1.Optimization of fermentation conditions in shake flask of JA20-1, a VOCs-producing biocontrol bacterium and evaluation of its biocontrol effect against Botrytis cinerea of ginseng.
Yu-Ze ZHANG ; Yan-Cong HU ; Xiu-Xiu WANG ; Cong ZHANG ; Zhong-Hua QU ; Bao-Hui LU ; Xue WANG ; Jie GAO
China Journal of Chinese Materia Medica 2025;50(7):1748-1757
Bacillus mycoides JA20-1 was screened and identified as a biocontrol bacterium with a high capacity for producing volatile organic compounds(VOCs) in the laboratory. This strain had significant inhibitory effects on various postharvest disease pathogens in crops, such as Botrytis cinerea, as well as soil-borne disease pathogens in ginseng, such as Sclerotinia ginseng. In order to accelerate its industrialization process, in this study, single-factor experiments and response surface optimization methods were used. The fermentation medium and fermentation conditions in the shake flask of strain JA20-1 were systematically optimized by using cell production volume as the response variable. Meanwhile, the biocontrol effect of JA20-1 on B. cinerea of ginseng during the storage period was evaluated by using the method of fumigation in a dry dish in vitro. The results indicated that the optimal fermentation medium formulation for strain JA20-1 was as follows: 1% yeast paste, 1% soluble starch, 0.25% K_2HPO_4·3H_2O, and 0.2% NaCl. The optimal fermentation conditions in the shake flask were vaccination size of 3%, culture volume of 50 mL in a 250 mL Erlenmeyer flask, pH of 6.2, fermentation temperature of 34 ℃, shaking speed of 180 r·min~(-1), and incubation time of 18 hours. The bacteria count in the fermentation broth under these conditions reached 2.17 × 10~8 CFU·mL~(-1), which was 6.58 times higher than before. The average control efficacy of the fermentation broth on Botrytis cinerea of ginseng under in vitro fumigation reached 61.70% and 84.04% respectively, when 20 mL and 30 mL per dish were used. The research provided theoretical support and technical foundation for the development and utilization of Bacillus mycoides JA20-1 and the biocontrol of soil-borne diseases in ginseng and postharvest diseases in crops.
Botrytis/drug effects*
;
Fermentation
;
Panax/microbiology*
;
Plant Diseases/prevention & control*
;
Volatile Organic Compounds/metabolism*
;
Bacillus/physiology*
;
Pest Control, Biological/methods*
;
Biological Control Agents/metabolism*
;
Culture Media/chemistry*
2.Screening and identification of a biocontrol strain CXG2-5 against kiwifruit bacterial canker and preparation of microcapsules.
Jing HUANG ; Ruolan YANG ; Xinying LIU ; Zihan ZHANG ; Nana WANG ; Lili HUANG
Chinese Journal of Biotechnology 2025;41(10):3734-3746
To develop biocontrol agents for the control of kiwifruit bacterial canker, we isolated a strain CXG2-5 with inhibitory activity against Pseudomonas syringae pv. actinidiae (Psa), the pathogen of kiwifruit bacterial canker, from the rhizosphere soil of kiwifruit by the plate confrontation test. The strain was identified by morphological observation, physiological and biochemical tests, and molecular biological methods. The indoor control efficacy of the strain was determined by the inoculation of the strain into detached branches with wounds and into leaf discs by vacuum infiltration. The ability of the strain to expand and colonize leaf veins was determined by fluorescent labeling and scanning electron microscopy. Subsequently, the strain was prepared into microcapsules, the field control efficacy of which was evaluated. The strain CXG2-5 was identified as Pseudomonas benzenivorans. It demonstrated good antagonistic activity against Psa, with an inhibition zone diameter of 22 mm and an inhibition rate of 72.7%. The preventive effects of the strain on kiwifruit bacterial canker were better than the therapeutic effects on both detached branches and leaves, with the preventive effects reaching 65% and 92.4%, respectively. The control effect of microcapsules of this strain in the field reached 60.89%, which was slightly lower than that of 20% kasugamycin and higher than that of Bacillus subtilis wettable powder. In conclusion, strain CXG2-5 serves as a candidate for the control of kiwifruit bacterial canker, and the prepared microcapsules have good value for development and application.
