Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Suman Chandra is active.

Publication


Featured researches published by Suman Chandra.


Journal of Forensic Sciences | 2010

Potency Trends of Δ9‐THC and Other Cannabinoids in Confiscated Cannabis Preparations from 1993 to 2008*

Zlatko Mehmedic; Suman Chandra; Desmond Slade; Heather Denham; Susan Foster; Amit S. Patel; Samir A. Ross; Ikhlas A. Khan; Mahmoud A. ElSohly

Abstract:  The University of Mississippi has a contract with the National Institute on Drug Abuse (NIDA) to carry out a variety of research activities dealing with cannabis, including the Potency Monitoring (PM) program, which provides analytical potency data on cannabis preparations confiscated in the United States. This report provides data on 46,211 samples seized and analyzed by gas chromatography‐flame ionization detection (GC‐FID) during 1993–2008. The data showed an upward trend in the mean Δ9‐tetrahydrocannabinol (Δ9‐THC) content of all confiscated cannabis preparations, which increased from 3.4% in 1993 to 8.8% in 2008. Hashish potencies did not increase consistently during this period; however, the mean yearly potency varied from 2.5–9.2% (1993–2003) to 12.0–29.3% (2004–2008). Hash oil potencies also varied considerably during this period (16.8 ± 16.3%). The increase in cannabis preparation potency is mainly due to the increase in the potency of nondomestic versus domestic samples.


Biological Psychiatry | 2016

Changes in Cannabis Potency Over the Last 2 Decades (1995–2014): Analysis of Current Data in the United States

Mahmoud A. ElSohly; Zlatko Mehmedic; Susan Foster; Chandrani Gon; Suman Chandra; James C. Church

BACKGROUND Marijuana is the most widely used illicit drug in the United States and all over the world. Reports indicate that the potency of cannabis preparation has been increasing. This report examines the concentration of cannabinoids in illicit cannabis products seized by the U.S. Drug Enforcement Administration over the last 2 decades, with particular emphasis on Δ(9)-tetrahydrocannabinol and cannabidiol. METHODS Samples in this report were received over time from materials confiscated by the Drug Enforcement Administration and processed for analysis using a validated gas chromatography with flame ionization detector method. RESULTS Between January 1, 1995, and December 31, 2014, 38,681 samples of cannabis preparations were received and analyzed. The data showed that although the number of marijuana samples seized over the last 4 years has declined, the number of sinsemilla samples has increased. Overall, the potency of illicit cannabis plant material has consistently increased over time since 1995 from ~4% in 1995 to ~12% in 2014. The cannabidiol content has decreased on average from ~.28% in 2001 to <.15% in 2014, resulting in a change in the ratio of Δ(9)-tetrahydrocannabinol to cannabidiol from 14 times in 1995 to ~80 times in 2014. CONCLUSIONS There is a shift in the production of illicit cannabis plant material from regular marijuana to sinsemilla. This increase in potency poses higher risk of cannabis use, particularly among adolescents.


Physiology and Molecular Biology of Plants | 2009

Propagation through alginate encapsulation of axillary buds of Cannabis sativa L. — an important medicinal plant

Hemant Lata; Suman Chandra; Ikhlas A. Khan; Mahmoud A. ElSohly

Cannabis sativa L. (Cannabaceae) is an important medicinal plant well known for its pharmacologic and therapeutic potency. Because of allogamous nature of this species, it is difficult to maintain its potency and efficacy if grown from the seeds. Therefore, chemical profile-based screening, selection of high yielding elite clones and their propagation using biotechnological tools is the most suitable way to maintain their genetic lines. In this regard, we report a simple and efficient method for the in vitro propagation of a screened and selected high yielding drug type variety of Cannabis sativa, MX-1 using synthetic seed technology. Axillary buds of Cannabis sativa isolated from aseptic multiple shoot cultures were successfully encapsulated in calcium alginate beads. The best gel complexation was achieved using 5 % sodium alginate with 50 mM CaCl2.2H2O. Regrowth and conversion after encapsulation was evaluated both under in vitro and in vivo conditions on different planting substrates. The addition of antimicrobial substance — Plant Preservative Mixture (PPM) had a positive effect on overall plantlet development. Encapsulated explants exhibited the best regrowth and conversion frequency on Murashige and Skoog medium supplemented with thidiazuron (TDZ 0.5 μM) and PPM (0.075 %) under in vitro conditions. Under in vivo conditions, 100 % conversion of encapsulated explants was obtained on 1:1 potting mix- fertilome with coco natural growth medium, moistened with full strength MS medium without TDZ, supplemented with 3 % sucrose and 0.5 % PPM. Plantlets regenerated from the encapsulated explants were hardened off and successfully transferred to the soil. These plants are selected to be used in mass cultivation for the production of biomass as a starting material for the isolation of THC as a bulk active pharmaceutical.


