Unraveling the Metabolite Signature of Endophytic Bacillus velezensis Strain Showing Defense Response Towards Fusarium oxysporum

Seedling blight, caused by the fungus Fusarium oxysporum, significantly lowers rice production globally. Earlier reports have opined that endophytic bacteria strains could be possible biocontrol agents, but the mechanistic actions involved are still unclear. Therefore, this study aimed to isolate the endophytic bacteria with high inhibitory activity and elucidate its possible mechanisms for inducing resistance by metabolomics. The results showed that mdj-36 had the strongest in vitro pathogen inhibition of F. oxysporum, while mdj-34 displayed the lowest inhibitory activity identified as Bacillus velezensis strains. Metabolomic analyses demonstrated that B. velezensis mdj-36 growth medium could produce higher organic acids, terpenes, and diterpene than B. velezensis mdj-34. Further investigation revealed that ‘secondary bile acid biosynthesis’ and ‘glycerophospholipid metabolism’ pathways played essential roles in defense response towards F. oxysporum. This study’s findings provide a credible theoretical basis for the possible use of the B. velezensis strain against rice seedling blight.

Download Full-text

Self-Inhibitory Activity of Trichoderma Soluble Metabolites and Their Antifungal Effects on Fusarium oxysporum

Journal of Fungi ◽

10.3390/jof6030176 ◽

2020 ◽

Vol 6 (3) ◽

pp. 176

Author(s):

Samuel Álvarez-García ◽

Sara Mayo-Prieto ◽

Santiago Gutiérrez ◽

Pedro Antonio Casquero

Keyword(s):

Fusarium Oxysporum ◽

Inhibitory Activity ◽

Inhibitory Effects ◽

Trichoderma Spp ◽

Macroscopic Structure ◽

Biocontrol Activity ◽

Microbial Strains ◽

Phytopathogenic Microorganisms

Self-inhibitory processes are a common feature shared by different organisms. One of the main mechanisms involved in these interactions regarding microorganisms is the release of toxic diffusible substances into the environment. These metabolites can exert both antimicrobial effects against other organisms as well as self-inhibitory ones. The in vitro evaluation of these effects against other organisms has been widely used to identify potential biocontrol agents against phytopathogenic microorganisms. In the present study, we performed membrane assays to compare the self-inhibitory effects of soluble metabolites produced by several Trichoderma isolates and their antifungal activity against a phytopathogenic strain of Fusarium oxysporum. The results demonstrated that Trichoderma spp. present a high self-inhibitory activity in vitro, being affected in both their growth rate and the macroscopic structure of their colonies. These effects were highly similar to those exerted against F. oxysporum in the same conditions, showing no significant differences in most cases. Consequently, membrane assays may not be very informative by themselves to assess putative biocontrol capabilities. Therefore, different methods, or a combination of antifungal and self-inhibitory experiments, could be a better approach to evaluate the potential biocontrol activity of microbial strains in order to pre-select them for further in vivo trials.

Download Full-text

KEMAMPUAN EKSTRAK SENYAWA AKTIF BAKTERI ENDOFIT DALAM MENGHAMBAT PERTUMBUHAN Fusarium oxysporum f.sp. PADA KELAPA SAWIT

Jurnal Bioteknologi & Biosains Indonesia (JBBI) ◽

10.29122/jbbi.v5i2.2769 ◽

2018 ◽

Vol 5 (2) ◽

pp. 214

Author(s):

Emilia Candrawati ◽

Bedah Rupaedah ◽

Sumpono Sumpono ◽

Agus Sundaryono

Keyword(s):

