Pulp Samples Research Articles

Nutritional Properties of Baobab Pulp from Different Angolan Origins.

The baobab tree (Adansonia digitata L.) is found widely in the forests and savannas of sub-Saharan Africa. The baobab fruit has a sour and slightly sweet taste and is widely consumed by the natives, thus containing a high nutritional value and providing a source of income for rural people. This study aimed to compare the nutritional composition of baobab fruit pulp from different localities in the Namibe province (Angola). Twenty samples of baobab pulp were collected in markets of the four municipalities of Namibe. The results obtained showed that there is some geographic location dependence on nutritional and functional composition. The municipality of Camucuio showed samples with higher fibre content (56.62 g/100 g) and vitamin C (288.9 mg/100 g). Samples from the Virei municipality stood out for their antioxidant activity (1936 mmol TE/100 g), high K content (42.4 mg/g) and higher values of protein (2.42 g/100 g). The samples collected in the municipality of Bibala stood out for their high contents of carbohydrates (28.1 g/100 g), total phenolic compounds (972 mg GAE/100 g) and Ca (3.80 mg/g). Despite the differences in origin, the high nutritional value of baobab fruit has the potential to improve the diet of thousands of people in Africa qualitatively.

Impact of residual extractives on the thermal stability of softwood Kraft pulp

Wood extractives are known to cause problems during the production of pulp and paper and to impact their mechanical properties. In the present work, we systematically explored whether minute residual amounts of extractives that reprecipitate on the fiber surface in the final stages of the pulping process would lower the thermal resilience of softwood Kraft pulp. Pulp samples subjected to different extraction methods were characterized by means of thermogravimetric analysis. The compound classes constituting the respective extracts were identified and quantified via gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID) and the influence of the individual compound classes on the thermal stability of the samples was investigated separately. Soxhlet extraction with an ethanol/toluene solvent system clearly led to increased thermal stability. Besides fatty acids and resin acids also sterols and sterol esters that do not carry carboxylic acid functionalities contributed to the deterioration of the thermal pulp properties. Lateral order indices derived from Fourier transformed infrared spectra and crystallinity indices derived from solid-state 13C nuclear magnetic resonance spectra indicate that upon thermal degradation, the presence of even minute amounts of extractives leads to an increased degree of supramolecular disorder. Moreover, the characterization of the samples’ carbohydrate composition by means of acidic hydrolysis showed a tendency towards facilitated pyrolysis of the hemicelluloses if extractives were present in the pulp.

RESEARCH OF BURNING OF AGRICULTURAL PELLETS IN BOILERS WITH CAPACITY UP TO 25 kW

The main purpose of this research is to determine the main dependence’s of the agricultural pellets combustion process and to study the influence of regime parameters on the distribution of temperatures in the combustion chamber, as well as to analyze the biofuels productivity characteristics.
 Research methods: experimental and theoretical.
 Results. The research of biofuel combustion process was carried out at the experimental facility of solid fuel boiler with a pellet burner for a passive type house heating. During experimental researches samples of wood pellets, rapeseed pellets and beets pulp were used. On the received graphs the changes in the temperature state of the combustion chamber at the stage of pelletʼs ignition, burning and fading were reflected. It was found that the largest increase in temperature occurs near the wall of the boiler, which is opposite to the burner. As can be seen on the graphs, temperature fluctuations occur as a result of the periodic burning of biofuel in the burner and the arrival of a new portion of pellet from the hopper. As the experiments showed, the temperature level at burning of rapeseed pellets is much lower than in comparison with wood pellets, and to go to the established mode of burning of beet pulp pellets is generally problematic. It is obvious that when setting up the fuel supply system and modes of operation of the fuel it is necessary to take into account heat physical characteristics of fuel, first of all moisture and heat capacity, as well as yield of volatile combustible components. For this purpose, a gas analysis was carried out when burning wood pellets. The selection of combustion products was done in the wild immediately after the boiler. As a result, the NOx and CO concentrations of the appropriate temperature were obtained at the sample site. The nitrogen oxide concentrations should be considered moderate, which cannot be argued about the concentration of carbon monoxide, which requires further research. The obtained results can be used to increase the efficiency of combustion process at burning biofuel in boilers of low power communal and industrial heat power, social-budget sphere and individual-household sector.

