Meng Luo

Northeast Forestry University, Charbin, Heilongjiang Sheng, China

Are you Meng Luo?

Claim your profile

Publications (125)333.81 Total impact

  • [Show abstract] [Hide abstract] ABSTRACT: Astragalosides (AGs) are triterpene saponins that uniquely occur in Astragalus species with multiple pharmacological activities. For the first time, we reported an elicitation strategy, using UV radiation (UV-A, UV-B, and UV-C), to enhance AG production in Astragalus membranaceus hairy root cultures (AMHRCs). The treatment of 32 day-old AMHRCs with 54 kJ/m2 dose of UV-B radiation was capable of achieving the maximum production of AGs, i.e. 3.431 ± 0.092 mg/g dry weight (DW), which was 1.30-fold higher as compared to the level in non-treated control (2.645 ± 0.073 mg/g DW). Expressions of eleven genes involved in AG biosynthetic pathway were monitored by quantitative real-time PCR (qRT-PCR). Transcriptional results showed that only the HMGR gene was significantly up-regulated in response to UV-B elicitation. The present study demonstrated that UV-B elicitation is a feasible strategy to promote AG production in AMHRCs and that HMGR represents a potential key gene in AG biosynthetic pathway.
    No preview · Article · Jun 2016 · Industrial Crops and Products
  • [Show abstract] [Hide abstract] ABSTRACT: Geraniin, a typical ellagitannin isolated from Phyllanthus urinaria Linn, has been found to possess a range of bioactive properties. In the present study, we found that Geraniin showed potent anti-proliferative effects on human breast cancer MCF-7 cells. The IC50 values were 9.94, 17.98 and 42.32 µM after 72-, 48- and 24-h treatment, respectively. Meanwhile, Geraniin could remarkably disrupt mitochondrial membrane potential and arrest S phase cell cycle. Western-blot analysis showed that Geraniin induced phosphorylation of the anti-apoptotic Bcl-2, and the cleavage of poly (ADP-ribose) polymerase (PARP) and caspase-3 in MCF-7 cells. Moreover, Geraniin treatment activated p38 mitogen-activated protein kinase (p38 MAPK) and the effect was blunted in MCF-7 cells with the treatment of a specific p38 inhibitor SB203580. Geraniin could generate intracellular reactive oxygen species (ROS), activate p38 MAPK then induce the apoptosis in MCF-7 cells, such phenomena was abrogated by pretreatment with N-acetyl-l-cysteine. In general, these results support the conclusion that Geraniin-induced apoptosis is mediated via ROS-mediated stimulation of p38 MAPK signaling.
    No preview · Article · Apr 2016 · Toxicology mechanisms and methods
  • [Show abstract] [Hide abstract] ABSTRACT: In this study, the effect of seasonal variations on Crataegus pinnatifida, changes in antioxidant activity and active components in C. pinnatifida leaves, roots, twigs, and fruits from May to October were investigated. Through correlation analysis of climatic factors and 7 phenolic compounds yield, the phenolic compounds content was positively correlated with temperatures and daytime. The correlation coefficient of temperatures and daytime were 0.912 and 0.829, respectively. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging and reducing power tests were employed to evaluate the antioxidant activity of the C. pinnatifida. C. pinnatifida leaves exhibited significant advantages in terms of higher phenolic contents and excellent antioxidant activities. Principal component analysis (PCA) revealed that 2 main PC characterize the C. pinnatifida phenolic composition (82.1% of all variance). C. pinnatifida leaves in September possessed remarkable antioxidant activity. The results elucidate that C. pinnatifida leaves, as renewable parts, are suitable for application as antioxidant ingredients.
    No preview · Article · Apr 2016 · Journal of Food Science
  • [Show abstract] [Hide abstract] ABSTRACT: In the present study, a highly effective extraction method, namely ultra-turrax based ultrasound-assisted extraction (UT-UAE), was firstly designed to extract the main organic acids from honeysuckle. Single factor experiments and Box-Behnken design (BBD) were conducted to optimize the extraction process. The optimal extraction conditions were as follows: homogeneous rate 8000 rpm, ultrasonic intensity 0.347 W/cm2, ethanol concentration 65%, time 10 min and liquid/solid ratio 20:1 mL/g. Moreover, the mass transfer kinetics and particle size distribution were investigated in order to demonstrate the advantages of UT-UAE. Through the comparison with ultra-turrax extraction (UTE) and ultrasound-assisted extraction (UAE) methods, the proposed method exhibited higher yields of five target organic acids in a shorter time. The results showed that UT-UAE could be a promising method for fast extracting active compounds from plants.
