Plant Metabolites Drive Different Responses in Caterpillars of Two Closely Related Helicoverpa Species

The host acceptances of insects can be determined largely by detecting plant metabolites using insect taste. In the present study, we investigated the gustatory sensitivity and feeding behaviors of two closely related caterpillars, the generalist Helicoverpa armigera (Hübner) and the specialist H. assulta (Guenée), to different plant metabolites by using the single sensillum recording technique and the dual-choice assay, aiming to explore the contribution of plant metabolites to the difference of diet breadth between the two species. The results depicted that the feeding patterns of caterpillars for both plant primary and secondary metabolites were significantly different between the two Helicoverpa species. Fructose, glucose, and proline stimulated feedings of the specialist H. assulta, while glucose and proline had no significant effect on the generalist H. armigera. Gossypol and tomatine, the secondary metabolites of host plants of the generalist H. armigera, elicited appetitive feedings of this insect species but drove aversive feedings of H. assulta. Nicotine and capsaicin elicited appetitive feedings of H. assulta, but drove aversive feedings of H. armigera. For the response of gustatory receptor neurons (GRNs) in the maxillary styloconic sensilla of caterpillars, each of the investigated primary metabolites induced similar responding patterns between the two Helicoverpa species. However, four secondary metabolites elicited different responding patterns of GRNs in the two species, which is consistent with the difference of feeding preferences to these compounds. In summary, our results of caterpillars’ performance to the plant metabolites could reflect the difference of diet breadth between the two Helicoverpa species. To our knowledge, this is the first report showing that plant secondary metabolites could drive appetitive feedings in a generalist insect species, which gives new insights of underscoring the adaptation mechanism of herbivores to host plants.

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Bioactive Secondary Metabolites from Endophytic Fungi

Current Medicinal Chemistry ◽

10.2174/0929867326666190916144709 ◽

2020 ◽

Vol 27 (11) ◽

pp. 1836-1854 ◽

Cited By ~ 5

Author(s):

Elena Ancheeva ◽

Georgios Daletos ◽

Peter Proksch

Keyword(s):

Secondary Metabolites ◽

Endophytic Fungi ◽

Host Plants ◽

Biological Activities ◽

Cytotoxic Agents ◽

Special Focus ◽

Plant Metabolites ◽

Direct Production ◽

Bioactive Secondary Metabolites ◽

Fungal Genes

Background: Endophytes represent a complex community of microorganisms colonizing asymptomatically internal tissues of higher plants. Several reports have shown that endophytes enhance the fitness of their host plants by direct production of bioactive secondary metabolites, which are involved in protecting the host against herbivores and pathogenic microbes. In addition, it is increasingly apparent that endophytes are able to biosynthesize medicinally important “phytochemicals”, originally believed to be produced only by their host plants. Objective: The present review provides an overview of secondary metabolites from endophytic fungi with pronounced biological activities covering the literature between 2010 and 2017. Special focus is given on studies aiming at exploration of the mode of action of these metabolites towards the discovery of leads from endophytic fungi. Moreover, this review critically evaluates the potential of endophytic fungi as alternative sources of bioactive “plant metabolites”. Results: Over the past few years, several promising lead structures from endophytic fungi have been described in the literature. In this review, 65 metabolites are outlined with pronounced biological activities, primarily as antimicrobial and cytotoxic agents. Some of these metabolites have shown to be highly selective or to possess novel mechanisms of action, which hold great promises as potential drug candidates. Conclusion: Endophytes represent an inexhaustible reservoir of pharmacologically important compounds. Moreover, endophytic fungi could be exploited for the sustainable production of bioactive “plant metabolites” in the future. Towards this aim, further insights into the dynamic endophyte - host plant interactions and origin of endophytic fungal genes would be of utmost importance.

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Target screening of plant secondary metabolites in river waters by liquid chromatography coupled to high-resolution mass spectrometry (LC–HRMS)

Environmental Sciences Europe ◽

10.1186/s12302-020-00399-2 ◽

2020 ◽

Vol 32 (1) ◽

Author(s):

Mulatu Yohannes Nanusha ◽

Martin Krauss ◽

Carina D. Schönsee ◽

Barbara F. Günthardt ◽

Thomas D. Bucheli ◽

...

