Search Results (23)

Xylanase is an essential industrial enzyme for degrading plant biomass, pulp and paper, textiles, bio-scouring, food, animal feed, biorefinery, chemicals, and pharmaceutical industries. Despite its significant industrial importance, the extensive application of xylanase is hampered by high production costs and concerns regarding the safety of xylanase-producing microorganisms. The utilisation of renewable polymers for enzyme production is becoming a cost-effective alternative. Among the prospective candidates, non-pathogenic lactic acid bacteria (LAB) are promising for safe and eco-friendly applications. Our investigation revealed that Pediococcus pentosaceus G4, isolated from plant sources, is a notable producer of extracellular xylanase. Improving the production of extracellular xylanase is crucial for viable industrial applications. Therefore, the current study investigated the impact of various medium components and optimised the selected medium composition for extracellular xylanase production of P. pentosaceus G4 using Plackett–Burman Design (PBD) and Central Composite Design (CCD) statistical approaches. According to BPD analysis, 8 out of the 19 investigated factors (glucose, almond shell, peanut shell, walnut shell, malt extract, xylan, urea, and magnesium sulphate) demonstrated significant positive effects on extracellular xylanase production of P. pentosaceus G4. Among them, glucose, almond shells, peanut shells, urea, and magnesium sulphate were identified as the main medium components that significantly (p < 0.05) influenced the production of extracellular xylanase of P. pentosaceus G4. The optimal concentrations of glucose, almond shells, peanut shells, urea, and magnesium sulphate, as determined via CCD, were 26.87 g/L, 16 g/L, 30 g/L, 2.85 g/L, and 0.10 g/L, respectively. The optimised concentrations resulted in extracellular xylanase activity of 2.765 U/mg, which was similar to the predicted extracellular xylanase activity of 2.737 U/mg. The CCD-optimised medium yielded a 3.13-fold enhancement in specific extracellular xylanase activity and a 7.99-fold decrease in production costs compared to the commercial de Man, Rogosa and Sharpe medium, implying that the CCD-optimised medium is a cost-effective medium for extracellular xylanase production of P. pentosaceus G4. Moreover, this study demonstrated a positive correlation between extracellular xylanase production, growth, lactic acid production and the amount of sugar utilised, implying the multifaceted interactions of the physiological variables affecting extracellular xylanase production in P. pentosaceus G4. In conclusion, statistical methods are effective in rapidly assessing and optimising the medium composition to enhance extracellular xylanase production of P. pentosaceus G4. Furthermore, the findings of this study highlighted the potential of using LAB as a cost-effective producer of extracellular xylanase enzymes using optimised renewable polymers, offering insights into the future use of LAB in producing hemicellulolytic enzymes. Full article

Opuntia stricta var. dillenii extracts exhibit anti-oxidative and anti-inflammatory properties, which are of significant interest for the prevention and management of metabolic dysfunction-associated fatty liver disease (MAFLD). The present study is the first to investigate the potential anti-steatotic effect of Opuntia stricta var. dillenii extracts. The aim is to evaluate the anti-steatotic effect of extracts from various parts of the plant (whole fruit, peel, pulp, and the industrial by-product, bagasse) in an in vitro model using both murine AML12 and human HepG2 hepatocytes. Results have demonstrated that all tested extracts, including those from the whole fruit, peel, pulp, and bagasse, exert an anti-steatotic effect. In murine hepatocytes, the whole fruit extract at 100 μg/mL and the peel extract at 10 μg/mL presented the highest capacity to reduce PA-induced triglyceride accumulation. In fact, the peel was the most potent extract, preventing lipid accumulation at the lowest dose used. In human HepG2 hepatocytes, the peel, pulp, and bagasse extracts at 100 μg/mL demonstrated the greatest triglyceride reduction, suggesting that the human model is less responsive. Regarding the main mechanism of action, the peel and pulp extracts seem to inhibit de novo lipogenesis. Additionally, the downregulation of the fatty acid transporter CD36 appears to contribute to the prevention of triglyceride accumulation in both extracts. Full article

