scispace - formally typeset
Search or ask a question
Author

Nianbai Fang

Bio: Nianbai Fang is an academic researcher from University of Arkansas for Medical Sciences. The author has contributed to research in topics: Ageratina & Astereae. The author has an hindex of 22, co-authored 56 publications receiving 1977 citations. Previous affiliations of Nianbai Fang include Anhui University & University of California, Berkeley.


Papers
More filters
Journal ArticleDOI
TL;DR: The diagnostic fragmentation patterns of different phenolics are presented on the basis of electrospray ionization (ESI) MS/MS data of components in dried plums and fourteen authentic standards.
Abstract: Dried plums are known as a healthy food in the West and used as medicine in India. They have been characterized by high concentrations of phenolic compounds, which are believed to play a crucial role in protection against various age-related diseases. Liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) with four different conditions was used to analyze the phytochemicals in commercial dried plums. The major components were neochlorogenic acid and cryptochlorogenic acid. Forty minor components were characterized by their MS/MS spectra and LC retention time. Six of them are novel ester isomers formed by two caffeic acids and one quinic acid. The diagnostic fragmentation patterns of different phenolics are presented on the basis of electrospray ionization (ESI) MS/MS data of components in dried plums and fourteen authentic standards. Keywords: Dried plums; Prunus domestica; hydroxycinnamic acids; chlorogenic acid isomers; LC/MS/MS; MS diagnostic fragmentation pattern

308 citations

Journal ArticleDOI
TL;DR: There were significant interspecies differences in isoflavone metabolism, and the overall metabolic profile of pigs was closer to that of women than that of rats or monkeys.
Abstract: Various physiologic effects of soy food consumption have been attributed to the estrogenic actions of isoflavones. The order of estrogen receptor binding potency of soy-derived isoflavone aglycones is equol > genistein > daidzein, and their conjugates are less potent. Because the metabolic profile may be an important determinant of bioactivity after soy intake, we studied the serum and urine isoflavone concentrations in 3 animal models and compared them with isoflavone profiles in women. Female Sprague-Dawley rats, Hampshire/Duroc Cross pigs, cynomolgus monkeys, and women were fed diets containing soy protein isolate. Isoflavones and their metabolites were measured by LC-MS or electrochemical detection. Equol represented approximately 77 and 52% (molar ratio) of summed serum isoflavones (isoflavones plus metabolites) in rats and cynomolgus monkeys, respectively. Equol was undetectable in pig serum and human plasma, but daidzein and genistein contributed >88% of summed circulating isoflavones. Monkey and rat urine contained high levels of aglycones (>85% and >32%, respectively), whereas pigs and women excreted isoflavone mainly in the form of glucuronides (>80%), with <10% as aglycones. Isoflavones in human plasma were predominantly glucuronides (75%) with 24% as sulfates and <1% as aglycones; in monkey serum, however, 64% of isoflavones were sulfates, 30% glucuronides, and 6% aglycones. Equol was also a major serum metabolite of 6-mo-old rhesus monkeys (80% of summed isoflavones). Thus, there were significant interspecies differences in isoflavone metabolism, and the overall metabolic profile of pigs was closer to that of women than that of rats or monkeys.

187 citations

Journal ArticleDOI
TL;DR: Findings on cubé insecticide constituents and an earlier study comparing rotenone and pyridaben miticide indicate that inhibition of NADH:ubiquinone oxidoreductase activity lowers the level of induced ODC activity leading to the antiproliferative effect and anticancer action.
Abstract: Rotenone and rotenoid-containing botanicals, important insecticides and fish poisons, are reported to have anticancer activity in rats and mice. The toxic action of rotenone is attributed to inhibition of NADH:ubiquinone oxidoreductase activity and the purported cancer chemopreventive effect of deguelin analogs has been associated with inhibition of phorbol ester-induced ornithine decarboxylase (ODC) activity. This study defines a possible relationship between these two types of activity important in evaluating the toxicology of rotenoid pesticides and the suitability of the anticancer model. Fractionation of cube resin (the commercial rotenoid pesticide) establishes that the activity in both assays is due primarily to rotenone (IC50 = 0.8–4 nM), secondarily to deguelin, and in small part to rotenolone and tephrosin. In addition, the potency of 29 rotenoids from cube insecticide for inhibiting NADH:ubiquinone oxidoreductase in vitro assayed with bovine heart electron transport particles satisfactorily predicts their potency in vivo in the induced ODC assay using noncytotoxic rotenoid concentrations with cultured MCF-7 human breast cancer cells (r = 0.86). Clearly the molecular features of rotenoids essential for inhibiting NADH:ubiquinone oxidoreductase are similar to those for blocking ODC induction. This apparent correlation extends to 11 flavonoids and stilbenoids from cube resin (r = 0.98) and genistein and resveratrol except for lower potency and less selectivity than the rotenoids relative to cytotoxicity. These findings on cube insecticide constituents and our earlier study comparing rotenone and pyridaben miticide indicate that inhibition of NADH:ubiquinone oxidoreductase activity lowers the level of induced ODC activity leading to the antiproliferative effect and anticancer action.

169 citations

Journal ArticleDOI
TL;DR: Assays of the 29 rotenoids as inhibitors of NADH:ubiquinone oxidoreductase activity and phorbol ester-induced ornithine decarboxylase activity for cytotoxicity establish similar structure-activity relationships in each system and the importance of the overall molecular conformation and the E-ring substituents.
Abstract: Cube resin, the root extract from Lonchocarpus utilis and urucu, is an important insecticide, acaricide, and piscicide. The four major active ingredients are rotenone, deguelin, rotenolone, and tep...

