed for the tauari wood than for the iroko wood. This was due to the lower content of chloroform-ethanol extractives. Similar dependencies were obtained in the case of hot water extractives. The thermo-mechanically treated wood displayed a greater tendency towards dimensional changes in a climate with high relative air humidity, i.e., above 70%, compared to the non-modified wood.

Composition of Organic Carbon-Based Compounds in the Stem Wood of Quercus mongolica Seedlings Grown Under Elevated CO2 and/or O3 Concentrations

In this study, we examined the composition of organic constituents of stem woody tissue together with tree growth in Quercus mongolica var. grosseserrata Blume seedlings raised under controlled CO2 and/or O3 concentrations in a Free-Air Concentration Enrichment system. After exposure to ambient air (control), elevated CO2 concentration (550 μmol mol–1 CO2), elevated O3 concentration (double that of the control), and a combination of elevated CO2 and O3 concentrations during a growing season, we measured the diameter and length of stem, and biomass of sampled seedlings and quantified the lignin, extractive, and holocellulose contents of the woody tissue of current-year stems. We confirmed that the growth of seedlings was enhanced under an elevated CO2 concentration condition. In line with this, the extractive content was lower in woody tissue formed under an elevated CO2 concentration than that formed under ambient air, whereas holocellulose content showed an inverse pattern. Elevated O3 concentration itself did not change the organic constituents of the woody tissue, but it reduced the influence of an elevated CO2 concentration. We thus assume that Q. mongolica formed woody tissue with a low extractive content under the high CO2 concentration condition, although this response was possibly mitigated by an elevated O3 concentration. Extractives contains antimicrobial components such as tannins, flavonoids, quinones, and terpenoids. The decrease in extractives within the widely distributed Q. mongolica in East Asia may have a non-negligible impact on C cycling in the future earth with high atmospheric CO2 concentration.

Kalappia celebica, an endemic wood from Sulawesi Island: Chemical composition and its resistance against white rot fungi Ganoderma tsugae and G. lucidium

Kalapi wood (Kalappia celebica kosterm) is endemic to Sulawesi Island and is a monotype species in the Fabaceae family with limited distribution. This study investigates the chemical composition and natural durability of Kalapi (K. celebica Kosterm) wood against white rot fungi Ganoderma tsugae and G. lucidium. This study was conducted based on the TAPPI standard for moisture analysis content, ASTM-D for extractive content, holocelluloce, and lignin, and method Cross and Bevan for cellulose. Durability observation was conducted in 12 weeks by assessing the percentage damage of wood samples caused by the fungi according to SNI standards 01-7207-2014. Results show that K. celebica has holocelullose, cellulose, and extractives at a high level, lignin was moderate, and had low hemicellulose. The results of testing the durability of wood shown that K. celebica has resistance to G. tsugae attack (class II) but is not resistant to G. lucidium (class IV), with an average weight loss of 3.14 % and 18.82 %, respectively.

Specific gravity, Extractive Content, and Natural Durability of Balsa (Ochroma pyramidale) Wood at 3 and 4 years old

The aim was to investigate the specific gravity, extractive content, and natural durability of balsa (Ochroma pyramidale) wood. A total of six trees of balsa at 3 and 4 years old were harvested and cut into the sample of specific gravity, extractive content, and natural durability test. Natural durability was tested according to SNI 01-7207-2006 against dry wood termites (Cryptotermes cynocephalus Light.). Specific gravity, extractive content, mass losses, and termite mortality were measured. Variance analysis was used to find the differences. The results showed that age influenced significantly on specific gravity and mass losses, while axial direction/position influenced significantly on extractive content and mass losses. Variance analysis also showed that radial direction influenced significantly on specific gravity and extractive content. The specific gravity of three years balsa wood is 0.14, which is lower than that of four years old three, which is 0,19. Extractive content in the bottom part (3.95%) is higher than that of in the middle (2.87%) and top (2.74%). Mortality in the bottom part (33.83%) is higher than that of in the middle (10.5%) and top part (5,8%) of the stem. In general, balsa wood is classified into durability class II-III.