The size and appearance of loquats are crucial for their acceptance in the consumer market. The loquat tree has intense fruiting, which suggests thinning flower buds in order to improve the quality of loquat fruit production. This study was performed in the Paraíba Valley region of the state of São Paulo, in the subtropical region of southeastern Brazil to assess intensities of flower thinning at full bloom on the yield and fruit quality of loquat trees. The study was carried out over two consecutive harvest seasons. Trees of the cultivar ‘Precoce de Itaquera’ were used in a randomized block design with five intensities of hand thinning of the flower buds (4, 6, 8, 10, and 12 buds per cluster), with seven replicates. For all treatments, the clusters were bagged as soon as they were thinned. After harvesting, the number of fruit sets, cluster and fruit mass, yield, longitudinal and transverse lengths, number and mass of seeds, soluble solids content, titratable acidity, ripeness index, and pH of the fruit pulp were assessed. An overall improvement was achieved by maintaining four flower buds per cluster. This intensity of thinning provides greater fruit setting on the cluster, as well as larger and sweeter fruit. The highest cluster weight and yield were obtained by maintaining 12 flower buds per cluster. Full article

Background: The study exploited, for the first time, Attenuated Total Reflectance-Fourier Transform-InfraRed (ATR-FTIR) spectroscopy on human dental pulps at different timings of root resorption (RR) to deepen the biological mechanisms occurring in deciduous teeth (De) during their replacement with permanent ones. Methods: N:36 dental pulps from sound De were divided into the following: G0 (no RR); G1 (RR less than 1/3 of root length); G2 (RR not exceeding 2/3 of root length); and G3 (RR more than 2/3 of root length). Samples were analyzed by ATR-FTIR, and the spectral data were submitted to univariate (One-way ANOVA and Tukey’s multiple comparison tests; statistical significance set at p < 0.05) and multivariate (Principal Component Analysis, PCA) analyses. Results: PCA displayed good discrimination among groups, ascribable to: (i) the intensity of the peaks of nucleic acids (~1715 cm⁻¹, ~1237 cm⁻¹, ~964 cm⁻¹, and ~815 cm⁻¹) and carbohydrates (~1159 cm⁻¹) which increased from G0 to G3 (p < 0.05); (ii) the relative amount of lipids which decreased from G0 to G3 (p < 0.05); and (iii) the intensity of the peaks at ~1014 cm⁻¹, and ~875 cm⁻¹ (phosphates and carbonates in hydroxyapatite), which decreased from G0 to G3 (p < 0.05). Conclusions: This study confirmed ATR-FTIR as a reliable and quick technique for the characterization of the dental pulp and highlighted a correlation between specific molecular changes in the dental pulp of deciduous teeth and different RR stages, shedding new light on this process and paving the way for future research, which could improve the clinical management of the primary dentition. Full article

Cellulose nanocrystals (CNC) receive great attention for their physical and optical properties, high surface area, high tensile strength, rigidity (Young’s modulus up to 140 GPa), and ease of surface modification. However, controlling the properties of CNC is still challenging, given the wide variety of pulp sources and the complexity of finding suitable processing conditions. In the present study, acid hydrolysis efficiently isolated CNC from wood Acacia mearnsii brown kraft pulp (AMKP). Initially, the AMKP was delignified by the treatment with acidified sodium chlorite. The Acacia mearnsii kraft pulp obtained was then subjected to acid hydrolysis with sulfuric acid at concentrations of 50 to 58% 45 °C for 60 min. The hydrolysate was sonicated in an ultrasonic processor for 30 min. The chemical composition was determined by Fourier transform infrared spectroscopy (FTIR), crystallinity by X-ray diffraction (XRD), zeta potential by Zetasizer ZS equipment, thermal stability by thermogravimetric analysis (TGA), and morphology by transmission electron microscopy (TEM) to verify the effect of acid concentration on the yield and properties of CNC. The optimization of the isolation process demonstrated that the maximum yield of 41.95% can be obtained when AMWP was hydrolyzed with sulfuric acid at a concentration of 54%. It was possible to isolate CNC with a crystallinity index between 71.66% and 81.76%, with the onset of thermal degradation at 240 °C; zeta potential of −47.87 to 57.23 mV; and rod-like morphology, with lengths and widths between 181.70 nm and 260.24 nm and 10.36 nm and 11.06 nm, respectively. Sulfuric acid concentration significantly affected the yield of acid hydrolysis, allowing the isolation of CNC with variable dimensions, high thermal stability, high crystallinity index, and great colloidal stability in aqueous medium. Full article

