Pollen extracts and constituent sugars increase growth of a trypanosomatid parasite of bumble bees

Pollen extracts increase growth of a trypanosome parasite of bumble bees

10.7287/peerj.preprints.2730v1 ◽

2017 ◽

Author(s):

Evan C Palmer-Young

Keyword(s):

Inhibitory Activity ◽

Intestinal Parasites ◽

Plant Diseases ◽

Food Sources ◽

Growth Media ◽

Trypanosome Infection ◽

Floral Nectar ◽

Crithidia Bombi ◽

History Of ◽

History Of Use

Phytochemicals produced by plants, including at flowers, function in protection against plant diseases, and have a long history of use against trypanosome infection. Floral nectar and pollen, the sole food sources for many species of insect pollinators, contain phytochemicals that have been shown to reduce trypanosome infection in bumble and honey bees when fed as isolated compounds. Nectar and pollen, however, consist of phytochemical mixtures, which can have greater antimicrobial activity than do single compounds. This study tested the hypothesis that pollen extracts would inhibit parasite growth.Extracts of six different pollens were tested for direct inhibitory activity against cell cultures of the bumble bee trypanosome gut parasite Crithidia bombi. Surprisingly, pollen extracts increased parasite growth rather than inhibiting it. Experimental manipulations of growth media showed that supplemental monosaccharides (glucose and fructose) were sufficient to promote growth, while a common floral phytochemical (caffeic acid) with inhibitory activity against other trypanosomes had only weak inhibitory effects on Crithidia bombi. These results indicate that, although pollen is essential for bees and other pollinators, pollen may promote growth of intestinal parasites that are uninhibited by pollen phytochemicals and, as a result, can benefit from the nutrients that pollen provides.

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Pollen extracts increase growth of a trypanosome parasite of bumble bees

10.7287/peerj.preprints.2730 ◽

2017 ◽

Cited By ~ 1

Author(s):

Evan C Palmer-Young

Keyword(s):

Inhibitory Activity ◽

Intestinal Parasites ◽

Plant Diseases ◽

Food Sources ◽

Growth Media ◽

Trypanosome Infection ◽

Floral Nectar ◽

Crithidia Bombi ◽

History Of ◽

History Of Use

Phytochemicals produced by plants, including at flowers, function in protection against plant diseases, and have a long history of use against trypanosome infection. Floral nectar and pollen, the sole food sources for many species of insect pollinators, contain phytochemicals that have been shown to reduce trypanosome infection in bumble and honey bees when fed as isolated compounds. Nectar and pollen, however, consist of phytochemical mixtures, which can have greater antimicrobial activity than do single compounds. This study tested the hypothesis that pollen extracts would inhibit parasite growth.Extracts of six different pollens were tested for direct inhibitory activity against cell cultures of the bumble bee trypanosome gut parasite Crithidia bombi. Surprisingly, pollen extracts increased parasite growth rather than inhibiting it. Experimental manipulations of growth media showed that supplemental monosaccharides (glucose and fructose) were sufficient to promote growth, while a common floral phytochemical (caffeic acid) with inhibitory activity against other trypanosomes had only weak inhibitory effects on Crithidia bombi. These results indicate that, although pollen is essential for bees and other pollinators, pollen may promote growth of intestinal parasites that are uninhibited by pollen phytochemicals and, as a result, can benefit from the nutrients that pollen provides.

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The Role of Aromatase Enzyme in Hormone Related Diseases and Plant-Based Aromatase Inhibitors as Therapeutic Regimens

Current Topics in Medicinal Chemistry ◽

10.2174/1568026621666211129141631 ◽

2021 ◽

Vol 21 ◽

Author(s):

Kevser Taban Akça ◽

Murside Ayşe Demirel ◽

Ipek Süntar

Keyword(s):