    No preview · Article · Apr 2016 · Separation and Purification Technology
  • [Show abstract] [Hide abstract] ABSTRACT: In this work, Astragalus membranaceus hairy root cultures (AMHRCs) were induced to boost isoflavonoid biosynthesis upon elicitations of methyl jasmonate (MJ), salicylic acid (SA) and acetylsalicylic acid (ASA). The optimal enhancement of isoflavonoid production was obtained in 34 day-old AMHRCs elicited by MJ under the concentration of 283 μM and the exposure time of 33.75 h. The resulting isoflavonoid yield was 2250.10 ± 71.88 μg/g dry weight (DW), which tremendously increased 9.71-fold relative to that of non-treated control (231.64 ± 6.51 μg/g DW). Moreover, transcriptions of eight isoflavonoid biosynthetic genes were significantly up-regulated in response to MJ elicitation, and chalcone isomerase and isoflavone synthase genes were found to be key regulatory nodes in isoflavonoid biosynthetic pathway. Additionally, an enormous increase was observed in antioxidant capacities of extracts from MJ-elicited AMHRCs (IC50 values: 0.51 and 0.72 mg/mL) as against those of non-treated control (1.39 and 1.71 mg/mL). Overall, this study offered a feasible strategy to promote isoflavonoid production in AMHRCs with higher antioxidant activity, and also paved the way for achieving isoflavonoid overproduction via metabolic manipulations in the future.
    No preview · Article · Feb 2016
  • [Show abstract] [Hide abstract] ABSTRACT: In this work, the elicitation of Astragalus membranaceus hairy root cultures (AMHRCs) with methyl jasmonate (MJ), salicylic acid (SA) and acetylsalicylic acid (ASA) was conducted to boost astragaloside (AG) biosynthesis. MJ was found to be the most effective inducer for AG production among all elicitor treatments. The highest enhancement of AG accumulation was achieved in 34 day-old AMHRCs elicited by 157.4 μM MJ for 18.4 h. The resulting AG yield was 5.5 ± 0.13 mg/g dry weight (DW), which was 2.1-fold higher than that of non-treated control (2.7 ± 0.05 mg/g DW). Moreover, transcriptional analyses revealed that MVD, IDI, FPS and SS were the potential key regulated genes in AG biosynthetic pathway. Overall, this study offered a feasible approach of utilizing MJ elicitation for the enhanced production of valuable AGs in AMHRCs, and also provided a basis for AG biosynthesis via metabolic engineering strategies in the future.
    No preview · Article · Jan 2016
  • Source
    Chang Gao · Na Guo · Na Li · Xiao Peng · Peng Wang · Wei Wang · Meng Luo · Yu-jie Fu
    [Show abstract] [Hide abstract] ABSTRACT: In the present study, antibacterial activity of four kinds of phloroglucinol derivatives extracted from Dryopteris fragrans (L.) Schott against S. aureus, S. epidermidis and P. acnes has been tested. Aspidin BB exerted the strongest antibacterial activity with minimal inhibition concentration (MIC) values ranging from 7.81 to 15.63 μg/mL. The time-kill assay indicated that aspidin BB could kill P. acnes completely at 2 MIC (MBC) within 4 h. By using AFM, we demonstrated extensive cell surface alterations of aspidin BB-treated P. acnes. SDS-PAGE of supernatant proteins and lipid peroxidation results showed that aspidin BB dose-dependently affected membrane permeability of P. acnes. DNA damage and protein degradation of P. acnes were also verified. SDS-PAGE of precipitated proteins revealed possible targets of aspidin BB, i.e., heat shock proteins (26 kDa) and lipase (33 kDa) which could all cause inflammation. Aspidin BB also seriously increased the inhibition rate of lipase activity from 10.20 to 65.20 % to possibly inhibit the inflammation. In conclusions, the effective constituents of D. fragrans (L.) Schott to treat acne might be phloroglucinol derivatives including aspidin BB, aspidin PB, aspidinol and dryofragin. Among this, aspidin BB inhibited the growth of P. acnes by disrupting their membrane, DNA and proteins and finally leaded to the cell death. The obtained data highlighted the potential of using aspidin BB as an alternative treatment for acne vulgaris.