Annals of Allergy Asthma & Immunology | 2013

Characterization of Cannabis sativa allergens

Ajay P. Nayak; Brett J. Green; Gordon L. Sussman; Noam Berlin; Hemant Lata; Suman Chandra; Mahmoud A. ElSohly; Justin M. Hettick; Donald H. Beezhold

BACKGROUND Allergic sensitization to Cannabis sativa is rarely reported, but the increasing consumption of marijuana has resulted in an increase in the number of individuals who become sensitized. To date, little is known about the causal allergens associated with C sativa. OBJECTIVE To characterize marijuana allergens in different components of the C sativa plant using serum IgE from marijuana sensitized patients. METHODS Serum samples from 23 patients with a positive skin prick test result to a crude C sativa extract were evaluated. IgE reactivity was variable between patients and C sativa extracts. IgE reactivity to C sativa proteins in Western blots was heterogeneous and ranged from 10 to 70 kDa. Putative allergens derived from 2-dimensional gels were identified. RESULTS Prominent IgE reactive bands included a 23-kDa oxygen-evolving enhancer protein 2 and a 50-kDa protein identified to be the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase. Additional proteins were identified in the proteomic analysis, including those from adenosine triphosphate synthase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, and luminal binding protein (heat shock protein 70), suggesting these proteins are potential allergens. Deglycosylation studies helped refine protein allergen identification and demonstrated significant IgE antibodies against plant oligosaccharides that could help explain cross-reactivity. CONCLUSION Identification and characterization of allergens from C sativa may be helpful in further understanding allergic sensitization to this plant species.


Journal of Biological Chemistry | 2013

Functional identification of valerena-1,10-diene synthase, a terpene synthase catalyzing a unique chemical cascade in the biosynthesis of biologically active sesquiterpenes in Valeriana officinalis

Yun Soo Yeo; S. Eric Nybo; Amar G. Chittiboyina; A Weerasooriya; Yh Wang; Elsa Góngora-Castillo; Brieanne Vaillancourt; C. Robin Buell; Dean DellaPenna; Mary Dawn Celiz; A. Daniel Jones; Eve Syrkin Wurtele; Nick Ransom; Natalia Dudareva; Khaled A. Shaaban; Nidhi Tibrewal; Suman Chandra; Tj Smillie; Ikhlas A. Khan; Robert M. Coates; David S. Watt; Joseph Chappell

Background: Therapeutic values of Valeriana officinalis have been associated with sesquiterpenes whose biosynthetic origins have remained enigmatic. Results: A cyclobutenyl intermediate in the catalytic cascade of valerena-1,10-diene synthase is reported. Conclusion: A new class of sesquiterpene synthases for the biosynthesis of sesquiterpenes harboring isobutenyl functional groups is proposed. Significance: Similar catalytic mechanisms from evolutionarily diverse organisms are proposed and portend sources for sesquiterpene diversity. Valerian is an herbal preparation from the roots of Valeriana officinalis used as an anxiolytic and sedative and in the treatment of insomnia. The biological activities of valerian are attributed to valerenic acid and its putative biosynthetic precursor valerenadiene, sesquiterpenes, found in V. officinalis roots. These sesquiterpenes retain an isobutenyl side chain whose origin has been long recognized as enigmatic because a chemical rationalization for their biosynthesis has not been obvious. Using recently developed metabolomic and transcriptomic resources, we identified seven V. officinalis terpene synthase genes (VoTPSs), two that were functionally characterized as monoterpene synthases and three that preferred farnesyl diphosphate, the substrate for sesquiterpene synthases. The reaction products for two of the sesquiterpene synthases exhibiting root-specific expression were characterized by a combination of GC-MS and NMR in comparison to the terpenes accumulating in planta. VoTPS7 encodes for a synthase that biosynthesizes predominately germacrene C, whereas VoTPS1 catalyzes the conversion of farnesyl diphosphate to valerena-1,10-diene. Using a yeast expression system, specific labeled [13C]acetate, and NMR, we investigated the catalytic mechanism for VoTPS1 and provide evidence for the involvement of a caryophyllenyl carbocation, a cyclobutyl intermediate, in the biosynthesis of valerena-1,10-diene. We suggest a similar mechanism for the biosynthesis of several other biologically related isobutenyl-containing sesquiterpenes.