Fusarium Oxysporum ◽

Oil Palm ◽

Active Compound ◽

Endophytic Bacteria ◽

Culture Method ◽

Bioactive Compound ◽

Bacterial Isolates ◽

Active Compounds ◽

Activity Test

Ability of Active Compound Extract of Endophytic Bacteria to Inhibit the Growth of Fusarium oxysporum f.sp. in Oil Palm ABSTRACTWilt vessels disease in oil palm plants is caused by Fusarium oxysporum f.sp. This disease is very harmful because of its ability to kill the infected oil palm plant in less than a year. Endophytic bacteria are likely to be biological controllers for the disease because of their ability to produce bioactive antifungal compounds. Isolation of endophytic bacteria from oil palm plant and activity test of their active compounds against F. oxysporum f.sp. in vitro had been done. Antagonistic test of endophytic bacterial isolates against F. oxysporum f.sp. was carried out using a double culture method. The potential endophytic bacterial isolates were extracted using ethyl acetate solvent for their active compounds, which were then tested for its activity in inhibiting the growth of F. oxysporum f.sp. The results showed that the active compound extract of B11 endophytic bacteria with the incubation time of 24 and 54 hours gave the growth inhibition of F. oxysporum f.sp. at the level of 29.23% and 43.85%, respectively.Keywords: antagonistic test, bioactive compound, endophytic bacteria, F. oxysporum f.sp., oil palm ABSTRAKPenyakit layu pembuluh pada tanaman kelapa sawit disebabkan oleh Fusarium oxysporum f.sp. Penyakit ini menjadi penyebab kematian tanaman kelapa sawit yang telah terinfeksi dalam waktu kurang dari setahun. Bakteri endofit asal tanaman kelapa sawit dimungkinkan menjadi pengendali hayati bagi penyakit ini karena kemampuan bakteri tersebut memproduksi senyawa bioaktif yang bersifat antifungi. Isolasi bakteri endofit dari tanaman kelapa sawit dan uji aktivitas senyawa aktifnya terhadap F. oxysporum f.sp. secara in vitro telah dilakukan. Uji antagonis isolat bakteri endofit terhadap jamur patogen F. oxysporum f.sp. menggunakan metode kultur ganda. Isolat bakteri endofit potensial diekstrak senyawa aktifnya dengan menggunakan pelarut etil asetat, kemudian senyawa aktif ini diuji aktivitasnya dalam menghambat pertumbuhan jamur patogen F. oxysporum f.sp. Hasil penelitian menunjukkan bahwa ekstrak senyawa aktif bakteri endofit B11 dengan waktu inkubasi 24 dan 54 jam memberikan daya hambat terhadap F. oxysporum f.sp. sebesar masing-masing 29,23% dan 43,85%.Kata Kunci: bakteri endofit, F. oxysporum f.sp., kelapa sawit, senyawa aktif, uji antagonis

Download Full-text

Tomato Endophytic Bacteria Composition and Mechanism of Suppressiveness of Wilt Disease (Fusarium oxysporum)

Frontiers in Microbiology ◽

10.3389/fmicb.2021.731764 ◽

2021 ◽

Vol 12 ◽

Author(s):

Zeyu Zhang ◽

Ji Li ◽

Zengqiang Zhang ◽

Youzhou Liu ◽

Yuquan Wei

Keyword(s):

Fusarium Oxysporum ◽

Endophytic Bacteria ◽

High Throughput Sequencing ◽

High Efficiency ◽

Abiotic Factors ◽

Wilt Disease ◽

Agricultural Practice ◽

Pathogen Invasion ◽

Disease Diagnostics

Tomato wilt disease, caused by the Fusarium oxysporum is an ever-increasing threat for agricultural production, and unreasonable fertilization and pesticide abuse caused environmental challenge. Increasing evidence suggested that microbiomes or those associated with crops, played key roles on plant health. Plant disease dynamics were affected by multiple biotic and abiotic factors including phytopathogen population density, the genetic type of the pathogen and the host, in particular, the composition and assembly of the host-associated microbiome. However, it was unclear how pathogen invasion interaction and correlate with endophytic bacterial communities in natural field conditions. To study this, we sampled temporally the tomato plants that were exposed to F. oxysporum invasions over one crop season. High-throughput sequencing were performed to explore the correlation between agricultural practice, pathogen invasion, and endophytic microbiota communities. Results showed that pathogen invasion had clear effect on the endophytic and a strong link between increased pathogen densities and reduced abundance of Bacillus sp., which are crucial taxonomy for suppressiveness to F. oxysporum in vitro and in greenhouse condition. In summary, monitoring the dynamics of endophytic bacteria communities and densities of pathogen could thus open new avenue for more accurate disease diagnostics and high-efficiency screening antagonisms methods in the future, and our results will broaden the agricultural view of beneficial microbiota as biological control agents against plant pathogen.

