Suresh Govindaraghavan - Academia.edu (original) (raw)
Uploads
Papers by Suresh Govindaraghavan
International Journal of Molecular Sciences
Identification of bioactive natural products from plants starts with the screening of extracts fo... more Identification of bioactive natural products from plants starts with the screening of extracts for a desired bioactivity such as antimicrobial, antifungal, anti-cancer, anti-inflammatory, or neuroprotective. When the bioactivity shows sufficient potency, the plant material is subjected to bio-activity-guided fractionation, which involves, e.g., sequential extraction followed by chromatographic separation, including HPLC. The bioactive compounds are then structurally identified by high-resolution mass spectrometry and nuclear magnetic resonance (NMR). One of the questions that come up during the purification process is how much of the bioactivity originally present in the crude extract is preserved during the purification process. If this is the case, it is interesting to investigate if the loss of total bioactivity is caused by the loss of material during purification or by the degradation or evaporation of potent compounds. A further possibility would be the loss of synergy between...
Journal of Agricultural and Food Chemistry, 2002
Fitoterapia, 2000
Natural tetranortriterpenoids such as cedrelone from Toona ciliata, azadiradione from Azadirachta... more Natural tetranortriterpenoids such as cedrelone from Toona ciliata, azadiradione from Azadirachta indica, limonin, limonol and nomilinic acid from Citrus medica, along with some cedrelone derivatives were tested for their antifungal activity against Puccinia arachidis, a groundnut rust pathogen. Results show that cedrelone was the most effective in reducing rust pustule emergence. Replacement of functional groups or modification of the A or the B ring in cedrelone reduced the effectiveness indicating the importance of specific structural features for activity.
BMC Genomics, 2013
Background Pattern-oriented chemical profiling is increasingly being used to characterize the phy... more Background Pattern-oriented chemical profiling is increasingly being used to characterize the phytochemical composition of herbal medicines for quality control purposes. Ideally, a fingerprint of the biological effects should complement the chemical fingerprint. For ethical and practical reasons it is not possible to test each herbal extract in laboratory animals or humans. What is needed is a test system consisting of an organism with relevant biology and complexity that can serve as a surrogate in vitro system. The purpose of this study was to test the hypothesis that the Saccharomyces cerevisiae transcriptome might be used as an indicator of phytochemical variation of closely-related yet distinctly different extracts prepared from a single species of a phytogeographically widely distributed medicinal plant. We combined phytochemical profiling using chromatographic methods (HPTLC, HPLC-PDA-MS/MS) and gene expression studies using Affymetrix Yeast 2.0 gene chip with principal compo...
Phytoparasitica, 1998
Evaluation of the actwity of the cold expeller neem oil (Azadirachta indica A. Juss.) and the fra... more Evaluation of the actwity of the cold expeller neem oil (Azadirachta indica A. Juss.) and the fractions derived through solvent partitioning, against Drechslera oryzae, Fusarium oxysporum and Alternaria tenuis showed that the active antifungal fraction is a mixture of tetranortriterpenoids. ...
Fitoterapia, 2001
... (Simaroubaceae), seeds and bark were collected in December 1998 from Kerala, India and the pl... more ... (Simaroubaceae), seeds and bark were collected in December 1998 from Kerala, India and the plant was identified by Dr RN Ravindran, Indian ... 4. Govindachari TR, Narasimhan NS, SureshG., Partho PD, Geetha Gopalakrishnan, Krishna Kumari GN J Chem ...
Proceedings / Indian Academy of Sciences
ABSTRACT
Proceedings: Animal Sciences
The herbal medicine industry is presently adopting modern scientific tools to substantiate the gu... more The herbal medicine industry is presently adopting modern scientific tools to substantiate the guarantee of efficacy that, in the past, rested only on anecdotal evidence derived from traditional knowledge systems. This is particularly true for the processes of identification of herbal raw materials adopting modern tools for phytochemical fingerprinting. The successful adaptation of available technologies and practices depends on an understanding of the phytochemical complexity and variability innate in biological material. It challenges the "mainstream medicinal mindset" that "tend(s) to reject …. therapies for which mechanisms of action do not fit within Newtonian, biochemical orientation" (Dumoff, 2003). The herbal medicinal industry is independently evolving its own rigid quality assurance and control systems using Good Manufacturing Practice (GMP) and Good Laboratory Practice (GLP) guidelines, but it faces unique difficulties. These include lack of Good Agricultural and Collection Practice (GACP), lack of transparency in the raw material supply chain so as to preclude the use of unsafe practices, problems in the authentication of herbal raw materials, and a general lack of understanding of the need to reduce phytochemical variability in these materials. This paper explores these difficulties and outlines strategies to overcome them, but these strategies will require coordinated international government regulations to be fully effective.
Pesticide Science
... Page 2. 364 Geetha Gopalakrishnan, G. Suresh, S. Anandhi 1 Diethyl sulfate I ... LRMS were re... more ... Page 2. 364 Geetha Gopalakrishnan, G. Suresh, S. Anandhi 1 Diethyl sulfate I ... LRMS were recorded using a Shimadzu GCMS (QP1000A) mass spectrometer. HRMS were recorded using a Finnigan MAT 8230 mass spectro-meter with perfluorokerosene as reference sample. ...