Natural Products ◽

Aromatase Inhibitors ◽

Inhibitory Activity ◽

Chemical Compounds ◽

Synthesis Methods ◽

Herbal Drugs ◽

Drug Discovery And Development ◽

History Of ◽

History Of Use

: Medicinal plants have a long history of use as food and remedy in traditional and modern societies, as well as have been used as herbal drugs and sources of novel bioactive compounds. They provide a wide array of chemical compounds, many of which can not be synthesized via current synthesis methods. Natural products may provide aromatase inhibitory activity through various pathways and may act clinically effective for treating pathologies associated with excessive aromatase secretion including breast, ovarian and endometrial cancers, endometriosis, uterine fibroid, benign prostatic hyperplasia (BPH), prostate cancer, infertility, and gynecomastia. Recent studies have shown that natural products with aromatase inhibitory activity, could also be good options against secondary recurrence of breast cancer by exhibiting chemopreventive effects. Therefore, screening for new plant-based aromatase inhibitors may provide novel leads for drug discovery and development, particularly with increased clinical efficacy and decreased side effects.

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Serologic Markers of Previous Malaria Exposure and Functional Antibodies Inhibiting Parasite Growth Are Associated With Parasite Kinetics Following a Plasmodium falciparum Controlled Human Infection

Clinical Infectious Diseases ◽

10.1093/cid/ciz740 ◽

2019 ◽

Vol 70 (12) ◽

pp. 2544-2552 ◽

Cited By ~ 6

Author(s):

Jane Achan ◽

Isaie J Reuling ◽

Xi Zen Yap ◽

Edgard Dabira ◽

Abdullahi Ahmad ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Inhibitory Activity ◽

Quantitative Polymerase Chain Reaction ◽

Parasite Growth ◽

High Group ◽

Growth Inhibitory ◽

Growth Inhibitory Activity ◽

Malaria Exposure ◽

The Impact ◽

High Median

Abstract Background We assessed the impact of exposure to Plasmodium falciparum on parasite kinetics, clinical symptoms, and functional immunity after controlled human malaria infection (CHMI) in 2 cohorts with different levels of previous malarial exposure. Methods Nine adult males with high (sero-high) and 10 with low (sero-low) previous exposure received 3200 P. falciparum sporozoites (PfSPZ) of PfSPZ Challenge by direct venous inoculation and were followed for 35 days for parasitemia by thick blood smear (TBS) and quantitative polymerase chain reaction. Endpoints were time to parasitemia, adverse events, and immune responses. Results Ten of 10 (100%) volunteers in the sero-low and 7 of 9 (77.8%) in the sero-high group developed parasitemia detected by TBS in the first 28 days (P = .125). The median time to parasitemia was significantly shorter in the sero-low group than the sero-high group (9 days [interquartile range {IQR} 7.5–11.0] vs 11.0 days [IQR 7.5–18.0], respectively; log-rank test, P = .005). Antibody recognition of sporozoites was significantly higher in the sero-high (median, 17.93 [IQR 12.95–24] arbitrary units [AU]) than the sero-low volunteers (median, 10.54 [IQR, 8.36–12.12] AU) (P = .006). Growth inhibitory activity was significantly higher in the sero-high (median, 21.8% [IQR, 8.15%–29.65%]) than in the sero-low group (median, 8.3% [IQR, 5.6%–10.23%]) (P = .025). Conclusions CHMI was safe and well tolerated in this population. Individuals with serological evidence of higher malaria exposure were able to better control infection and had higher parasite growth inhibitory activity. Clinical Trials Registration NCT03496454.

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Wars between microbes on roots and fruits

F1000Research ◽

10.12688/f1000research.10696.1 ◽

2017 ◽

Vol 6 ◽

pp. 343 ◽

Cited By ~ 23

Author(s):

Ben Lugtenberg ◽

Daniel E. Rozen ◽

Faina Kamilova

Keyword(s):

Biological Control ◽

Volatile Organic Compounds ◽

Organic Compounds ◽

Defense Mechanisms ◽

Fruits And Vegetables ◽

Plant Diseases ◽

Food Sources ◽

Low Concentrations ◽

Volatile Organic ◽

Attack And Defense

Microbes in nature often live in unfavorable conditions. To survive, they have to occupy niches close to food sources and efficiently utilize nutrients that are often present in very low concentrations. Moreover, they have to possess an arsenal of attack and defense mechanisms against competing bacteria. In this review, we will discuss strategies used by microbes to compete with each other in the rhizosphere and on fruits, with a focus on mechanisms of inter- and intra-species antagonism. Special attention will be paid to the recently discovered roles of volatile organic compounds. Several microbes with proven capabilities in the art of warfare are being applied in products used for the biological control of plant diseases, including post-harvest control of fruits and vegetables.

