Zhuang Z et al. (2014) Plant Foods Hum Nutr "The lifespan-extending effects of Nymphaea hybrid root extract in the nematode Caenorhabditis elegans."

Lv T, Zhuang Z, Li M, Xue T, Zhang W, Zhang Y, Liu H, Yang L

[Plant Foods Hum Nutr, 2014]

Nymphaea hybrid, a water lily from the Nymphaeaceae family, has been found to exhibit some in vivo beneficial effects. In the present study we investigated the lifespan-extending effects of Nymphaea hybrid root extract in the nematode Caenorhabditis elegans. We found that Nymphaea hybrid root extract significantly extended the lifespan of C.elegans and improved its locomotion during aging. Moreover, Nymphaea hybrid root extract increased the resistance of C.elegans to both heat stress and oxidative stress. We found that the ability of Nymphaea hybrid root extract to increase lifespan was independent of its antimicrobial effects and was probably associated with its effects on the reproduction of C.elegans. In addition, the lifespan-extending effects of Nymphaea hybrid root extract were found to be dependent on the insulin/IGF signaling pathway. We also found that total flavones of Nymphaea hybrid could increase survival of C.elegans in both normal and adverse conditions, indicating that total flavones comprise the major fractions with lifespan-extending effects. Therefore, Nymphaea hybrid root extract has lifespan-extending effects in C.elegans and could be developed as a functional food.

Pena-Espinoza M et al. (2020) Vet Parasitol "Anthelmintic and metabolomic analyses of chicory (Cichorium intybus) identify an industrial by-product with potent in vitro antinematodal activity."

Valente AH, Simonsen HT, Thamsborg SM, Bornancin L, Lopez-Munoz R, Williams AR, Pena-Espinoza M

[Vet Parasitol, 2020]

Chicory (Cichorium intybus) is a bioactive forage rich in sesquiterpene lactones (SLs) with reported in vitro and in vivo anthelmintic activity in livestock. However, the on-farm adoption of chicory as an anthelmintic crop is limited and may be facilitated by using standardised industrial chicory material. Chicory root pulp is a by-product obtained from industrial chicory roots after inulin extraction and can potentially retain SLs. However, SL content and associated anthelmintic activity of chicory root pulp have not been investigated. Here, we evaluated the anthelmintic activity of SL-enriched extracts from chicory root pulp and forage chicory, and used untargeted metabolomics and molecular networking to identify potential anthelmintic molecules. Six different sources of chicory material were used: fresh chicory root pulp (from industrial chicory roots C. intybus var. sativum; "Root Pulp"), fresh leaves from chicory cv. Spadona (sampled on four occasions) and fresh leaves from chicory cv. Choice. The resulting extracts were tested for anthelmintic activity against the free-living nematode Caenorhabditis elegans and the pig nematode Ascaris suum. The cytotoxicity of the chicory extracts was evaluated on mammalian (Vero) cells. In the C. elegans assays, the Root Pulp was the most potent extract and induced paralysis in >95% of worms exposed to >250 g extract/mL (EC₅₀=64.2g/mL). In the A. suum assays, the Root Pulp was also the most potent chicory extract to inhibit worm motility (EC₅₀ = 87.6 g/mL), followed closely by two of the Spadona leaf extracts (EC₅₀=89.8 g/mL and 112.2 g/mL) The Root Pulp extract had the lowest cytotoxicity of all tested extracts towards mammalian cells, with a selectivity index of 5.37. Untargeted metabolomics revealed that chicory Root Pulp had a markedly different chemical profile in comparison with forage chicory extracts. Molecular networking confirmed several SLs and SL-derivatives mainly present in chicory root pulp, that may be responsible of its potent anti-parasitic activity. Bioactivity-based molecular networking of chicory root pulp and the most potent forage chicory extracts revealed a high predicted anthelmintic score for the guaianolide SL 11,13-dihydro-lactucopicrin. In conclusion, chicory root pulp showed potent and selective in vitro anthelmintic activity against C. elegans and A. suum, with low cytotoxicity in mammalian cells. The promising anthelmintic activity of chicory root pulp should be confirmed in vivo to further explore the potential of this agro-industrial by-product as a nutraceutical anthelmintic for livestock and as novel source of anti-parasitic compounds.

Ohtani K et al. Z Naturforsch C "Nematicidal activities of 4-hydroxyphenylacetic acid and oidiolactone D produced by the fungus Oidiodendron sp."

Ohtani K, Kawano T, Kimura Y, Shimada A, Fujioka S

[Z Naturforsch C]

Two nematicides, 4-hydroxyphenylacetic acid (4-HPA) (1) and oidiolactone D (2), were isolated from cultures of the fungus Oidiodendron sp., and their structures were identified by spectroscopic analyses. Compound 2 showed nematicidal activities against the root-lesion nematode, Pratylenchus penetrans, and the pine wood nematode, Bursaphelenchus xylophilus. Compound 1 was also active against these two nematodes but to a lesser extent.