107 citations

Journal ArticleDOI
TL;DR: Nine new relatively polar triterpene alcohol and sterol esters were characterized by their retention behaviors in LC and ESI-MS data from both negative- and positive-ion mode, providing the first evidence for the presence of hydroxylated ferulate esters and caffeate esters as part of gamma-oryzanol in rice bran.
Abstract: Ferulic acid esters of triterpene alcohols and sterols in rice bran oil have been extensively studied and reported to possess important pharmacological actions. Inconsistent results on the numbers and structures of ferulates have been reported, primarily because of the analytical procedures employed. Conventional methods for analysis of phytosterol content in oil are carried out by characterization of trimethylsilylated derivatives (TMS) using GC-EI-MS after saponification of oils or individual compound isolated from oils. This study developed an LC-MS/MS method for the direct analysis of triterpene alcohol and sterol esters in rice bran oil. In addition to verifying the results of previous research, nine new relatively polar triterpene alcohol and sterol esters were characterized by their retention behaviors in LC and ESI-MS data from both negative- and positive-ion mode. This is the first evidence for the presence of hydroxylated ferulate esters and caffeate esters as part of gamma-oryzanol in rice bran. The method enables rapid and direct on-line characterization of triterpene alcohol and sterol esters in oils. LC-MS/MS equipped with reverse-phase LC and ESI-MS should be well-suited for identification and quantification of the polar metabolites of phytosterols in biological fluids after consumption of rice bran oil or other oils.

101 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: In the context of agricultural pest management, botanical insecticides are best suited for use in organic food production in industrialized countries but can play a much greater role in the production and postharvest protection of food in developing countries.
Abstract: Botanical insecticides have long been touted as attractive alternatives to synthetic chemical insecticides for pest management because botanicals reputedly pose little threat to the environment or to human health. The body of scientific literature documenting bioactivity of plant derivatives to arthropod pests continues to expand, yet only a handful of botanicals are currently used in agriculture in the industrialized world, and there are few prospects for commercial development of new botanical products. Pyrethrum and neem are well established commercially, pesticides based on plant essential oils have recently entered the marketplace, and the use of rotenone appears to be waning. A number of plant substances have been considered for use as insect antifeedants or repellents, but apart from some natural mosquito repellents, little commercial success has ensued for plant substances that modify arthropod behavior. Several factors appear to limit the success of botanicals, most notably regulatory barriers and the availability of competing products (newer synthetics, fermentation products, microbials) that are cost-effective and relatively safe compared with their predecessors. In the context of agricultural pest management, botanical insecticides are best suited for use in organic food production in industrialized countries but can play a much greater role in the production and postharvest protection of food in developing countries.

2,996 citations

Journal ArticleDOI
TL;DR: Privileged substructures are believed to achieve this through the mimicry of common protein surface elements that are responsible for binding, such as β- and gamma;-turns.
Abstract: Privileged substructures are of potentially great importance in medicinal chemistry. These scaffolds are characterized by their ability to promiscuously bind to a multitude of receptors through a variety of favorable characteristics. This may include presentation of their substituents in a spatially defined manner and perhaps also the ability to directly bind to the receptor itself, as well as exhibiting promising characteristics to aid bioavailability of the overall molecule. It is believed that some privileged substructures achieve this through the mimicry of common protein surface elements that are responsible for binding, such as β- and gamma;-turns. As a result, these structures represent a promising means by which new lead compounds may be identified.

2,620 citations

Journal ArticleDOI
TL;DR: Flavonoids are plant pigments that are synthesised from phenylalanine, generally display marvelous colors known from flower petals, mostly emit brilliant fluorescence when they are excited by UV light, and are ubiquitous to green plant cells.

2,424 citations

Journal ArticleDOI
TL;DR: This document reviews various plant feedstuis, which currently are or potentially may be incorporated into aquafeeds to support the sustainable production of various ¢sh species in aquaculture and strategies and techniques to optimize the nutritional composition and limit potentially adverse eiects of bioactive compounds are described.
Abstract: Continued growth and intensi¢cation of aquaculture production depends upon the development of sustainable protein sources to replace ¢sh meal in aquafeeds. This document reviews various plant feedstuis, which currently are or potentially may be incorporated into aquafeeds to support the sustainable production of various ¢sh species in aquaculture. The plant feedstuis considered include oilseeds, legumes and cereal grains, which traditionally have been used as protein or energy concentrates as well as novel products developed through various processing technologies. The nutritional composition of these various feedstuis are considered along with the presence of any bioactive compounds that may positively or negatively aiect the target organism. Lipid composition of these feedstuis is not speci¢cally considered although it is recognized that incorporating lipid supplements in aquafeeds to achieve proper fatty acid pro¢les to meet the metabolic requirements of ¢sh and maximize human health bene¢ts are important aspects. Speci¢c strategies and techniques to optimize the nutritional composition of plant feedstuis and limit potentially adverse eiects of bioactive compounds are also described. Such information will provide a foundation for developing strategic research plans for increasing the use of plant feedstuis in aquaculture to reduce dependence of animal feedstuis and thereby enhance the sustainability of aquaculture.

1,910 citations

Journal ArticleDOI
TL;DR: This review summarizes the chemistry, biosynthesis and occurrence of the compounds involved, namely the C6-C3-C6 flavonoids-anthocyanins, dihydrochalcones, Flavan-3-ols, flavanones, flavones, Flavonols and isoflavones, and the mechanisms underlying these processes are discussed.

1,728 citations