Lignin, the second most abundant natural polymer, is a by-product of the biorefinery and pulp and paper industries. This study was undertaken to evaluate the properties and estimate the prospects of using lignin as a by-product of the pretreatment of common reed straw (Phragmites australis) with deep eutectic solvents (DESs) of various compositions: choline chloride/oxalic acid (ChCl/OA), choline chloride/lactic acid (ChCl/LA), and choline chloride/monoethanol amine (ChCl/EA). The lignin samples, hereinafter referred to as Lig-OA, Lig-LA, and Lig-EA, were obtained as by-products after optimizing the conditions of reed straw pretreatment with DESs in order to improve the efficiency of subsequent enzymatic hydrolysis. The lignin was studied using gel penetration chromatography, UV-vis, ATR-FTIR, and ¹H and ¹³C NMR spectroscopy; its antioxidant activity was assessed, and the UV-shielding properties of lignin/polyvinyl alcohol composite films were estimated. The DES composition had a significant impact on the structure and properties of the extracted lignin. The lignin’s ability to scavenge ABTS^+• and DPPH^• radicals, as well as the efficiency of UV radiation shielding, decreased as follows: Lig-OA > Lig-LA > Lig-EA. The PVA/Lig-OA and PVA/Lig-LA films with a lignin content of 4% of the weight of PVA block UV radiation in the UVA range by 96% and 87%, respectively, and completely block UV radiation in the UVB range. Full article

Cocoa tree plantations aim to harvest grains found in the cob to produce cocoa and chocolate. There has been a growing interest in valorizing the secondary components of the cocoa fruit, such as the peel, placenta, and mucilage/pulp, as valuable sources of nutrients for healthy food preparation. In other words, by-products derived from these raw materials are an exploitable source of nutrients in the preparation of healthy food. In the present study, two varieties of cocoa, National Cocoa Fino de Aroma (NCFA) and Colección Castro Naranjal 51 (CCN-51), were evaluated and harvested during both dry and rainy seasons. This evaluation was based on the profiling of the cob, peel, grain, placenta, and mucilage in different stages of ripeness (underripe, ripe, and overripe). Also, from the ripe raw material, a fermented beverage prototype was developed, such as kombucha, with different concentrations of mucilage (40, 60, 80, and 100 g/L). Physicochemical analyses, such as acidity, °Brix, pH, moisture, ash, protein, fat, fiber, vitamins, sugars, and polyphenols of the raw mucilage material and acidity, °Brix, and pH values of the fermented kombucha, were carried out. The best performances were obtained with the CCN-51 variety in the rainy season. Among the fermented drink panelists, the CN40 treatment (Nacional Mucilage + 40 g/L of sugar) received the highest acceptability and was considered the best. Given its efficiency, nutritional content, and potential applications, this product presents a promising strategy to address Sustainable Development Goals related to zero hunger, health and well-being, and climate action. Full article

Opuntia stricta var. dillenii fruit is a source of phytochemicals, such as betalains and phenolic compounds, which may play essential roles in health promotion. The aim of this research was to study the triglyceride-lowering effect of green extracts, obtained from Opuntia stricta var. dillenii fruit (whole fruit, pulp, peel, and industrial by-products (bagasse)) in 3T3-L1 mature adipocytes. The cells were treated on day 12, for 24 h, after the induction of differentiation with the extracts, at doses of 10, 25, 50, or 100 μg/mL. The expression of genes (PCR-RT) and proteins (Western blot) involved in fatty acid synthesis, fatty acid uptake, triglyceride assembly, and triglyceride mobilisation was determined. The fruit pulp extraction yielded the highest levels of betalains, whereas the peel displayed the greatest concentration of phenolic compounds. The extracts from whole fruit, peel and pulp were effective in reducing triglyceride accumulation at doses of 50 μg/mL or higher. Bagasse did not show this effect. The main mechanisms of action underpinning this outcome encompass a reduction in fatty acids synthesis (de novo lipogenesis), thus limiting their availability for triglyceride formation, alongside an increase in triglyceride mobilisation. However, their reliance is contingent upon the specific Opuntia extract. Full article

In this study, we address the ecological challenges posed by automotive battery recycling, a process notorious for its environmental impact due to the buildup of hazardous waste like foundry slag. We propose a relatively cheap and safe solution for lead removal and recovery from samples of this type of slag. The analysis of TCLP extracts revealed non-compliance with international regulations, showing lead concentrations of up to 5.4% primarily in the form of anglesite (PbSO₄), as detected by XRF/XRD. We employed deep eutectic solvents (DES) as leaching agents known for their biodegradability and safety in hydrometallurgical processing. Five operational variables were systematically evaluated: sample type, solvent, concentration, temperature, and time. Using a solvent composed of choline chloride and glycerin in a 2:1 molar ratio, we achieved 95% lead dissolution from acidic samples at 90 °C, with agitation at 470 rpm, a pulp concentration of 5%, and a 5 h duration. Furthermore, we successfully recovered 55% of the lead in an optimized solution using an electrowinning cell. This research demonstrates the ability of DES to decontaminate slag, enabling compliance with regulations, the recovery of valuable metals, and new possibilities for the remaining material. Full article