International Journal of Molecular Sciences
Identification of bioactive natural products from plants starts with the screening of extracts fo... more Identification of bioactive natural products from plants starts with the screening of extracts for a desired bioactivity such as antimicrobial, antifungal, anti-cancer, anti-inflammatory, or neuroprotective. When the bioactivity shows sufficient potency, the plant material is subjected to bio-activity-guided fractionation, which involves, e.g., sequential extraction followed by chromatographic separation, including HPLC. The bioactive compounds are then structurally identified by high-resolution mass spectrometry and nuclear magnetic resonance (NMR). One of the questions that come up during the purification process is how much of the bioactivity originally present in the crude extract is preserved during the purification process. If this is the case, it is interesting to investigate if the loss of total bioactivity is caused by the loss of material during purification or by the degradation or evaporation of potent compounds. A further possibility would be the loss of synergy between...
Journal of Agricultural and Food Chemistry, 2002
Fitoterapia, 2000
Natural tetranortriterpenoids such as cedrelone from Toona ciliata, azadiradione from Azadirachta... more Natural tetranortriterpenoids such as cedrelone from Toona ciliata, azadiradione from Azadirachta indica, limonin, limonol and nomilinic acid from Citrus medica, along with some cedrelone derivatives were tested for their antifungal activity against Puccinia arachidis, a groundnut rust pathogen. Results show that cedrelone was the most effective in reducing rust pustule emergence. Replacement of functional groups or modification of the A or the B ring in cedrelone reduced the effectiveness indicating the importance of specific structural features for activity.
BMC Genomics, 2013
Background Pattern-oriented chemical profiling is increasingly being used to characterize the phy... more Background Pattern-oriented chemical profiling is increasingly being used to characterize the phytochemical composition of herbal medicines for quality control purposes. Ideally, a fingerprint of the biological effects should complement the chemical fingerprint. For ethical and practical reasons it is not possible to test each herbal extract in laboratory animals or humans. What is needed is a test system consisting of an organism with relevant biology and complexity that can serve as a surrogate in vitro system. The purpose of this study was to test the hypothesis that the Saccharomyces cerevisiae transcriptome might be used as an indicator of phytochemical variation of closely-related yet distinctly different extracts prepared from a single species of a phytogeographically widely distributed medicinal plant. We combined phytochemical profiling using chromatographic methods (HPTLC, HPLC-PDA-MS/MS) and gene expression studies using Affymetrix Yeast 2.0 gene chip with principal compo...
Phytoparasitica, 1998
Evaluation of the actwity of the cold expeller neem oil (Azadirachta indica A. Juss.) and the fra... more Evaluation of the actwity of the cold expeller neem oil (Azadirachta indica A. Juss.) and the fractions derived through solvent partitioning, against Drechslera oryzae, Fusarium oxysporum and Alternaria tenuis showed that the active antifungal fraction is a mixture of tetranortriterpenoids. ...
Fitoterapia, 2001
... (Simaroubaceae), seeds and bark were collected in December 1998 from Kerala, India and the pl... more ... (Simaroubaceae), seeds and bark were collected in December 1998 from Kerala, India and the plant was identified by Dr RN Ravindran, Indian ... 4. Govindachari TR, Narasimhan NS, SureshG., Partho PD, Geetha Gopalakrishnan, Krishna Kumari GN J Chem ...
Proceedings / Indian Academy of Sciences
ABSTRACT
Proceedings: Animal Sciences
The herbal medicine industry is presently adopting modern scientific tools to substantiate the gu... more The herbal medicine industry is presently adopting modern scientific tools to substantiate the guarantee of efficacy that, in the past, rested only on anecdotal evidence derived from traditional knowledge systems. This is particularly true for the processes of identification of herbal raw materials adopting modern tools for phytochemical fingerprinting. The successful adaptation of available technologies and practices depends on an understanding of the phytochemical complexity and variability innate in biological material. It challenges the "mainstream medicinal mindset" that "tend(s) to reject …. therapies for which mechanisms of action do not fit within Newtonian, biochemical orientation" (Dumoff, 2003). The herbal medicinal industry is independently evolving its own rigid quality assurance and control systems using Good Manufacturing Practice (GMP) and Good Laboratory Practice (GLP) guidelines, but it faces unique difficulties. These include lack of Good Agricultural and Collection Practice (GACP), lack of transparency in the raw material supply chain so as to preclude the use of unsafe practices, problems in the authentication of herbal raw materials, and a general lack of understanding of the need to reduce phytochemical variability in these materials. This paper explores these difficulties and outlines strategies to overcome them, but these strategies will require coordinated international government regulations to be fully effective.
Pesticide Science
... Page 2. 364 Geetha Gopalakrishnan, G. Suresh, S. Anandhi 1 Diethyl sulfate I ... LRMS were re... more ... Page 2. 364 Geetha Gopalakrishnan, G. Suresh, S. Anandhi 1 Diethyl sulfate I ... LRMS were recorded using a Shimadzu GCMS (QP1000A) mass spectrometer. HRMS were recorded using a Finnigan MAT 8230 mass spectro-meter with perfluorokerosene as reference sample. ...