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The Potential for Lunar and Martian Regolith Simulants to Sustain Plant Growth: A Multidisciplinary Overview

Frontiers in Astronomy and Space Sciences ◽

10.3389/fspas.2021.747821 ◽

2022 ◽

Vol 8 ◽

Author(s):

Luigi Giuseppe Duri ◽

Antonio Giandonato Caporale ◽

Youssef Rouphael ◽

Simona Vingiani ◽

Mario Palladino ◽

...

Keyword(s):

Plant Growth ◽

Physicochemical Properties ◽

Life Support ◽

Dynamic Environment ◽

Chemical Properties ◽

Mineralogical Composition ◽

Food Sources ◽

Growth Media ◽

Martian Regolith

Bioregenerative life support systems (BLSS) are conceived of and developed so as to provide food sources for crewed missions to the Moon or Mars. The in situ resource utilization (ISRU) approach aims to reduce terrestrial input into a BLSS by using native regoliths and recycled organic waste as primary resources. The combination of BLSS and ISRU may allow sustainable food production on Moon and Mars. This task poses several challenges, including the effects of partial gravity, the limited availability of oxygen and water, and the self-sustaining management of resources. Lunar and Martian regoliths are not available on Earth; therefore, space research studies are conducted on regolith simulants that replicate the physicochemical properties of extra-terrestrial regoliths (as assessed in situ by previous missions). This review provides an overview of the physicochemical properties and mineralogical composition of commercially available Lunar and Martian regolith simulants. Subsequently, it describes potential strategies and sustainable practices for creating regolith simulants akin to terrestrial soil, which is a highly dynamic environment where microbiota and humified organic matter interact with the mineral moiety. These strategies include the amendment of simulants with composted organic wastes, which can turn nutrient-poor and alkaline crushed rocks into efficient life-sustaining substrates equipped with enhanced physical, hydraulic, and chemical properties. In this regard, we provide a comprehensive analysis of recent scientific works focusing on the exploitation of regolith simulant-based substrates as plant growth media. The literature discussion helps identify the main critical aspects and future challenges related to sustainable space farming by the in situ use and enhancement of Lunar and Martian resources.

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Growth-Inhibitory Antibodies Are Not Necessary for Protective Immunity to Malaria Infection

Infection and Immunity ◽

10.1128/iai.00939-09 ◽

2009 ◽

Vol 78 (2) ◽

pp. 680-687 ◽

Cited By ~ 11

Author(s):

E. Elsa Herdiana Murhandarwati ◽

Lina Wang ◽

Harini D. de Silva ◽

Charles Ma ◽

Magdalena Plebanski ◽

...

Keyword(s):