    Preview · Article · Nov 2015 · Archives for Dermatological Research
  • [Show abstract] [Hide abstract] ABSTRACT: In this study, biodiesel was produced from yellow horn seed oil through transesterification using immobilized enzyme Novozym 435 in green deep eutectic solvents (DESs) medium with microwave irradiation method. Eleven DESs were prepared, DES-2 (molar ratio chloride/glycerol 1:2) was proved to be the most effective solvents. Under the optimum conditions, 8% dosage of Novozym 435, methanol/oil ratio 6:1, microwave power 400 W, temperature 50 °C, and reaction time 120 min, 95% conversion yield was achieved. Furthermore, recovered enzymes were used for four successive reaction cycles without any significant loss of enzyme activity. The usage of DES could greatly retain the enzyme activity, increase conversion yield, and make it easy to separate the product. In general, preparation of biodiesel with enzyme in green DESs would be an alternative for traditional transesterification method.
    No preview · Article · Nov 2015 · Journal of Molecular Catalysis B Enzymatic
  • [Show abstract] [Hide abstract] ABSTRACT: A negative pressure cavitation-microwave assisted extraction technique (NMAE) was first applied on extraction of seed oil from yellow horn. The operating conditions were optimized by a Box-Behnken design (BBD) test. Under the optimal conditions, the yield of yellow horn oil seed can reach 52 ± 1%. The extraction kinetics of the NMAE method and soxhlet extraction (SE) method were also investigated. The results indicated that the NMAE method was more effective than the SE method. Therefore, NMAE was an efficient extraction technique for yellow horn seed oil extraction. At last, the extracted oil was used as raw materials for biodiesel production and the main Fatty Acid Methyl Esters contents were analyzed by GC-MS. The conversion yield of biodiesel can reach 96%.
    No preview · Article · Oct 2015 · Fuel
  • [Show abstract] [Hide abstract] ABSTRACT: In this work, Astragalus membranaceus hairy root cultures (AMHRCs) were exposed to ultraviolet radiation (UV-A, UV-B, and UV-C) for promoting isoflavonoid accumulation. The optimum enhancement for isoflavonoid production was achieved in 34-day-old AMHRCs elicited by 86.4 kJ/m(2) of UV-B. The resulting isoflavonoid yield was 533.54 ± 13.61 μg/g dry weight (DW), which was 2.29-fold higher relative to control (232.93 ± 3.08 μg/g DW). UV-B up-regulated the transcriptional expressions of all investigated genes involved in isoflavonoid biosynthetic pathway. PAL and C4H were found to be two potential key genes that controlled isoflavonoid biosynthesis. Moreover, a significant increase was noted in antioxidant activity of extracts from UV-B-elicited AMHRCs (IC50 values = 0.85 and 1.08 mg/mL) in comparison with control (1.38 and 1.71 mg/mL). Overall, this study offered a feasible elicitation strategy to enhance isoflavonoid accumulation in AMHRCs and also provided a basis for metabolic engineering of isoflavonoid biosynthesis in the future.
    No preview · Article · Sep 2015 · Journal of Agricultural and Food Chemistry
  • [Show abstract] [Hide abstract] ABSTRACT: An efficient extraction method, negative-pressure cavitation coupled with aqueous two-phase extraction (NPC-ATPE), was developed to simultaneously extract and enrich flavonoids and stilbenes from pigeon pea leaves. The main bioactive compounds, cajaninstilbene acid (CSA), longistyline C (LLC), pinostrobin (PI) and pinostrobin chalcone (PIC) were chosen as target compounds. The extraction conditions were optimized using central composite design combined with response surface methodology. The optimized conditions were: concentration of (NH4)2SO4 21% (w/w), concentration of ethanol 23% (w/w) and temperature 30°C, negative pressure -0.06MPa, extraction time 30min and the liquid/solid ratio 1:50g/mL. The extraction yields of CSA, PI, PIC and LLC reached 10.25, 5.02, 0.53 and 5.22mg/g, respectively. Furthermore, according to the DPPH, ABTS and FRAP assay, the extracts of NPC-ATPE had significant antioxidant activities with IC 50 value of 0.337mg/mL, TEAC value of 0.151mmol/g and FRAP value of 0.266mmol/g, respectively. The results demonstrated that NPC-ATPE could be an alternative method for natural compounds simultaneous extraction and enrichment in a single step.
