Conventional Hot Water Extraction Research Articles

Multiple fingerprinting and chromatography-immunoreactivity relationship of polysaccharides from Dioscorea opposite Thunb

The quality evaluation of Dioscorea opposite Thunb. mainly focuses on determining water-soluble contents. Polysaccharides are now recognized as the significant constituents of yam with activities such as immune enhancement, and it is necessary to use polysaccharides as an indicator for quality control of yam in this study. Sixty batches of yam polysaccharides were obtained by conventional hot water extraction and analysis for their physicochemical properties and structure. The results showed the functional groups (four shared peaks including 3500–3300 cm−1) and molecular weights (2.06 × 103 Da-2.28 × 103 Da). The PMP-HPLC fingerprints calibrated 5 familiar peaks, and the relative retention times of each characteristic peak to the Glc peak (S peak) were 0.47 (Man), 0.86 (GalA), 1.00 (Glc), 1.13 (Gal), 1.24 (Ara), Glc and Gal, which were the main differentiated monosaccharide components in the HPLC fingerprinting of YPs. This study provided a preliminary data reference for quality control of YPs.

Structural properties and biological effects of pectic polysaccharides extracted from Tartary buckwheat sprouts by high pressure-assisted deep eutectic solvent extraction

Tartary buckwheat sprout is commonly consumed as salads and healthy vegetables, which is rich in pectic polysaccharides. Nevertheless, the knowledge about pectic polysaccharides extracted from Tartary buckwheat sprouts (TBSP) are still limited. To facilitate the potential applications of TBSP as fortified ingredients or healthy foods, the impacts of conventional hot water extraction (CHW), deep eutectic solvent (DES)-assisted extraction (DEE), and high pressure-assisted DES extraction (HPDEE) on their structural and biological properties were evaluated. Compared with the CHW method, our findings revealed that both DEE and HPDEE methods could obviously promoted the yields of TBSP and regulated their structural properties, resulting in the improvement of their biological functions. Especially, the HPDEE method could obviously decreased the molecular mass, apparent viscosity, and esterification degree of TBSP, while notably increased the uronic acids and bound flavonoids. Indeed, the HPDEE method could remarkedly enhance the antioxidant, anti-glycosylation, and immunostimulatory activities of TBSP probably via reducing its molecular mass and degree of esterification, and increasing its free uronic acids and bound flavonoids. These findings reveal that the HPDEE method has good potentials for selectively extracting distinctive TBSP with superior biological functions.

Sustainable valorisation of bioactive molecules from rice husks through hydrothermal extraction for chitosan-based bioplastic production

Rice husks are a low value byproduct, even though it possesses molecules with great potential, such as arabinoxylans, proteins, and silica. These molecules can be used to improve mechanical and physicochemical properties of materials for food packaging. In this work, hydrothermal treatment was used for a sustainable extraction of the valuable molecules present in rice husks. Various extraction temperatures (180, 200, and 220 °C) were performed targeting to extract fractions with distinct compositions. The water extract obtained at 220 °C demonstrated the highest extraction yield, 3 times superior to conventional hot water extraction. These extracts exhibited high content of proteins, phenolic compounds, and carbohydrates, particularly arabinoxylans. This extract was incorporated in chitosan-based films in different ratios, 1:0.1, 1:0.3, and 1:0.5 (chitosan:extract, w:v). The film with the lowest extract ratio presented the highest flexibility (higher elongation and lower Young's modulus) when compared to the pristine chitosan film. The antioxidant capacity was also increased, achieving an antioxidant capacity of >10-fold in comparison to control film. The results revealed that hydrothermal extraction emerges as an environmentally friendly and sustainable methodology for extracting valuable compounds from rice industry byproducts. This method exhibits significant potential to impart flexible and antioxidant properties to biobased materials.

Optimization of Plasma Activated Water Extraction of Pleurotus ostreatus Polysaccharides on Its Physiochemical and Biological Activity Using Response Surface Methodology.