Actinidia/microbiology*
;
Plant Diseases/prevention & control*
;
Pseudomonas syringae
;
Pseudomonas/isolation & purification*
;
Capsules
;
Antibiosis
;
Biological Control Agents
;
Pest Control, Biological/methods*
3.Screening of soil biocontrol bacteria and evaluation of their control effects on Fusarium head blight of wheat.
Dongfang WANG ; Xinxin ZHAI ; Chunlin YANG ; Huilan ZHANG ; Jie WU ; Zerong SONG ; Pan ZHAO ; Yu CHI
Chinese Journal of Biotechnology 2025;41(10):3764-3773
Fusarium head blight (FHB), caused by Fusarium graminearum, not only leads to severe yield losses but also poses a threat to food safety due to the mycotoxins produced by the pathogen. Since this disease is preventable but not curable, the current control mainly relies on chemical fungicides, the long-term use of which may lead to pathogen resistance and environmental pollution. To develop green control methods, we screened 13 biocontrol strains from the rhizosphere soil of wheat, among which strain No. 12 (identified as Pythium aphanidermatum) showed significant antifungal effects. In the plate confrontation test, this strain reduced the colony diameter of the pathogen by 69.2% (1.47 mm vs. 4.78 mm in the control group), with an inhibition rate of 77% (P < 0.01). Microscopic observation revealed obvious deformations in the pathogen hyphae, suggesting a lysing effect. The coleoptile experiment further confirmed that the pre-treatment with this strain reduced the incidence rate to 0. These findings provide new candidate strains for the biocontrol of FHB and offer a scientific basis for reducing the use of chemical fungicides and promoting sustainable agricultural development.
Triticum/growth & development*
;
Fusarium/growth & development*
;
Plant Diseases/prevention & control*
;
Soil Microbiology
;
Pest Control, Biological/methods*
;
Pythium/physiology*
;
Biological Control Agents
;
Rhizosphere
;
Fungicides, Industrial
4.Common diseases and drug use characteristics of Chinese herbal medicines and suggestions.
Chang-Gui YANG ; Wei-Ke JIANG ; Ye YANG ; Lan-Ping GUO ; Xiao-Bo ZHANG ; Cheng-Gang ZHANG ; Dan ZHAO ; Hong-Xia ZHANG ; Tao ZHOU
China Journal of Chinese Materia Medica 2023;48(11):2925-2930
Based on the data of 56 kinds of diseases and drug use in 100 kinds of cultivated Chinese herbal medicines, this paper used frequency analysis method to count the types of diseases and their drug use characteristics, and systematically analyzed the status of drug registration and monitoring standards for disease prevention and control of Chinese herbal medicines. The results showed that 14 diseases such as root rot, powdery mildew, and drooping disease were common in the production of Chinese herbal medicines. Among the 99 pesticides reported, 67.68% were chemically synthesized, 23.23% were biological pesticides, and 9.09% were mineral pesticides. Among the reported pesticides, 92.93% of them were low toxic, with relative safety. However, 70% of the production drugs were not registered in Chinese herbal medicines, and the phenomenon of overdose was serious. The current pesticide residue monitoring standards does not match well with production drugs in China. Although the matching degree between Maximum Residue Limit of Pesticide in Food Safety National Standard(GB 2763-2021) and production drugs is more than 50%, there are few varieties of Chinese herbal medicines covered. The matching degree between Chinese Pharmacopoeia(2020 edition), Green Industry Standard of Medicinal Plants and Preparations(WM/T2-2004), and production drugs is only 1.28%. It is suggested to speed up the research and registration of Chinese herbal medicine production and further improve the pesticide residue limit standard combined with the actual production, so as to promote the high-quality development of Chinese herbal medicine industry.
Humans
;
Biological Control Agents
;
Drugs, Chinese Herbal
;
Pesticide Residues
;
Pesticides
5.Common diseases and drug use of Pseudostellaria heterophylla.