    No preview · Article · Sep 2015 · Separation and Purification Technology
  • [Show abstract] [Hide abstract] ABSTRACT: The purpose of the study was to develop a new deep eutectic solvent-based microwave-assisted extraction (DES-MAE) method for extracting the three major active compounds genistin, genistein and apigenin from pigeon pea roots. Optimal conditions for DES-MAE, proposed by the single factor and the Box-Behnken design (BBD) tests, were 30% of water in 1,6-hexanediol/ChCl (7:1, mol/mol) as the extraction solvent, microwave power 600 W, liquid/solid ratio 14 mL/g, temperature 80 °C and time 11 min. The yields of genistin, genistein and apigenin reached 0.449, 0.617 and 0.221 mg/g DW, respectively. The kinetics experiment showed the prominent advantages of DES-MAE such as higher extraction efficiency than other extraction methods. The present results showed that DES could be a kind of green solvent for fast and efficient extraction of the active ingredients from plant materials.
    No preview · Article · Aug 2015 · Separation and Purification Technology
  • [Show abstract] [Hide abstract] ABSTRACT: In the present investigation, the production parameters for the preparation of natto-pigeon pea with immobilized Bacillus natto were optimized and its sensory evaluations were analyzed. The optimal immobilization conditions for Bacillus natto were as follows: alginate concentration 7%, CaCl2 concentration 2.5%, concentration of bacteria 7.4 log cfu/mL and alginate bead diameter 5.0 mm. Fermentation parameters of natto-pigeon pea were optimized by single-factor experiments and central composite design with the index of fibrinolytic activity. The fibrinolytic activity of natto-pigeon pea reached 1895.05 ± 0.24 IU/g under the optimal conditions: wet weight of beads with Bacillus natto 0.8 g/g material, ratio of liquid to solid 15: 1 mL/g, pH 6.5, temperature 38 °C and time 48 h. Moreover, the sensory evaluations of the natto-pigeon pea were superior to that of natto-soybean because of the advantages of pigeon pea on fermentation. Sensory results indicated that the method was an accepted procedure for the production of natto-pigeon pea. Industrial Relevance Fermentation with immobilized microorganisms processing is an emerging technology for the production of functional and safe food with a higher efficiency and quality than conventional solid fermentation. Quantitative data on the fibrinolytic activity and sensory evaluations were essential to demonstrate that the process was indeed safe and efficient. The current work is one of the first to provide such data on natto-pigeon pea with immobilized Bacillus natto, which is of most importance for industrial scale applications as well as agricultural industry.
    No preview · Article · Aug 2015 · Innovative Food Science & Emerging Technologies
  • [Show abstract] [Hide abstract] ABSTRACT: In this study, an accurate method using high pressure liquid chromatography (HPLC) has been established for the simultaneous determination of chlorogenic acid (CA), vitexin-4″-o-glucoside (VG), vitexin-2″-o-rhamnoside (VR), orientoside (ORT), rutin (RT), vitexin (VIT) and hyperoside (HYP) from Crataegus pinnatifida leaves. Box-Behnken design (BBD) combined with response surface methodology (RSM) was used to optimize ultrasound-assisted extraction (UAE) method. Under optimized conditions (temperature 41 ℃, time 31 min, ratio of liquid/solid 15 and ethanol concentration 39%), the yields of CA, VG, VR, ORT, RT, VIT and HYP were 0.46, 0.38, 4.37, 0.033, 0.036, 0.30 and 1.19, mg/g, respectively. Additionally, antioxidant activities of UAE extracts in DPPH radical scavenging (DPPH), ABTS radical scavenging (ABTS) and reducing power tests were determined as 0.69 mg/mL (IC50 value), 0.86 mM Trolox and 0.24 mg/mL (IC50 value), respectively. Compared with conventional maceration extraction (ME) and heat-refluxing extraction (HRE) methods, UAE method showed remarkable advantages in terms of higher extraction yields and better antioxidant activities. Overall, the present results showed that UAE was an efficient and alternative method for the extraction of phenolic compounds form C. pinnatifida leaves and its extracts were potential antioxidant ingredients or additives in food industry with potential preservation properties.