This study focused on optimizing the extraction of P. ostreatus polysaccharides (POPs) using plasma-activated water (PAW). A single factor and response surface methodology were employed to optimize and evaluate the polysaccharide yield, physiochemical characteristics, and biological activities of POPs. The observed findings were compared to those obtained by the conventional hot water extraction method (100 °C, 3 h), as the control treatment. The optimal extraction conditions were obtained at 700 W PAW power, 58 s treatment time, 1:19 sample-to-water ratio, and 15 L/min gas flow rate. In these conditions, the PAW-treated samples experienced changes in surface morphology due to plasma etching, leading to a 288% increase in the polysaccharide yield (11.67%) compared to the control sample (3.01%). Furthermore, the PAW-treated sample exhibited superior performance in terms of biological activities, namely phenolic compounds (53.79 mg GAE/100 g), DPPH scavenging activity (72.77%), and OH scavenging activity (65.03%), which were 29%, 18%, and 38% higher than those of control sample, respectively. The results highlighted the importance of process optimization and provided new evidence for PAW as an alternative approach to enhance the extraction efficiency of POPs, a novel source of natural antioxidants which enables diverse applications in the food industry.

Extraction of Ampelopsis japonica polysaccharides using p-toluenesulfonic acid assisted n-butanol three-phase partitioning: Physicochemical, rheological characterization and antioxidant activity

Polysaccharides as the biopolymers are showing various structural and modulatory functions. Effective separation of carbohydrate structures is essential to understanding their function. In this study, we choose an efficient organic acid in combination with recyclable organic solvent three-phase partitioning technology for the simultaneous extraction of polysaccharides from Ampelopsis japonica (AJPs) to ensure the integrity of linear and branched polysaccharide. The monosaccharide composition, glycosidic linkage information, structural and physicochemical analyses and associations with antioxidant activities were extensively analyzed. Synergistic extraction was compared with the conventional hot water extraction method and the results showed that AJPs-HNP exhibited better elastic properties and excellent antioxidant activity. Correlation analysis confirmed that the antioxidant activity of AJPs was significantly correlated with relative molecular weight, uronic acid content and terminal glycoside linkage molar ratios. The collaborative processing has significantly improved the utilization potential of AJPs and provides a sound theoretical foundation for the effective extraction and separation of polysaccharides. Overall, this work provides systematic and comprehensive scientific information on the physicochemical, rheological and antioxidant properties of AJPs, revealing their potential as natural antioxidants in the functional food and pharmaceutical industries.

Characterization of pectin extracted from pomelo peel using pulsed ultrasound assisted extraction and acidic hot water extraction process

In the present study, the characteristic properties namely XRD, FTIR, DSC, TGA and FESEM analyses of pectin extracted from pomelo fruit peel using pulsed ultrasound assisted extracted (PUUAE) were compared with those of pectin obtained with the conventional acidic hot water extraction (AHWE) process. The pectin extracted from PUUAE process has been analysed to possess better properties in comparison with the pectin obtained from the AHWE process. Pectin obtained from these two methods had been of high methoxyl pectin with almost similar structure. XRD analysis confirmed that AHWE based pectin possessed lower crystallinity than the PUUAE based pectin. The XRD spectra of PUUAE pectin affirmed sharper and stronger peaks than those of the AHWE based pectin and especially at 18.33° and 29.04° Further, the FTIR study revealed stronger absorption areas for PUUAE based pectin than those pertinent in the AHWE based pectin. This inferred that the pectin extracted with PUUAE had higher degree of esterification than that obtained with the AHWE process. Moreover, the DSC and TGA analyses indicated that PUUAE pectin had higher thermal stability in comparison to AHWE based pectin. The exothermic transition for the PUUAE based pectin was found to occur at higher temperature (245.7 °C) in comparison to the AHWE based pectin sample (239 °C). The TGA study conveyed double-stage decomposition for the PUUAE pectin sample (two DTGA peak temperatures (first at 230 °C and the second at 317 °C)) in comparison to the data obtained for the AHWE based pectin sample (a single peak only appears at 182 °C). The FESEM study affirmed a smoother surface with more structural integrity for PUUAE based pectin than that pertinent in the AHWE pectin sample. Therefore, the obtained characteristics can be inferred to the view that the PUUAE process is effective for the production of high quality pectin from pomelo peel (PP) for relevant functional applications.