Investigation of the cellulose-water relationship by the pressure plate method

The water retention properties of papermaking fibers have been investigated by a "pressure plate" technique which permits a measurement of equilibrium moisture contents of pulp samples at precisely controlled relative vapor pressures between 0.99 and 1.00. This range encompasses the water contents of interest in papermaking from the table to the middle of the drier section. Water retention isotherms are drawn and are satisfactorily related to desorption isotherms which have been reported in the literature. Isotherms for a variety of pulps are reported. These are related to the papermaking properties of the fibers and show the effects of wood species, cooking method, pulp yield, bleaching, drying, and beating on the cellulose-water relationship.

Sulfide Variation in the Coeur Rochester Silver Deposit: Use of Geologic Block Modeling in the Prediction and Management of Mine Waste

Abstract A critical issue in mine waste management is the management and mitigation of acid rock drainage and metal leaching particularly from waste rock. This requires good understanding and characterization of materials most likely to generate acid pH waters and generate leachable metals and metalloids, as well as the presence of minerals most likely to neutralize acidic pH such as carbonates and certain silicates. For low-sulfidation epithermal deposits in silica-rich volcanic rocks, neutralization minerals are rare. Consequently, determination of acid generation is almost entirely a function of sulfide content of the rocks. By understanding the distribution of sulfide minerals within such a deposit, an initial mine waste management plan can be developed. The Rochester mine currently exploits a low-sulfidation epithermal gold-silver deposit and is located on the southern flank of the Humboldt Range in west-central Nevada. The Rochester mine is a conventional open-pit mining operation with cyanide heap leaching and Merrill Crowe processing. Silver and lesser gold mineralization occur associated with sulfide minerals hosted in Permian-Triassic Koipato Group rhyolitic units with extensive quartz-sericite-pyrite alteration. Gangue mineralogy of the deposit is dominated by slow or unreactive silicate minerals with little or no carbonate. Silver-bearing mineralization was controlled by primary hypogene sulfides and secondary supergene oxidation processes, and most of the mineralized material mined to date has been fully or partially oxidized. Oxidation mobilizes and depletes all forms of sulfur from primary sulfide minerals. Due to the low sulfate content and low content of neutralizing gangue phases, the waste rock classification can be based on total sulfur content. Based on the analysis of pulp samples collected from within the mine area, a sulfur block model was developed and compared to the results of standard acid-base accounting and net acid generation tests. This comparison demonstrates the benefit of the block model in identifying zones of potentially acid-generating material in the mined waste. Application of this information to mine planning has allowed more efficient management of acid-generating mine waste by allowing the operator to develop areas of the waste rock facility to receive the waste in a timely fashion. Such an approach is based on good mine geologic and mineralogical characterization and the use of a representative and comprehensive geologic block model.

Optimization of Phenolic Compounds Extraction of Different Parts of Camu-camu Fruit from Different Geographic Regions.

Phenolic compounds in camu-camu (Myrciaria dubia) have received interest due to their health-promoting effects. However, these compounds have been poorly investigated in the different parts of the camu-camu fruit (pulp, peel, and seeds). This study aimed to optimize the solvent composition for extraction of phenolic compounds from pulp, peels, and seeds of camu-camu through a simplex-centroid mixture design. Then, the profile of phenolic compounds in samples of camu-camu pulp, peels, and seeds from different regions in Brazil and South America was determined by UPLC-ESI-MS/MS. Aqueous ethanol (80%, v/v) yielded the highest extraction for the pulp and peel, while aqueous methanol (50%, v/v) was selected for the seed. Camu-camu parts had p-coumaric acid, catechin, epicatechin, luteolin, rutin, and quercetin, with catechin as the major compound in the pulp, peels, and seeds of all the evaluated samples. The peel showed lower concentrations of these compounds compared with the pulp and the seed; the content of phenolic compounds also differed according to the geographic region. These results broaden the knowledge on phytochemical extraction and composition of camu-camu pulp, peel, and seed and may guide future applications of their extracts in the food industry.