Download Full-text

Assessment of antimicrobial activity in vitro of ethanolic extracts of Banisteriopsis anisandra (A. Juss.) B. Gates (Malpighiaceae)

Revista Brasileira de Plantas Medicinais ◽

10.1590/s1516-05722013000300017 ◽

2013 ◽

Vol 15 (3) ◽

pp. 431-437 ◽

Cited By ~ 6

Author(s):

M.S. Pádua ◽

M.C. Mendes-Costa ◽

J.M.S. Ferreira ◽

J.C. Magalhães ◽

A.H.F. Castro

Keyword(s):

Antimicrobial Activity ◽

Fusarium Oxysporum ◽

Inhibitory Activity ◽

Ethanolic Extract ◽

Phytopathogenic Fungi ◽

Significant Inhibition ◽

Plant Diseases ◽

Growth Speed ◽

Ethanolic Extracts

The aim of this study was to evaluate the antimicrobial activity in vitro of ethanolic extracts of Banisteriopsis anisandra. Tests were performed using the extracts overlay method in the culture medium for phytopathogenic fungi Rhizoctonia solani and Fusarium oxysporum, and disk diffusion for the microorganisms Staphylococcus aureus and Candida albicans. Ethanolic extracts from leaves were prepared by maceration (extract I) and decoction (extract II) at 430.0, 215.0 and 107.5 mg/mL. The growth inhibition of R. solani and F. oxysporum was determined by calculating the mycelia growth speed rate (MGSR) and, in relation C. albicans and S. aureus, it was determined by measuring the inhibition halos. Extracts that caused significant inhibition were also tested at 86.0, 64.5, 43.0 and 21.5 mg/mL for C. albicans and S. aureus. Both extracts showed inhibitory activity on the microorganisms studied. Rizoctonia solani showed lower MGSR in the presence of extract II (107.5 mg/mL) and Fusarium oxysporum showed slight MGSR reduction in the presence of extract I (107.5 mg/mL) and II (107.5 and 215 mg/mL). Ethanolic extracts I and II inhibited the growth of C. albicans, with the highest rates of inhibition observed in the presence of extract II (215.0 mg/mL). For S. aureus, the highest inhibitory activity was observed in the presence of ethanolic extract II, prepared by decoction at 430.0 mg/mL. Results showed a promising antimicrobial activity of extracts of B. anisandra, which may contribute to further studies leading to a future development of medicines to treat human and plant diseases caused by these organisms.

Download Full-text

Preventive Effects of Fluoro-Substituted Benzothiadiazole Derivatives and Chitosan Oligosaccharide against the Rice Seedling Blight Induced by Fusarium oxysporum

Plants ◽

10.3390/plants8120538 ◽

2019 ◽

Vol 8 (12) ◽

pp. 538 ◽

Cited By ~ 6

Author(s):

Bo Ma ◽

Junhe Wang ◽

Chuanzeng Liu ◽

Jifang Hu ◽

Kefei Tan ◽

...

Keyword(s):

Fusarium Oxysporum ◽

Molecular Mechanisms ◽

Disease Incidence ◽

Rice Seedling ◽

Root Growth Inhibition ◽

Chitosan Oligosaccharide ◽

Seedling Blight ◽

Lack Of Information ◽

Biochemical Analyses ◽

Root Tissues

Rice seedling blight, caused by Fusarium oxysporum, significantly affects global rice production levels. Fluoro-substituted benzothiadiazole derivatives (FBT) and chitosan oligosaccharide (COS) are elicitors that can enhance plant resistance to pathogen infection. However, there is a lack of information regarding FBT and COS used as elicitors in rice seedlings blight. Therefore, the aim of this study was to evaluate the effect of FBT and COS treatments on rice seedling blight and elucidate the molecular mechanisms of the two elicitors for inducing resistance using proteomic technique. Results indicated that FBT and COS significantly reduced the disease incidence and index, and relived the root growth inhibition caused by F. oxysporum (p < 0.05). Biochemical analyses demonstrated that these two elicitors effectively enhanced activities of defense enzymes. Moreover, the proteomic results of rice root tissues disclosed more differentially expressed proteins in diterpenoid biosynthesis pathway that were particularly stimulated by two elicitors compared to the other pathways studied, resulting in the accumulation of antimicrobial substance, momilactone. Findings of this study could provide sound theoretical basis for further applications of FBT and COS used as rice elicitors against seedling blight.

