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Bao Yang - One of the best experts on this subject based on the ideXlab platform.
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INVESTIGATION OF SUPERCRITICAL FLUID EXTRACTION OF PUERARIN FROM PUERARIA Lobata
Journal of Food Process Engineering, 2009Co-Authors: Lingzhao Wang, Bao YangAbstract:Puerarin, which is the most abundant isoflavone in Pueraria Lobata, has many pharmacological effects. In this study, supercritical carbon dioxide extraction was employed as a novel and efficient technique to extract puerarin from Pueraria Lobata. Effects of four variables (pressure, temperature, time and co-solvent amount) on the puerarin yield of Pueraria Lobata were investigated. Up to a certain value, the puerarin yield increased with increasing pressure; thereafter, puerarin yield decreased as pressure increased. A similar effect of temperature was also found. When the temperature was at 50C or the pressure was at 20 MPa, the highest puerarin yield obtained was 5.8 ± 0.3 mg/g. Positive effects of time and co-solvent amount were observed on the puerarin yield. However, when the time was longer than 100 min or the co-solvent amount was greater than 120 g, no significant improvement was detected in the puerarin yield. It was therefore important to define the level of each variable for an efficient preparation of puerarin. From the results obtained, supercritical carbon dioxide extraction was proved to be an efficient technique for extraction of puerarin from Pueraria Lobata. PRACTICAL APPLICATIONS Pueraria Lobata is a famous Chinese traditional medicinal herb which has been consumed by many people all over the world. Puerarin is the most abundant isoflavone in this herb, and it has been proven to have some important pharmacological properties. In this study, a novel technique called supercritical carbon dioxide extraction was employed to prepare puerarin from Pueraria Lobata. Effects of pressure, temperature, time and co-solvent amount on the puerarin yield were evaluated. The results were helpful in understanding the extraction process of puerarin and could give evidence for further developments on this special medicinal herb.
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Optimisation of supercritical fluid extraction of flavonoids from Pueraria Lobata.
Food chemistry, 2007Co-Authors: Lingzhao Wang, Bao YangAbstract:Abstract Supercritical carbon dioxide extraction was employed to extract flavonoids from Pueraria Lobata. The optimal conditions for flavonoid extraction were determined by response surface methodology. Box–Behnken design was applied to evaluate the effects of three independent variables (pressure, temperature and co-solvent amount) on the flavonoid yield of P. Lobata. Correlation analysis of the mathematical-regression model indicated that a quadratic polynomial model could be employed to optimise the supercritical carbon dioxide extraction of flavonoids. From response surface plots, pressure, temperature and co-solvent amount exhibited independent and interactive effects on the extraction of flavonoids. The optimal conditions to obtain the highest flavonoid yield of P. Lobata were a pressure of 20.04 MPa, a temperature of 50.24 °C and a co-solvent amount of 181.24 ml. Under these optimal conditions, the experimental values agreed with the predicted values, using analysis of variance, indicating a high goodness of fit of the model used and the success of response surface methodology for optimising supercritical carbon dioxide extraction of flavonoids from P. Lobata.
Mohammad Shorif Uddin - One of the best experts on this subject based on the ideXlab platform.
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A revision on Urena Lobata L.
International Journal of Medicine, 2017Co-Authors: Muhammad Torequl Islam, Mohammad Shorif UddinAbstract:The medicinal plant, Urena Lobata L. (Malvaceae) is commonly known as aramina fibre, caesarweed or congo jute is widely distributed in Bangladesh. The ethnopharmacological usages of the parts of this plant are antique for the treatment of various diseases. In the recent years, a number of scientific evidences have been seen on its isolated phytochemicals and biological activities. This review offers a current scenario of the U. Lobata , emphasized on the phyto-pharmacological findings. A search was made in the electronic databases such as PubMed, Science Direct and Google scholar for the published articles till January 31, 2017. To date, several important flavonoids, glycosides and terpenoids have been isolated from this plant. U. Lobata possesses promising biological activities, including antioxidant, inflammatory, antimicrobial, anticancer, anti-diarrheal, anti-diabetic, anti-hyperlipidemic, neuropharmacological etc. U. Lobata may be one of the good sources of therapeutic phytochemicals.
Kwok-pui Fung - One of the best experts on this subject based on the ideXlab platform.
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A comparative study on aqueous root extracts of Pueraria thomsonii and Pueraria Lobata by antioxidant assay and HPLC fingerprint analysis.
Journal of Ethnopharmacology, 2004Co-Authors: Ren-wang Jiang, Kit-man Lau, Hung-ming Lam, Wing-sze Yam, Lai-kin Leung, Kam-lin Choi, Mary M.y. Waye, Thomas C. W. Mak, Kamsang Woo, Kwok-pui FungAbstract:The roots of Pueraria thomsonii and Pueraria Lobata are officially recorded in Chinese Pharmacopoeia under the same name Radix Puerariae. However, the aqueous root extract of Pueraria Lobata showed more potent antioxidant activity than that of Pueraria thomsonii. A qualitative HPLC method was developed to compare the chemical profiles of Pueraria thomsonii and Pueraria Lobata, which revealed four major common peaks (daidzein 1, daidzin 2, puerarin 3 and 5-hydroxypuerarin 4) and two major different peaks (3-hydroxypuerarin 5 and 3'-methoxypuerarin 6) in their chromatograms. Semi-quantitative analysis showed that the contents of 1-3 in Pueraria Lobata are about three, three, and five times higher than those of Pueraria thomsonii, respectively. The higher contents of isoflavonoids in Pueraria Lobata were inferred to be responsible for its more potent antioxidant activity as compared with that of Pueraria thomsonii. The HPLC method developed in this study and chemical markers 1-6 can be used for the rapid identification and evaluation of Radix Puerariae herbs and their aqueous supplements, and the results of this investigation support the use of Pueraria Lobata and Pueraria thomsonii in the clinic application and as dietary supplement, respectively.