Effects of aging and inflammation on catalase activity in human dental pulp

ObjectivesIn this study, it was aimed to examine the catalase activity in clinically healthy and caries-related inflamed symptomatic human dental pulps of young and old individuals. DesignSixty pulp samples from young and old healthy donors, were collected depending on pulpal status. 48 samples were used for spectrophotometric analysis and 12 samples for immunohistochemistry. Healthy pulps were maintained from non-carries, extracted third molars. Reversible and irreversible pulpitis samples were obtained by pulp extirpation during endodontic treatment. Following homogenization catalase enzyme activity was determined by spectrophotometry. Additionally, two pulp tissue samples from each group were fixed and evaluated for catalase immunoreactivity. ResultsCatalase enzyme activity in old healthy pulp samples were significantly higher than healthy young samples (p ≤ 0.05). Reversible and irreversible pulpitis samples indicated significantly decreased activity compared to healthy samples in elderly group (p ≤ 0.05). Young reversible pulpitis samples showed significantly increased catalase activity when compared to irreversible pulpitis and the reversible pulpitis samples in elderly group (p ≤ 0.05). Immunohistochemical evaluation indicated that there was intense catalase immunoreactivity in young patients with reversible pulpitis compared with reversible pulpitis in elderly group. However, weak immunoreactivity was observed in young irreversible pulpitis and elderly reversible pulpitis samples. ConclusionsThe pulp tissues presented different levels of catalase activities against pulpitis and aging.

Preliminary Characterization of Phytochemicals and Polysaccharides in Diverse Coffee Cascara Samples: Identification, Quantification and Discovery of Novel Compounds.

Coffee cascara is the first and most significant by-product of the coffee processing industry, whose valorization has become an urgent priority to reduce harmful environmental impacts. This work aimed to provide an improved understanding of phytochemicals and polysaccharides in coffee cascara in order to offer information for the better evaluation of potential applications. Phytochemicals in 20 different coffee cascara samples were ultrasonically extracted and analyzed by HPLC-UV and HPLC-MS/MS. Four novel compounds were isolated for the first time from coffee cascara, including two still unknown tautomers (337 Da), and two dihydroflavonol glycosides (dihydromyricetin glycoside and dihydromyricetin rhamnosylglycoside). Their presence can contribute to the design of new value-added applications of coffee cascara. Chemical characterization of two polysaccharides from two of the coffee cascara pulp samples showed that they were mainly composed of homogalacturonan, with rhamnose and arabinose as minor neutral sugars. In addition, principal component analysis results indicated that coffee cultivar and/or country significantly impacted the phytochemical composition of coffee cascara, although differences may be reduced by the external environment and processing method. It is suggested that processing method should be carefully designed when generating coffee cascara from the same cultivar and country/farm.

New approach for screening of microorganisms from Arabica coffee processing for their ability to improve Arabica coffee flavor.

The purpose of this research was to isolate microorganisms from coffee fermentation processes and screen them for their potential to improve the flavor of Arabica coffee using a new approach that included pectin degradation ability and growth in mucilage broth. All of the studied microorganisms were isolated from 38 different samples of fresh coffee cherries, coffee mucilage and coffee pulp. A total of 262 microbial isolates were obtained and subjected to screening using pectinase screening agar medium for pectinolytic organisms. The results of the pectinase production test showed that 18 yeast isolates were found to produce pectinase that could degrade the pectin present in solid media. The sugar assimilation profiles and growth of selected strains in mucilage broth were studied. Therefore, 18 isolates from the selected yeasts were subjected to molecular identification by the use of 18S rRNA gene sequencing. The diversity of the yeast isolates was studied, and they were identified as Wickerhamomyces anomalus, Naganishia liquefaciens, Pichia kudriavzevii, Kazachstania naganishii and Kazachstania sp. Moreover, isolates SWU3YWP1-3, SWU3YSK9 and INFCY1-4 were used as a seed culture for Arabica coffee fermentation. The cupping sensory scores of the control (without yeast inoculation) and those inoculated with three isolated yeast strains that were determined by Q-Arabica Graders were 73.75, 84.75, 80.25 and 75.00, respectively. Unique flavors and aromas were detected. This is the first report of screening microorganisms from the Arabica coffee fermentation process by the combination of various properties with success in improving the quality of coffee beverage.

