scholarly journals Nematicidal activity of a biopolymer chitosan at different molecular weights against root-knot nematode, Meloidogyne incognita

2012 ◽  
Vol 48 (No. 4) ◽  
pp. 170-178 ◽  
Author(s):  
M.S. Khalil ◽  
M.E.I. Badawy
Keyword(s):  
Molecular Weight ◽  
Meloidogyne Incognita ◽  
Nematicidal Activity ◽  
Egg Mass ◽  
Low Molecular Weight ◽  
Root Knot Nematode ◽  
Molecular Weights ◽  
Tomato Seedlings ◽  
Low Molecular Weight Chitosan

The nematicidal activity of four molecular weights (2.27 &times; 10<sup>5</sup>, 3.60 &times; 10<sup>5</sup>, 5.97 &times; 10<sup>5</sup>, and 9.47 &times; 10<sup>5</sup> g/mol) of a biopolymer chitosan was assayed against the root-knot nematode, Meloidogyne incognita, in vitro and in pot experiments. In laboratory assays, the nematode mortality was significantly influenced by exposure times and chitosan molecular weight. Low molecular weight chitosan (2.27 &times; 10<sup>5</sup> g/mol) was the most effective in killing the nematode with EC<sub>50</sub> of 283.47 and 124.90 mg/l after 24 and 48 h of treatment, respectively. In a greenhouse bioassay, all the compounds mixed in soil at one- and five-fold concentrations of the LC<sub>50</sub> value significantly reduced population, egg mass, and root galling of tomato seedlings compared with the untreated control. In general, the nematicidal activity of these compounds was increased dramatically with a decrease in the molecular weight. The results suggest that the chitosan at low molecular weight may serve as a natural nematicide

scholarly journals Evaluation of various seed extracts for their nematicidal efficacies against root nematode, Meloidogyne incognita

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Zubair Rehman Nengroo ◽  
Zeshan Umer Shah ◽  
Adil Shafi Ganie ◽  
Mohammad Danish
Keyword(s):  
Meloidogyne Incognita ◽  
Nematicidal Activity ◽  
Egg Mass ◽  
The Novel ◽  
Root Knot Nematode ◽  
Isolation And Purification ◽  
Bunium Persicum ◽  
Bioactive Substance ◽  
Seed Extracts

AbstractThe current study was assumed to identify the novel nematicidal activity of chloroform and methanol (50:50, v/v) seed extracts of eight medicinally important plants viz. Abrus precatorius Linn., Amaranthus virdis Linn., Bunium persicum Boiss., Dioscorea deltoidea Wall. Ex Griseb., Teraxacum officinale Weber., Malva neglecta Wall., Podophylum hexandrum Royle and Robina pseudoacacia Linn. using the root-knot nematode Meloidogyne incognita in in vitro and greenhouse experiments. At 72 h exposure, the extracts were found to be highly nematostatic, where nematodes were completely paralyzed at 12 and 48 h of exposure. However, dominant mortality was observed by T. officinale 93.67% and B. persicum 89.66% seed extracts at 72 h. In greenhouse method, extracts of T. officinale and B. persicum extracts were found to be most potent in reducing number of galls (1.76 and 2.37) and number of egg masses (0.06 and 2.18) respectively as compared to inoculated control. The root knot index of all extracts varied between 1–3 and egg mass index 0–3 as compared to control. This study suggested that seed extracts of these plants can be used for the management of M. incognita and could be used in replacement of synthetic nematicides upon further isolation and purification of bioactive substance responsible for nematicidal activity.

scholarly journals Anticoagulant Properties of a Green Algal Rhamnan-type Sulfated Polysaccharide and Its Low-molecular-weight Fragments Prepared by Mild Acid Degradation

Marine Drugs ◽  
2018 ◽  
Vol 16 (11) ◽  
pp. 445 ◽  
Author(s):  
Xue Liu ◽  
Peng Du ◽  
Xiao Liu ◽  
Sujian Cao ◽  
Ling Qin ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Anticoagulant Activity ◽  
Sulfated Polysaccharide ◽  
Low Molecular Weight ◽  
Thrombin Time ◽  
Acid Degradation ◽  
Molecular Weights ◽  
Green Algal

