Synthesis, mechanisms of action, and toxicity of novel aminophosphonates derivatives conjugated irinotecan in vitro and in vivo as potent antitumor agents.

Twenty novel aminophosphonates derivatives (5a-5j and 6a-6j) conjugated irinotecan were synthesized through esterification reaction, and evaluated their anticancer activities using MTT assay. In vitro evaluation revealed that they displayed similar or superior cytotoxicity compared to the positive drug irinotecan against A549, MCF-7, SK-OV-3, MG-63, U2OS and multidrug-resistant (MDR) SK-OV-3/CDDP cancer cell lines. Among them, 9b displayed the most potent activity, with IC50 values of 0.92-3.23 µM against five human cancer cells, which exhibited a 5.4-19.1-fold increase in activity compared to the reference drug irinotecan, respectively. Moreover, cellular mechanism studies suggested that 9b arrested cell cycle at S stage and induced cell apoptosis along with the decrease of mitochondrial membrane potential (MMP). Interestingly, 9b significantly inhibited tumor growth in SK-OV-3 xenograft models in vivo without apparent toxicity, which was better than the positive drug irinotecan. Taken together, 9b possessed potent antitumor activity and may be a promising candidate for the potential treatment of human ovarian cancer cells.

Synthesis and biological evaluation of novel millepachine derivative containing aminophosphonate ester species as novel anti-tubulin agents.

A new series of millepachine derivative containing aminophosphonate ester moieties were designed and synthesized, and evaluated for their anticancer activities using MTT assay. Among all the compounds, compound 9m exhibited the most potent cytotoxic activity against all tested human cancer cell lines including multidrug resistant phenotype, which inhibited cancer cell growth with IC50 values ranging from 0.85 to 3.09 µM, respectively. In addition, its low cytotoxicity toward human normal liver cells HL-7702 and sensitivity toward to doxorubicin or cisplatin-resistant cells indicated the possibility for cancer therapy. Furthermore, 9m significantly induced cell apoptosis and cell cycle arrest in G2/M phase and dramatically disrupted the microtubule organization. Moreover, a decrease in MMP, an increase in reactive oxygen species (ROS) generation and Bax/Bcl-2 ratio, accompanied by activated caspase-3 and -9, were observed in HepG-2 cells after incubation with 9m, indicating that the mitochondrial pathway was involved in the 9m-mediated apoptosis.

Dual-targeting antitumor conjugates derived from platinum(IV) prodrugs and microtubule inhibitor CA-4 significantly exhibited potent ability to overcome cisplatin resistance.

Here we report that three platinum(IV) prodrugs containing a tubulin inhibitor CA-4, as dual-targeting platinum(IV) prodrug, were synthesized and evaluated for antitumor activity using MTT assay. Among them, complex 9 exhibited the most potent antitumor activity against the tested cancer lines including cisplatin resistance cancer cells, and simultaneously displayed lower toxicity compared to cisplatin, respectively. Moreover, complex 9, in which was conjugated to an inhibitor of tubulin at one axial position of platinum(IV) complex, could effectively enter the cancer cells, and significantly induce cell apoptosis and arrest the cell cycle in A549 cells at G2/M stage, and dramatically disrupt the microtubule organization. In addition, mechanism studies suggested that complex 9 significantly induced reactive oxygen species (ROS) generation and decreased mitochondrial trans-membrane potential (MMP) in A549 cells, and effectively induced activation of caspases triggering apoptotic signaling through mitochondrial dependent apoptosis pathways.

Intensification of biodiesel production using dual-frequency counter-current pulsed ultrasound.