    No preview · Article · Jul 2015 · RSC Advances
  • [Show abstract] [Hide abstract] ABSTRACT: A novel extraction method, homogenate-assisted negative pressure cavitation extraction (HNPCE), was designed for the extraction and determination of main phenolic compounds from Pyrola incarnata Fisch. by LC-MS/MS. The particle sizes and extraction yields in the process of homogenate were compared with conventional pulverization. The results showed that the homogenate under 120 s could produce more suitable particle size powders for analyte extraction. The following NPCE parameters were optimized by a BBD test and under the optimal conditions, the maximum extraction yields of arbutin, epicatechin, hyperin, 2'-O-galloylhyperin and chimaphilin increased 68.7%, 72.0%, 43.3%, 62.5% and 34.5% than the normal NPCE. LC-MS/MS method was successfully applied for the quantification of five target compounds in pyrola, and the results of the precision test indicated a high accuracy of the present method for the quantification of target compounds in pyrola. Furthermore, the antioxidant activities of the pyrola extracts were also determined. The results showed that pyrola had good antioxidant activities and it was a valuable antioxidant natural source.
    No preview · Article · Jul 2015
  • [Show abstract] [Hide abstract] ABSTRACT: Anti-estrogenic therapy is a mainstay for estrogen receptor (ERα)-positive breast cancer. Due to the development of resistance to established anti-hormones such as tamoxifen, novel compounds are required. The low abundant cajanin stilbene acid (CSA) recently isolated by us from Pigeon Pea (Cajanus cajan) has structural similarities with estrogen. We analyzed the cytotoxic and anti-cancer activity of CSA in ERα-positive and –negative human breast cancer cells in vitro, in vivo and in silico. CSA exerts anti-cancer and anti-estrogenic activities towards ERα-positive breast cancer and it showed cytotoxicity towards tamoxifen-resistant MCF-7 cells, implying that CSA may be active against tamoxifen resistant breast cancer cells. CSA showed low cytotoxicity in ERα-negative breast tumor cells as expected. Comparable cytotoxicity was observed towards p53 negative MCF-7 cells, implying that CSA is effective independent of the p53 status. Xenografted MCF-7 cells in nude mice were better inhibited by CSA than by cyclophosphamide. Testing of 8 primary cell cultures derived from human breast cancer biopsies showed that cell cultures from ER-positive tumors were more sensitive than from ER-negative ones. Dose dependent decrease in ERα protein levels was observed upon CSA treatment. Synergistic effect with tamoxifen was observed in terms of increased p53 protein level. CSA affected pathways related to p53, cancer and cell proliferation. Gene promoter analyses supported the ERα regulation. CSA bound to the same site as 17β-estradiol and tamoxifen on ERα. In conclusion, CSA exerts its anticancer effects in ERα-positive breast cancer cells by binding and inhibiting ERα.
    No preview · Article · Jul 2015 · The Journal of nutritional biochemistry
  • [Show abstract] [Hide abstract] ABSTRACT: In this study, novel and green natural deep eutectic solvents (NADESs) as extraction media, are presented for the extraction and determination of phenolics in Cajanus cajan leaves by ultra performance liquid chromatography. Fourteen different NADES systems were investigated for the extraction of phenolics with diverse polarity in C. cajan leaves. Experiments with different extraction solvents and multivariate data analysis demonstrated that the NADES composed of choline chloride and maltose possessed excellent extractability for both polar and weak polar compounds compared to conventional solvents. The influential parameters of microwave-assisted extraction procedure with NADES were examined and optimized. The optimized conditions were as follows: extraction solvent 20% of water in choline chloride/maltose (1/2), extraction temperature 60 oC, liquid/solid ratio 30:1 mL/g and irradiation time 12 min. Moreover, a fast and sensitive UPLC method was firstly developed for the comprehensive analysis of fourteen phenolics in C. cajan leaves. This method was performed within 40 min, and exhibited satisfactory linearity, precision and recovery. These results indicate that the proposed method represents an excellent alternative for the extraction and quantification of phenolics in plant materials.