Economic analysis of enzyme recycling during enzymatic hydrolysis of sugar beets for soluble sugars production

AbstractEnzymatic hydrolysis of sugar beets is an efficient alternative to conventional hot water extraction where overall soluble extraction is valued. The economic analysis of a sugar beet soluble sugar production plant was designed and developed using SuperPro Designer software. The commercial scale operation was sized to process 100 million metric ton (MT)/day of sugar beets. The base case process includes transportation, grinding, thermal pretreatment, enzymatic hydrolysis, solid–liquid separation, and evaporation. The final product from the model was assumed to be a sugar syrup stream at 65% total solids content. Since the breakeven selling price was sensitive to the cost of enzymes, alternative scenario A added an ultrafiltration unit operation to separate the enzymes and reuse them in subsequent batches of hydrolysis. Steam was another major contributor to the operating cost. Alternative scenario B included a natural gas boiler to generate steam from biogas produced from a co‐located dairy manure digester. The breakeven selling price of the sugar syrup from the base case, alternative scenario A, and alternative scenario B were $965, $911, and $955 per metric ton, respectively. Sensitivity analysis showed that the breakeven selling price is sensitive to the raw material cost, especially for the pectic enzymes.

Natural deep eutectic solvents for Ultrasonic-Assisted extraction of nutritious date Sugar: Molecular Screening, Experimental, and prediction

The aim of this study is to develop an environmentally friendly and effective method for the extraction of nutritious date sugar using natural deep eutectic solvents (NADES) and ultrasound-assisted extraction (USAE). The careful design of a suitable NADES-USAE system was systematically supported by COSMO-RS screening, response surface method (RSM) and artificial neural network (ANN). Initially, 26 natural hydrogen bond donors (HBDs) were carefully screened for sugar affinity using COSMO-RS. The best performing HBDs were then used for the synthesis of 5 NADES using choline chloride (ChCl) as HBA. Among the synthesized NADES, the mixture of ChCl, citric acid (CA) and water (1:1:1 with 20 wt% water) resulted in the highest sugar yield of 78.30 ± 3.91 g/100 g, which is superior to conventional solvents such as water (29.92 ± 1.50 g/100 g). Further enhancements using RSM and ANN led to an even higher sugar recovery of 87.81 ± 2.61 g/100 g, at conditions of 30 °C, 45 min, and a solvent to DFP ratio of 40 mL/g. The method NADES-USAE was then compared with conventional hot water extraction (CHWE) (61.36 ± 3.06) and showed 43.1% higher sugar yield. The developed process not only improves the recovery of the nutritious date sugar but also preserves the heat-sensitive bioactive compounds in dates, making it an attractive alternative to CHWE for industrial utilization. Overall, this study shows a promising approach for the extraction of nutritive sugars from dates using environmentally friendly solvents and advanced technology. It also highlights the potential of this approach for valorizing underutilized fruits and preserving their bioactive compounds.

Parametric analysis and machine learning for enhanced recovery of high-value sugar from date fruits using supercritical CO2 with co-solvents

