Ifat Parveen

Isolation, identification and quantitation of hydroxycinnamic acid conjugates, potential platform chemicals, in the leaves and stems of Miscanthus × giganteus using LC–ESI-MSn

Miscanthus×giganteus is a source of platform chemicals and bioethanol through fermentation. Cinnamates in leaves and stems were analysed by LC-ESI-MS(n). Free phenols were extracted and separated chromatographically. More than 20 hydroxycinnamates were identified by UV and LC-ESI-MS(n). Comparative LC-MS studies on the leaf extract showed isomers of O-caffeoylquinic acid (3-CQA, 4-CQA and 5-CQA), O-feruloylquinic acid (3-FQA, 4-FQA and 5-FQA) and para-coumaroylquinic acid (3-pCoQA and 5-pCoQA). Excepting 3-pCoQA, all were also detected in stem. 5-CQA dominated in leaf; a mandelonitrile-caffeoylquinic acid dominated in stem. Three minor leaf components were distinguished by fragmentation patterns in a targetted MS(2) experiment as dicaffeoylquinic acid isomers. Others (M(r) 516) were tentatively identified as hexosylcaffeoyl-quinates. Three positional isomers of O-caffeoylshikimic acid were minor components. p-Hydroxybenzaldehyde was also a major component in stem. This is the first report of the hydroxycinnamic acid profile of leaves and stems of M.×giganteus.

Extraction, structural characterisation and evaluation of hydroxycinnamate esters of orchard grass (Dactylis glomerata) as substrates for polyphenol oxidase

Polyphenol oxidase (PPO) activity has been reported in orchard grass (Dactylis glomerata); however, to date, no endogenous substrates have been identified. In the present study, we report the isolation and structural elucidation of PPO substrates in this species. The free phenol fraction was extracted, separated by reverse-phase chromatography and six potential substrates, including two hydroxycinnamate esters, were identified by UV spectrometry, electrospray ionisation-tandem mass spectrometry (LC-ESI-MS(n)) and 1D and 2D NMR analyses ((1)H NMR, (13)C NMR, DEPT, COSY, HMQC and HMBC). Furthermore, three caffeoylquinic acids (3-CQA, 4-CQA and 5-CQA) were identified by comparison of their spectral data (ESI-MS) with those of known compounds and literature data. Five of these compounds were demonstrated to be substrates for orchard grass PPO.

Potential sources of high value chemicals from leaves, stems and flowers of Miscanthus sinensis ‘Goliath’ and Miscanthus sacchariflorus

Society demands chemicals from sustainable sources. Identification of commercially important chemicals in crops increases value in biorefineries and reduces reliance on petrochemicals. Miscanthus sinensis and Miscanthus sacchariflorus are high-yielding distinct plants, which are sources of high-value chemicals and bioethanol through fermentation. Cinnamates in leaves, stems and flowers were analysed by LC-ESI-MS(n). Free phenols were extracted and separated chromatographically. More than twenty hydroxycinnamates were identified by UV and LC-ESI-MS(n). Several cinnamate hexosides were detected in the M. sinensis flower and in M. sacchariflorus (leaf and stem). Hydroxybenzoic acids and their hexosides were observed in leaf and stem of M. sacchariflorus. Higher concentrations of 3-feruloylquinic acid were observed in M. sacchariflorus stem, suggesting a role in cell-wall biosynthesis. This technique can be used to screen plants in a mapping family to identify genotypes/species with high concentrations of phenols. Plants with low concentrations of antimicrobial phenols may be good feedstocks for fermentation.

A Metagenomics Approach to Evaluate the Impact of Dietary Supplementation with Ascophyllum nodosum or Laminaria digitata on Rumen Function in Rusitec Fermenters