Chang-Gui YANG ; Ye YANG ; Lan-Ping GUO ; Xiao-Bo ZHANG ; Gao-Sheng PEI ; Hong-Xia ZHANG ; Gui-Hong ZHU ; Xiao-Feng WU ; Tao ZHOU
China Journal of Chinese Materia Medica 2023;48(12):3281-3286
Pseudostellaria heterophylla in large-scale cultivation needs to apply pesticides to control diseases, and non-standard use of pesticide may cause excessive pesticide residues in medicinal materials, increasing the risk of clinical medication. To accurately monitor the residual pesticides, this paper investigated the drug use during the process of P. heterophylla disease prevention in 25 P. he-terophylla planting enterprises or individual households in Guizhou province. It was found that there were 8 common diseases in P. he-terophylla planting, including leaf spot, downy mildew, virus disease, root rot, dropping disease, purple feather disease, white silk disease, and damping-off disease. Twenty-three kinds of pesticides were used in disease control, mainly chemical synthetic pesticides, accounting for 78.3%, followed by biological pesticides and mineral pesticides, accounting for 13.0% and 8.7%, respectively. The disease prevention and control drugs were all low-toxic pesticides, and there were no varieties banned in the Chinese Pharmacopoeia(2020 edition). However, the pesticides used have not been registered on P. heterophylla, and the excessive use of drugs was serious. The present monitoring of pesticide residues in P. heterophylla is mainly based on traditional pesticides such as organochlorine, organophosphorus, and carbamate, which does not effectively cover the production of drugs and had certain safety risks. It is suggested to speed up the research and registration of drug use in the production of P. heterophylla, increase the use of biological pesticides, and further improve the monitoring indicators of pesticide residues in combination with the actual production of drugs, so as to promote the high-quality development of P. heterophylla industry.
Biological Control Agents
;
Caryophyllaceae
;
Pesticide Residues
;
Pesticides
;
Plants, Medicinal
6.Performance of a selected Trichoderma strain as plant pathogen inhibitor and biofertilizer
Abdul Muizz Al-Azim Abdul-Halim ; Pooja Shivanand ; Hussein Taha
Malaysian Journal of Microbiology 2022;18(4):446-454
Aims:
The application of beneficial microbes is a suitable alternative to synthetic pesticides and fertilizers for agriculture. This study was aimed to evaluate the potential of a selected Trichoderma strain as a biocontrol agent against Rhizoctonia sp. and as a biofertilizer to improve paddy growth.
Methodology and results:
Four Bipolaris strains were identified via DNA barcoding as the cause of brown spot disease, whereas two Rhizoctonia strains were similarly identified as the cause of sheath blight disease in Brunei Darussalam. Eight Trichoderma strains were initially screened using confrontation assay and were found to substantially inhibit the growth of Rhizoctonia sp. Hybrid rice named BDR5 was treated with Trichoderma sp. UBDFM01 and/or Rhizoctonia sp. It was found that the selected strain showed the potential as a biofertilizer by significantly increasing the vigour index I, chlorophyll a, chlorophyll b, total chlorophyll and dry shoot weight of the rice plants. The pathogen negatively affected the plants by significantly reducing the vigour index II, chlorophyll a, chlorophyll a/b ratio, total chlorophyll, and total weight of grains. Trichoderma strain showed the potential as a biocontrol agent by significantly diminishing the negative effects of the pathogen on the chlorophyll a, chlorophyll a/b ratio and total chlorophyll.
Conclusion, significance and impact of study
This study highlights the potential of Trichoderma sp. UBDFM01 as a biocontrol agent against Rhizoctonia sp. and also as a biofertilizer for rice plants. In addition, this study is the first to provide DNA-based evidence of Bipolaris sp. and Rhizoctonia sp. as the fungi that caused rice diseases in Brunei Darussalam.
Trichoderma
;
Biological Control Agents
;
Fertilizers--microbiology
7.Anti-inflammatory target prediction of Gentianae Radix et Rhizoma based on network pharmacology and construction of a bioassay method for its quality control.