The extraction of date sugar using supercritical extraction is a process that is still in its formative stages. In this study, a comprehensive parametric analysis of the supercritical fluid extraction (SFE) process using supercritical CO2 with water/ethanol as co-solvents was performed to achieve maximum recovery of date sugar extract. The results showed that the maximum total sugar content (TSC) was 70.45 ± 0.01 g/100 g of DFP. This was made up of 7.42 g/100 g fructose, 6.49 g/100 g glucose, and 56.54 g/100 g sucrose. This was attained with 15 v/v% water as co-solvent, 50 ℃, and 200 bar. In addition, machine learning with non-linear regression and artificial neural network (ANN) ensembles was used for TSC prediction. The ANN results showed a strong correlation between operating parameters and sugar recovery with a total R2 of 0.986 ± 0.010. Compared to conventional hot water extraction method (CHWE), the CO2-SFE process resulted in a 1.4-fold increase in TSC recovery and a 2.1-fold increase in organic acids recovery. CO2-SFE demonstrated comparable TSC results with a difference of only 1.2% when compared to the ultrasound-assisted extraction ‘'USAE’ method. The results of the detailed chemical analysis (HPLC and FT-IR) and morphological analysis (SEM) showed that the USAE and CO2-SFE were more efficient than CHWE. Supercritical extraction with co-solvents is particularly effective in recovering date sugar from date fruit, making it a desirable ingredient in a variety of food products.

Subcritical Water Extraction of Mango Seed Kernels and Its Application for Cow Ghee Preservation

Mango seed kernel (MSK) extract contains phytochemicals, bioactives, and fatty acids that are of interest to food and nutritional scientists. The subcritical water extraction process (SCWE) can be effective in extracting valuable bioactives from MSK. In this study, SCWE was investigated and optimized for the extraction of bioactives from MSK using Box–Behnken experimental design. The extract yield was examined as a function of various process variables, namely, solvent-to-feed (L/S) ratio, extraction temperature (T), and extraction time (t). Analysis of variance (ANOVA) for experimental results showed that extraction temperature was the most significant variable that impacted the extract yield. A maximum yield of 52.3% was obtained at optimized extraction conditions of L/S ratio = 20.7, T = 116.5 °C, and t = 45 min. Antioxidant assessment of the SCWE extract obtained at the optimized conditions showed higher total phenolic content (19.2 mg GAE/g), and DPPH and ABTS radical scavenging activity (>91%), than the extracts obtained by conventional hot water extraction and ultra-sound assisted extraction. Furthermore, an assessment of the MSK extract as a natural preservative showed that its inclusion (20% v/v) improved the oxidative stability of cow ghee with a par performance to synthetic butylated hydroxyanisole antioxidant (0.02% w/v). Thus, the study demonstrated SCWE as an effective green method for the production of MSK extract that could be applied for the preservation of oxidative food products.

Ultrasound-Assisted Deep Eutectic Solvent Extraction of Polysaccharides from Anji White Tea: Characterization and Comparison with the Conventional Method.

Deep eutectic solvent as a new green and safe solvent system has attracted more and more attention in recent years. In this study, three deep eutectic solvents (DES) were combined with ultrasound irradiation to extract tea polysaccharides (TPs) from Anji white tea, which was compared with conventional hot water extraction (HW). The physicochemical, structural, and biological properties of TPs extracted by ultrasound-assisted DES and hot water (HWP) were further investigated. Results showed that the DES system composed of choline chloride and 1,6-hexanediol (CH) with the molar ratio of 1:2 exhibited the optimal extraction yield (19.18%) and in vitro antioxidant activities for TPs (CHP). Furthermore, compared to the HWP, the CHP had a higher extraction yield and total carbohydrate content and a lower molecular weight. Monosaccharide composition analysis displayed that the molecular structure of CHP exhibited more arabinose but less glucose, mannose, galacturonic acid, and glucuronic acid than HWP. Little difference was observed in the preliminary structural characteristics between HWP and CHP from Fourier transform infrared analysis. Besides, CHP possessed better α-glucosidase inhibitory and hypoglycemic activity in L6 cells than HWP. Therefore, the ultrasound-assisted DES extraction method can be a promising strategy for extracting TPs with excellent bioactivities for future applications in functional foods.

