Application of HR-MAS NMR spectroscopy for studying chemotype variations of Withania somnifera (L.) Dunal

Linking processes to community functions—insights into litter decomposition combining fungal metatranscriptomics and environmental NMR profiling

In forest ecosystems, decomposition is essential for carbon and nutrient cycling and therefore a key process for ecosystem functioning. During the decomposition process, litter chemistry, involved decomposer organisms, and enzymatic activity change interdependently. Chemical composition of the litter is the most complex and dynamic component in the decomposition process and therefore challenging to assess holistically. In this study, we aimed to characterize chemical shifts during decomposition and link them to changes in decomposer fungal activity. We characterized the chemical composition of freshly fallen autumn leaves of European beech (Fagus sylvatica) and the corresponding leaf litter after 1 year of decomposition by proton nuclear magnetic resonance spectroscopy. We further tested the applicability of spiking experiments for qualitative and quantitative characterization of leaves and litter chemistry. The composition and transcriptional activity of fungal communities was assessed by high-throughput Illumina sequencing in the same litter samples. We were able to distinguish freshly fallen leaves from 1-year-old litter based on their chemical composition. Chemical composition of leaves converged among regions with progressing decomposition. Fungal litter communities differed in composition among regions, but they were functionally redundant according to the expression of genes encoding litter degrading enzymes (CAZymes). Fungi of the saprotrophic genera Mycena and Chalara correlated with transcription of litter-degrading CAZymes in 1-year-old litter. Forestry measures influenced the diversity and transcription rate of the detected CAZymes transcripts in litter. Their expression was primarily predicted by composition of the soluble chemical fraction of the litter. Environmental NMR fingerprints thus proved valuable for inferring ecological contexts. We propose and discuss a holistic framework to link fungal activity, enzyme expression, and chemical composition.

NMR technique and methodology in botanical health product analysis and quality control

Botanicals have played an important role in maintaining human health and well-being throughout history. During the past few decades in particular, the use of botanical health products has gained more popularity. Whereas, quality, safety and efficacy concerns have continuously been critical issues due to the intrinsic chemical complexity of botanicals. Chemical analytical technologies play an imperative role in addressing these issues. Nuclear magnetic resonance (NMR) spectroscopy has proven to be a powerful and useful tool for the investigation of botanical health products. In this review, NMR techniques and methodologies that have been successfully applied to the research and development of botanical health products in all stages, from plants to products, are discussed and summarized. Furthermore, applications of NMR together with other analytical techniques in a variety of domains of botanical health products investigation, such as plant species differentiation, adulteration detection, and bio-activity evaluation, are discussed and illustrated with typical examples. This article provides an overview of the potential uses of NMR techniques and methodologies in an attempt to further promote their recognition and utilization in the field of botanical health products analysis and quality control.

The Botanical Safety Consortium: A public-private partnership to enhance the botanical safety toolkit

Botanical dietary supplement use is widespread and growing, therefore, ensuring the safety of botanical products is a public health priority. This commentary describes the mission and objectives of the Botanical Safety Consortium (BSC) - a public-private partnership aimed at enhancing the toolkit for conducting the safety evaluation of botanicals. This partnership is the result of a Memorandum of Understanding between the US FDA, the National Institute of Environmental Health Sciences, and the Health and Environmental Sciences Institute. The BSC serves as a global forum for scientists from government, academia, consumer health groups, industry, and non-profit organizations to work collaboratively on adapting and integrating new approach methodologies (NAMs) into routine botanical safety assessments. The objectives of the BSC are to: 1) engage with a group of global stakeholders to leverage scientific safety approaches; 2) establish appropriate levels of chemical characterization for botanicals as complex mixtures; 3) identify pragmatic, fit-for-purpose NAMs to evaluate botanical safety; 4) evaluate the application of these tools via comparison to the currently available safety information on selected botanicals; 5) and integrate these tools into a framework that can facilitate the evaluation of botanicals. Initially, the BSC is focused on oral exposure from dietary supplements, but this scope could be expanded in future phases of work. This commentary provides an overview of the structure, goals, and strategies of this initiative and insights regarding our first objectives, namely the selection and prioritization of botanicals based on putative toxicological properties.