Shan-Shan LI ; Hai-Zhu ZHANG ; Long ZHANG ; Shuai-Shuai CHEN ; Xian HE ; Xiao-He XIAO ; Jia-Bo WANG ; Ming NIU
China Journal of Chinese Materia Medica 2021;46(10):2556-2564
Based on the heat-clearing and detoxifying effects of Gentianae Radix et Rhizoma, the network pharmacology is mainly used to predict the potential targets of Gentianae Radix et Rhizoma for anti-inflammatory activity and to perform the experimental verification. A method for detecting the biological potency of Gentianae Radix et Rhizoma based on verifiable targets has been established to provide a reference for improving the quality evaluation and control standards of Gentianae Radix et Rhizoma. High performance liquid chromatography can be used to construct chemical fingerprints of different batches of Gentianae Radix et Rhizoma. Constructing a component-target-disease network of Gentianae Radix et Rhizoma for its anti-inflammatory activity was applied to screen potential anti-inflammatory components and related targets of Gentianae Radix et Rhizoma, and to verify the target of Gentianae Radix et Rhizoma by using biological evaluation methods. Detecting the biological potency of different batches of Gentianae Radix et Rhizoma extracts was used to inhibit COX-2 enzyme activity based the verifiable target cyclooxygenase-2(COX-2). The results showed that different batches of Gentianae Radix et Rhizoma accorded with the pharmacopoeia testing regulations, and the chemical fingerprints have a high similarity(similarity>0.93), suggesting that there is no significant difference in the characteristics of the chemical components. Based on network pharmacology predictions, 18 candidate targets were found to have potential direct interactions with the ingredients in Gentianae Radix et Rhizoma. Among them, the most important target is COX-2. Based on the experimental verification of recombinant human COX-2 protease activity inhibition, Gentianae Radix et Rhizoma can inhibit the COX-2 enzyme activity in a dose-dependent manner. It can function with a low concentration(0.75 mg·mL~(-1)), which preliminarily confirmed the accuracy of network pharmacology prediction. The biological potency detection method of Gentianae Radix et Rhizoma based on COX-2 inhibitory activity was optimized and established. The qualitative response parallel line method was used to calculate the biological potency of anti-inflammatory activity, which ranged from 23.04 to 46.60 U·mg~(-1). For network pharmacology prediction, it can screen and clarify the possible targets of traditional Chinese medicine rapidly, which can guide the establishment of a biological evaluation method for the quality of medicinal materials with related activities. Compared with chemical fingerprints, the biological potency testing can better detect quality fluctuations of traditional Chinese medicine.
Anti-Inflammatory Agents/pharmacology*
;
Biological Assay
;
Drugs, Chinese Herbal/pharmacology*
;
Humans
;
Medicine, Chinese Traditional
;
Quality Control
;
Rhizome
8.Evaluation on the effectiveness of combination of biocontrol agents in managing Ganoderma boninense of oil palm
Feodora Grace Japanis ; Yow San Chan ; Khim Phin Chong
Malaysian Journal of Microbiology 2021;17(1):1-10
Aims:
The development of an effective biocontrol formulation for inhibition of Ganoderma boninense, a well-known
destructive pathogen in oil palm plantation is important to prolong the palm’s lifespan and reduce the losses due to this
disease. In this paper, we present some new bioformulations with combination of different types of biocontrol agents in
managing basal stem rot (BSR) disease.
Methodology:
The effectiveness of the treatments designed as T1 (Trichoderma harzianum + Lecanicillium spp. +
Streptomyces sundarbansensis + Pseudomonas aeruginosa), T2 (Penicillium simplicissimum + Lecanicillium sp. + S.
sundarbansensis + P. aeruginosa), T3 (P. simplicissimum + P. aeruginosa) and T4 (LEStani®) was evaluated through
treatment on the oil palm seedlings artificial infected by G. boninense and the results were expressed in disease severity
index (DSI), bole severity index (BSI) and ergosterol content.