The active sulfated polysaccharide from seaweed possesses important pharmaceutical and biomedical potential. In the study, Monostroma sulfated polysaccharide (MSP) was obtained from Monostroma angicava, and the low-molecular-weight fragments of MSP (MSP-Fs: MSP-F1–MSP-F6) were prepared by controlled acid degradation. The molecular weights of MSP and MSP-F1–MSP-F6 were 335 kDa, 240 kDa, 90 kDa, 40 kDa, 24 kDa, 12 kDa, and 6.8 kDa, respectively. The polysaccharides were sulfated rhamnans that consisted of →3)-α-l-Rhap-(1→ and →2)-α-l-Rhap-(1→ units with partial sulfation at C-2 of →3)-α-l-Rhap-(1→ and C-3 of →2)-α-l-Rhap-(1→. Anticoagulant properties in vitro of MSP and MSP-F1–MSP-F6 were evaluated by studying the activated partial thromboplastin time, thrombin time, and prothrombin time. Anticoagulant activities in vivo of MSP and MSP-F4 were further evaluated; their fibrin(ogen)olytic activities in vivo and thrombolytic properties in vitro were also assessed by D-dimer, fibrin degradation products, plasminogen activator inhibitior-1, and clot lytic rate assays. The results showed that MSP and MSP-F1–MSP-F4 with molecular weights of 24–240 kDa had strong anticoagulant activities. A decrease in the molecular weight of MSP-Fs was accompanied by a decrease in the anticoagulant activity, and higher anticoagulant activity requires a molecular weight of over 12 kDa. MSP and MSP-F4 possessed strong anticoagulant activities in vivo, as well as high fibrin(ogen)olytic and thrombolytic activities. MSP and MSP-F4 have potential as drug or helpful food supplements for human health.

Biocontrol potential of Lysobacter antibioticus HS124 against the root-knot nematode, Meloidogyne incognita, causing disease in tomato

Nematology ◽  
2013 ◽  
Vol 15 (5) ◽  
pp. 545-555 ◽  
Author(s):  
Yong Seong Lee ◽  
Muhammad Anees ◽  
Hae Nam Hyun ◽  
Kil Yong Kim
Keyword(s):  
Meloidogyne Incognita ◽  
Bacterial Strain ◽  
Tap Water ◽  
Nematicidal Activity ◽  
Root Knot Nematode ◽  
Lytic Enzymes ◽  
Pot Experiments ◽  
Hydroxyphenylacetic Acid

Lysobacter antibioticus HS124 is an antagonistic bacterial strain that was previously isolated from the rhizosphere soil of pepper and showed an enhanced ability to produce lytic enzymes as well as an antibiotic that was identified as 4-hydroxyphenylacetic acid (4-HPAA). In the present study, nematicidal activity of the strain and 4-HPAA against the root-knot nematode, Meloidogyne incognita, causing disease in tomato was investigated in both in vitro and in vivo conditions. For this purpose, adding different concentrations of culture filtrate, crude extract collected from extraction with ethyl acetate and 4-HPAA, in 24-well plates containing ca 500 eggs or 300 second-stage juveniles (J2), significantly decreased the rate of nematode hatch and caused higher mortality of J2 compared with the control treatments. Nematicidal activity of the bacterial strain was further confirmed by conducting pot experiments in which tomato plants were inoculated with M. incognita and the HS124 culture (BC). The control pots were treated with commercial nematicide (CN, 5% Ethoprophos), tap water (TW) or the non-inoculated bacterial culture medium (BCM). In these pot experiments, results demonstrated a strong antagonistic potential of L. antibioticus HS124 against M. incognita where the disease was significantly reduced in the pots treated with BC as compared to TW or BCM. Furthermore, the shoot fresh weight was also increased significantly, which may be attributed to the disease control ability of the strain. Hence, L. antibioticus HS124 may be further developed as a potential biocontrol of root knot nematode in the field.