The Potential Use of Borassus flabellifer Linn. Color Extract as a Natural Dye

Palmyra (Borassus flabellifer Linn.) palm fruits are bright yellow and have a unique sweet scent. The ripe palm fruits are a rich source of carotenoids which are used as a non-toxic natural dye and have been recognized for their antioxidant benefits. This study aimed to explore the potential of palm fruit extract as a natural coloring agent. The ripe mesocarp of B. flabellifer was extracted using various organic solvents. The carotenoid content, polysaccharide composition, and antioxidant activity of the palm extracts were investigated. The ethanolic palm extract was selected for stability study in various conditions (pH, time, light, and temperature). Then, the extracted nanoemulsion loaded with B. flabellifer extract was formulated and evaluated. The ethanolic extract from the freeze-dried sample yielded high extractive content (42.9%) and showed the greatest antioxidant activity (IC50 2.4 mg/mL). The color intensity of the extract did not fade after exposure to a pH of more than 4. After the storage for 14 days, the color intensity significantly decreased. The light exposure did not influence the color intensity at 25°C. B. flabellifer ethanolic extracted nanoemulsions were successfully prepared by ultrasonication method with the oil to surfactant weight ratio of 1:9. The nanoemulsions loaded with ethanolic extract were stable. The nanoemulsion of the pulp extract could potentially be used as a natural dye.

Termite Resistance, Chemical and Mechanical Characterization of Paulownia tomentosa Wood before and after Heat Treatment

The introduction of new species in forest management must be undertaken with a degree of care, to help prevent the spread of invasive species. However, new species with higher profitability are needed to increase forest products value and the resilience of rural populations. Paulownia tomentosa has an extremely fast growth. The objective and novelty of this work was to study the potential use of young Paulownia trees grown in Portugal by using heat treatment to improve its properties, thereby allowing higher value applications of the wood. The average chemical composition of untreated and heat-treated wood was determined. The extractive content was determined by successive Soxhlet extraction with dichloromethane (DCM), ethanol and water as solvents. The composition of lipophilic extracts was performed by injection in GC-MS with mass detection. Insoluble and soluble lignin, holocellulose and α-cellulose were also determined. Physical (density and water absorption and dimensional stability) and mechanical properties (bending strength and bending stiffness) and termite resistance was also determined. Results showed that extractive content increased in all solvents, lignin and α-cellulose also increased and hemicelluloses decreased. Compounds derived from the thermal degradation of lignin were found in heat-treated wood extractions. Dimensional stability improved but there was a decrease in mechanical properties. Resistance against termites was better for untreated wood than for heat-treated wood, possibly due to the thermal degradation of some toxic extractives.

Dependence of the Concentration of Bioactive Compounds in Origanum vulgare on Chemical Properties of the Soil

The aim of this study was to determine the dependence of the total phenolic, flavonoid, and extractive content in extracts of Origanum vulgare L. on the soil pH, humus, total nitrogen (Ntotal), and plant-available/mobile phosphorus (P2O5), as well as potassium (K2O), total calcium (Ca), magnesium (Mg), and sodium (Na) concentrations. Experimental fields were formed in four locations in Lithuania. Soil and perennial O. vulgare samples were taken at three sites of each experimental field. A total of 12 samples of soil and 12 samples of the tested plant were collected and analyzed. The concentrations of bioactive compounds in plants are significantly (p < 0.05–0.01) affected by some chemical properties of the soil: the total phenolic content was reliably correlated with the soil pH, Ntotal, Ca, Mg, and P2O5; the flavonoid content was correlated with the soil P2O5, K2O, Mg, and Na; and the extractive content was correlated with the soil humus, Ntotal, and Na. The obtained results are useful for the development of the commercial cultivation of O. vulgare.