There is an increasing need to identify alternative feeds for livestock that do not compete with foods for humans. Seaweed might provide such a resource, but there is limited information available on its value as an animal feed. Here we use a multi-omics approach to investigate the value of two brown seaweeds, Ascophyllum nodosum (ASC) and Laminaria digitata (LAM), as alternative feeds for ruminants. These seaweeds were supplemented at 5% inclusion rate into a control diet (CON) in a rumen simulation fermenter. The seaweeds had no substantial effect on rumen fermentation, feed degradability or methane emissions. Concentrations of total bacteria, anaerobic fungi, biodiversity indices and abundances of the main bacterial and methanogen genera were also unaffected. However, species-specific effects of brown seaweed on the rumen function were noted: ASC promoted a substantial decrease in N degradability (−24%) due to its high phlorotannins content. Canonical correspondence analysis of the bacterial community revealed that low N availability led to a change in the structure of the bacterial community. ASC also decreased the concentration of Escherichia coli O157:H7 post-inoculation. In contrast, LAM which has a much lower phlorotannin content did not cause detrimental effects on N degradability nor modified the structure of the bacterial community in comparison to CON. This adaptation of the microbial community to LAM diets led to a greater microbial ability to digest xylan (+70%) and carboxy-methyl-cellulose (+41%). These differences among brown seaweeds resulted in greater microbial protein synthesis (+15%) and non-ammonia N flow (+11%) in LAM than in ASC diets and thus should led to a greater amino acid supply to the intestine of the animal. In conclusion, it was demonstrated that incorporation of brown seaweed into the diet can be considered as a suitable nutritional strategy for ruminants; however, special care must be taken with those seaweeds with high phlorotannin concentrations to prevent detrimental effects on N metabolism. This study highlights the value of combining fermentation and enzyme activity data with molecular characterization of the rumen microbiome in evaluating novel feeds for ruminants. Further experiments are required to determine the maximum seaweed inclusion rate tolerated by rumen microbes.

Neoclerodane Diterpenoids from Reehal Fatima, Teucrium yemense

Teucrium yemense (Defl), locally known as Reehal Fatima, is a medicinal plant commonly grown in Saudi Arabia and Yemen. Phytochemical investigation of the aerial parts of T. yemense yielded six new neoclerodane diterpenoids, namely fatimanol A-E (1, 2, 3, 5, and 6) and fatimanone (4), and the known teulepicephin (7). As both the Teucrium genus and the related Lamiaceae family have previously been widely reported to possess anthelmintic and antimicrobial activities, the structural and biological characterization of the seven diterpenoids was pursued. The structures of the new compounds were elucidated from their 2D NMR and MS profiles and by comparison to related compounds. The structure of fatimanol D (5) was confirmed by X-ray crystallographic analysis. The new structures contribute to the breadth of knowledge of secondary metabolites in this genus.

Anti-inflammatory properties of an extract of M. ilicifolia in the human intestinal epithelial Caco-2 cell line

ETHNOPHARMACOLOGY RELEVANCE Maytenus ilicifolia is a Celastracea plant used in traditional medicine to alleviate digestive tract inflammatory disorders. AIM OF THE STUDY We investigated anti-inflammatory properties of M. ilicifolia crude extract towards Caco-2 cell line, as a model of Toll-like Receptor 2 (TLR-2) inflammatory pathway. MATERIALS AND METHODS Toxicity was assessed following culture of Caco-2 with M. ilicifolia, using apparent cell permeability and trans-epithelial electric resistance. Anti-inflammatory properties of M. ilicifolia were assessed through IL-8 secretion and TLR-2 associated gene expression of Caco-2 cells with or without an LTA challenge. RESULTS M. ilicifolia was not toxic to Caco-2 cells. M. ilicifolia down-regulated TLR2 expression with and without LTA challenge but had no effect on other genes. Following LTA challenge of Caco-2 cells, 100 and 200µg/mL M. ilicifolia abrogated IL-8 secretion. CONCLUSIONS We provide preliminary data for some M. ilicifolia anti-inflammatory properties. Further research must establish the full extent and mode of action on particular inflammatory pathways.

Relationship between grazing lamb growth rate and blood plasma analytes as profiled by gas chromatography with time-of-flight mass spectrometry (GC-TOF/MS).

There can be considerable variation in the performance of individual lambs grazing on the same pasture. Gas chromatography with time-of-flight mass spectrometry (GC-TOF/MS) was used to profile the relative abundances of metabolites in plasma from growing lambs to determine any correlation effects between plasma metabolites and liveweight gain. Analysis of relative abundance of 336 analyte clusters and liveweight gain revealed that the growth rates of female lambs were significantly positively correlated with 5 analyte clusters and negatively correlated with 5 other analyte clusters. Growth rates of male lambs were likewise significantly positively correlated with 9 analyte clusters and negatively with 5 analyte clusters. Analytes identified as being associated with lamb growth rate included the amino acids valine, methionine, phenylalanine, cystine and asparagine, and oxalic acid, phenylacetic acid, and phosphoric acid. A number of currently unidentified analytes were significantly correlated with growth rate. Stepwise regression of the analytes on lamb growth rate yielded relationships that accounted for 48% and 58% of the variation in female and male lamb growth rates, respectively. This study demonstrated that by using GC-TOF/MS in combination with multivariate statistical techniques it is possible to correlate the presence of specific analytes in sheep plasma with growth rate.