Keyword(s):

Secondary Metabolites ◽

Surface Waters ◽

High Resolution Mass Spectrometry ◽

Water Cycle ◽

Endocrine Disrupting Chemicals ◽

Plant Secondary Metabolites ◽

Biologically Active ◽

Plant Metabolites ◽

River Waters ◽

Target Screening

Abstract Background Substantial efforts have been made to monitor potentially hazardous anthropogenic contaminants in surface waters while for plant secondary metabolites (PSMs) almost no data on occurrence in the water cycle are available. These metabolites enter river waters through various pathways such as leaching, surface run-off and rain sewers or input of litter from vegetation and might add to the biological activity of the chemical mixture. To reduce this data gap, we conducted a LC–HRMS target screening in river waters from two different catchments for 150 plant metabolites which were selected from a larger database considering their expected abundance in the vegetation, their potential mobility, persistence and toxicity in the water cycle and commercial availability of standards. Results The screening revealed the presence of 12 out of 150 possibly toxic PSMs including coumarins (bergapten, scopoletin, fraxidin, esculetin and psoralen), a flavonoid (formononetin) and alkaloids (lycorine and narciclasine). The compounds narciclasine and lycorine were detected at concentrations up to 3 µg/L while esculetin and fraxidin occurred at concentrations above 1 µg/L. Nine compounds occurred at concentrations above 0.1 µg/L, the Threshold for Toxicological Concern (TTC) for non-genotoxic and non-endocrine disrupting chemicals in drinking water. Conclusions Our study provides an overview of potentially biologically active PSMs in surface waters and recommends their consideration in monitoring and risk assessment of water resources. This is currently hampered by a lack of effect data including toxicity to aquatic organisms, endocrine disruption and genotoxicity and demands for involvement of these compounds in biotesting.

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The Health Promoting Bioactivities of Lactuca sativa can be Enhanced by Genetic Modulation of Plant Secondary Metabolites

Metabolites ◽

10.3390/metabo9050097 ◽

2019 ◽

Vol 9 (5) ◽

pp. 97 ◽

Cited By ~ 4

Author(s):

Hammad Ismail ◽

Anna L. Gillespie ◽

Danielle Calderwood ◽

Haroon Iqbal ◽

Colene Gallagher ◽

...

Keyword(s):

Secondary Metabolites ◽

Lactuca Sativa ◽

Genetic Manipulation ◽

Sesquiterpene Lactones ◽

Plant Secondary Metabolites ◽

Rol Genes ◽

In Vitro Bioactivity ◽

New Paradigm ◽

Plant Metabolites

Plant secondary metabolites are protective dietary constituents and rol genes evidently increase the synthesis of these versatile phytochemicals. This study subjected a globally important vegetable, lettuce (Lactuca sativa) to a combination of untargeted metabolomics (LC-QTof-MS) and in vitro bioactivity assays. Specifically, we examined the differences between untransformed cultured lettuce (UnT), lettuce transformed with either rolABC (RA) or rolC (RC) and commercially grown (COM) lettuce. Of the 5333 metabolite features aligned, deconvoluted and quantified 3637, 1792 and 3737 significantly differed in RA, RC and COM, respectively, compared with UnT. In all cases the number of downregulated metabolites exceeded the number increased. In vitro bioactivity assays showed that RA and RC (but not COM) significantly improved the ability of L. sativa to inhibit α-glucosidase, inhibit dipeptidyl peptidase-4 (DPP-4) and stimulate GLP-1 secretion. We putatively identified 76 lettuce metabolites (sesquiterpene lactones, non-phenolic and phenolic compounds) some of which were altered by several thousand percent in RA and RC. Ferulic acid levels increased 3033–9777%, aminooxononanoic acid increased 1141–1803% and 2,3,5,4′tetrahydroxystilbene-2-O-β-d-glucoside increased 40,272–48,008%. Compound activities were confirmed using commercially obtained standards. In conclusion, rol gene transformation significantly alters the metabolome of L.sativa and enhances its antidiabetic properties. There is considerable potential to exploit rol genes to modulate secondary metabolite production for the development of novel functional foods. This investigation serves as a new paradigm whereby genetic manipulation, metabolomic analysis and bioactivity techniques can be combined to enable the discovery of novel natural bioactives and determine the functional significance of plant metabolites.