Inhibitory Activity ◽

Transgenic Line ◽

Plasmodium Yoelii ◽

Parasite Growth ◽

Blood Stage ◽

Immune State ◽

Growth Inhibitory ◽

Growth Inhibitory Activity ◽

Inhibitory Antibodies

ABSTRACT The absence of a validated surrogate marker for the immune state has complicated the design of a subunit vaccine against asexual stages of Plasmodium falciparum. In particular, it is not known whether the capacity to induce antibodies that inhibit parasite growth in vitro is an important criterion for selection of P. falciparum proteins to be assessed in human vaccine trials. We examined this issue in the Plasmodium yoelii rodent malaria model using the 19-kDa C-terminal fragment of merozoite surface protein 1 (MSP119). To examine the relationship between inhibitory antibodies in immunized mice and the immune state, as indicated by resistance to a blood-stage challenge, we used an allelic replacement strategy to generate a transgenic P. falciparum line that expresses MSP119 from P. yoelii. We show that MSP119 is functionally conserved across these two divergent Plasmodium species, and replacing PfMSP119 with PyMSP119 has no detectable effect on parasite growth in vitro. By comparing growth rates of this transgenic line with a matched transgenic line that expresses the endogenous PfMSP119, we developed an assay to measure the specific growth-inhibitory activity directed exclusively to the PyMSP119 protein in the sera from vaccinated animals. To validate this assay, sera from rabbits immunized with recombinant PyMSP119 were tested and showed specific inhibitory activity in a concentration-dependent manner. In mice that were immunized with recombinant PyMSP119, the levels of PyMSP119-specific inhibitory activity did not correlate with the total antibody levels measured by enzyme-linked immunosorbent assay. Furthermore, they did not correlate with resistance to subsequent blood-stage infection, and some mice with complete protection showed no detectable inhibitory activity in their prechallenge sera. These data indicated that growth-inhibitory activity measured in vitro was not a reliable predictor of immune status in vivo, and the reliance on this criterion to select vaccine candidates for human clinical trials may be misplaced. The transgenic lines further offer useful tools for comparing the efficacy of MSP119-based vaccines that utilize different immunization regimens and antigen formulations.

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Bioactive Secondary Metabolites from Trichoderma spp. against Phytopathogenic Bacteria and Root-Knot Nematode

Microorganisms ◽

10.3390/microorganisms8030401 ◽

2020 ◽

Vol 8 (3) ◽

pp. 401 ◽

Cited By ~ 2

Author(s):

Raja Asad Ali Khan ◽

Saba Najeeb ◽

Zhenchuan Mao ◽

Jian Ling ◽

Yuhong Yang ◽

...

Keyword(s):

Secondary Metabolites ◽

Bacterial Cell ◽

Pathogenic Bacteria ◽

Parasitic Nematode ◽

Control Plant ◽

Plant Diseases ◽

Growth Media ◽

Trichoderma Spp ◽

Phytopathogenic Bacteria ◽

Bioactive Secondary Metabolites

Losses in crops caused by plant pathogenic bacteria and parasitic nematode are increasing because of a decrease in efficacy of traditional management measures. There is an urgent need to develop nonchemical and ecofriendly based management to control plant diseases. A potential approach of controlling plant disease in the crops is the use of biocontrol agents and their secondary metabolites (SMs). Luckily fungi and especially the genus Trichoderma comprise a great number of fungal strains that are the potential producer of bioactive secondary metabolites. In this study secondary metabolites from ten Trichoderma spp. were evaluated for their antibacterial and nematicidal potential against phytopathogenic bacteria Ralstonia solanacearum, Xanthomonas compestris and plant parasitic nematode Meloidogyne incognita. Five different growth media were evaluated for the production of SMs. It was shown that SMs of different Trichoderma spp. obtained on different growth media were different in the degree of their bioactivity. Comparison of five growth media showed that SMs produced on solid wheat and STP media gave higher antibacterial activity. SMs of T. pseudoharzianum (T113) obtained on solid wheat media were more effective against the studied bacteria followed by SMs from T. asperelloides (T136), T. pseudoharzianum (T129) and T. pseudoharzianum (T160). Scanning electron microscopy (SEM) was further conducted to observe the effect of SMs on bacterial cell morphology. As evident from the SEM, SMs produced severe morphological changes, such as rupturing of the bacterial cell walls, disintegration of cell membrane and cell content leaking out. SMs from T. viridae obtained on liquid STP and solid wheat media showed the highest percent of M. incognita juveniles (J2s) mortality and inhibition in egg hatching of M. incognita. The results of our study suggest that T. pseudoharzianum (T113) and T. viridae could be selected as an effective candidate for SMs source against phytopathogenic bacteria and M. incognita respectively.