Evaluation of the effects of transition metal ions on the optical aging and whiteness of chemimechanical pulp

The negative effects of metal ions were addressed relative to the whiteness characteristic of chemomechanical pulp samples prepared. Proper solutions were considered to mitigate this adverse effect. The chemomechanical pulp samples were supplied in an unbleached form. The samples were wetted using ethylene diamine tetra acetic acid (EDTA) chelating agent, and then each of the samples was wetted with EDTA after drying with solutions containing the transitional metal ions. The results showed that the greatest whiteness reduction resulted from Fe2+ ions, whereas the smallest effect resulted from Al3+ ions. Wetting of the samples in various concentrations of the chelating agent (EDTA) had an optimum value in improving the whiteness characteristic of the paper. Thereafter, no change was created in whiteness improvement and brightness stability by increasing the concentration of EDTA. Increasing the aging time reduced the whiteness characteristic of the chemomechanical pulp.

Effectiveness of biomass-based fly ash in pulp and paper liquid waste treatment

Adsorption is regarded as one of the most promising and straightforward strategies for reducing organic pollutants from wastewater effluents. The use of adsorbents from economical raw materials, even those from waste, is one recent concern. This study aims to test the effectiveness of biomass-based fly ash in treating liquid waste from pulp and paper production activities. Fly ash (FA) performance for adsorption was tested by varying the ratio of adsorbent with wastewater by 20, 40, 60, and 80 g/L. The adsorbents' performance was then compared between the application of FA directly (without activation) and adsorbents that were previously calcinated in 100 °C and 200 °C. Samples of pulp and paper liquid waste are placed on the erlenmeyer flask and stirred using a jar test with speeds varying by 100, 200, and 300 rpm. The results showed that FA is potential directly used with no thermal treatment as an adsorbent in treating liquid waste in the pulp and paper industry. It was effectively used with a dosage of 20 g/L and a 100 rpm fatigue speed with a contact time of 10 min. The quality changes of several wastewater parameters were found with a 92.5% reduction in TSS, 83.31% in COD, 19.99% in chlorides, 95.41% in NH3, and 19.6% in TDS, 19.6% in EC. Those parameters have successfully complied with the regulation standard of Indonesia (SNI) for wastewater.

Comparative metabolomics reveal intraspecies variability in bioactive compounds of different cultivars of pomegranate fruit (Punica granatum L.) and their waste by-products.

The different parts of pomegranate fruit are considered a powerful mixture of bioactive compounds yet the peels and pulps of the fruits are usually discarded and considered as industrial waste. In this work, ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-QqQ-MS) was utilized for metabolomics analysis of different parts (peel, pulp, seed and juice) of pomegranate fruit cultivars to verify possible variations among the fruits and their waste products as potential sources of functional constituents. Orthogonal projection to latent structure-discriminant analysis (OPLS-DA) coefficient-plot showed enrichment of phenolic compounds such as punicalagin and ellagic acid derivatives in pulp samples while seeds class was enriched in phlorizin, catechin and quercetin, juice class showed abundance of naringenin and pelargonidin-3-pentoside while peels were enriched in anthocyanins and flavonoids including cyanidin diglycoside, quercetin and luteolin glycosides. Although the juice samples of almost all tested cultivars showed remarkable cytotoxic activity, the pulp samples, particularly the Manfalouti cultivar, exhibited the most potent [half maximal inhibitory concentration (IC50 )= 2.367 ± 0.14 μg/mL in MCF-7, IC50 = 3.854 ± 0.23 μg/mL in Hep-G2 cell lines]. OPLS models were constructed for determination of cytotoxicity-associated metabolites among where the coefficients plots revealed tannins; granatin A, ellagic acid derivatives, punicalagin α and β, in addition to anthocyanins and phenolic compounds; cyanidin diglycoside, quercetin, phlorizin, 3-O-caffeoylquinic acid, naringenin and liquiritin were more pertinent with cytotoxicity of the different parts of pomegranate fruit. The results obtained allow for the full utilization of the resources of pomegranate fruit and its industrial waste as sources of bioactive compounds. © 2022 Society of Chemical Industry.