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The diversification of downy mildew species was not driven by the loss of mycorrhizal associations or the evolution of C4 photosynthesis

PhytoFrontiers™ ◽

10.1094/phytofr-04-21-0027-r ◽

2021 ◽

Author(s):

William J Davis ◽

Jo Anne Crouch

Keyword(s):

Secondary Metabolites ◽

Host Plant ◽

Downy Mildew ◽

Host Plants ◽

C4 Photosynthesis ◽

Plant Secondary Metabolites ◽

Free Carbon ◽

Photosynthetic Pathway ◽

Mycorrhizal Associations ◽

C3 Photosynthesis

There are approximately 700 obligate biotrophic species grouped into 20 genera (Oomycota, Peronosporaceae) that cause downy mildew diseases. Dick hypothesized in 2001 that diversification of downy mildew species was driven, in part, by host plant secondary metabolites. Dick further speculated that this was driven by the transition of host plants away from mycorrhizal associations or the evolution of C4 photosynthesis. Specifically, loss of mycorrhizal associations or the use of C4 photosynthesis would result in more free carbon that the plants could then use to produce more secondary metabolites. If true, then there should be more downy mildew species that infect hosts from plant lineages that lack mycorrhizal associations or use C4 photosynthesis. However, analysis of 677 downy mildew species for host plant mycorrhizal associations and host plant photosynthetic pathway type show that this is not what occurred. Seventy percent of downy mildew species parasitize hosts that form mycorrhizal associations and 94% of downy mildew species parasitize hosts that use C3 photosynthesis. From this, it is concluded that the diversification of downy mildew species was not driven by the loss of mycorrhizal associations or the evolution of C4 photosynthesis. However, 85% of downy mildew species that parasitize Poaceae (grasses) parasitize C4 hosts. Thus, it is possible that C4 photosynthesis plays a role in the diversification of these genera.

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Plant secondary metabolites as defenses, regulators and primary metabolites- The blurred functional trichotomy

10.31219/osf.io/6ba7r ◽

2020 ◽

Author(s):

Matthias Erb ◽

Daniel J. Kliebenstein

Keyword(s):

Secondary Metabolites ◽

Plant Growth ◽

Plant Secondary Metabolites ◽

Trophic Levels ◽

Primary Metabolism ◽

Plant Metabolites ◽

Small Molecular Weight ◽

Primary Metabolites ◽

Environmental Selection ◽

Plant Environment

The plant kingdom produces hundreds of thousands of small molecular weight organic compounds. Based on their assumed functions, the research community has classified them into three overarching groups: primary metabolites which are directly required for plant growth, secondary (or specialized) metabolites which mediate plant-environment interactions and hormones which regulate organismal processes, including metabolism. For decades, this functional trichotomy has shaped theory and experimentation in plant biology. However, evidence is accumulating that the boundaries between the different types of metabolites are blurred. An increasing number of mechanistic studies demonstrate that secondary metabolites are multifunctional and can act as potent regulators of plant growth and defense. Secondary metabolites are also re-integrated into primary metabolism, thus behaving like primary metabolites sensu lato. Several adaptive scenarios may have favored this functional diversity for secondary metabolites, including signaling robustness and cost-effective storage and recycling. Secondary metabolite multi-functionality can provide new explanations for ontogenetic patterns of defense production and can refine our understanding of plant-herbivore interactions, in particular by accounting for the discovery that adapted herbivores misuse plant secondary metabolites for multiple purposes, some of which mirror their functions in plants. In conclusion, recent work unveils the limits of our current classification system for plant metabolites and suggests that viewing them as integrated components of metabolic networks that are dynamically shaped by environmental selection pressures and transcend multiple trophic levels can improve our understanding of plant metabolism and plant-environment interactions.

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Target screening of plant secondary metabolites in river waters by liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS)

10.21203/rs.3.rs-36114/v2 ◽

2020 ◽

Author(s):

Mulatu Yohannes Nanusha ◽

Martin Krauss ◽

Carina D. Schönsee ◽

Barbara F. Günthardt ◽

Thomas D. Bucheli ◽

...