scholarly journals Investigating the in vitro and in vivo nematicidal performance of structurally related macrolides against the root-knot nematode, Meloidogyne incognita

2019 ◽  
Vol 12 (1) ◽  
pp. 24-37
Author(s):  
M.A. Radwan ◽  
A.S.A. Saad ◽  
H.A. Mesbah ◽  
H.S. Ibrahim ◽  
M.S. Khalil
Keyword(s):  
Meloidogyne Incognita ◽  
Root Length ◽  
Egg Mass ◽  
Root Knot Nematode ◽  
Egg Hatching ◽  
Shoot Height ◽  
Egg Masses ◽  
New Family

Summary Avermectins and spinosyns are structurally related natural products of microbial origin and belong to a new family of macrolides which are active against a vast array of invertebrate pests. In the present study, the effects of four members of macrolides; abamectin (ABM), emamectin benzoate (EMB), spinosad (SPI) and spinetoram (SPIT), on Meloidogyne incognita were investigated under in vitro and in vivo conditions. All compounds reduced egg hatching and led to high mortality of the nematode second-stage juveniles (J2). ABM showed the maximum rate of egg hatching inhibition and J2 mortality while SPIT recorded the minimum. All treatments reduced the number of galls, egg masses, eggs/egg mass in roots and J2 in the soil when compared to the control. Based on the 10 folds of the 24 h-LC50 values of J2 mortality in vitro, EMB and ABM exhibited higher percent reduction in galls (79.68 and 71.45%), egg masses (75.19 and 70.54%), eggs/egg mass (60.49 and 40.91%) and J2 in the soil (90.31 and 86.54%), respectively, compared to SPI and SPIT. Significant increase in tomato shoot height occurred in all biopesticides (10 folds) and SPIT (20 folds). SPI at 10 folds of the 24 h-LC50 values of J2 mortality in vitro, significantly increased root length while ABM at 50 folds and SPIT at 20 folds decreased root length by 5.15% and 5.88%, respectively, compared to the untreated inoculated plants. In all treatments, the dry shoot and root weights increased, compared to the untreated control. Our findings suggest that these macrolides have the ability to regulate nematode population densities and may be an alternative to classical nematicides.

scholarly journals Nematicidal Activity of the Essential Oil of Three Varieties of Tagetes minuta from Argentina

2017 ◽  
Vol 12 (5) ◽  
pp. 1934578X1701200
Author(s):  
Yamile Massuh ◽  
Angel Cruz-Estrada ◽  
Azucena González-Coloma ◽  
Marta S. Ojeda ◽  
Julio A. Zygadlo ◽  
...  
Keyword(s):  
Lethal Dose ◽  
Nematicidal Activity ◽  
Root Knot Nematode ◽  
Egg Hatching ◽  
Tomato Seedlings ◽  
Tagetes Minuta ◽  
In Vivo Tests ◽  
New Varieties

Essential oils composition of three Tagetes minuta varieties and a wild population (WP) from Argentina and their in vitro and in vivo nematicidal activity against root-knot nematode, Meloidogyne javanica, are described. All T. minuta EOs tested were very active against nematode juveniles (J2), but the strongest nematicidal effects were exhibited by the TmV3 variety oil, characterized by a high content of ( E)-ocimenone. High nematode egg hatching suppression (> 90%) was induced by TmV3 EO after five days of incubation. In vivo tests on tomato seedlings showed a significant reduction of infection rate of M. javanica J2 treated with TmV3 and WP oils at sub lethal dose. Therefore, EOs from chemically stable new varieties of T. minuta could be environmentally friendly nematicidal agents.