Expression of PAR2 and NF-κB in human primary dental pulp odontoblasts during the progression of caries

Increased proteinase-activated receptor-2 (PAR2) expression is observed in various diseases related to inflammation. However, the expression of PAR2 in odontoblasts in response to dental caries has not been investigated. Therefore, to explore the functions of odontoblasts during the progression of carious infection, we measured PAR2 and NF-κB expression using immunofluorescence techniques in the odontoblast layer and pulpocytes in the sub-odontoblast region of 44 teeth extracted from children undergoing dental treatment (eight sound samples, 13 early carious samples, 16 advanced carious samples, and eight exposed pulp samples). PAR2 and NF-κB were expressed at moderate levels in sound teeth with non-carious pulp, and the expression levels changed as caries progressed. PAR2 was significantly upregulated in the odontoblast layer during early-stage and advanced-stage caries, and reduced below healthy levels in teeth with exposed pulp. NF-κB was significantly upregulated in early-stage caries and significantly downregulated in advanced-stage and late-stage caries. Moreover, in the sub-odontoblast region, NF-κB expression increased with the progression of caries. Overall, this study suggests PAR2 may represent a crucial cell signalling receptor in the dentine-pulp complex during dental inflammation, and that NF-κB may be one of the key pathways that regulate inflammatory immune responses in the dental pulp.

Modeling pesticide translocation injected by endotherapy into the stem of coconut tree (Cocos nucifera L.)

Aim of study: To present a mathematical model to simulate the translocation of pesticides injected into coconut trees. Pesticide residues in water and coconut pulp were also evaluated. Area of study: The data were obtained in coconut plants of the Itaporanga Experimental Field, located in the Municipality of Itaporanga d'Ajuda, Sergipe State, Brazil. Material and methods: To estimate the effect of pesticide site-sap coefficients and retardation factors on translocation and its phytosanitary behavior and risk of contamination of coconut fruits, the stipe was modeled by a classic dispersion-advection equation. The pesticides cyproconazole, azoxystrobin, dimethoate, imidacloprid, metalaxyl, and thiamethoxam were injected into the coconut palm stipe. The method used to extract pesticide residues from pulp, water and coconut sap samples was based on the QuEChERS methodology with modifications. Main results: Simulations showed that (i) the pesticides dimethoate, metalaxyl, and thiamethoxan were the active ingredients showing the greatest potential for translocation in the sap of the coconut tree stem; (ii) the pesticides imidacloprid and metalaxyl translocated upward in the stipe, and more rapidly than pesticides abamectin and cyproconazole, which moved slower to the aerial part of coconut plants. In chromatography analysis, no pesticide residues were quantified in water and coconut fruit pulp samples of coconut trees injected with pesticides, after the evaluated intervals. Research highlights: The proposed model allowed us to observe that the translocation is inversely proportional to the sorption of the pesticide in the stem of coconut trees.

