ResearchSpace
→
Browsing by Author

Browsing by Author "Madala, NE"

Now showing items 1-20 of 20

Analyses of chlorogenic acids and related cinnamic acid derivatives from Nicotiana tabacum tissues with the aid of UPLC-QTOF-MS/MS based on the in-source collision-induced dissociation method

Author: Ncube, EN ; Mhlongo, MI ; Piater, LA ; Steenkamp, PA ; Dubery, IA ; Madala, NE Date: Nov 2014 Chlorogenic acids (CGAs) are a class of phytochemicals that are formed as esters between different derivatives of cinnamic acid and quinic acid molecules. In plants, accumulation of these compounds has been linked to several physiological ... Read more
Biotransformation of isonitrosoacetophenone (2-keto-2-phenyl-acetaldoxime) in tobacco cell suspensions

Author: Madala, NE ; Steenkamp, PA ; Piater, LA ; Dubery, IA Date: Jul 2012 Nicotiana tabacum cell suspensions, 2g wet wt/ml, rapidly took up 1 mM isonitrosoacetophenone (INAP), a plant-derived stress metabolite with anti-oxidative and anti-fungal properties, producing 40-hexopyranosyloxy-30-methoxyisonitrosoacetophenone ... Read more
Chlorogenic acids biosynthesis in Centella asiatica cells is not stimulated by salicylic acid manipulation

Author: Ncube, EN ; Steenkamp, Paul A ; Madala, NE ; Dubery, IA Date: Jul 2016 Exogenous application of synthetic and natural elicitors of plant defence has been shown to result in mass production of secondary metabolites with nutraceuticals properties in cultured cells. In particular, salicylic acid (SA) treatment has ... Read more
Collision energy alteration during mass spectrometric acquisition is essential to ensure unbiased metabolomic analysis

Author: Madala, NE ; Steenkamp, PA ; Piater, LA ; Dubery, IA Date: Aug 2012 Metabolomics entails identification and quantification of all metabolites within a biological system with a given physiological status; as such, it should be unbiased. A variety of techniques are used to measure the metabolite content of ... Read more
Development and optimization of an UPLC-QTOF-MS/MS method based on an in-source collision induced dissociation approach for comprehensive discrimination of chlorogenic acids isomers from Momordica plant species

Author: Madala, NE ; Tugizimana, F ; Steenkamp, PA Date: Sep 2014 Chlorogenic acids (CGA) have been profiled in the leaves of Momordica balsamina, Momordica charantia, and Momordica foetida. All three species were found to contain the trans and cis isomers of 4-acyl para-coumaroylquinic acid (pCoQA), ... Read more
Distribution patterns of flavonoids from three Momordica species by ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry: a metabolomic profiling approach

Author: Madala, NE ; Piater, L ; Dubery, I ; Steenkamp, Paul A Date: Aug 2016 Plants from the Momordica genus, Curcubitaceae, are used for several purposes, especially for their nutritional and medicinal properties. Commonly known as bitter gourds, melon and cucumber, these plants are characterized by a bitter taste ... Read more
Effect of geometrical isomerism of 3,5-dicaffeoylquinic acid on its binding affinity to HIV-integrase enzyme: a molecular docking study

Author: Makola, MM ; Dubery, IA ; Koorsen, G ; Steenkamp, Paul A ; Kabanda, MM ; Du Preez, LL ; Madala, NE Date: 2016 A potent plant-derived HIV-1 inhibitor, 3,5-dicaffeoylquinic acid (diCQA), has been shown to undergo isomerisation upon UV exposure where the naturally occurring, 3(suptrans), 5(suptrans)-diCQA isomer gives rise to the 3(supcis), 5(suptrans)-diCQA, ... Read more c b
The effect of temperature on pressurised hot water extraction of pharmacologically important metabolites as analysed by UPLC-qTOF-MS and PCA

Author: Khoza, BS ; Chimuka, L ; Mukwevho, E ; Steenkamp, PA ; Madala, NE Date: Oct 2014 Metabolite extraction methods have been shown to be a critical consideration for pharmacometabolomics studies and, as such, optimization and development of new extraction methods are crucial. In the current study, an organic solvent-free ... Read more
Identification of hydroxylcinnamoyl tartaric acid esters in Bidens pilosa by UPLC-tandem mass spectrometry

Author: Khoza, BS ; Gbashi, S ; Steenkamp, Paul A ; Njobe, PB ; Madala, NE Date: Mar 2016 Bidens pilosa is a medicinal plant used for the treatment of several physiological illnesses. In South Africa, as the case may be for other African countries, this plant is equally consumed as a vegetable. In the current study, pressurized ... Read more
Influence of the geometric isomers on the radical scavenging properties of 3,5-dica®eoylquinic acid: A DFT study in vacuo and in solution

Author: Makola, MM ; Madala, NE ; Dubery, IA ; Steenkamp, Paul A ; Kabanda, MM Date: Sep 2016 3,5-Dica®eoylquinic acid (diCQA) is a part of the chlorogenic acid group of compounds, largely isolated from food sources and possessing potent antioxidant activity. Only the trans–trans isomer exists in nature, however, abiotic stresses, ... Read more
Metabolomic analysis of isonitrosoacetophenone-induced perturbations in phenolic metabolism of Nicotiana tabacum cells