The effect of low molecular weight Chitosan on bone resorption in vitro and in vivo

Phytomedicine ◽  
1999 ◽  
Vol 6 (5) ◽  
pp. 305-310 ◽  
Author(s):  
Huiying Li ◽  
Tatsuro Miyahara ◽  
Yasuhiro Tezuka ◽  
Makoto Watanabe ◽  
Nobuo Nemoto ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Bone Resorption ◽  
Low Molecular Weight ◽  
Low Molecular Weight Chitosan

scholarly journals Nematicidal Activity of Monoterpenoids Against the Root-Knot Nematode Meloidogyne incognita

2010 ◽  
Vol 100 (2) ◽  
pp. 199-203 ◽  
Author(s):  
Sergio Echeverrigaray ◽  
Jucimar Zacaria ◽  
Ricardo Beltrão
Keyword(s):  
Meloidogyne Incognita ◽  
Nematicidal Activity ◽  
Root Knot Nematode ◽  
High Concentration ◽  
Tomato Plants ◽  
Pot Experiments ◽  
Low Concentrations ◽  
Dose Dependent ◽  
Dose Dependent Effect

Nematicidal activity of 22 monoterpenoids were evaluated in vitro and in pot experiments. Twenty of the twenty-two monoterpenoids significantly reduced hatching, and 11 reduced J2 mobility of the root-knot nematode Meloidogyne incognita at a concentration of 250 mg/liter. In general, compounds with hydroxyl and carbonyl groups exhibited higher nematicidal activity than other terpenoids. Borneol, carveol, citral, geraniol, and α-terpineol showed the highest nematicidal activity among the in vitro tested monoterpenoids. These compounds exhibited a dose dependent effect, and drastically reduced eggs hatching and J2 viability at low concentrations. These monoterpenoids, at 100 and 250 mg/kg concentration, diminished root galling of tomato plants in pot experiments. The results suggest that the selected monoterpenoids, and essential oils with high concentration of these compounds, are potential nematicides against Meloidogyne.

scholarly journals PREPARATION AND CHARACTERIZATION OF LOW MOLECULAR WEIGHT CHITOSAN WITH DIFFERENT DEGREES OF DEACETYLATION BY THE ACID HYDROLYSIS METHOD

2021 ◽  
pp. 153-164
Author(s):  
NAWZAT D. AL-JBOUR ◽  
M. D. H. BEG ◽  
JOLIUS GIMBUN ◽  
A. K. M. MOSHIUL ALAM
Keyword(s):  
Molecular Weight ◽  
Acid Hydrolysis ◽  
Water Solubility ◽  
Skeletal Structure ◽  
Low Molecular Weight ◽  
Molecular Weights ◽  
Hydrolysis Method ◽  
Significant Difference ◽  
Low Molecular Weight Chitosan ◽  
Pharmaceutical Industries

Objective: The objective of this research is to prepare Low Molecular Weight Chitosan (LMWC) by the acid hydrolysis method, using dilute hydrochloric acid (2M). LMWC has superior properties compared to the High Molecular Weight Chitosan (HMWC), especially in terms of water solubility, antibacterial and antifungal properties. These could open new potential applications for LMWC in sectors such as the cosmetics, food, and pharmaceutical industries. Methods: In this work, the acid hydrolysis method was used to produce LMWC with different molecular weights starting from 500 kDa and 93% degree of deacetylations (DDA). The molecular weights of the produced grades were determined by applying Mark-Houwink equation while the %DDA was determined and verified by the use of the 1st derivative UV method and 1HNMR method, respectively. The depolymerization reactions were carried out with different time intervals to produce totally deacetylated LMWC of 30 kDa, 15 kDa, and 7.5 kDa. The LMWC was characterized by FTIR, XRD, and DSC to evaluate the functionality, microstructure and thermal properties. Results: The FTIR spectra revealed that there is no significant difference in the main skeletal structure of the LMWC and HMWC. On the other hand, the XRD and DSC results showed that the LMWC of different molecular weights and degrees of deacetylation are of semi-crystalline structure, similar to the HMWC. Conclusion: The obtained results showed that the used acid hydrolysis procedure can produce LMWC grades of desired specifications, yields, and quality which are suitable for use in different applications.

Sign in / Sign up

Export Citation Format

Share Document