Experimental evidence and mechanism of action of some popular neuro-nutraceutical herbs

Brain and neuronal circuits constitute the most complex organ networks in human body. They not only control and coordinate functions of all other organs, but also represent one of the most-affected systems with stress, lifestyle and age. With global increase in aging populations, these neuropathologies have emerged as major concern for maintaining quality of life. Recent era has witnessed a surge in nutritional remediation of brain dysfunctions primarily by "nutraceuticals" that refer to functional foods and supplements with pharmacological potential. Specific dietary patterns with a balanced intake of carbohydrates, fatty acids, vitamins and micronutrients have also been ascertained to promote brain health. Dietary herbs and their phytochemicals with wide range of biological and pharmacological activities and minimal adverse effects have gained remarkable attention as neuro-nutraceuticals. Neuro-nutraceutical potentials of herbs are often expressed as effects on cognitive response, circadian rhythm, neuromodulatory, antioxidant and anti-inflammatory activities that are mediated by effects on gene expression, epigenetics, protein synthesis along with their turnover and metabolic pathways. Epidemiological and experimental evidence have implicated enormous applications of herbal supplementation in neurodegenerative and psychiatric disorders. The present review highlights the identification, experimental evidence and applications of some herbs including Bacopa monniera, Withania somnifera, Curcuma longa, Helicteres angustifolia, Undaria pinnatifida, Haematococcus pluvialis, and Vitis vinifera, as neuro-nutraceuticals.

Ashwagandha: Advances in plant biotechnological approaches for propagation and production of bioactive compounds

ETHNOPHARMACOLOGICAL RELEVANCE

Withania somnifera is one of the most extensively delved Ayurvedic medicine. Apart from rejuvenation and increasing longevity, it has several other properties such as immunomodulation, anti-cancer, anti-stress and neuroprotection. Because of its prevailing use and increasing demand, it becomes prudent to scientifically evaluate and document both its propagation and production of desired phytoconstituents.

AIM OF THE STUDY

This review aims to highlight the research progress achieved on various biotechnological and tissue culture aspects of Withania somnifera and to cover up-to-date information regarding in-vitro propagation and production of withanolides.

MATERIALS AND METHODS

Significant published studies were identified for the years 2000-2018 using Elsevier-Science Direct, Pubmed and Google scholar and several research studies in our laboratory. Following keywords such as "plant extracts", "in vitro cultures", "callus and suspension culture", "micropropagation", "hairy root cultures" were used. Further, "Withania somnifera", "secondary metabolites specially withanolides", "molecular techniques" and "in vitro conservation" were used to cross-reference the keywords.

RESULTS

Ashwagandha comprises a broad spectrum of phytochemicals with a wide range of pharmacological properties. W. somnifera seeds have reduced viability and germination rates; thus, its regular cultivation method fails to achieve commercial demands mainly for the production of desired phytoconstituents. Cultivation of plant cells/tissues under in vitro conditions and development of various biotechnological strategies will help to build an attractive alternative to provide adequate quality and quantity raw materials. Recently, a large number of in vitro protocols has developed for W. somnifera not only for its propagation but for the production of secondary metabolites as well. Present work highlights a variety of biotechnological strategies both for prompt propagation and production of different bioactive secondary metabolites.

CONCLUSION

The present review focuses on the development and opportunities in various biotechnological approaches to accomplish the global demand of W. somnifera and its secondary metabolites. This review underlines the advances in plant biotechnological approaches for the propagation of W. somnifera and production of its bioactive compounds.

Metabolomics of Withania somnifera (L.) Dunal: Advances and applications

ETHNOPHARMACOLOGICAL RELEVANCE

Withania somnifera L. (Solanaceae), commonly known as Ashwagandha or Indian ginseng, is used in Ayurveda (Indian system of traditional medicine) for vitality, cardio-protection and treating other ailments, such as neurological disorders, gout, and skin diseases.

AIM OF THE REVIEW

We present a critical overview of the information on the metabolomics of W. somnifera and highlight the significance of the technique for use in quality control of medicinal products. We have also pointed out the use of metabolomics to distinguish varieties and to identify best methods of cultivation, collection, as well as extraction.

MATERIAL AND METHODS

The relevant information on medicinal value, phytochemical studies, metabolomics of W. somnifera, and their applications were collected from a rigorous electronic search through scientific databases, including Scopus, PubMed, Web of Science and Google Scholar. Structures of selected metabolites were from the PubChem.

RESULTS

The pharmacological activities of W. somnifera were well documented. Roots are the most important parts of the plant used in Ayurvedic preparations. Stem and leaves also have a rich content of bioactive phytochemicals like steroidal lactones, alkaloids, and phenolic acids. Metabolomic studies revealed that metabolite profiles of W. somnifera depended on plant parts collected and the developmental stage of the plant, besides the season of sample collection and geographical location. The levels of withanolides were variable, depending on the morpho/chemotypes within the species of W. somnifera. Although studies on W. somnifera were initiated several years ago, the complexity of secondary metabolites was not realized due to the lack of adequate and fool-proof technology for phytochemical fingerprinting. Sophistications in chromatography coupled to mass spectrometry facilitated the discovery of several new metabolites. Mutually complementary techniques like LC-MS, GC-MS, HPTLC, and NMR were employed to obtain a comprehensive metabolomic profile. Subsequent data analyses and searches against spectral databases enabled the annotation of signals and dereplication of metabolites in several numbers without isolating them individually.