    No preview · Article · May 2015 · Separation and Purification Technology
  • [Show abstract] [Hide abstract] ABSTRACT: A group of green solvent named polyols-based deep eutectic solvents (PDES) combined with microwave assisted extraction (MAE) was first successfully applied in extracting phenolic compounds from pyrola. A series of PDES with mixing different ratios choline chloride (ChCl) to different polyols were investigated for extraction, and ChCl/1,4-Butanediol (1/4) was found to be the suitable extraction solvent. MAE was more effective than heat-stirring extraction and ultrasonic assisted extraction with PDES. The extraction parameters were optimized by BBD test combined with response surface methodology. The optimal extraction conditions were 30% of water in ChCl/1,4-Butanediol (1/4) at 70 °C for 20 min and liquid/solid ratio 10 mL/g. Moreover, RP-HPLC-UV was developed for the determination of five main active components in pyrola. This method exhibited satisfactory linearity (R2 >0.999), precision (RSD < 4.03%) and recovery (96.17%-103.25%). Sample analysis showed that the contents of hyperin, 2’-O-galloylhyperin, quercitrin, quercetin-O-rhamnoside and chimaphilin in pyrola were 1.627, 4.958, 0.041, 0.089 and 0.349 mg/g, respectively. These results revealed that PDES would be promising green solvents for analytical sample preparation from plant herbs.
    No preview · Article · May 2015 · Separation and Purification Technology
  • Source
    Chunhui Jiang · Lei Gu · Meng Luo · Qing Xu · Hong Zhou
    [Show abstract] [Hide abstract] ABSTRACT: One-third of non-Hodgkin's lymphoma cases are extranodal lymphomas. The gastrointestinal tract is the most common of the extranodal sites. The incidence of primary rectal lymphoma in the gastrointestinal tract is very rare, and its clinical presentation is difficult to distinguish from that of rectal carcinoma. In the treatment of primary rectal lymphomas, surgery options have been controversial. Considering this, we report a case of primary rectal lymphoma (diffuse large B-cell lymphoma) which disappeared completely following cyclophosphamide, hydroxydaunomycin, oncovin and prednisolone chemotherapy. This case demonstrates that systemic chemotherapy may be successful for the primary treatment of rectal lymphoma.
    Full-text · Article · Apr 2015 · Oncology letters
  • [Show abstract] [Hide abstract] ABSTRACT: A new, simple and efficient analysis method for fresh plant in vitro cultures-namely, high-speed homogenization coupled with microwave-assisted extraction (HSH-MAE) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-was developed for simultaneous determination of six alkaloids and eight flavonoids in Isatis tinctoria hairy root cultures (ITHRCs). Compared with traditional methods, the proposed HSH-MAE offers the advantages of easy manipulation, higher efficiency, energy saving, and reduced waste. Cytohistological studies were conducted to clarify the mechanism of HSH-MAE at cellular/tissue levels. Moreover, the established LC-MS/MS method showed excellent linearity, precision, repeatability, and reproducibility. The HSH-MAE-LC-MS/MS method was also successfully applied for screening high-productivity ITHRCs. Overall, this study opened up a new avenue for the direct determination of secondary metabolic profiles from fresh plant in vitro cultures, which is valuable for improving quality control of plant cell/organ cultures and sheds light on the metabolomic analysis of biological samples.
    No preview · Article · Apr 2015 · Analytical and Bioanalytical Chemistry

Publication Stats

1k Citations
333.81 Total Impact Points

Institutions

  • 2014-2016
    • Northeast Forestry University
      • Key Laboratory of Plant Ecology, Ministry of Education
      Charbin, Heilongjiang Sheng, China
    • Shanghai Jiao Tong University
      Shanghai, Shanghai Shi, China
  • 2015
    • Cornell University
      Итак, New York, United States