Cellular antioxidant and emulsifying activities of fucoidan extracted from Nizamuddinia zanardinii using different green extraction methods

AbstractIn the present study, fucoidan was extracted from Nizamuddinia zanardinii samples using nine different green extraction techniques in addition to the conventional hot water extraction method (HW). Antioxidant (chemical and cellular assays) and emulsifying activities as well as optical properties of the different extracted fucoidans were investigated. The chemical composition and molecular weight of the fucoidans were also discussed. The results showed that fucoidan extracted using microwaves and a combination of ultrasound and microwaves (UM) exhibited the highest DPPH scavenging activity (72%) and reducing power (0.37–0.39 Abs). Moreover, all extracted fucoidans showed good cytoprotective effects on H2O2‐induced damage and inhibition of reactive oxygen species formation in HepG2 cells, and the fucoidan extracted by UM exhibited the highest activity (59.51–69.06%). Additionally, the fucoidans isolated by green techniques showed higher emulsification capacity than those isolated by HW method. Based on the obtained results, the method UM can be recommended for the extraction of fucoidans from N. zanardinii samples.Novelty impact statementFucoidan is a sulfated polysaccharide extracted from brown seaweeds with various bioactivities. In recent years, industry prefer the greener and faster methods to obtain bioactive compounds. In this regard, further studies are needed to determine the bioactivity of compounds extracted by environmentally friendly methods. In the present study, impact of different green extraction methods on the antioxidant and emulsifying activity of fucoidans from N. zanardinii were investigated for the first time. The results confirmed that fucoidans extracted by green methods has antioxidant activity in both chemical and cellular models and also exhibits emulsifying activity. On this basis, the extracted fucoidans can be used for the development of dietary supplements for humans and can also be incorporated into food formulation for the production of functional foods.

Subcritical water extraction for recovery of phenolics and fucoidan from New Zealand Wakame (Undaria pinnatifida) seaweed

In this study, subcritical water extraction (SWE) was investigated for the recovery of phenolics, phlorotannins, and fucoidan from New Zealand Wakame. Maximum total phenolics and phlorotannin content of 29.9 mg ± 1.8 mg gallic acid equivalent/g dry weight seaweed (mg GAE/g dw) and 0.99 mg ± 0.004 mg phloroglucinol equivalents (PGE)/g dw respectively were achieved at 210 °C, at a solid content of 10 g/L, and at 15–20 min. Maximum fucoidan yield of 46 mg/g dw was obtained at 120 °C, 5 min, and 20 g/L. In comparison, conventional hot water extraction (HWE) achieved lower phenolic and phlorotannin content at 1.27 mg ± 0.01 mg GAE/g dw and 0.69 mg ± 0.1 mg PGE/g dw respectively. Also, fucoidan was not detected by HWE and antioxidant activity was much lower compared to SWE. These results indicate the effectiveness of SWE as an alternative to conventional extraction methods.

A comparative study on the structural and functional properties of water‐soluble and alkali‐soluble dietary fibres from rice bran after hot‐water, ultrasound, hydrolysis by cellulase, and combined pre‐treatments

SummaryThe aim of the study was to estimate the optimum method to obtain water‐soluble (WS‐DF) and alkali‐soluble (AS‐DF) dietary fibres fibres from defatted rice bran (DRB) to develop functional components for food. The different pre‐treatments of DRB, such as ultrasound (US) treatment, hydrolysis by cellulase (HC) and combined treatment (HC‐US), were compared with hot‐water (HWT) treatment on yields, and structural, physicochemical, and functional properties of WS‐DF and AS‐DF. Results showed that amounts of WS‐DF (5.54–9.03 g/100 g) and AS‐DF (7.22–9.58 g/100 g), and total dietary fibre (TDF) (42.21–45.44 g/100 g) obtained from the DRB after US, HC and HC‐US treatments were significantly higher than that after HWT (6.36, 5.65 and 31.92 g/100 g, respectively). The FT‐IR indicated that the effect of applied treatments on the changes of the chemical structure of polysaccharides was stronger for the WS‐DF than that for the AS‐DF. Scanning electron microscopy (SEM) showed that the surfaces of US‐treated DFs particles were much more fractured than those after the HWT and HC. The combined HC‐US treatment at 50°C for 30 min significantly enhanced the purity (85–91%) and homogeneity of RB DFs structure resulting in increased water‐holding, swelling and glucose adsorption capacities compared to conventional processes maintaining acceptable bioactivity. Our study showed that conventional hot water extraction could be replaced with the ultrasonication technology as an effective tool for the modification of rice bran DFs’ structure and functional properties.