CONCLUSIONS

The present review provides a critical update of metabolomic data and the diverse application of the technique. The identification of parameters for standardization and quality control of herbal products is essential to facilitate mandatory checks for the purity of formulation. Such studies would enable us to identify the best geographical location of plants and the time of collection. We recommend the use of metabolomic analysis of herbal products based on W. somnifera for quality control as well as the discovery of novel bioactive compounds.

HR-MAS NMR Applications in Plant Metabolomics

Metabolomics is used to reduce the complexity of plants and to understand the underlying pathways of the plant phenotype. The metabolic profile of plants can be obtained by mass spectrometry or liquid-state NMR. The extraction of metabolites from the sample is necessary for both techniques to obtain the metabolic profile. This extraction step can be eliminated by making use of high-resolution magic angle spinning (HR-MAS) NMR. In this review, an HR-MAS NMR-based workflow is described in more detail, including used pulse sequences in metabolomics. The pre-processing steps of one-dimensional HR-MAS NMR spectra are presented, including spectral alignment, baseline correction, bucketing, normalisation and scaling procedures. We also highlight some of the models which can be used to perform multivariate analysis on the HR-MAS NMR spectra. Finally, applications of HR-MAS NMR in plant metabolomics are described and show that HR-MAS NMR is a powerful tool for plant metabolomics studies.

Metabolic response of soybean plants to Sclerotinia sclerotiorum infection

White mold is a disease caused by the fungus Sclerotinia sclerotiorum, a highly destructive necrotrophic pathogen that infects soybean crops, among others. Usually, the infection triggers the plant defense system to minimize the damages. However, the effects of the infection on soybean plant metabolism are still unclear. In this work, the metabolic profiles of soybean stems and leaves were accessed using 1H HR-MAS NMR spectroscopy to identify metabolic changes as a response to S. sclerotiorum infection. This fungus widely affects the central metabolism of soybean plants, and most of the altered metabolites are involved in carbon metabolism, as suggested by the results. Furthermore, the metabolites of central metabolism can be associated with the production of several polyphenolic metabolites. Changes in metabolic profile of leaves indicate systemic effects.

Important issues in plant tissues analyses by HR-MAS NMR

INTRODUCTION

High-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy enables the analysis of the metabolic profile of plant and animal tissues under close to natural conditions, as well as of other heterogeneous natural or synthetic materials. Neither sample pretreatment is required after fragmentation nor powdering of the sample before insertion into the rotor. However, the efficiency of the method depends strongly on the sample preparation, rotor insertion procedure, and analysis conditions.

OBJECTIVE

To identify some of the variables that affect the spectral data and to propose solutions that minimise their impact on the quality of the analyses and results.

METHODS

Dried plant tissues were powdered, weighed, and homogenised in a 50 μL rotor with an optimised volume of deuterated solvent and sample in order to prevent material from escaping during spacer insertion, avoiding variations in magnetic susceptibility. Factors affecting the quality of HR-MAS NMR analysis such as particle size, sample and solvent amounts, solvent polarity, swelling time, rotor manipulation and pulse sequence setting were evaluated.

RESULTS

A strong correlation was observed between the signal area and the particle size of the powdered sample. The spectral profile varied depending on the deuterated solvent used. An incubation period was necessary to achieve adequate swelling of the sample and to ensure good data reproducibility. Proper sealing of the rotor, number of cycles and τ time on cpmgpr1d pulse sequence were found to affect the signal areas.

CONCLUSION

The study highlights the need for standardised sample preparation and instrumental setup protocols in order to achieve high reproducibility and obtain reliable data from HR-MAS NMR analyses.

Metabolomic and biotechnological approaches to determine therapeutic potential of Withania somnifera (L.) Dunal: A review

BACKGROUND

Withania somnifera, a high value medicinal plant is a major source of pharmaceutically important active compounds withanolides. Withania somnifera has been used in ayurveda as health restorative and anabolic agent besides having anti-arthritic, antidepressant, anti-microbial, anti-inflammatory, anti-diabetic, anti-stress, neuroprotective and cardio-protective activities.