Download Full-text

A Potential Application of Endophytic Bacteria in Strawberry Production

Horticulturae ◽

10.3390/horticulturae7110504 ◽

2021 ◽

Vol 7 (11) ◽

pp. 504

Author(s):

Chuansheng Mei ◽

B. Sajeewa Amaradasa ◽

Robert L. Chretien ◽

Danyang Liu ◽

George Snead ◽

...

Keyword(s):

Endophytic Bacteria ◽

Fungal Pathogens ◽

Abiotic Stress Tolerance ◽

Field Trials ◽

Fruit Yield ◽

Bacillus Velezensis ◽

Yield Production ◽

Promote Plant Growth ◽

Marketable Fruit

Endophytic bacteria could be used as a tool to promote plant growth, enhance abiotic stress tolerance, and inhibit plant pathogen growth. More than 100 bacteria, previously tested to have biocontrol activity against fungal pathogens from our lab, were chosen for pathogen inhibition in vitro with antibiosis assays against strawberry specific pathogens. Three potential endophytic bacteria were tested in the greenhouse for disease reduction and growth performance. Finally, field trials were conducted for fruit yield production. Our results showed that three endophytic bacteria significantly inhibited the growth of the strawberry pathogen Colletotrichum gloeosporioides from antibiosis assays and were identified as Bacillus velezensis strains IALR308, IALR585, and IALR619. Inoculation of these bacteria significantly reduced strawberry disease in greenhouse conditions with pathogen infection. Field trials showed that IALR619 has potential to influence marketable fruit yield when strawberry plants were inoculated twice over the growing season. All three bacteria had the ability to produce auxin and to solubilize phosphate. The antibiotics surfactin and iturin were also detected in IALR585 and IALR619. In conclusion, Bacillus velezensis IALR619 has potential inhibition of strawberry pathogen growth in the greenhouse and possible ability to increase marketable fruit yield in the field.

Download Full-text

Inhibitory effects of bioaccessible anthocyanins and procyanidins from apple, red grape, cinnamon on α-amylase, α-glucosidase and lipase

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000652 ◽

2020 ◽

pp. 1-9

Author(s):

Pınar Ercan ◽

Sedef Nehir El

Keyword(s):

Inhibitory Activity ◽

Digestive Enzymes ◽

Positive Control ◽

Anthocyanin Content ◽

Inhibitory Effects ◽

Total Anthocyanin ◽

Total Anthocyanin Content ◽

Before And After ◽

Red Grape

Abstract. The goals of this study were to determine and evaluate the bioaccessibility of total anthocyanin and procyanidin in apple (Amasya, Malus communis), red grape (Papazkarası, Vitis vinifera) and cinnamon (Cassia, Cinnamomum) using an in vitro static digestion system based on human gastrointestinal physiologically relevant conditions. Also, in vitro inhibitory effects of these foods on lipid (lipase) and carbohydrate digestive enzymes (α-amylase and α-glucosidase) were performed with before and after digested samples using acarbose and methylumbelliferyl oleate (4MUO) as the positive control. While the highest total anthocyanin content was found in red grape (164 ± 2.51 mg/100 g), the highest procyanidin content was found in cinnamon (6432 ± 177.31 mg/100 g) (p < 0.05). The anthocyanin bioaccessibilities were found as 10.2 ± 1%, 8.23 ± 0.64%, and 8.73 ± 0.70% in apple, red grape, and cinnamon, respectively. The procyanidin bioaccessibilities of apple, red grape, and cinnamon were found as 17.57 ± 0.71%, 14.08 ± 0.74% and 18.75 ± 1.49%, respectively. The analyzed apple, red grape and cinnamon showed the inhibitory activity against α-glucosidase (IC50 544 ± 21.94, 445 ± 15.67, 1592 ± 17.58 μg/mL, respectively), α-amylase (IC50 38.4 ± 7.26, 56.1 ± 3.60, 3.54 ± 0.86 μg/mL, respectively), and lipase (IC50 52.7 ± 2.05, 581 ± 54.14, 49.6 ± 2.72 μg/mL), respectively. According to our results apple, red grape and cinnamon have potential to inhibit of lipase, α-amylase and α-glucosidase digestive enzymes.

Download Full-text