Conclusion, significance and impact of study
All tested treatments (T1-T4) managed to control the severity of the
Ganoderma infection from continuously increasing when the treatments were applied either one month before or after
artificial inoculation. The disease severity of infected seedlings without treatments had increased for almost 2-fold at the
end of the trial. Moreover, T1 had the greatest inhibition of G. boninense with the lowest ergosterol content (a
bioindicator of Ganoderma colonization) detected (676.67 g/mL), which is about 1.9-fold lower than control (1273.33
ug/mL) without treatments and a BSI score of 1. Based on the effectiveness among the four tested biocontrol
formulations, T1 is the most promising formulation to be further evaluated in the field for control of BSR disease.
However, more research is needed in the future to estimate the effective amount for application in open environment.
Palm Oil
;
Biological Control Agents
;
Ganoderma
9.Effects of nutrient additives and incubation period on sporulation and viability of the entomopathogenic fungus, Metarhizium anisopliae (Hypocreales: Clavicipitaceae)
Najihah Abdul Halim ; Johari Jalinas ; Azlina Zakaria ; Samsudin Amit ; Zazali Chik ; Idris Abdul Ghani ; Wahizatul Afzan Azmi
Malaysian Journal of Microbiology 2021;17(1):97-102
Aims:
Metarhizium anisopliae is an entomopathogenic fungus (EPF) that exists naturally in the environment and
potentially be used as a biological control agent against many insect pests. This study aims to evaluate the effect of
nutrient additives on the yield and viability of M. anisopliae spore and to determine the optimum incubation period for
maximum spore production.
Methodology and results:
In this study, M. anisopliae was cultivated by solid-state fermentation using rice as a growth
medium. Three different nutrient additives were examined which aimed to maximize the production of M. anisopliae
spores. Among the three nutrient additives evaluated, yeast (1.84 ± 0.04 g) supported better growth and spore
production than molasses (0.58 ± 0.04 g) and palm oil (0.47 ± 0.09 g). The incubation period between 2-6 weeks
produced higher spore yield (0.97 ± 0.02 g spores) at week 4 with a better spore viability (86.30 ± 0.45%) at week 2.
Conclusion, significance and impact of study
Hence, it is suggested that the optimum incubation period is between
2 and 6 weeks after inoculation, and M. anisopliae could be mass produced in large quantities on rice substrate with the
addition of yeast as the nutrient additives.
Biological Control Agents
;
Microbial Viability
;
Metarhizium
10.Screening, identification and antagonistic effect evaluation of biocontrol strains to Asarum leaf blight.
Ya-Ling LIU ; Ying YU ; Li-Li CUI ; Hui-Xia LEI ; Hai-Kun LU ; Jing GUO
China Journal of Chinese Materia Medica 2020;45(5):1047-1052
Leaf blight is the main disease of Asarum. At present, chemical treatment is main measure for disease control, and there is no report on biological control. In order to achieve the biological control of Asarum leaf blight, the biocontrol strains with antagonistic effect on Asarum leaf blight were screened. The rhizosphere bacteria of healthy Asarum plants were isolated by soil dilution method, and the isolated strains were screened by the methods of antagonistic antifungal and fermentation liquid antifungal, then the strains were identified and the control effect in vivo was determined. Abiocontrol bacterial strains S2-31 which with high antagonism to leaf blight was obtained from more than 100 isolated strains. The inhibitory rates of antagonistic antifungal and fermentation liquid antifungal reached 92.47% and 60.56%, respectively. It was identified by morphology and 16 S rDNA sequence analysis, and the strain was identified as Brevibacillus laterosporus. The results of indoor potted experiment showed that the control effect was 79.87%, 71.44% and 66.82% on the 3 rd, 5 th and 7 th day after inoculation, respectively, which indicated that S2-31 could reduce the disease index and control the development of Asarum leaf blight.
Antibiosis
;
Asarum/microbiology*
;
Biological Control Agents
;
DNA, Ribosomal
;
Firmicutes
;
Fungi/pathogenicity*
;
Plant Diseases/prevention & control*
;
Rhizosphere
;
Soil Microbiology


Result Analysis
Print
Save
E-mail