HYPOTHESIS/PURPOSE

The mining of the compound(s) of interest offers opportunity to identify desired attributes in the therapeutic area of interest. Metabolomic has become an important tool in the field of pharmacological and functional genomics of medicinal plants. The analysis supports the information regarding differential outline of the gene expression for increasing important withanolides viz. withanolide A and withaferin A in W. somnifera.

STUDY DESIGN

The bioinformatics and biotechnological approaches viz. tissue culture, genetic transformation, genomic, transcriptomic, proteomic, gene mining and metabolomic studies have opened new windows about engineering of withanolide production.

METHODS

Target and network analysis for maximum therapeutic potential of Withania somnifera have been determined by employing Genemania software for finding interactions among various human genes that are being affected by active constituents.

RESULTS

Some of the major bioactive compounds of Withania somnifera have been discussed on protein-protein, protein-DNA and genetic interactions with respect to gene and protein expression data, protein domains, metabolic profiling, root organ culture, genetic transformation and phenotypic screening profiles CONCLUSION: The implementation of latest bioinformatic tools in combination with biotechnological techniques for breeding platforms are important in conservation of medicinal plant species in danger. The current review is based on molecular and in vitro methodologies employed in W. somnifera for accepting their importance in the improvement of this valuable medicinal species.

Metabolic Study of Dioecy in Mauritia flexuosa: NMR-based and Chemometric Approaches

INTRODUCTION

Mauritia flexuosa is a dioecious species native to the Amazon, and the gender identification can currently be determined through the differentiation between female and male flowers in the first flowering.

OBJECTIVES

To identify variations in the metabolome profiles of pooled and individual samples of leaves from female and male plants of M. flexuosa in reproductive phase, and the plant in its vegetative phase, using two extraction systems.

MATERIAL AND METHODS

Extractions of leaves were separately conducted using deuterated water and methanol. The extracts were evaluated by NMR spectroscopy and chemometric methods.

RESULTS

Different NMR spectroscopic profiles were observed for females, males, and plants in the vegetative phase. Significant variations were found in the carbohydrate and fatty acid contents for the aqueous and methanolic extracts, respectively. Although principal component analysis (PCA) has not been efficient to distinguish the genders, orthogonal signal correction/partial least squares-discriminant analysis (OPLS-DA) was able to successfully differentiate male and female plants in the reproductive phase, independently on the sampling approach. For plants in the vegetative phase, OPLS-DA method from aqueous extracts of M. flexuosa leaves also distinguished female samples from the others and showed a small overlap between male and young plants, while the classification model was not able to be used for prediction.

CONCLUSIONS

NMR spectroscopy and chemometric-based approach was demonstrated to be useful in the metabolic study of dioecy in M. flexuosa. The extracts of the leaves allowed for differentiation between male and female plants; however, for plants in the vegetative phase, the identification of the gender was not effective. Copyright © 2018 John Wiley & Sons, Ltd.

Endophytes of Withania somnifera modulate in planta content and the site of withanolide biosynthesis

Tissue specific biosynthesis of secondary metabolites is a distinguished feature of medicinal plants. Withania somnifera, source of pharmaceutically important withanolides biosynthesizes withaferin-A in leaves and withanolide-A in roots. To increase the in planta withanolides production, a sustainable approach needs to be explored. Here, we isolated endophytes from different parts of W. somnifera plants and their promising role in in planta withanolide biosynthesis was established in both in-vivo grown as well in in-vitro raised composite W. somnifera plants. Overall, the fungal endophytes improved photosynthesis, plant growth and biomass, and the root-associated bacterial endophytes enhanced the withanolide content in both in-vivo and in-vitro grown plants by modulating the expression of withanolide biosynthesis genes in leaves and roots. Surprisingly, a few indole-3-acetic acid (IAA)-producing and nitrogen-fixing root-associated endophytes could induce the biosynthesis of withaferin-A in roots by inducing in planta IAA-production and upregulating the expression of withanolide biosynthesis genes especially MEP-pathway genes (DXS and DXR) in roots as well. Results indicate the role of endophytes in modulating the synthesis and site of withanolides production and the selected endophytes can be used for enhancing the in planta withanolide production and enriching roots with pharmaceutically important withaferin-A which is generally absent in roots.

Triethylene glycol-like effects of Ashwagandha (Withania somnifera (L.) Dunal) root extract devoid of withanolides in stressed mice

Background

The objective of the study is to compare stress resistance-promoting effect of triethylene glycol (TEG) and root extract of Ashwagandha (Withania somnifera) i.e. withanolide-free root extract of Withania somnifera (WFWS).