Planta Medica | 2010

High frequency plant regeneration from leaf derived callus of high Δ9-tetrahydrocannabinol yielding Cannabis sativa L.

Hemant Lata; Suman Chandra; Ikhlas A. Khan; Mahmoud A. ElSohly

An efficient in vitro propagation protocol for rapidly producing Cannabis sativa plantlets from young leaf tissue was developed. Using gas chromatography-flame ionization detection (GC-FID), high THC yielding elite female clone of a drug-type CANNABIS variety (MX) was screened and its vegetatively propagated clones were used for micropropagation. Calli were induced from leaf explant on Murashige and Skoog medium supplemented with different concentrations (0.5, 1.0, 1.5, and 2.0 µM) of indole- 3-acetic acid (IAA), indole- 3- butyric acid (IBA), naphthalene acetic acid (NAA), and 2,4-dichlorophenoxy-acetic acid (2,4-D) in combination with 1.0 µM of thidiazuron (TDZ) for the production of callus. The optimum callus growth and maintenance was in 0.5 µM NAA plus 1.0 µM TDZ. The two-month-old calli were subcultured to MS media containing different concentrations of cytokinins (BAP, KN, TDZ). The rate of shoot induction and proliferation was highest in 0.5 µM TDZ. Of the various auxins (IAA, IBA, and NAA) tested, regenerated shoots rooted best on half strength MS medium (1/2 - MS) supplemented with 2.5 µM IBA. The rooted plantlets were successfully established in soil and grown to maturity with no gross variations in morphology and cannabinoids content at a survival rate of 95 % in the indoor growroom.


Planta Medica | 2010

Assessment of the genetic stability of micropropagated plants of Cannabis sativa by ISSR markers.

Hemant Lata; Suman Chandra; Natascha Techen; Ikhlas A. Khan; Mahmoud A. ElSohly

Inter-simple sequence repeat (ISSR) markers were used to evaluate the genetic stability of the micropropagated plants of Cannabis sativa over 30 passages in culture and hardening in soil for 8 months. A total of 15 ISSR primers resulted in 115 distinct and reproducible bands. All the ISSR profiles from micropropagated plants were monomorphic and comparable to mother plants, confirming the genetic stability among clones and mother plants. Chemical analysis of cannabinoids, using gas chromatography/flame ionization detection (GC/FID), was done to further confirm whether the qualitative and quantitative differences in the major secondary metabolites exist between the mother plant and micropropagated plants. Six major cannabinoids - Delta(9)-THC, THCV, CBD, CBC, CBG, and CBN - were identified and compared with the mother plant. Our results clearly showed a similar cannabinoid profile and insignificant differences in THC content between the two types of plants. These results suggest that the micropropagation protocol developed by us for rapid IN VITRO multiplication is appropriate and applicable for clonal mass propagation of C. SATIVA.


Planta Medica | 2010

Assessment of cannabinoids content in micropropagated plants of Cannabis sativa and their comparison with conventionally propagated plants and mother plant during developmental stages of growth.