Kimpinski J (1975) Plant Disease Reporter "Nematodes associated with vegetables in Prince Edward Island Canada."

Kimpinski J

[Plant Disease Reporter, 1975]

Twenty-five genera of nematodes were identified in six vegetable crops (carrot, pea, broccoli, rutabaga, Brussels sprouts, cauliflower) at fifty-six locations in Prince Edward Island (P.E.I.). Root lesion nematodes, Pratylenchus penetrans, were found in the soil at all locations and accounted for about 19% of the total nematode fauna. Meloidogyne hapla were recovered in only a few samples in low numbers, as were nematodes in the order Dorylaimida which accounted for about 5% of the total population. Non-stylet bearing nematodes made up 55% of the total and most of these were in two genera, Caenorhabditis spp. and Cephalobus spp. Carrot soils harbored the highest number of root lesion nematodes and pea soils had the least; 4726 and 547/kg of dry soil, respectively. Pea roots, however, had 2647/g dry root of these nematodes. No root lesion or other endoparasitic nematodes were recovered from the tap roots of carrots or from rutabagas. Some carrot and pea fields appeared to have lower than average yields where root lesion nematodes were recovered from soil and roots in very high numbers.

Michael S. Voegtline et al. (2007) International Worm Meeting "Induced resistance against Meloidogyne incognita infection and egg production via transfection of modified Bacillus thurengiensis (Bt) crystal toxin genes and expression in tomato hairy roots."

Senait Bekele, Anderson Tan, Michael S. Voegtline, Xiang-qian Li, Raffi V. Aroian

[International Worm Meeting, 2007]

To confer resistance against the root gall nematode Meloidogyne incognita, a study was performed to introduce Bacillus thuringiensis (Bt) crystal protein toxin genes into tomato plant (Lycopersicon esculentum var. Rutgers select) hairy roots. Crystal toxin gene sequences were altered to allow plant expression and in some cases also included unique intron sequences to aid in protein expression. Genes were inserted into the pBluscript in concert with a double 35S plant promoter and kanamycin resistance. The vector was used to transform the plant pathogenic bacterium Agrobacterium rhizogenes. The transformed Agrobacterium was used to induce the toxin genes into plants by co-cultivation with tomato cotyledons. Hairy root lines were selected via kanamycin resistance and once established, root extracts were tested for relative expression of crystal toxin by western blot analysis using a polyclonal detection sera specific for each toxin. Induced resistance against the root gall nematode was examined by hairy root challenge against a load of J2 stage parasitic nematodes. Subsequent enumeration of total egg masses (EM), total sites of infection (INF) and total calculated eggs (TE) per root plate were used to determine resistance against nematode infections. Results of these studies will be discussed. Data suggests that some Bt crystal proteins have excellent potential to control plant parasitic nematode (PPN) infections in transgenic plants.

Sakoguchi H et al. (2016) Biosci Biotechnol Biochem "Screening of biologically active monosaccharides: growth inhibitory effects of d-allose, d-talose, and l-idose against the nematode Caenorhabditis elegans."

Izumori K, Yoshihara A, Sakoguchi H, Sato M

[Biosci Biotechnol Biochem, 2016]

We compared the growth inhibitory effects of all aldohexose stereoisomers against the model animal Caenorhabditis elegans. Among the tested compounds, the rare sugars d-allose (d-All), d-talose (d-Tal), and l-idose (l-Ido) showed considerable growth inhibition under both monoxenic and axenic culture conditions. 6-Deoxy-d-All had no effect on growth, which suggests that C6-phosphorylation by hexokinase is essential for inhibition by d-All.

Cheng Y et al. (2016) PLoS One "Soil Nitrogen Status Modifies Rice Root Response to Nematode-Bacteria Interactions in the Rhizosphere."

Jiang Y, Li H, Wu Y, Cheng Y, Valentine TA

[PLoS One, 2016]

It has been hypothesized that faunal activity in the rhizosphere influences root growth via an auxin-dependent pathway. In this study, two methods were used to adjust nematode and bacterial populations within experimental soils. One is "exclusion", where soil mixed with pig manure was placed in two bags with different mesh sizes (1mm and 5m diameter), and then surrounded by an outer layer of unamended soil resulting in soil with a greater populations of bacterial-feeding nematodes (1mm) and a control treatment (5m). The second method is "inoculation", whereby autoclaved soil was inoculated with bacteria (E. coli and Pseudomonas) and Nematodes (Cephalobus and C. elegans). In order to detect the changes in the rice's perception of auxin under different nutrient and auxin conditions in the presence of soil bacterial-feeding nematodes, responses of soil chemistry (NH4+, NO3- and indole acetic acid (IAA)), rice root growth and the expression of an auxin responsive gene GH3-2 were measured. Results showed that, under low soil nutrient conditions (exclusion), low NO3- correlated with increased root branching and IAA correlated with increased root elongation and GH3-2 expression. However, under high soil nutrient conditions (inoculation), a high NH4+ to NO3- ratio promoted an increase in root surface area and there was an additional influence of NH4+ and NO3- on GH3-2 expression. Thus it was concluded that soil bacterial-feeding nematodes influenced soil nutritional status and soil IAA content, promoting root growth via an auxin dependent pathway that was offset by soil nitrogen status.