Materials and Methods

Mice groups treated orally with 10 mg/kg TEG or WFWS (3.3, 10, 33.3, or 100 mg/kg) for 12 consecutive days were subjected to foot shock stress-triggered hyperthermia test on the 1^st, 5^th, 7^th and 10^th day and to marble-burying test on the following 2 days. Effects of treatment on stress-triggered alteration in body weight, core temperature, blood glucose, insulin and cortisol level were quantified and statistically analyzed.

Results

WFWS doses up to 10 mg/kg/day were as effective as TEG in affording protection against stress-triggered alteration in body weight, core temperature and marble-burying behavior. Protection against stress-triggered alteration in blood glucose and insulin level, as well as antidepressants or anxiolytic-like activities in the behavioral test, were observed in the higher two WFWS doses (33.3 and 100 mg/kg) treated groups only.

Conclusion

Ashwagandha metabolites other than withanolides contribute to its stress resistance increasing effects. The observations suggest that modulation of physiological functions of gut microbiota may be involved in the mode of action of Withania somnifera root extracts.

Metabolic Fingerprinting of Dormant and Active Flower Primordia of Ribes nigrum Using High-Resolution Magic Angle Spinning NMR

Global warming may modify the timing of dormancy release and spring growth of buds of temperate fruit crops. Environmental regulation of the activity-dormancy cycle in perennial plants remains poorly understood at the metabolic level. Especially, the fine-scale metabolic dynamics in the meristematic zone within buds has received little attention. In this work we performed metabolic profiling of intact floral primordia of Ribes nigrum isolated from buds differing in dormancy status using high-resolution magic angle spinning (HR-MAS) NMR. The technique proved useful in monitoring different groups of metabolites, e.g., carbohydrates and amino acids, in floral primordia and allowed metabolic separation of primordia from endo- and ecodormant buds. In addition, due to its nondestructive character, HR-MAS NMR may provide novel insights into cellular compartmentation of individual biomolecules that cannot be obtained using liquid-state NMR. Out results show that HR-MAS NMR may be an important method for metabolomics of intact plant structures.

Withania somnifera: Advances and Implementation of Molecular and Tissue Culture Techniques to Enhance Its Application

Withania somnifera, commonly known as Ashwagandha an important medicinal plant largely used in Ayurvedic and indigenous medicine for over 3,000 years. Being a medicinal plant, dried powder, crude extract as well as purified metabolies of the plant has shown promising therapeutic properties. Withanolides are the principal metabolites, responsible for the medicinal properties of the plant. Availability and amount of particular withanolides differ with tissue type and chemotype and its importance leads to identification characterization of several genes/ enzymes related to withanolide biosynthetic pathway. The modulation in withanolides can be achieved by controlling the environmental conditions like, different tissue culture techniques, altered media compositions, use of elicitors, etc. Among all the in vitro techniques, hairy root culture proved its importance at industrial scale, which also gets benefits due to more accumulation (amount and number) of withanolides in roots tissues of W. somnifera. Use of media compostion and elicitors further enhances the amount of withanolides in hairy roots. Another important modern day technique used for accumulation of desired secondary metabolites is modulating the gene expression by altering environmental conditions (use of different media composition, elicitors, etc.) or through genetic enginnering. Knowing the significance of the gene and the key enzymatic step of the pathway, modulation in withanolide contents can be achieved upto required amount in therapeutic industry. To accomplish maximum productivity through genetic enginnering different means of Withania transformation methods have been developed to obtain maximum transformation efficiency. These standardized transformation procedues have been used to overexpress/silence desired gene in W. somnifera to understand the outcome and succeed with enhanced metabolic production for the ultimate benefit of human race.

Novel Methods to Generate Active Ingredients-Enriched Ashwagandha Leaves and Extracts

Ashwagandha (Withania somnifera) is an Ayurvedic herb commonly used in world-renowned traditional Indian home medicine system. Roots of Ashwagandha have been traditionally known to possess a variety of therapeutic and health promoting potentials that have not been sufficiently supported by laboratory studies. Nevertheless, most, if not all, of the preventive and therapeutic potentials have been assigned to its bioactive components, steroidal alkaloids and lactones. In contrast to the traditional use of roots, we have been exploring bioactivities in leaves of Ashwagandha. Here, we report that the leaves possess higher content of active Withanolides, Withaferin-A (Wi-A) and Withanone (Wi-N), as compared to the roots. We also established, for the first time, hydroponic cultivation of Ashwagandha and investigated the effect of various cultivation conditions on the content of Wi-A and Wi-N by chemical analysis and bioassays. We report that the Withanone/Withaferin A-rich leaves could be obtained by manipulating light condition during hydroponic cultivation. Furthermore, we recruited cyclodextrins to prepare extracts with desired ratio of Wi-N and Wi-A. Hydroponically grown Ashwagandha and its extracts with high ratio of withanolides are valuable for cancer treatment.