Front-Face Fluorescence Spectroscopy and Feature Selection for Fruit Classification Based on N-CovSel Method

Internal disorder is a major problem in fruit production and is responsible for considerable economical losses. Symptoms are not externally visible, making it difficult to assess the problem. In recent years, 3D fluorescence spectroscopy has been used to reveal features of interest in agronomical field, such as plant stress and plant infection. Such technique could provide useful information regarding changes that occur at the tissue level, in order to distinguish spectral differences between healthy and disordered fruits. This paper introduces the use of the new three-way feature extraction N-CovSel method, compared to the commonly used N-PLS-DA method. These approaches were used upon front-face fluorescence spectra of 27 fruit pulp and skin samples, by analysing excitation wavelengths ranging from 250 to 650 nm, and emission wavelengths varying from 290 to 800 nm. N-CovSel method was applied to identify the most relevant features on: 1) excitation-emission wavelength couples, 2) excitation wavelengths whatever the emission wavelengths and 3) emission wavelengths whatever the excitation wavelengths. Discriminant analysis of the selected features were performed across classes. The constructed models provided key features to differentiate healthy fruits from disordered ones. These results highlighted the capability of N-CovSel method to extract the most fitted features for enhanced fruit classification using front-face fluorescence spectroscopy. They revealed characteristic fluorophores involved in the structural modifications generated by the physiological disorder studied. This paper provides preliminary results concerning the suitability of N-CovSel method for the desired application. Further investigations could be performed on intact fresh fruits in a non-destructive way, allowing an earlier and faster detection of the internal disorder for in-field or industrial applications.

Effect of altitude on polysaccharide and lignin contents of brutian pine (Pinus brutia Ten.) wood and kraft pulp

This study investigated the chemical properties of Brutian pine (Pinus brutia Ten.) wood samples collected at altitudes of 800 m, 900 m, and 1000 m and the behaviors of the chemical components of the same materials during kraft pulping. Chemical component analysis indicated that the wood and pulp sample from 1000 m contained higher quantities of holocellulose and α-cellulose, and a lower quantity of lignin. For both wood and pulp samples, a continuous increase in holocellulose and α-cellulose contents and a continuous decrease in lignin content were observed with increasing altitude. Gas chromatography analysis of monosaccharides determined that the highest cellulose and hemicellulose contents were obtained from the wood and pulp sample from 1000 m. Quantity of these components increased with increasing altitude. Lastly, kraft pulping degraded 14.10-15.70% of cellulose, 56.49-61.35% of galactoglucomannan, 65.75-69.61% of arabinoglucoronoxylan, and 92.42-93.48% of lignin in the samples.

Nutritional, Physicochemical and Structural Parameters of Mauritia flexuosa Fruits and By-Products for Biotechnological Exploration of Sustainable Goods.

SUMMARYResearch backgroundCommercialization of Mauritia flexuosa (buriti) fruits in Brazil is at an early stage. Herein, we evaluate the nutritional value of pulp, peel and endocarp samples from buriti fruits, perform macroscopic and microscopic evaluations and analyze their physicochemical properties.Experimental approachSize and mass, pH, sugar and protein contents, soluble/insoluble fiber, total titratable acidity and energy value of the samples were analyzed. Mineral profiling was performed by energy dispersive X-ray fluorescence spectrometry, and fatty acids and phytosterols were determined by gas chromatography-mass spectrometry. Samples were also submitted to differential scanning calorimetry coupled to a thermal analyzer, and microstructure, morphology, surface and viscosity were evaluated by scanning electron microscopy (SEM) and X-ray diffraction (XRD) with copper radiation. Rheological behavior was also studied.Results and conclusionsLyophilized pulp had higher nutritional content of minerals, proteins, carbohydrates and energy than in natura pulp. Lyophilized pulp and its by-products showed suitable yields (>17.31%) and low aw, and potassium, manganese and monounsaturated fatty acid contents. Peels showed elevated amounts of saturated and polyunsaturated fatty acids and phytosterols (β-sitosterol and stigmasterol), and endothermic behavior. The reductions of calcium, magnesium and manganese ranging from 18.5 to 22.7% were observed following the lyophilization. Drying processes generated semi-crystalline powders. Both peels and endocarp contained higher amounts of insoluble fiber and lower contents of sugars. Similar results were obtained by microscopic morphological analysis, differential scanning calorimetry and XRD analysis. Pulp and endocarp exhibited pseudoplastic non-Newtonian behavior, and flow behavior index values were lower than 1, while peels presented dilatant behaviour. Thus, physicochemical and nutritional characterization of pulp and by-products, such as peels and endocarp, are essential to support scientific research and exploration of new sustainable products.Novelty and scientific contributionProcessing and conservation techniques, like lyophilization, maintain the good quality of nutritional contents and bioactive compounds of buriti whole fruits, and can be used to extend their shelf life, preserve alimentary characteristics and provide wider purposes and availability. Such parameters may generate income and food security for local and regional communities.