Biodiesel production from soybean oil deodorizer distillate intensified by dual-frequency counter-current pulsed ultrasound and the kinetics were studied. Results indicated that the biodiesel conversions enhanced by single-frequency were lower than those enhanced by dual-frequency. For dual-frequency, the biodiesel conversion of SMM was higher than those of SQM. The biodiesel conversion of the combination of 20/28kHz is the highest. The effects of 20/28kHz SMM on biodiesel production were studied and optimal conditions were: methanol to triglyceride molar ratio 8:1, catalyst content 1.8%, the water content in feedstock should be less than 0.4%, the acid value of feedstock should be less than 2mgKOH·g-1, the biodiesel conversion could reach 96.3%. The kinetics of SMM and SSPU were studied and results showed that the transesterification reaction was pseudo-second order and the energy activation obtained by SMM and SSPU were 18.122kJ·mol-1 and 26.034kJ·mol-1, respectively. These results showed that transesterification reaction intensified by SMM is easier to take place than SSPU.

Optimization for ultrasonic-microwave synergistic extraction of polysaccharides from Cornus officinalis and characterization of polysaccharides.

Ultrasonic-microwave synergistic extraction (UMSE) of polysaccharides from Cornus officinalis was optimized by response surface methodology (RSM). The effect of four different factors on the yield of C. officinalis polysaccharides (COP) was studied. RSM results showed that the optimal conditions were extraction time of 31.49823 min, microwave power of 99.39769 W, and water-to-raw material ratio of 28.16273. The COP yield was 11.38±0.31% using the modified optimal conditions, which was consistent with the value predicted by the model. The crude COP was purified by DEAE-Cellulose 52 chromatography and Sephadex G-100 chromatography. Five fractions, namely, crude COP, COP-1, COP-2, COP-3, and COP-4, were obtained. Monosaccharide composition analysis revealed that the COP was composed of glucose, arabinose, fucose, xylose, mannose, and rhamnose. Preliminary structural characterizations of COP were conducted by scanning electron microscopy and Fourier transform infrared spectroscopy.

Complex Enzyme-Assisted Extraction, Purification, and Antioxidant Activity of Polysaccharides from the Button Mushroom, Agaricus bisporus (Higher Basidiomycetes).

Agaricus bisporus polysaccharides (ABP) were extracted by complex enzyme-assisted extraction methodology. The following were optimal conditions for the extraction of crude ABP: complex enzyme amount, 2.2%; temperature, 62°C; time, 3 h; and pH, 4. Under these conditions, the experimental yield of crude ABP was 6.87%. The crude ABP was purified by diethylaminoethyl-cellulose 52 chromatography and Sephadex G-100 chromatography, and one fraction-namely, ABP-1-was produced. The ABP-1 contained 93.67% carbohydrate, 1.46% protein, and 0.62% uronic acid. The constituent monosaccharides were predominantly glucose, galactose, mannose, and xylose. The antioxidant activities of ABP-1 were investigated by measuring its scavenging ability on 2,2-diphenyl-1-picrylhydrazyl and hydroxyl radicals, its ferric-reducing activity power, and the reducing power assay. At a concentration of 1.2 mg/mL, ABP-1 seemed to possess good free radical scavenging activity, with a scavenging value of about 56%. The results indicate that ABP-1 has good antioxidant activity.

Biodiesel production from soybean oil deodorizer distillate enhanced by counter-current pulsed ultrasound.

Biodiesel production from soybean oil deodorizer distillate enhanced by counter-current pulsed ultrasound was studied. Effect of static probe ultrasonic enhanced transesterification (SPUE) and counter-current probe ultrasonic enhanced transesterification (CCPUE) on the biodiesel conversion were compared. The results indicated that CCPUE was a better method for enhancing transesterification. The working conditions of CCPUE were studied by single-factor experiment design and the results showed that the optimal conditions were: initial temperature 25 °C, methanol to triglyceride molar ratio 10:1, flow rate 200 mL/min, catalyst content 1.8%, ultrasound working on-time 4 s, off-time 2 s, total working time 50 min. Under these conditions, the average biodiesel conversion of three experiments was 96.1%.

Extraction and purification of polysaccharides from pine medicinal mushroom, Tricholoma matsutake (higher Basidiomycetes) fruit bodies.