Metabolic Profiling of Intact Arabidopsis thaliana Leaves during Circadian Cycle Using 1H High Resolution Magic Angle Spinning NMR

Arabidopsis thaliana is the most widely used model organism for research in plant biology. While significant advances in understanding plant growth and development have been made by focusing on the molecular genetics of Arabidopsis, extracting and understanding the functional framework of metabolism is challenging, both from a technical perspective due to losses and modification during extraction of metabolites from the leaves, and from the biological perspective, due to random variation obscuring how well the function is performed. The purpose of this work is to establish the in vivo metabolic profile directly from the Arabidopsis thaliana leaves without metabolite extraction, to reduce the complexity of the results by multivariate analysis, and to unravel the mitigation of cellular complexity by predominant functional periodicity. To achieve this, we use the circadian cycle that strongly influences metabolic and physiological processes and exerts control over the photosynthetic machinery. High resolution-magic angle spinning nuclear magnetic resonance (HR-MAS NMR) was applied to obtain the metabolic profile directly from intact Arabidopsis leaves. Combining one- and two-dimensional 1H HR-MAS NMR allowed the identification of several metabolites including sugars and amino acids in intact leaves. Multivariate analysis on HR-MAS NMR spectra of leaves throughout the circadian cycle revealed modules of primary metabolites with significant and consistent variations of their molecular components at different time points of the circadian cycle. Since robust photosynthetic performance in plants relies on the functional periodicity of the circadian rhythm, our results show that HR-MAS NMR promises to be an important non-invasive method that can be used for metabolomics of the Arabidopsis thaliana mutants with altered physiology and photosynthetic efficiency.

Nootropic potential of Ashwagandha leaves: Beyond traditional root extracts

Rapidly increasing aging population and environmental stressors are the two main global concerns of the modern society. These have brought in light rapidly increasing incidence of a variety of pathological conditions including brain tumors, neurodegenerative & neuropsychiatric disorders, and new challenges for their treatment. The overlapping symptoms, complex etiology and lack of full understanding of the brain structure and function to-date further complicate these tasks. On the other hand, several herbal reagents with a long history of their use have been asserted to possess neurodifferentiation, neuroregenerative and neuroprotective potentials, and hence been recommended as supplement to enhance and maintain brain health and function. Although they have been claimed to function by holistic approach resulting in maintaining body homeostasis and brain health, there are not enough laboratory studies in support to these and mechanism(s) of such beneficial activities remain largely undefined. One such herb is Ashwagandha, also called "Queen of Ayurveda" for its popular use in Indian traditional home medicine because of its extensive benefits including anticancer, anti-stress and remedial potential for aging and neurodegenerative pathologies. However, active principles and underlying mechanism(s) of action remain largely unknown. Here we provide a review on the effects of Ashwagandha extracts and active principles, and underlying molecular mechanism(s) for brain pathologies. We highlight our findings on the nootropic potential of Ashwagandha leaves. The effects of Ashwagandha leaf extracts are multidimensional ranging from differentiation of neuroblastoma and glioma cells, reversal of Alzheimer and Parkinson's pathologies, protection against environmental neurotoxins and enhancement of memory.

NMR-Based Metabolomic Analysis of Huanglongbing-Asymptomatic and -Symptomatic Citrus Trees

Huanglongbing (HLB) is one of the most severe diseases that affects citrus trees worldwide and is associated with the yet uncultured bacteria Candidatus Liberibacter spp. To assess the metabolomic differences between HLB-asymptomatic and -symptomatic tissues, extracts from leaf and root samples taken from a uniform 6-year-old commercial orchard of Valencia trees were subjected to nuclear magnetic resonance (NMR) and chemometrics. The results show that the symptomatic trees had higher sucrose content in their leaves and no variation in their roots. In addition, proline betaine and malate were detected in smaller amounts in the HLB-affected symptomatic leaves. The changes in metabolic processes of the plant in response to HLB are corroborated by the relationship between the bacterial levels and the metabolic profiles.