Does α-lipoic acid therapeutically effective against experimentally induced-acute pulpitis in rats?

The purpose of the study was to investigate the therapeutic effects of α-lipoic acid (ALA) on an induced-acute pulpitis model in rats. Twenty-four Wistar albino rats were randomly divided into three groups: control, induced-acute pulpitis (PULP) and PULP+ALA groups. In the PULP and PULP+ALA groups, the crowns of the maxillary left incisors were removed horizontally. All exposed pulp tissues were treated with 5µL LPS solution. In the PULP+ALA group, the rats were treated intraperitoneally with a single dose of ALA (100mg/kg). The rats were sacrificed 24h after pulp injury, and the trunk blood and pulp samples were collected and then determined using ELISA assay kits. TNF-α, IL-1β, MMP-1 and MMP-2levels in the serum and pulp tissues were considerably higher in the PULP group than the control group (p<0.01-0.001). In the PULP+ALA group, TNF-α, IL-1β, MMP-1 and MMP-2levels in the serum and pulp tissues decreased significantly compared to the PULP group (p<0.05-0.001). ALA decreases pro-inflammatory mediators and proteolytic enzymes, which might relieve acute inflammation.

ENVIRONMENTALLY FRIENDLY BLEACHING OF DISSOLVING CHEMICAL SULPHITE WOOD PULP AND CHARACTERIZATION OF WASTE WATER

The aim of the work is the environmental assessment for bleaching and alkali treatment of dissolving chemical pulp. Samples of the original unbleached pulp: industrial hard bisulfite pulp with a high mass fraction of lignin, traditionally used for the production of paper, and soft sulfite pulp with a low content of lignin, usually used to produce dissolving chemical pulp. In order to reduce the environmental impact, bleaching and alkali treatment were carried out according to the original technologies developed by the authors: bisulfite pulp - according to the ECF technology using two oxidizing bleaching reagents by scheme Pa-E-Ch1-HE-Ch2-A; sulfite pulp - according to the TCF-technology using one oxidizing bleaching agent by scheme Pa-E-HE-P-A in just 4 stages. Produced samples of pulp according to the standardized quality indicators, meet the requirements of the norms for wood sulphite pulp CA grade P (for nitration). The environmental characteristics of wastewater from bleaching and alkali treatment of both samples using the developed ECF and TCF technologies after biological treatment in terms of the main indicators (COD, BOD, AOX) comply with EU standards.

ECO-FRIENDLY PULPING OF BANANA PSEUDO-STEM WASTES WITH POTASSIUM-BASED PROCESSES

This study aimed to investigate the usability of banana pseudo-stem wastes, remaining from banana cultivation, with eco-friendly K-based pulping processes. Three different K-based pulping processes, KOH, KOH-K2SO3, KOH-NH4OH, and soda process as control were studied. The temperature and the total alkali ratio were kept constant, while the cooking time was varied (60 min and 120 min) for each K-based pulping method. It was found that 60 min at 165 °C with 20% alkaline charge (calculated as Na2O) are the optimum conditions for all K-based pulping processes of banana pseudo-stems. K-based pulps produced under the same pulping conditions were compared with the control soda pulp. The pulp samples were characterized in terms of their mechanical, physical, morphological and optical properties. Also, their Fourier-transform infrared spectroscopy analysis was performed. Among the eco-friendly K-based pulping processes investigated here, the KOH process can be considered as a promising alternative for pulping banana pseudo-stem waste, due to the excellent papermaking properties achieved.