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Inhibitory Activity of Phosphates on Molds Isolated from Foods and Food Processing Plants

Journal of Food Protection ◽

10.4315/0362-028x-68.11.2475 ◽

2005 ◽

Vol 68 (11) ◽

pp. 2475-2479 ◽

Cited By ~ 9

Author(s):

V. B. SUÁREZ ◽

L. FRISÓN ◽

M. Z. de BASÍLICO ◽

M. RIVERA ◽

J. A. REINHEIMER

Keyword(s):

Inhibitory Activity ◽

Sodium Tripolyphosphate ◽

Food Sources ◽

Aspergillus Ochraceus ◽

Plate Count ◽

Acidic Ph ◽

Ph Values ◽

Neutral Ph ◽

Plate Count Agar ◽

Processing Plants

Six commercial phosphates were evaluated for inhibition of the growth of 17 molds isolated from food sources. The assays were performed at neutral and natural (without pH adjustment) pH values, and the molds were streaked on plate count agar with added phosphates. Phosphate concentrations of 0.1, 0.3, 0.5, 1.0, and 1.5% (wt/vol) were used, and the MIC was determined. The resistance of molds to phosphates depended on the species. At a neutral pH, Aspergillus ochraceus and Fusarium proliferatum were resistant to all phosphates at all concentrations assayed, and Byssochlamys nivea, Aureobasidium pullulans, and Penicillium glabrum were most sensitive. The most inhibitory phosphates were those with chain lengths greater than 15 phosphate units and the highest sequestering power. At natural pH values (resulting from dissolving the phosphate in the medium), inhibitory activity changed dramatically for phosphates that produced alkaline or acidic pH in the medium. Phosphates with alkaline pH values (sodium tripolyphosphate of high solubility, sodium tripolyphosphate, and sodium neutral pyrophosphate) were much more inhibitory than phosphates at a neutral pH, but sodium acid pyrophosphate (acidic pH) had decreased inhibitory activity. The results indicate that some phosphates could be used in the food industry to inhibit molds linked to food spoilage.

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Variable effects of nicotine and anabasine on parasitized bumble bees

F1000Research ◽

10.12688/f1000research.6870.1 ◽

2015 ◽

Vol 4 ◽

pp. 880 ◽

Cited By ~ 1

Author(s):

Lukas P. Thorburn ◽

Lynn S. Adler ◽

Rebecca E. Irwin ◽

Evan C. Palmer-Young

Keyword(s):

Secondary Metabolites ◽

Environmental Conditions ◽

Synergistic Effects ◽

Parasite Load ◽

Bumble Bees ◽

Interactive Effects ◽

Constant Darkness ◽

Floral Nectar ◽

Antagonistic Interaction ◽

Crithidia Bombi

Secondary metabolites in floral nectar have been shown to reduce parasite load in two common bumble bee species. Previous studies on the effects of nectar secondary metabolites on parasitized bees have focused on single compounds in isolation; however, in nature, bees are simultaneously exposed to multiple compounds. We tested for synergistic effects of two alkaloids found in the nectar of Nicotiana spp. plants, nicotine and anabasine, on parasite load and mortality in bumble bees (Bombus impatiens) infected with the intestinal parasite Crithidia bombi. Adult worker bees inoculated with C. bombi were fed nicotine and anabasine diet treatments in a factorial design, resulting in four nectar treatment combinations: 2 ppm nicotine, 5 ppm anabasine, 2ppm nicotine and 5 ppm anabasine together, or a control alkaloid-free solution. We conducted the experiment twice: first, with bees incubated under variable environmental conditions (‘Variable’; temperatures varied from 10-35°C); and second, under carefully controlled environmental conditions (‘Controlled’; 27°C incubator, constant darkness). In ‘Variable’, each alkaloid alone significantly decreased parasite loads, but this effect was not realized with the alkaloids in combination, suggesting an antagonistic interaction. Nicotine but not anabasine significantly increased mortality, and the two compounds had no interactive effects on mortality. In ‘Controlled’, nicotine significantly increased parasite loads, the opposite of its effect in ‘Variable’. While not significant, the relationship between anabasine and parasite loads was also positive. Interactive effects between the two alkaloids on parasite load were non-significant, but the pattern of antagonistic interaction was similar to that in the variable experiment. Neither alkaloid, nor their interaction, significantly affected mortality under controlled conditions. Our results do not indicate synergy between Nicotiana nectar alkaloids; however, they do suggest a complex interaction between secondary metabolites, parasites, and environmental variables, in which secondary metabolites can be either toxic or medicinal depending on context.

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