Comprehensive multiphase NMR: a promising technology to study plants in their native state

Nuclear magnetic resonance (NMR) spectroscopy is arguably one the most powerful tools to study the interactions and molecular structure within plants. Traditionally, however, NMR has developed as two separate fields, one dealing with liquids and the other dealing with solids. Plants in their native state contain components that are soluble, swollen, and true solids. Here, a new form of NMR spectroscopy, developed in 2012, termed comprehensive multiphase (CMP)-NMR is applied for plant analysis. The technology composes all aspects of solution, gel, and solid-state NMR into a single NMR probe such that all components in all phases in native unaltered samples can be studied and differentiated in situ. The technology is evaluated using wild-type Arabidopsis thaliana and the cellulose-deficient mutant ectopic lignification1 (eli1) as examples. Using CMP-NMR to study intact samples eliminated the bias introduced by extraction methods and enabled the acquisition of a more complete structural and metabolic profile; thus, CMP-NMR revealed molecular differences between wild type (WT) and eli1 that could be overlooked by conventional methods. Methanol, fatty acids and/or lipids, glutamine, phenylalanine, starch, and nucleic acids were more abundant in eli1 than in WT. Pentaglycine was present in A. thaliana seedlings and more abundant in eli1 than in WT.

Approaches in fostering quality parameters for medicinal botanicals in the Indian context

India is among the important megabiodiversity centers of the world with nearly 45,000 known plant species. This diversity coupled with a rich heritage of traditional knowledge has made India a home to several important time-honored systems of health care such as Ayurveda, Siddha and Unani. Herbal medicines, however, are associated with a number of shortcomings including uniform efficacy and lack of appropriate quality control measures at various stages of product development. The review intends to outline the importance of fostering quality parameters towards standardization and manufacturing of botanicals for India to emerge as a leader in global market of herbal products. Literature survey was carried out on important parameters for processing and manufacturing of botanicals. The review highlights that there have been constant efforts for developing state of the art technologies in the field of herbal research. It also reflects that Government authorities have also taken a number of initiatives to formulate appropriate guidelines from standardization of raw materials to obtaining botanical products. However, in the Indian context, there exist certain lacunae in the current regulatory mechanisms which need to be strengthened and stringently implemented to ensure safety, purity and efficacy of herbal medicines. Towards this the approaches being developed globally can be adopted. Based on the literature reviewed, in our opinion, four areas viz., benefit sharing, investment by industry, standardization and national/international networking structure need immediate attention for strengthening Traditional Systems of Medicine in India.

HR-MAS NMR metabolomics of 'Swingle' citrumelo rootstock genetically modified to overproduce proline

The accumulation of proline is a typical physiological response to abiotic stresses in higher plants. 'Swingle' citrumelo, an important rootstock for citrus production, has been modified with a mutated Δ(1)-pyrroline-5-carboxylate synthetase gene (VaP5CSF129A) linked to the cauliflower mosaic virus 35S promoter to induce the overproduction of free proline. This paper presents a comparative metabolomic study of nontransgenic versus transgenic 'Swingle' citrumelo plants with high endogenous proline. (1)H high-resolution magic angle spinning nuclear magnetic resonance spectroscopy and multivariate analysis showed significant differences in some metabolites between the nontransgenic and transgenic leaves and roots. The overproduction of proline has reduced the sucrose content in transgenic leaves, revealing a metabolic cost for these plants. In roots, the high level of free proline acts for the adjustment of cation-anion balance, causing the reduction of acetic acid content. The same sucrose level in roots indicates that they can be considered as sucrose sink. Similar behavior may be waited for fruits produced on transgenic rootstock.

Characterization of Withania somnifera leaf transcriptome and expression analysis of pathogenesis-related genes during salicylic acid signaling

Withania somnifera (L.) Dunal is a valued medicinal plant with pharmaceutical applications. The present study was undertaken to analyze the salicylic acid induced leaf transcriptome of W. somnifera. A total of 45.6 million reads were generated and the de novo assembly yielded 73,523 transcript contig with average transcript contig length of 1620 bp. A total of 71,062 transcripts were annotated and 53,424 of them were assigned GO terms. Mapping of transcript contigs to biological pathways revealed presence of 182 pathways. Seventeen genes representing 12 pathogenesis-related (PR) families were mined from the transcriptome data and their pattern of expression post 17 and 36 hours of salicylic acid treatment was documented. The analysis revealed significant up-regulation of all families of PR genes by 36 hours post treatment except WsPR10. The relative fold expression of transcripts ranged from 1 fold to 6,532 fold. The two families of peroxidases including the lignin-forming anionic peroxidase (WsL-PRX) and suberization-associated anionic peroxidase (WsS-PRX) recorded maximum expression of 377 fold and 6532 fold respectively, while the expression of WsPR10 was down-regulated by 14 fold. Additionally, the most stable reference gene for normalization of qRT-PCR data was also identified. The effect of SA on the accumulation of major secondary metabolites of W. somnifera including withanoside V, withaferin A and withanolide A was also analyzed and an increase in content of all the three metabolites were detected. This is the first report on expression patterns of PR genes during salicylic acid signaling in W. somnifera.