Fermentation is a critical step in the production of coffee when following standard wet processing, one of the most common methods used to remove the mucilage layer from coffee cherries. During this step, the de-pulped coffee cherries undergo fermentation with native yeast that modifies the flavor profile of the resultant coffee. This study aimed to ferment green coffee beans using commercial yeast strains from beer and wine prized for their ability to produce specific flavors, and subsequently evaluate the aroma and flavor of the coffee using coffee consumers. Four Saccharomyces cerevisiae strains were used: Belgian Ale, Sourvisiae, 71 B, and Tropical IPA, along with one non-Saccharomyces, Toluraspora delbrueckii (Biodiva), and a non-inoculated control sample. The green coffee beans underwent a controlled wet fermentation for 72 h, followed by roasting, grinding, and brewing. Results showed that flavor profiles varied broadly by yeast strain, suggesting that producing novel flavors in coffee through fermentation is feasible and that these flavors survive the roasting process; however, higher liking scores were still reported for the control sample compared to the fermented samples. Biodiva, a strain used in wine to produce esters and fruity flavors, resulted in coffee with highly fruity notes, and all strains were rated more floral than the control, while the sample fermented with Sourvisiae yeast used in the brewing of sour ales resulted in coffee that was both perceived as more sour and had the lowest pH, likely due to the degree of lactic acid this strain is engineered to produce. Further, there were significant color differences between the samples. In conclusion, fermenting green coffee beans with brewing and winemaking yeast strains strongly impacted the flavor and aroma of the resultant coffee; however, evaluating larger panels of strains or optimizing strain performance may yield flavor profiles more suitable for coffee. Full article

Grasses are potential candidate to replace wood as a raw material for pulping and paper making, and several processes have been developed to produce grass pulp. In this study, wheat straw was used as raw material, and the possibility of sequential treatment with a mechanical method and deep eutectic solvent (DES) to prepare high-quality dissolving pulp was explored. Firstly, the wheat straw was mechanically treated, and then the wheat straw was delignified using a choline chloride–lactic acid deep eutectic solvent. The results showed that the optimal treatment conditions of deep eutectic solvent were 110 °C, 6 h, and a solid–liquid ratio (ratio of pulp to DES) of 1:40. The removal rate of lignin was 82.92%, the glucose content of pulp was increased by 11.42%. The DES recovery rate was further calculated, and the results showed that the DES recovery rate was more than 50% with rotary evaporation. The pulp viscosity after bleaching was 472 mL/g, and the α-cellulose accounted for 81.79%. This treatment has advantages in biomass refining, and the total utilization rate of wheat straw reaches 72%. This study confirmed that combined mechanical and deep eutectic solvent treatment can effectively remove lignin from wheat straw to produce high-quality wheat straw dissolving pulp. Full article

Worldwide, fruit processing industries reject high volumes of fruit waste, which represent rich sources of phenolic compounds and can be valorised through extraction, and then be reused for food, nutraceutical or cosmetic applications. In the present work, the optimisation of the recovery of phenolic compounds from apricot kernels and pulp, as well as peach pulp, through the green method of ultrasound and microwave assisted extraction (UMAE) is performed. Prior to extraction, a drying step of the pulps is conducted using freeze, vacuum and hot air drying. Except for the conventional extraction solvents of water and ethanol:water, a deep eutectic solvent (DES) formed by choline chloride/urea, and a natural deep eutectic solvent (NaDES) from choline chloride with lactic acid, are used, something that presentsecological benefits. With the aim of discovering the optimum extraction conditions, different values of the parameters of extraction time, utrasonic power and solvent/dry solid ratio are examined, and a mathematical model is developed to correlate them to the extraction yield (EY). The phenolic compounds and the antioxidant activity are determined through UV-Vis spectroscopy and High-Performance Liquid Chromatography (HPLC). The results of the study demonstrated that the most effective solvent in the extraction of apricot kernels is ethanol: water; DES is more efficient in the extraction of apricot pulp and NaDES in the extraction of peach pulps, reaching EYs of 25.65, 26.83 and 17.13%, respectively. In conclusion, both types of fruit waste are proved to have a significant content of valuable compounds, and the use of DES in fruit by-product extraction is effective and seems to be a promising alternative. Thus, the unexploited amounts of waste can be valorised through simple techniques and innovative solvents. Full article