Author: Madala, NE ; Steenkamp, PA ; Piater, LA ; Dubery, IA Date: Oct 2013 Plants have developed biochemical and molecular responses to adapt to different stress environments. One of the characteristics of the multi-component defence response is the production of defence-related metabolites. Plant defences can be ... Read more
Metabolomic fingerprinting of primed tobacco cells provide the first evidence for the biological origin of cis-chlorogenic acid

Author: Mhlongo, MI ; Piater, LA ; Steenkamp, Paul A ; Madala, NE ; Dubery, IA Date: Jan 2015 Previous studies suggest that only transisomers of chlorogenic acid (CGA) are naturally produced. Cis-isomers have been noted in some plant tissues exposed to different mechanical processes as well as untreated tobacco leaves exposed to ... Read more
Perturbation of pharmacologically relevant polyphenolic compounds in Moringa oleifera against photo-oxidative damages imposed by gamma radiation

Author: Ramabulana, T ; Mavunda, RD ; Steenkamp, Paul A ; Piater, LA ; Dubery, IA ; Madala, NE Date: Mar 2016 Oxidative stress is a physiological state associated with almost all biotic and abiotic stresses in plants. This phenomenon occurs due to imbalances which result from the overproduction of reactive oxygen species (ROS). Plants, however, have ... Read more
Preferential alkali metal adduct formation by cis geometrical isomers of dicaffeoylquinic acids allows for efficient discrimination from their trans isomers during ultra-high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry

Author: Makola, MM ; Steenkamp, Paul A ; Dubery, IA ; Kabanda, MM ; Madala, NE Date: Mar 2016 Caffeoylquinic acid (CQA) derivatives are a group of structurally diverse phytochemicals that have attracted attention due to their many health benefits. The structural diversity of these molecules is due in part to the presence of regio- and ... Read more
Profiling of altered metabolomic states in Nicotiana tabacum cells induced by priming agents

Author: Mhlongo, MI ; Steenkamp, Paul A ; Piater, LA ; Madala, NE ; Dubery, IA Date: Oct 2016 Metabolomics has developed into a valuable tool for advancing our understanding of plant metabolism. Plant innate immune defenses can be activated and enhanced so that, subsequent to being pre-sensitized, plants are able to launch a stronger ... Read more
The short and long of it: shorter chromatographic analysis suffice for sample classification during UHPLC-MS-based metabolic fingerprinting

Author: Madala, NE ; Tugizimana, F ; Steenkamp, PA ; Piater, LA ; Dubery, IA Date: Mar 2013 Ultra high-performance liquid chromatography hyphenated to mass spectrometry (UHPLC-MS) technologies has been widely applied in metabolomics, and the high resolution and peak capacity thereof are only some of the key aspects that are exploited ... Read more
Stimulatory effects of acibenzolar-s-methyl on chlorogenic acids biosynthesis in Centella asiatica cells

Author: Ncube, EN ; Steenkamp, Paul A ; Madala, NE ; Dubery, IA Date: Sep 2016 Centella asiatica is a perrenial herb that grows in tropical regions with numerous medicinal properties mostly attributed to the presence of pentacyclic triterpenoids. Interestingly, this plant also possess a significant amount of ... Read more
Untargeted metabolomics analysis reveals dynamic changes in azelaic acid- and salicylic acid derivatives in LPS-treated Nicotiana tabacum cells

Author: Mhlongo, MI ; Tugizimana, F ; Piater, LA ; Steenkamp, Paul A ; Madala, NE ; Dubery, IA Date: Jan 2017 To counteract biotic stress factors, plants employ multilayered defense mechanisms responsive to pathogen-derived elicitor molecules, and regulated by different phytohormones and signaling molecules. Here, lipopolysaccharide (LPS), a ... Read more
UPLC-qTOF-MS profiling of pharmacologically important chlorogenic acids and associated glycosides in Moringa ovalifolia leaf extracts

Author: Makita, C ; Chimuka, L ; Cukrowska, E ; Steenkamp, PA ; Kandawa-Schutz, M ; Ndhlala, AR ; Madala, NE Date: Jan 2017 Moringa ovalifolia Dinter & A. Berger (Moringaceae) is a succulent-stemmed plant, endemic to the desert and semi-desert areas of central Namibia and southwestern Angola. Just like other species in the Moringaceae family, M. ovalifolia is ... Read more
Variation in pharmacologically potent rutinoside-bearing flavonoids amongst twelve Moringa oleifera Lam. cultivars

Author: Makita, C ; Madala, NE ; Cukrowska, A ; Abdelgadir, H ; Chimuka, L ; Steenkamp, Paul A ; Ndhlala, AR Date: Sep 2017 Recent evidence has shown that consumption of plants rich in phenolic compounds has health-promoting benefits. Amongst these plants, include Moringa oleifera Lam. (Moringaceae) which has gained significant attention due to its high contingency ... Read more

Now showing items 1-20 of 20

Browse

All of ResearchSpace

Quick Links

Legislation and compliance

General Enquiries

Tel: + 27 12 841 2911
Email: callcentre@csir.co.za

Physical Address
Meiring Naudé Road
Brummeria
Pretoria
South Africa

Postal Address
PO Box 395
Pretoria 0001
South Africa

Social Connect

Copyright © CSIR 2017. All Rights Reserved

Resources on this site are free to download and reuse according to associated licensing provision. Please read the terms and conditions of usage of each resource.