Enhanced methanol production in plants provides broad spectrum insect resistance

Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR) and spectra showed up to 16 fold higher methanol as compared to control wild type (WT) plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid) and Bemisia tabaci (whitefly), respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants.

Pectin methylesterase of Datura species, purification, and characterization from Datura stramonium and its application

Pectin methylesterases (PME; EC 3.1.1.11) involved in de-esterification of pectin and have applicability in food, textiles, wines, pulp, and paper industries. In the present study, we compared PME activity of different parts of 3 Datura species and found that fruit coat showed maximum PME activity followed by leaf and seed. PME from leaves of D. stramonium (DsPME) was purified and characterized. DsPME showed optimum activity at 60 °C and pH 9 in the presence of 0.3 M NaCl. DsPME was stable at 70 °C and retained more than 40% activity after 60 min of incubation. However, enzyme activity completely abolished at 80 after 5 min of incubation. It follows Michaelis-Menten enzyme kinetics. Km and Vmax with citrus pectin were 0.008 mg/ml and 16.96 µmol/min, respectively. DsPME in combination with polygalactourenase (PGA) increased the clarity of orange, apple, pomegranate and pineapple juices by 2.9, 2.6, 2.3, and 3.6 fold, respectively in comparison to PGA alone. Due to very high de-esterification activity, easy denaturation and significant efficacy in incrementing clarification of fruit juice makes DsPME useful for industrial application.

Metabolic profiling for studying chemotype variations in Withania somnifera (L.) Dunal fruits using GC-MS and NMR spectroscopy

Withania somnifera (L.) Dunal (Solanaceae), commonly known as Ashwagandha, is one of the most valued Indian medicinal plant with several pharmaceutical and nutraceutical applications. Metabolic profiling was performed by GC-MS and NMR spectroscopy on the fruits obtained from four chemotypes of W. somnifera. A combination of (1)H NMR spectroscopy and GC-MS identified 82 chemically diverse metabolites consisting of organic acids, fatty acids, aliphatic and aromatic amino acids, polyols, sugars, sterols, tocopherols, phenolic acids and withanamides in the fruits of W. somnifera. The range of metabolites identified by GC-MS and NMR of W. somnifera fruits showed various known and unknown metabolites. The primary and secondary metabolites observed in this study represent MVA, DOXP, shikimic acid and phenylpropanoid biosynthetic metabolic pathways. Squalene and tocopherol have been rated as the most potent naturally occurring compounds with antioxidant properties. These compounds have been identified by us for the first time in the fruits of W. somnifera. Multivariate principal component analysis (PCA) on GC-MS and NMR data revealed clear distinctions in the primary and secondary metabolites among the chemotypes. The variation in the metabolite concentration among different chemotypes of the fruits of W. somnifera suggest that specific chemovars can be used to obtain substantial amounts of bioactive ingredients for use as potential pharmacological and nutraceuticals agents.

De novo assembly, functional annotation and comparative analysis of Withania somnifera leaf and root transcriptomes to identify putative genes involved in the withanolides biosynthesis

Withania somnifera is one of the most valuable medicinal plants used in Ayurvedic and other indigenous medicine systems due to bioactive molecules known as withanolides. As genomic information regarding this plant is very limited, little information is available about biosynthesis of withanolides. To facilitate the basic understanding about the withanolide biosynthesis pathways, we performed transcriptome sequencing for Withania leaf (101L) and root (101R) which specifically synthesize withaferin A and withanolide A, respectively. Pyrosequencing yielded 8,34,068 and 7,21,755 reads which got assembled into 89,548 and 1,14,814 unique sequences from 101L and 101R, respectively. A total of 47,885 (101L) and 54,123 (101R) could be annotated using TAIR10, NR, tomato and potato databases. Gene Ontology and KEGG analyses provided a detailed view of all the enzymes involved in withanolide backbone synthesis. Our analysis identified members of cytochrome P450, glycosyltransferase and methyltransferase gene families with unique presence or differential expression in leaf and root and might be involved in synthesis of tissue-specific withanolides. We also detected simple sequence repeats (SSRs) in transcriptome data for use in future genetic studies. Comprehensive sequence resource developed for Withania, in this study, will help to elucidate biosynthetic pathway for tissue-specific synthesis of secondary plant products in non-model plant organisms as well as will be helpful in developing strategies for enhanced biosynthesis of withanolides through biotechnological approaches.