Lingzhao Wang - One of the best experts on this subject based on the ideXlab platform.
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INVESTIGATION OF SUPERCRITICAL FLUID EXTRACTION OF PUERARIN FROM PUERARIA Lobata
Journal of Food Process Engineering, 2009Co-Authors: Lingzhao Wang, Bao YangAbstract:Puerarin, which is the most abundant isoflavone in Pueraria Lobata, has many pharmacological effects. In this study, supercritical carbon dioxide extraction was employed as a novel and efficient technique to extract puerarin from Pueraria Lobata. Effects of four variables (pressure, temperature, time and co-solvent amount) on the puerarin yield of Pueraria Lobata were investigated. Up to a certain value, the puerarin yield increased with increasing pressure; thereafter, puerarin yield decreased as pressure increased. A similar effect of temperature was also found. When the temperature was at 50C or the pressure was at 20 MPa, the highest puerarin yield obtained was 5.8 ± 0.3 mg/g. Positive effects of time and co-solvent amount were observed on the puerarin yield. However, when the time was longer than 100 min or the co-solvent amount was greater than 120 g, no significant improvement was detected in the puerarin yield. It was therefore important to define the level of each variable for an efficient preparation of puerarin. From the results obtained, supercritical carbon dioxide extraction was proved to be an efficient technique for extraction of puerarin from Pueraria Lobata. PRACTICAL APPLICATIONS Pueraria Lobata is a famous Chinese traditional medicinal herb which has been consumed by many people all over the world. Puerarin is the most abundant isoflavone in this herb, and it has been proven to have some important pharmacological properties. In this study, a novel technique called supercritical carbon dioxide extraction was employed to prepare puerarin from Pueraria Lobata. Effects of pressure, temperature, time and co-solvent amount on the puerarin yield were evaluated. The results were helpful in understanding the extraction process of puerarin and could give evidence for further developments on this special medicinal herb.
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Optimisation of supercritical fluid extraction of flavonoids from Pueraria Lobata.
Food chemistry, 2007Co-Authors: Lingzhao Wang, Bao YangAbstract:Abstract Supercritical carbon dioxide extraction was employed to extract flavonoids from Pueraria Lobata. The optimal conditions for flavonoid extraction were determined by response surface methodology. Box–Behnken design was applied to evaluate the effects of three independent variables (pressure, temperature and co-solvent amount) on the flavonoid yield of P. Lobata. Correlation analysis of the mathematical-regression model indicated that a quadratic polynomial model could be employed to optimise the supercritical carbon dioxide extraction of flavonoids. From response surface plots, pressure, temperature and co-solvent amount exhibited independent and interactive effects on the extraction of flavonoids. The optimal conditions to obtain the highest flavonoid yield of P. Lobata were a pressure of 20.04 MPa, a temperature of 50.24 °C and a co-solvent amount of 181.24 ml. Under these optimal conditions, the experimental values agreed with the predicted values, using analysis of variance, indicating a high goodness of fit of the model used and the success of response surface methodology for optimising supercritical carbon dioxide extraction of flavonoids from P. Lobata.
Peter E Smouse - One of the best experts on this subject based on the ideXlab platform.
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foraging patterns of acorn woodpeckers melanerpes formicivorus on valley oak quercus Lobata nee in two california oak savanna woodlands
Oecologia, 2011Co-Authors: Douglas G Scofield, Walter D Koenig, Victor Ryan Alfaro, Victoria L Sork, Delphine Grivet, Edith Martinez Martinez, Jeannette Papp, Andrea R Pluess, Peter E SmouseAbstract:Landscape characteristics and social behavior can affect the foraging patterns of seed-dependent animals. We examine the movement of acorns from valley oak (Quercus Lobata) trees to granaries maintained by acorn woodpeckers (Melanerpes formicivorus) in two California oak savanna-woodlands differing in the distribution of Q. Lobata within each site. In 2004, we sampled Q. Lobata acorns from 16 granaries at Sedgwick Reserve in Santa Barbara County and 18 granaries at Hastings Reserve in Monterey County. Sedgwick has lower site-wide density of Q. Lobata than Hastings as well as different frequencies of other Quercus species common to both sites. We found acorn woodpeckers foraged from fewer Q. Lobata seed source trees (K g = 4.1 ± 0.5) at Sedgwick than at Hastings (K g = 7.6 ± 0.6) and from fewer effective seed sources (N em* = 2.00 and 5.78, respectively). The differences between sites are due to a greater number of incidental seed sources used per granary at Hastings than at Sedgwick. We also found very low levels of seed source sharing between adjacent granaries, indicating that territoriality is strong at both sites and that each social group forages on its own subset of trees. We discovered an interesting spatial pattern in the location of granaries. At Sedgwick, acorn woodpeckers situated their granaries within areas of higher-than-average tree density, while at Hastings, they placed them within areas of lower-than-average tree density, with the outcome that granaries at the two sites were located in areas of similar valley oak density. Our results illustrate that landscape characteristics might influence the number of trees visited by acorn woodpeckers and the locations of territories, while woodpecker social behavior, such as territoriality, shapes which trees are visited and whether they are shared with other social groups.