Quantitative selenium speciation in feed by enzymatic probe sonication and ion chromatography-inductively coupled plasma mass spectrometry

ABSTRACT A rapid, sensitive and species preservative analytical method for the simultaneous determination of six selenium (Se) species has been developed. Enzymatic probe sonication (EPS) was investigated as a novel and alternative technology for the extraction of Se species from feed matrices and the results were compared with the conventional hot water extraction, enzymatic hydrolysis and sequential extraction. The critical parameters of EPS such as enzyme types, extraction time, temperature, ultrasonic power and sample/enzyme ratio were varied with control. The Se species were separated and quantitatively determined by ion chromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS). Under current optimised conditions, six inorganic and organic Se species were completely separated within 15 min in a single chromatographic run. The spectral interferences from the argon plasma 40Ar2, 40Ar37Cl or 1H79Br were effectively removed by employing the kinetic energy discrimination (KED) mode. Quantitative extraction for total Se (>94.8%) and more than 89.0% for the sum of different Se chemical forms without species transformation were obtained in only 60 s by applying the EPS treatment using aqueous protease XIV. The limits of detection (LODs) and quantification (LOQs) for Se species were in the ranges of 0.21–0.56 µg kg–1 and 0.69–1.87 µg kg–1, respectively. The proposed method was successfully applied to the speciation of Se in several reference materials and feed samples collected from the markets and local farms.

Data of microwave assisted extraction and conventional hot water extraction of Dendrobium Sonia 'Earsakul' orchid flower.

Crude extracts of fresh Dendrobium Sonia ‘Earsakul’ orchid flowers (DSE) were prepared using microwave assisted extraction (MAE; using household microwave oven) and hot water extraction (HWE; at constant 80 °C). The obtained DSEs were measured their absorbance at λmax of 543 and 583 nm and determined their total monomeric anthocyanin contents (TAC). Mathematical models of MAE of Dendrobium Sonia ‘Earsakul’ orchid flower were constructed using response surface methodology - Box-Behnken design. Studied parameters included flower to water ratio, microwave power, and extraction time, with absorbance at λmax as response. The data generated were 1) visible spectrum (400–700 nm) of DSE; 2) absorbance values at λmax and 3) TAC of DSEs obtained from various extraction conditions of MAE and HWE; 4) linear equations describing correlations between TAC and absorbance at λmax of DSEs; and 5) mathematical models of MAE of Dendrobium Sonia ‘Earsakul’ orchid.

Deep Eutectic Solvents Based Ultrasonic Extraction of Polysaccharides from Edible Brown Seaweed Sargassum horneri

In this work, a method for ultrasonic extraction of polysaccharides from Sargassum horneri using deep eutectic solvents was proposed. The studied deep eutectic solvents were composed of choline chloride, 1,2-propanediol and water. Based on the single-factor experiment results, four experimental factors were systematically evaluated, giving the optimal extraction conditions as follows: molar ratio of choline chloride to 1,2-propanediol of 1:2, water content of 30% (v/v), solid-liquid ratio of 1:30 (g/mL), and the extraction temperature of 70 °C. Fourier transform infrared spectroscopy and X-ray diffraction were utilized to investigate changes in the chemical characteristic of extracted polysaccharides. The results indicated that deep eutectic solvents had stronger protein and calcium carbonate removal ability than that of a conventional hot water extraction method. Moreover, in vitro antioxidant activity tests exhibited that the obtained polysaccharides had significant inhibition effects on DPPH and ABTS radicals. The proposed deep eutectic solvents assisted ultrasonic extraction protocol was considered to be a green, fast and effective protocol for extracting polysaccharides from Sargassum horneri.