Ultrasound-assisted extraction, purification, and characterization of antioxidant polysaccharides from Tricholoma matsutake were carried out. On the basis of the results of a single-factor test, three independent and main variables, including extraction time (X1: 130-170 s), ultrasonic power (X2: 340-380 W), and ratio of water to raw material (X3: 45-55 mL/g) were studied by Box-Behnken design. The optimum extraction conditions are as follows: extraction time 160 s, ultrasonic power 365 W, and ratio of water to raw material 53.5 mL/g. Under the optimized conditions, the yield of T. matsutake polysaccharides (TMP) was 7.97±0.31%. The crude TMP was purified by DEAE-cellulose 52 chromatography and Sephadex G-100 chromatography to afford two fractions, TMP-1 and TMP-2. The crude TMP contained 85.76% carbohydrates, 3.57% proteins, and 0.13% uronic acids. The constituent monosaccharides were predominantly glucose, galactose, mannose, xylose, fucose, and glucuronic acid residues.

A comparison study on extraction of polysaccharides from Tricholoma matsutake by response surface methodology.

The Tricholoma matsutake polysaccharides (TMP) extraction was optimized using counter-current probe ultrasonic extraction (CCPUE) by response surface methodology (RSM). The effect of three factors (liquid-solid ratio, extraction time and pulse duration) on the TMP yield was studied. The results showed that the optimal conditions were liquid-solid ratio (15), extraction time (61 min) and pulse duration (6.0 s). Under best conditions, the maximum TMP yield was 8.11 ± 0.35%, which was close with the predicted yield value (8.03%). The five methods, hot-water extraction (HWE), enzyme assisted extraction (EAE), ultrasonic clearer extraction (UCE), static probe ultrasonic extraction (SPUE), and CCPUE for extracting TMP by RSM were further compared. The results indicated that CCPUE had the largest yield of TMP with modest energy consumption.

Extraction, purification, and antioxidant activities of polysaccharides from Tricholoma mongolicum Imai.

Ultrasonic-microwave synergistic extraction (UMSE), purification, and characterization of Tricholoma mongolicum Imai polysaccharides (TMIPs) from fruit bodies were investigated in this study. Response surface methodology (RSM) was employed to optimize the UMSE conditions. The results indicated that the optimal extraction conditions were as follows: extraction time of 24.65 min, microwave power of 109.98 W, and water to raw material ratio of 21.62 ml/g. Under optimized conditions, the yield and purity of TMIPs were 35.41 ± 0.62% and 73.92 ± 0.83%, respectively. Crude TMIPs were purified by DEAE-Cellulose 52 chromatography and Sephadex G-100 chromatography to afford four fractions, namely, TMIP-1, TMIP-2, TMIP-3, and TMIP-4. Preliminary TMIP characterization was conducted by Fourier transform infrared spectroscopy. TMIP antioxidant activities were investigated by measuring its scavenging ability on 2,2-diphenyl-1-picrylhydrazyl, hydroxyl radicals, ferric reducing activity power, and reducing power assay. The results indicated that TMIPs have good antioxidant activity.

Pulsed counter-current ultrasound-assisted extraction and characterization of polysaccharides from Boletus edulis.

Four methods for extracting polysaccharides from Boletus edulis, namely, hot-water extraction, ultrasonic clearer extraction, static probe ultrasonic extraction, and pulsed counter-current probe ultrasonic extraction (CCPUE), were studied. Results showed that CCPUE has the highest extraction efficiency among the methods studied. Under optimal CCPUE conditions, a B. edulis polysaccharide (BEP) yield of 8.21% was obtained. Three purified fractions, BEP-I, BEP-II, and BEP-III, were obtained through sequential purification by DEAE-52 and Sephadex G-75 chromatography. The average molecular weights of BEP-I, BEP-II, and BEP-III were 10,278, 23,761, and 42,736 Da, respectively. The polysaccharides were mainly composed of xylose, mannose, galactose, and glucose; of these, mannose contents were the highest. The antioxidant activities of the BEPs were further investigated by measurement of their ability to scavenge DPPH and hydroxyl radicals as well as their reducing power. The results indicated that the BEPs have good antioxidant activity.