Keyword(s):

Secondary Metabolites ◽

Surface Waters ◽

High Resolution Mass Spectrometry ◽

Water Cycle ◽

Endocrine Disrupting Chemicals ◽

Plant Secondary Metabolites ◽

Biologically Active ◽

Plant Metabolites ◽

River Waters ◽

Target Screening

Abstract Background: Substantial efforts have been made to monitor potentially hazardous anthropogenic contaminants in surface waters while for plant secondary metabolites (PSMs) almost no data on occurrence in the water cycle are available. These metabolites enter river waters through various pathways such as leaching, surface run-off and rain sewers or input of litter from vegetation and might add to the biological activity of the chemical mixture. To reduce this data gap we conducted a LC-HRMS target screening in river waters from two different catchments for 150 plant metabolites which were selected from a larger database considering their expected abundance in the vegetation, their potential mobility, persistence and toxicity in the water cycle and commercial availability of standards. Results: The screening revealed the presence of 12 out of 150 possibly toxic PSMs including coumarins (bergapten, scopoletin, fraxidin, esculetin and psoralen), a flavonoid (formononetin) and alkaloids (lycorine and narciclasine). The compounds narciclasine and lycorine were detected at concentrations up to 3 µg/L while esculetin and fraxidin occurred at concentrations above 1 µg/L. Nine compounds occurred at concentrations above 0.1 µg/L, the Threshold for Toxicological Concern (TTC) for non-genotoxic and non-endocrine disrupting chemicals in drinking water. Conclusions: Our study provides an overview of potentially biologically active PSMs in surface waters and recommends their consideration in monitoring and risk assessment of water resources. This is currently hampered by a lack of effect data including toxicity to aquatic organisms, endocrine disruption and genotoxicity and demands for involvement of these compounds in biotesting.

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Potential Anti-Mycobacterium tuberculosis Activity of Plant Secondary Metabolites: Insight with Molecular Docking Interactions

Antioxidants ◽

10.3390/antiox10121990 ◽

2021 ◽

Vol 10 (12) ◽

pp. 1990

Author(s):

Manu Kumar ◽

Sandeep Kumar Singh ◽

Prem Pratap Singh ◽

Vipin Kumar Singh ◽

Avinash Chandra Rai ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Secondary Metabolites ◽

Antimicrobial Agents ◽

Early Stage ◽

Plant Secondary Metabolites ◽

Adverse Side Effect ◽

Plant Metabolites ◽

In Silico Studies ◽

Wide Range ◽

Health Complications

Tuberculosis (TB) is a recurrent and progressive disease, with high mortality rates worldwide. The drug-resistance phenomenon of Mycobacterium tuberculosis is a major obstruction of allelopathy treatment. An adverse side effect of allelopathic treatment is that it causes serious health complications. The search for suitable alternatives of conventional regimens is needed, i.e., by considering medicinal plant secondary metabolites to explore anti-TB drugs, targeting the action site of M. tuberculosis. Nowadays, plant-derived secondary metabolites are widely known for their beneficial uses, i.e., as antioxidants, antimicrobial agents, and in the treatment of a wide range of chronic human diseases (e.g., tuberculosis), and are known to “thwart” disease virulence. In this regard, in silico studies can reveal the inhibitory potential of plant-derived secondary metabolites against Mycobacterium at the very early stage of infection. Computational approaches based on different algorithms could play a significant role in screening plant metabolites against disease virulence of tuberculosis for drug designing.

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An Overview of COVID-19 and the Potential Plant Harboured Secondary Metabolites against SARS-CoV-2: A Review

Journal of Pure and Applied Microbiology ◽

10.22207/jpam.15.3.52 ◽

2021 ◽

Vol 15 (3) ◽

pp. 1059-1071

Author(s):

C.T. Swamy

Keyword(s):