Effects of pressurized hot water extraction on the yield and chemical characterization of pectins from Campomanesia xanthocarpa Berg fruits

Pressurized hot water extraction (PHWE), known as a “green” extraction technique, was used to obtain polysaccharide from the pulp of gabiroba (Campomanesia xanthocarpa Berg) fruits. The effects of pressure, temperature, and flow rate on pectin yields were analyzed through a full factorial design experiment 23. The optimal extraction conditions to achieve maximum pectin yield (5.70 wt%) were pressure of 150 bar, temperature of 120 °C, and flow rate of 1.5 mL min−1. The high pressure (100 bar) promoted an increase in galacturonic acid content (36.0%) compared to conventional hot water extraction (CEGP) with 25.7%. Differences in the proportion of homogalacturonan (HG) and rhamnogalacturonan (RG-I) domains ranging from 16.3 to 35.4% and 61.7 to 80.1%, respectively, were observed for each pectin sample according to the extraction conditions. The mono-dimensional (13C-NMR) and bi-dimensional (1H/13C HSQC-NMR) analyses confirmed the presence of HG and RG-I regions and indicated the presence of arabinogalactans type I (AG-I) and arabinogalactans type II (AG-II) in the PHWE pectin samples, which was not found for pectins from gabiroba pulp obtained by CEGP. The results showed that PHWE proved to be a promising method for extracting pectins from gabiroba fruits.

Coronary Vasculitis Induced in Mice by Cell Wall Mannoprotein Fractions of Clinically Isolated Candida Species.

Kawasaki disease (KD) is an inflammatory disease that was identified by Professor Tomisaku Kawasaki in 1961. Candida albicans-derived substances (CADS) such as the hot water extract of C. albicans and Candida water-soluble fractions (CAWS) induce coronary vasculitis similar to KD in mice. An increasing proportion of deep-seated candidiasis cases are caused by non-albicans Candida and are often resistant to antifungal drugs. We herein investigated whether the mannoprotein fractions (MN fractions) of clinically isolated Candida species induce vasculitis in mice. We prepared MN fractions from 26 strains of Candida species by conventional hot water extraction and compared vasculitis in DBA/2 mice. The results obtained revealed that the induction of vasculitis and resulting heart failure were significantly dependent on the species; namely, death rates on day 200 were as follows: Candida krusei (100%), Candida albicans (84%), Candida dubliniensis (47%), Candida parapsilosis (44%), Candida glabrata (32%), Candida guilliermondii (20%), and Candida tropicalis (20%). Even for C. albicans, some strains did not induce vasculitis. The present results suggest that MN-induced vasculitis is strongly dependent on the species and strains of Candida, and also that the MN fractions of some non-albicans Candida induce similar toxicity to those of C. albicans.

Ultrasound assisted extraction of the polysaccharide from Tuber aestivum and its in vitro anti-hyperglycemic activity

Tuber aestivum is one of the most popular and delicious truffles in the world economic market and is reported to possess a wide range of biological activities. The total carbohydrate of this truffle constitutes about 5.65% w/w dry weight basis (dwb). The present work compares the yield of the polysaccharide obtained by conventional hot water extraction followed by alcohol precipitation, and ultrasound assisted extraction using low power 150 W probe sonifier. The parameters of ultrasound assisted extraction (amplitude, extraction time, pH, and liquid-solid ratio) from the fruiting body of T. aestivum were optimized using Taguchi orthogonal array and central composite design. The optimal parameters of extraction were a liquid-solid ratio of 75:1 for 15 min at pH 6.5 at an amplitude of 25%, which yielded 68.91 ± 1.54% w/w dwb polysaccharide. The FTIR and SEM characteristics of the polysaccharides obtained by ultrasonic extraction and conventional hot water extraction were similar. Further, the polysaccharides extracted from T. aestivum demonstrated a significant in vitro anti-hyperglycemic activity.