Sakoguchi H et al. (2016) Bioorg Med Chem Lett "Growth inhibitory effect of d-arabinose against the nematode Caenorhabditis elegans: Discovery of a novel bioactive monosaccharide."

Shintani T, Izumori K, Sato M, Sakoguchi H, Okuma K, Yoshihara A

[Bioorg Med Chem Lett, 2016]

Biological activities of unusual monosaccharides (rare sugars) have largely remained unstudied until recently. We compared the growth inhibitory effects of aldohexose stereoisomers against the animal model Caenorhabditis elegans cultured in monoxenic conditions with Escherichia coli as food. Among these stereoisomers, the rare sugar d-arabinose (d-Ara) showed particularly strong growth inhibition. The IC50 value for d-Ara was estimated to be 7.5mM, which surpassed that of the potent glycolytic inhibitor 2-deoxy-d-glucose (19.5mM) used as a positive control. The inhibitory effect of d-Ara was also observed in animals cultured in axenic conditions using a chemically defined medium; this excluded the possible influence of E. coli. To our knowledge, this is the first report of biological activity of d-Ara. The d-Ara-induced inhibition was recovered by adding either d-ribose or d-fructose, but not d-glucose. These findings suggest that the inhibition could be induced by multiple mechanisms, for example, disturbance of d-ribose and d-fructose metabolism.

Yoshihara A et al. (2019) Bioorg Med Chem Lett "Growth inhibition by 1-deoxy-d-allulose, a novel bioactive deoxy sugar, screened using Caenorhabditis elegans assay."

Sakoguchi H, Fleet GWJ, Izumori K, Shintani T, Sato M, Yoshihara A

[Bioorg Med Chem Lett, 2019]

The biological activities of deoxy sugars (deoxy monosaccharides) have remained largely unstudied until recently. We compared the growth inhibition by all 1-deoxyketohexoses using the animal model Caenorhabditis elegans. Among the eight stereoisomers, 1-deoxy-d-allulose (1d-d-Alu) showed particularly strong growth inhibition. The 50% inhibition of growth (GI₅₀) concentration by 1d-d-Alu was estimated to be 5.4mM, which is approximately 10 times lower than that of d-allulose (52.7mM), and even lower than that of the potent glycolytic inhibitor, 2-deoxy-d-glucose (19.5mM), implying that 1d-d-Alu has a strong growth inhibition. In contrast, 5-deoxy- and 6-deoxy-d-allulose showed no growth inhibition of C. elegans. The inhibition by 1d-d-Alu was alleviated by the addition of d-ribose or d-fructose. Our findings suggest that 1d-d-Alu-mediated growth inhibition could be induced by the imbalance in d-ribose metabolism. To our knowledge, this is the first report of biological activity of 1d-d-Alu which may be considered as an antimetabolite drug candidate.

Katane M et al. (2020) Biochim Biophys Acta Proteins Proteom "Biochemical characterization of d-aspartate oxidase from Caenorhabditis elegans: Its potential use in the determination of free D-glutamate in biological samples."

Katane M, Sekine M, Nakayama K, Homma H, Kuwabara H, Saitoh Y, Miyamoto T

[Biochim Biophys Acta Proteins Proteom, 2020]

d-Aspartate oxidase (DDO) is a flavin adenine dinucleotide (FAD)-containing flavoprotein that stereospecifically acts on acidic D-amino acids (i.e., free d-aspartate and D-glutamate). Mammalian DDO, which exhibits higher activity toward d-aspartate than D-glutamate, is presumed to regulate levels of d-aspartate in the body and is not thought to degrade D-glutamate in vivo. By contrast, three DDO isoforms are present in the nematode Caenorhabditis elegans, DDO-1, DDO-2, and DDO-3, all of which exhibit substantial activity toward D-glutamate as well as d-aspartate. In this study, we optimized the Escherichia coli culture conditions for production of recombinant C. elegans DDO-1, purified the protein, and showed that it is a flavoprotein with a noncovalently but tightly attached FAD. Furthermore, C. elegans DDO-1, but not mammalian (rat) DDO, efficiently and selectively degraded D-glutamate in addition to d-aspartate, even in the presence of various other amino acids. Thus, C. elegans DDO-1 might be a useful tool for determining these acidic D-amino acids in biological samples.