Biodiesel production from Jatropha oil catalyzed by immobilized Burkholderia cepacia lipase on modified attapulgite.

Lipase from Burkholderia cepacia was immobilized on modified attapulgite by cross-linking reaction for biodiesel production with jatropha oil as feedstock. Effects of various factors on biodiesel production were studied by single-factor experiment. Results indicated that the best conditions for biodiesel preparation were: 10 g jatropha oil, 2.4 g methanol (molar ratio of oil to methanol is 1:6.6) being added at 3h intervals, 7 wt% water, 10 wt% immobilized lipase, temperature 35°C, and time 24h. Under these conditions, the maximum biodiesel yield reached 94%. The immobilized lipase retained 95% of its relative activity during the ten repeated batch reactions. The half-life time of the immobilized lipase is 731 h. Kinetics was studied and the Vmax of the immobilized lipases were 6.823 mmol L(-1). This immobilized lipase catalyzed process has potential industrial use for biodiesel production to replace chemical-catalyzed method.

Enzyme assisted extraction of polysaccharides from the fruit of Cornus officinalis.

Process of enzyme assisted extraction (EAE) of polysaccharides from Cornus officinalis was optimized by response surface methodology (RSM). The influence of four different factors on the yield of C. officinalis polysaccharides (COP) was studied. Results showed that the optimal conditions were compound enzyme amount of 2.15%, extraction pH of 4.2, extraction temperature of 55 °C and extraction time of 97 min. Under these conditions, the COP yield was 9.29±0.31%, which was well in agreement with the value predicted by the model. The three methods, EAE, hot water extraction (HWE), ultrasound-assisted extraction (UAE) for extracting COP by RSM were further compared. Results showed that EAE had the largest yield of polysaccharides with lower equipment cost.

Immunomodulatory activities of different solvent extracts from Tricholoma matsutake (S. Ito et S. Imai) singer (higher basidiomycetes) on normal mice.

The immunomodulatory activities of different solvent extracts from the culinary-medicinal mushroom Tricholoma matsutake were studied in vivo in normal mice. The extracts were prepared using different solvents in an order of increasing polarity. The immunomodulatory activities were investigated by measuring the thymus and spleen index, phagocytic rate of macrophage phagocytosis, delayed-type hypersensitivity, plaque-forming cell, and proliferation of splenocytes. Results demonstrated that water extract (WE) and n-butyl alcohol extract (BAE) of T. matsutake could enhance the immunity of mice significantly compared with the control group. Main components of WE and BAE were polysaccharides, proteins, and flavonoids; we presume that these may be the main immunomodulating and immuno-enhancing agents in T. matsutake.

Purification, immobilization and characterization of linoleic acid isomerase on modified palygorskite.

Linoleic acid isomerase from Lactobacillus delbrueckii subsp. bulgaricus 1.1480 was purified by DEAE ion-exchange chromatography and gel filtration chromatography. An overall 5.1% yield and purification of 93-fold were obtained. The molecular weight of the purified protein was ~41 kDa which was analyzed by SDS-PAGE. The purified enzyme was immobilized on palygorskite modified with 3-aminopropyltriethoxysilane. The immobilized enzyme showed an activity of 82 U/g. The optimal temperature and pH for the activity of the free enzyme were 30 °C and pH 6.5, respectively; whereas those for the immobilized enzyme were 35 °C and pH 7.0, respectively. The immobilized enzyme was more stable than the free enzyme at 30-60 °C, and the operational stability result showed that more than 85% of its initial activity was retained after incubation for 3 h. The K (m) and V (max) values of the immobilized enzyme were found to be 0.0619 mmol l(-1) and 0.147 mmol h(-1) mg(-1), respectively. The immobilized enzyme had high operational stability and retained high enzymatic activity after seven cycles of reuse at 37 °C.