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Previous studies showed that the extract of Amaranthus retroflexus could significantly enhance the heat stress resistance of wheat seedlings, but the active components responsible for this activity are still unknown. In this study, five compounds were isolated from the roots of A. retroflexus by using a bioassay-guided method. They were identified as p-hydroxybenzoic acid (1), 14-hydroxymyristic acid (2), p-methoxybenzoic acid (3), 3-hydroxyacetyl-indole (4), and 3-indole formaldehyde (5) by nuclear magnetic resonance spectroscopy and mass spectrometry analysis. p-Hydroxybenzoic acid, p-methoxybenzoic acid, and 14-hydroxymyristic acid could enhance the tolerance of wheat seedlings to heat stress with p-methoxybenzoic acid showing the highest activity. Under high-temperature stress, the fresh weight and length of aboveground, and root length of the wheat seedlings treated with 100 μg/mL p-methoxybenzoic acid increased by 56.44%, 30.03%, and 38.71% compared with the control. The changes in relevant physiological and biochemical indicators were determined in wheat seedlings treated with 50 μg/mL p-methoxybenzoic acid and subjected to high-temperature stress for 1, 3, 5, and 7 days. The results showed that the malondialdehyde content in the plant decreased by 32.59%, 50.27%, 57.53%, and 33.64% compared with the control, respectively. The proline content increased by 28.57%, 50.00%, and 29.87% on days 1, 3, and 5, respectively, and then decreased by 5.16% on day 7. The soluble sugar content increased by 39.76%, 35.93%, 41.33%, and 12.50%. Superoxide dismutase enzyme activity increased by 39.48%, 41.63%, 26.09% and 25.27%. Peroxidase enzyme activity increased by 11.19%, 32.05%, 32.54%, and 26.90%. Catalase enzyme activity increased by 35.62%, 50.97%, 22.82%, and 25.89%, respectively. Collectively, p-methoxybenzoic acid can significantly improve wheat resistance to high-temperature stress. [ABSTRACT FROM AUTHOR]

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Ailanthone, a quassinoid isolated from Ailanthus altissima, is a promising candidate for natural herbicides. The herbicidal mechanism of action of ailanthone was preliminarily investigated in this study by the measurement of physiological indicators and germination test in a dish. Ailanthone had no effect on the capacity of seeds water uptake. Ailanthone strongly inhibited plant cells division with a mitotic index of 0.48% at the concentration of 1.00 μg/mL, as compared to 5.85% in the clear water control, and it could cause cell division malformation. Combined information such as enzymes activity assays of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) activity implied that the antioxidant capacity of plants could be improved by ailanthone. Reactive oxygen species (ROS) staining indicated that the outbreak of ROS could be induced with the concentration of 0.10 μg/mL ailanthone. The results of cell mortality showed that the presence of ailanthone could cause a certain percentage of cell inactivity. Ailanthone showed herbicidal activity by affecting multiple targets. Ailanthone could effectively inhibit plant cells division and the accumulation of ROS. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Eight compounds W1-1-W1-8 were isolated from the secondary metabolites of Cylindrocarpon olidum W1, which is an endophytic fungus from Euonymus japonica, by silica gel column chromatography and pre-HPLC techniques. Based on the 1H NMR and 13C NMR and HRMSMS data, as well as the published literatures, these chemicals were identified as Ilicicolin A (W1-1), 5-Chlorocolletorin B (W1-2), Ilicicolin B (W1-3), Deacetylchloronectrin (W1-4), Ilicicolin C (W1-5), Ascochlorin (W1-6), Cylindrol A4 (W1-7) and Cylindrol B (W1-8). The obtained Ascochlorin and its analogues showed strong antibacterial activities against Ralstonia solanacearum, with minimum inhibitory concentrations (MICs) of 6.25, 3.13, > 100, 3.13, 6.25, 12.5, 25 and 25 μg/mL, respectively. Compounds W1-2, W1-4 and W1-5 could also effectively inhibit the mycelial growth of plant pathogenic fungi Botrytis cinerea and Sclerotinia sclerotiorum. Their medium inhibitory concentrations (IC50) against B. cinerea were 36.45, 21.60 and 26.69 μg/mL, respectively. Their IC50 values against S. sclerotiorum were 20.21, 16.79 and 12.11 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To discover insecticidal ingredients from natural products, Streptomyces lateritius CSF09, an endophyte strain was isolated from Eleusine indica (L.) Gaertn. The bioactive compound was isolated from the fermentation broth by techniques of macroporous resin extraction and silica gel column chromatography, and its chemical structure was identified by MS and NMR. The obtained compound was subjected to evaluate its insecticidal activity against the 3rd larvae of Mythimna separate and adults of Musca domestica. The results indicated that the insecticidal ingredient produced by the strain was 4- methoxysalicylaldehyde with the yield of approximately 13 mg/L. 4-Methoxysalicylaldehyde showed contact toxicity against both M. separate and M. domestica. The LD50 value of M. domestica was 1.51 μg/fly. 4-Methoxysalicylaldehyde showed weak toxicity against M. separate, and the mortality rate was only 36.6% after the treatment of 10 μg/larvae. The outstanding characteristic of the insecticidal activity of 4-methoxysalicylaldehyde was quick-acting with the KT50 in most treatments less than 5 min. This investigation suggested that 4-methoxysalicylaldehyde has the potential to be developed as a health insecticide. [ABSTRACT FROM AUTHOR]

Two antimicrobial compounds, G13 and G19, were isolated from fermentation broth of actinomycete Streptomyces flavofuscus G1, an endophyte isolated from Euonymus japonicas. The structures of G13 and G19 were identified as phencomycin(G13)and 4'-deacetyl-(-)-griseusin A(G19), respectively, based on the 1H NMR and 13C NMR and ESI-MS data, as well as the published literatures. G19 showed strong antibacterial activity against Xanthomonas oryzae pv. oryzae,Pseudomonas aeruginosa,Bacillus cereus and Staphylococcus aureuse, with minimum inhibitory concentration (MIC) value of 1.56 μg/mL. In addition, G19 could also effectively inhibit the mycelial growth of plant pathogenic fungi Valsa mali and Fusarium graminearum, and the IC50 values were 14.70 and 24.35 μg/mL, respectively. G13 exhibited strong antifungal activity against the mycelial growth of Sclerotinia sclerotiorum and V. mali, with IC50 values of 5.21 and 4.82 μg/mL, respectively. [ABSTRACT FROM AUTHOR]