Synsepalum dulcificum (Richardella dulcifica) is a berry fruit from West Africa with the ability to convert the sour taste into a sweet taste, and for this reason, the fruit is also known as the “miracle berry” (MB). The red and bright berry is rich in terpenoids. The fruit’s pulp and skin contain mainly phenolic compounds and flavonoids, which correlate with their antioxidant activity. Different polar extracts have been described to inhibit cell proliferation and transformation of cancer cell lines in vitro. In addition, MB has been shown to ameliorate insulin resistance in a preclinical model of diabetes induced by a chow diet enriched in fructose. Herein, we have compared the biological activities of three supercritical extracts obtained from the seed—a subproduct of the fruit—and one supercritical extract obtained from the pulp and the skin of MB. The four extracts have been characterized in terms of total polyphenols content. Moreover, the antioxidant, anti-inflammatory, hypo-lipidemic, and inhibition of colorectal cancer cell bioenergetics have been compared. Non-polar supercritical extracts from the seed are the ones with the highest effects on the inhibition of bioenergetic of colorectal (CRC) cancer cells. At the molecular level, the effects on cell bioenergetics seems to be related to the inhibition of main drivers of the de novo lipogenesis, such as the sterol regulatory element binding transcription factor (SREBF1) and downstream molecular targets fatty acid synthase (FASN) and stearoyl coenzyme desaturase 1 (SCD1). As metabolic reprograming is considered as one of the hallmarks of cancer, natural extracts from plants may provide complementary approaches in the treatment of cancer. Herein, for the first time, supercritical extracts from MB have been obtained, where the seed, a by-product of the fruit, seems to be rich in antitumor bioactive compounds. Based on these results, supercritical extracts from the seed merit further research to be proposed as co-adjuvants in the treatment of cancer. Full article

Increasing demand for lithium-ion batteries has led to the development of several new lithium mineral projects around the globe. Some major mineral processing challenges these projects face are similarities in gangue and value mineral behaviour and poor selectivity in froth flotation. Unsaturated anionic fatty acids are the primary spodumene flotation collectors, known to be strong collectors with poor solubility and selectivity. Fundamental flotation research consensus is that spodumene flotation is driven by a fatty acid–anion complex adsorbed at cationic aluminum sites. However, many small-scale studies result in poor recoveries, prompting several researchers to investigate cationic activators or mixed anionic/cationic collectors to improve flotation performance. Testwork with real spodumene ore is rare in recent literature, but older publications from several deposits prove that fatty acids can successfully concentrate spodumene. The process generally includes alkaline scrubbing, high-density fatty acid conditioning, and flotation at pH 7.5–8.5 with 500–750 g/t fatty acid collector. The collector speciation behaviour is notably sensitive to pulp conditions around this pH; possibly resulting in unstable flotation circuits and inconsistent results. This paper reviews fatty acid collector properties and the available industrial and fundamental spodumene flotation research. We aim to provide new insight for understanding particle-collector interactions in spodumene flotation and help bridge the gap between fundamental and industrial processes which will be needed to de-risk projects in the growing lithium mineral industry. Full article

Trapa bispinosa Roxb. is an economical crop for medicine and food. Its roots, stems, leaves, and pulp have medicinal applications, and its shell is rich in active ingredients and is considered to have a high medicinal value. One of the main functional components of the Trapa bispinosa Roxb. shell is 1-galloyl-beta-D-glucose (βG), which can be used in medical treatment and is also an essential substrate for synthesizing the anticancer drug beta-penta-o-Galloyl-glucosen (PGG). Furthermore, gallate 1-beta-glucosyltransferase (EC 2.4.1.136) has been found to catalyze gallic acid (GA) and uridine diphosphate glucose (UDPG) to synthesize βG. In our previous study, significant differences in βG content were observed in different tissues of Trapa bispinosa Roxb. In this study, Trapa bispinosa Roxb. was used to clone 1500 bp of the UGGT gene, which was named TbUGGT, to encode 499 amino acids. According to the specificity of the endogenous expression of foreign genes in Escherichia coli, the adaptation codon of the cloned original genes was optimized for improved expression. Bioinformatic and phylogenetic tree analyses revealed the high homology of TbUGGT with squalene synthases from other plants. The TbUGGT gene was constructed into a PET-28a expression vector and then transferred into Escherichia coli Transsetta (DE3) for expression. The recombinant protein had a molecular weight of 55 kDa and was detected using SDS-PAGE. The proteins were purified using multiple fermentation cultures to simulate the intracellular environment, and a substrate was added for in vitro reaction. After the enzymatic reaction, the levels of βG in the product were analyzed using HPLC and LC-MS, indicating the catalytic activity of TbUGGT. The cloning and functional analysis of TbUGGT may lay the foundation for further study on the complete synthesis of βG in E. coli. Full article