Secondary Metabolites ◽

Pulmonary Veins ◽

Experimental Studies ◽

Plant Metabolites ◽

Primary And Secondary Metabolites ◽

Quinoline Alkaloids ◽

Main Protease ◽

Current Scenario ◽

Novel Coronavirus

The SARS-CoV-2 virus causes COVID-19, a pandemic disease, and it is called the novel coronavirus. It belongs to the Coronaviridae family and has been plagued the world since the end of 2019. Viral infection to the lungs causes fluid filling and breathing difficulties, which leads to pneumonia. Pneumonia progresses to ARDS (Acute Respiratory Distress Syndrome), in which fluid fills the air sac and seeps from the pulmonary veins. In the current scenario, several vaccines have been used to control the pandemic worldwide. Even though vaccines are available and their effectiveness is short, it may be helpful to curb the pandemic, but long-term protection is inevitable when we look for other options. Plants have diversified components such as primary and secondary metabolites. These molecules show several activities such as anti-microbial, anti-cancer, anti-helminthic. In addition, these molecules have good binding ability to the SARS-CoV-2 virus proteins such as RdRp (RNA-dependent RNA polymerase), Mpro (Main Protease), etc. Therefore, these herbal molecules could probably be used to control the COVID-19. However, pre-requisite tests, such as cytotoxicity, in vivo, and human experimental studies, are required before plant molecules can be used as potent drugs. Plant metabolites such as alkaloids, isoquinoline ß-carboline, and quinoline alkaloids such as skimmianine, quinine, cinchonine, and dictamine are present in plants and used in a traditional medicinal system.

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Pinpointing secondary metabolites that shape the composition and function of the plant microbiome

Journal of Experimental Botany ◽

10.1093/jxb/eraa424 ◽

2020 ◽

Author(s):

Richard P Jacoby ◽

Anna Koprivova ◽

Stanislav Kopriva

Keyword(s):

Secondary Metabolites ◽

Plant Secondary Metabolites ◽

Plant Metabolites ◽

Microbiome Composition ◽

Body Of Knowledge ◽

Microbial Responses ◽

Root Chemistry ◽

And Function ◽

Functional Mechanisms ◽

Plant Microbiome

Abstract One of the major questions in contemporary plant science involves determining the functional mechanisms that plants use to shape their microbiome. Plants produce a plethora of chemically diverse secondary metabolites, many of which exert bioactive effects on microorganisms. Several recent publications have unequivocally shown that plant secondary metabolites affect microbiome composition and function. These studies have pinpointed that the microbiome can be influenced by a diverse set of molecules, including: coumarins, glucosinolates, benzoxazinoids, camalexin, and triterpenes. In this review, we summarize the role of secondary metabolites in shaping the plant microbiome, highlighting recent literature. A body of knowledge is now emerging that links specific plant metabolites with distinct microbial responses, mediated via defined biochemical mechanisms. There is significant potential to boost agricultural sustainability via the targeted enhancement of beneficial microbial traits, and here we argue that the newly discovered links between root chemistry and microbiome composition could provide a new set of tools for rationally manipulating the plant microbiome.

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ROLE OF PLANT SECONDARY METABOLITES IN COMBATING PEST INDUCED STRESS IN BRINJAL (SOLANUM MELONGENA L.)

Journal of Environmental Engineering and Landscape Management ◽

10.3846/jeelm.2021.14432 ◽

2021 ◽

Vol 29 (4) ◽

pp. 449-453

Author(s):

Pratik Talukder ◽

Debankita Dutta ◽

Elija Ghosh ◽

Indrani Bose ◽

Sourish Bhattacharjee

Keyword(s):

Secondary Metabolites ◽

Developmental Stages ◽

Plant Secondary Metabolites ◽

Solanum Melongena ◽

Calorific Value ◽

Plant Metabolites ◽

Complex Interactions ◽

Fruit Borer ◽

Solanaceae Family

Brinjal or eggplant (Solanum melongena L.) is known as a vegetable of diet because it contains high moisture and low calorific value. It is also a good source of antioxidants and phytonutrients. Brinjal is widely grown in the South and South-East Asian countries and is the second most important vegetable in India. It belongs to the Solanaceae family. Shoot and fruit borer (Leucinodes orbonalis) pest of brinjal is the most widespread one and it has the ability to affect any of the developmental stages of brinjal. Plants and their insect herbivores have had a long and intimate evolutionary association that has resulted in many complex interactions mediated by specialized plant metabolites like phenolics, alkaloids, terpenoids, cyanogenic glycosides etc. Frequent and excessive use of insecticides has become a common practice now which only increases the probability of resistance development and resurgence of pest. Hence to develop an effective approach to combat this pest understanding of its feeding mechanism and chemistry of its interaction with the fruit is necessary. The importance of the secondary metabolites in the field of chemical biology and in pest management is discussed in this study.

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