Suman Chandra; Hemant Lata; Zlatko Mehmedic; Ikhlas A. Khan; Mahmoud A. ElSohly

Gas chromatography-flame ionization detection (GC-FID) was used to assess the chemical profile and quantification of cannabinoids to identify the differences, if existing, in the chemical constituents of in vitro propagated plants (IVP), conventionally grown plants (VP) and indoor grown mother plants (MP-Indoor) of a high THC yielding variety of Cannabis sativa L. during different developmental stages of growth. In general, THC content in all groups increased with plant age up to a highest level during the budding stage where the THC content reached a plateau before the onset of senescence. The pattern of changes observed in the concentration of other cannabinoids content with plants age has followed a similar trend in all groups of plants. Qualitatively, cannabinoids profiles obtained using GC-FID, in MP-indoor, VP and IVP plants were found to be similar to each other and to that of the field grown mother plant (MP field) of C. sativa. Minor differences observed in cannabinoids concentration within and among the groups were not found to be statistically significant. Our results confirm the clonal fidelity of IVP plants of C. sativa and suggest that the biochemical mechanism used in this study to produce the micropropagated plants does not affect the metabolic content and can be used for the mass propagation of true to type plants of this species for commercial pharmaceutical use.


Progress in the chemistry of organic natural products | 2017

Phytochemistry of Cannabis sativa L.

Mahmoud A. ElSohly; Mohamed M. Radwan; Waseem Gul; Suman Chandra; Ahmed Galal

Cannabis (Cannabis sativa, or hemp) and its constituents-in particular the cannabinoids-have been the focus of extensive chemical and biological research for almost half a century since the discovery of the chemical structure of its major active constituent, Δ9-tetrahydrocannabinol (Δ9-THC). The plants behavioral and psychotropic effects are attributed to its content of this class of compounds, the cannabinoids, primarily Δ9-THC, which is produced mainly in the leaves and flower buds of the plant. Besides Δ9-THC, there are also non-psychoactive cannabinoids with several medicinal functions, such as cannabidiol (CBD), cannabichromene (CBC), and cannabigerol (CBG), along with other non-cannabinoid constituents belonging to diverse classes of natural products. Today, more than 560 constituents have been identified in cannabis. The recent discoveries of the medicinal properties of cannabis and the cannabinoids in addition to their potential applications in the treatment of a number of serious illnesses, such as glaucoma, depression, neuralgia, multiple sclerosis, Alzheimers, and alleviation of symptoms of HIV/AIDS and cancer, have given momentum to the quest for further understanding the chemistry, biology, and medicinal properties of this plant.This contribution presents an overview of the botany, cultivation aspects, and the phytochemistry of cannabis and its chemical constituents. Particular emphasis is placed on the newly-identified/isolated compounds. In addition, techniques for isolation of cannabis constituents and analytical methods used for qualitative and quantitative analysis of cannabis and its products are also reviewed.


Analytical and Bioanalytical Chemistry | 2009

Genetic individualization of Cannabis sativa by a short tandem repeat multiplex system

Maria Mendoza; DeEtta Mills; Hemant Lata; Suman Chandra; Mahmoud A. ElSohly; José R. Almirall

Cannabis sativa is the most frequently used of all illicit drugs in the USA. Cannabis has been used throughout history for its stems in the production of hemp fiber, seed for oil and food, and buds and leaves as a psychoactive drug. Short tandem repeats (STRs) were chosen as molecular markers owing to their distinct advantages over other genetic methods. STRs are codominant, can be standardized such that reproducibility between laboratories can be easily achieved, have a high discrimination power, and can be multiplexed. In this study, six STR markers previously described for C. sativa were multiplexed into one reaction. The multiplex reaction was able to individualize 98 cannabis samples (14 hemp and 84 marijuana, authenticated as originating from 33 of the 50 states of the USA) and detect 29 alleles averaging 4.8 alleles per loci. The data did not relate the samples from the same state to each other. This is the first study to report a single-reaction sixplex and apply it to the analysis of almost 100 cannabis samples of known geographic origin.

Collaboration


Dive into the Suman Chandra's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar

Hemant Lata

University of Mississippi

View shared research outputs
Top Co-Authors

Avatar

Ikhlas A. Khan

University of Mississippi

View shared research outputs
Top Co-Authors

Avatar

Zlatko Mehmedic

University of Mississippi

View shared research outputs
Top Co-Authors

Avatar

Natascha Techen

University of Mississippi

View shared research outputs
Top Co-Authors

Avatar

Desmond Slade

University of Mississippi

View shared research outputs
Top Co-Authors

Avatar

Bharathi Avula

University of Mississippi

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Samir A. Ross

University of Mississippi

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge