1.The use of phosphorus nanoparticles synthesized by rhizospheric fungus Aspergillius fumigatus as a nanofertilizer for flax plant
Rabaa Yaseen ; Basma Hamdy Amin
Malaysian Journal of Microbiology 2021;17(3):244-253
Aims:
This study examined the mycosynthesis of phosphorus nanoparticles (PNPs) and its application as a fertilizer for flax plant.
Methodology and results:
A total of thirty eight fungal isolates were isolated and screened for their abilities to
synthesize PNPs. The fungal isolate was determined and identified as Aspergillus fumigatus (NCBI GenBank accession
No. MN610566-MN610567). The biosynthesized nanoparticles were characterized by particle size analyzer, UV-visible
spectrophotometer, transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDX) and fourier
transform infrared spectroscopy (FT-IR). They were found to have an average diameter of 45.1 nm, regular round
shape, EDX confirms the 54.63 atom % of phosphorous. The cytotoxicity of produced nanoparticles was performed to
determine the safe dose that will be applied in agricultural experiment and was found to be 12.5 μg/mL. Pot experiment
was performed to determine the fertilizing impact of mycosynthesized PNPs on flax plant and to equate their influence
with granular single super phosphate. Results revealed that growth parameters, phosphorus content and microbial
activities in the rhizosphere of flax plants were highly significantly (p ≤ 0.05) affected by foliar application of PNPs in
presence of half dose of super phosphate. The TEM-micrographs of stained ultrastructural leaves showed that the PNPs
treated leaves in the presence of half dose of super phosphate had normal cell structure similar to control, while the cell
structure of leaves treated with PNPs but did not receive super phosphate were adversely affected.
Conclusion, significance and impact of study
This study clearly indicated that the application of low cost
biosynthesised PNPs could save about 50% of recommended dose of phosphorus fertilizer. This study also
demonstrates that it is not preferred to use PNPs as a fertilizer alone without adding super phosphate. Hence, this
investigation suggests that further studies should be established to detect the safety of this nanofertilizers.
Nanoparticles--chemistry
;
Aspergillus fumigatus
2.Expression of β-glucosidase An-bgl3 from Aspergillus niger for conversion of scopolin.
Kunpeng YU ; Cheng PENG ; Yanling LIN ; Lijun LI ; Hui NI ; Qingbiao LI
Chinese Journal of Biotechnology 2023;39(3):1232-1246
Scopoletin is a coumarin compound with various biological activities including detumescence and analgesic, insecticidal, antibacterial and acaricidal effects. However, interference with scopolin and other components often leads to difficulties in purification of scopoletin with low extraction rates from plant resource. In this paper, heterologous expression of the gene encoding β-glucosidase An-bgl3 derived from Aspergillus niger were carried out. The expression product was purified and characterized with further structure-activity relationship between it and β-glucosidase analyzed. Subsequently, its ability for transforming scopolin from plant extract was studied. The results showed that the specific activity of the purified β-glucosidase An-bgl3 was 15.22 IU/mg, the apparent molecular weight was about 120 kDa. The optimum reaction temperature and pH were 55 ℃ and 4.0, respectively. Moreover, 10 mmol/L metal ions Fe2+ and Mn2+ increased the enzyme activity by 1.74-fold and 1.20-fold, respectively. A 10 mmol/L solution containing Tween-20, Tween-80 and Triton X-100 all inhibited the enzyme activity by 30%. The enzyme showed affinity towards scopolin and tolerated 10% methanol and 10% ethanol solution, respectively. The enzyme specifically hydrolyzed scopolin into scopoletin from the extract of Erycibe obtusifolia Benth with a 47.8% increase of scopoletin. This demonstrated that the β-glucosidase An-bgl3 from A. niger shows specificity on scopolin with good activities, thus providing an alternative method for increasing the extraction efficiency of scopoletin from plant material.
Aspergillus niger/genetics*
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beta-Glucosidase/chemistry*
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Scopoletin
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Polysorbates
;
Coumarins
3.Extraction and characterization of antifungal substances produced by antagonistic Streptomyces S24.
Qisheng ZHOU ; Ningning CAO ; Nianquan QIU ; Benfeng ZHANG ; Nan ZHANG ; Xunli LIU
Chinese Journal of Biotechnology 2010;26(3):350-356
Streptomyces S24 has broad spectrum resistance to the Aspergillus in food and feed, such as Aspergillus flavus, Aspergillus niger, Asperegillus alutacells and so on. We studied the adsorption and desorption properties of antifungal substance from Streptomyces S24 on macroporous resins, screened the best elution solution and also investigated some physical and chemical characters of antifungal substance by determining the antifugal activity using oxford plate assay system. According to the analysis results, AB-8 resin offered the best adsorption and desorption capacity for antifungal substance and its saturated absorption capacity was 7.0822 x 10(4) microg/g, the optimal elution solution was 85% acetone and the dynamic desorption rate could reach 93.82%. The antifungal substance was stable to heat and alkali, not sensitive to organic solvents, and sensitive to ultraviolet rays and acid. Based on its ultraviolet spectrometry, the antifungal substance was identified as heptaene macrolide antibiotic.
Adsorption
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Antifungal Agents
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chemistry
;
isolation & purification
;
pharmacology
;
Aspergillus
;
drug effects
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Aspergillus flavus
;
drug effects
;
Aspergillus niger
;
drug effects
;
Streptomyces
;
chemistry
;
metabolism
4.Investigation of aflatoxins,mycobiota,and toxigenic fungi during post-harvest handling of Ziziphi Spinosae Semen.
Xi-Mei ZHANG ; Wei-Wei GAO ; Yan-Hong HAO ; Xiao-Lin JIAO ; Bao-Lin GUO ; Ya-Lin XUE ; Jian-Ting BAI ; Zhen-Hong LEI
China Journal of Chinese Materia Medica 2019;44(10):2009-2014
Ziziphi Spinosae Semen is one of the Chinese herbal medicine being susceptible to aflatoxins contamination. To investigate the sources of aflatoxins contamination and toxigenic fungi species on Ziziphi Spinosae Semen,32 samples were collected from multiple steps during the post-harvest processing in this study. Aflatoxins in these samples were determined by immunoaffinity column and HPLC coupled with post-column photochemical derivatization. The dilution-plate method was applied to the fungi isolation. The isolated fungi strains were identified by morphological characterization and molecular approaches. The results showed that aflatoxins were detected in 28 samples from every step during the processing of Ziziphi Spinosae Semen. Three samples were detected with aflatoxin B_1 and 2 samples with both aflatoxin B_1 and total aflatoxin exceeding the limit of Chinese Pharmacopoeia. Especially the samples from the washing step,with the highest detected amounts of AFB_1 and AFs were reached 94. 79,121. 43 μg·kg~(-1),respectively. All 32 samples were contaminated by fungi. The fungal counts on the newly harvested samples were 2. 20 × 10~2 CFU·g~(-1). Moreover,it increased as tphreocessing progresses,and achieved 1. 16×10~6 CFU·g~(-1) after washing. A total of 321 isolates were identified to 17 genera. Aspergillus flavus was the main source of aflatoxins during the processing and storage of Ziziphi Spinosae Semen. One isolate of A. flavus was confirmed producing AFB_1 and AFB_2. The fungal count was significantly increased by composting,and Aspergillus was the predominant genus after shell breaking. The contamination level of aflatoxins was increased by composting and washing.
Aflatoxins
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analysis
;
Aspergillus
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Chromatography, High Pressure Liquid
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Fungi
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isolation & purification
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Seeds
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chemistry
;
microbiology
;
Ziziphus
;
chemistry
5.Seven drimane-type sesquiterpenoids from an earwig-associated Aspergillus sp.
Khan SALMAN ; Hongjie ZHU ; Ziqian SUN ; Yilin LI ; Lan WANG ; Rong WANG ; Zhikai GUO ; Ruihua JIAO
Chinese Journal of Natural Medicines (English Ed.) 2023;21(1):58-64
Drimane-type sesquiterpenoids are widely distributed in fungi. From the ethyl acetate extract of the earwig-derived Aspergillus sp. NF2396, seven new drimane-type sesquiterpenoids, named drimanenoids A-G (1-7), were isolated. Their structures were elucidated by diverse spectroscopic analysis including high-resolution ESI-MS, one- and two-dimensional NMR spectroscopy. Drimanenoids A-F (1-6) are new members of drimane-type sesquiterpenoid esterified with unsaturated fatty acid side chain at C-6. Drimanenoids C (3), D (4) and F (6) showed antibacterial activity against five types of bacteria with different inhibition diameters. Drimanenoid D (4) exhibited moderate cytotoxicity against human myelogenous leukemia cell line K562 with an IC50 value of 12.88 ± 0.11 μmol·L-1.
Humans
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Polycyclic Sesquiterpenes
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Sesquiterpenes/chemistry*
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Aspergillus/chemistry*
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Magnetic Resonance Spectroscopy
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Molecular Structure
6.A new phenolic compound from endophytic fungus Aspergillus fumigatus of Euphorbia royleana.
Yan-Jun CHEN ; Yan-Qi SUN ; Rui-Qi ZHANG ; Li-Jun ZHU ; Yi-Jian CHEN ; Li-Juan YANG ; Min ZHOU ; Miao DONG ; Yan-Qing YE
China Journal of Chinese Materia Medica 2019;44(24):5429-5432
This research was carried out to study the secondary metabolites of endophytic fungus Aspergillosis fumigatus from Euphorbia royleana. The endophytic fungus A. fumigatus was fermented by solid fermentation,and purified by various chromatographic methods after extraction. The structures of the compounds were identified by1 H-NMR,13 C-NMR and HSQC,HMBC spectra and physicchemical properties. Three compounds were isolated and their structures were identified as 3-( 3,4-dihydroxybenzoyl)-5-( 3,4-dihydroxyphenyl)-6-methyl-5,6-dihydro-2 H-pyran-2-one( 1),hydroxysydonic acid( 2) and 11-hydroxysydonic acid( 3). Compound 1 is a new compound.
Aspergillus fumigatus/chemistry*
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Endophytes/chemistry*
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Euphorbia/microbiology*
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Fermentation
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Phenols/isolation & purification*
7.One-step fermentation for producing simvastatin via RNAi silencing of lovF gene in Aspergillus terreus.
Na LI ; Meihong LI ; Zhen YU ; Jun ZHOU ; Jun HUANG
Chinese Journal of Biotechnology 2016;32(4):478-486
Simvastatin is one of the important prescription drugs for hypercholesterolemia. Monacolin J is a key intermediate during simvastatin synthesis, and also an intermediate of lovastatin biosynthesis. In this work, we construct a monacolin J producing strain via RNA interference to achieve one-step fermentation to obtain simvastatin. The lovF gene silencing plasmid pMHJ137 was constructed and transformed into Aspergillus terreus by Agrobacterium tumefaciens mediated transformation method. Precursor DMB-S-MMP was supplied during the fermentation to screen positive strains of transformants; which also further confirmed the simvastatin producing capability of MJ1-24 by one-step fermentation. Strain MJ1-24 produced monacolin J rather than lovastatin, and the feeding of DMB-S-MMP resulted in the generation of simvastatin. This study suggested that RNAi can efficiently silence the lovF gene of A. terreus and promote the simvastatin production by one-step fermentation.
3-Mercaptopropionic Acid
;
analogs & derivatives
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Aspergillus
;
chemistry
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genetics
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Fermentation
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Industrial Microbiology
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Naphthalenes
;
chemistry
;
RNA Interference
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Simvastatin
;
chemistry
8.Aflatoxins and fungal community distribution during harvesting and processing of Platycladi Semen.
Zhen-Ying LIU ; Hao-Nan WANG ; Zhao-Yu ZHANG ; Jing XUAN ; Min LI ; Zhe LI ; Yong-Qing ZHANG
China Journal of Chinese Materia Medica 2022;47(2):385-391
This study aimed to analyze aflatoxins content and fungal community distribution in the harvesting and processing of Platycladi Semen, and explore the key link that affects aflatoxins contamination. The related Platycladi Semen samples of different maturity periods(cone non-rupture period, early rupture, and complete rupture period) and different processing periods(before drying, during 2-d drying, during 7-d drying, before and after seed scale removal, before and after peeling, 1 d after color sorting, and 7 d after color sorting) were collected for identifying the fungal community composition on sample surface by ITS amplicon sequencing. Then the content of aflatoxins B_1, B_2, G_1 and G_2 was determined by HPLC-MS/MS. The results showed that during the harvesting of Platycladi Semen from cone non-rupture to complete rupture, aflatoxins were only detected in the seed scale and seed coat, with aflatoxin G_2 in the seed scale and aflatoxin B_1 in the seed coat. During the drying, with the prolongation of drying time, aflatoxins B_1 and G_2 were detected simultaneously in the seed scale, aflatoxin B_1 in the seed coat, and low-content aflatoxin B_1 in the seed kernel. During subsequent processing, the aflatoxin content in seed kernel during subsequent processing was slighted increased. As demonstrated by fungal detection, Aspergillus flavus was not present during the harvesting of Platycladi Semen, but present during the drying and processing. Its content in the seed coat during the drying process was relatively higher. In short, Platycladi Semen should be harvested as soon as possible after it becomes fully mature. Drying process is the key link of preventing aflatoxin contamination. It is advised to build a sunlight room or adopt similar settings, standardize the operations in other processes, and keep the surrounding environment clean to minimize aflatoxin contamination.
Aflatoxins/analysis*
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Aspergillus flavus
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Food Contamination/prevention & control*
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Mycobiome
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Semen/chemistry*
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Tandem Mass Spectrometry
9.A new polyketide of endophytic fungi Aspergillus sp. ZJ-58 from Coptis chinensis.
Guo-Ping YIN ; Chun WEN ; Ya-Juan LI ; Du SHI ; Jing-Jing ZHU ; Chang-Hua HU
China Journal of Chinese Materia Medica 2022;47(4):967-971
A new polyketide, coptaspin A(1), along with two known compounds 4-acetyl-3,4-dihydro-6,8-dihydroxy-3-methoxy-5-methylisocoumarin(2), and cytochalasin Z_(12)(3), was isolated from the endophytic fungi Aspergillus sp. ZJ-58, which was isolated from the genuine medicinal plant Coptis chinensis in Chongqing after solid-state fermentation on rice and silica gel, MCI, and HPLC-based separation. Their structures were elucidated by MS, NMR, IR, UV, and ECD. The newly isolated compound 1 showed moderate inhibitory activities against LPS-induced NO production in RAW264.7 macrophages with the IC_(50) value of 58.7 μmol·L~(-1), suggesting its potential anti-inflammatory activity.
Anti-Inflammatory Agents/pharmacology*
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Aspergillus/chemistry*
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Coptis chinensis
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Plants, Medicinal
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Polyketides/pharmacology*
10.An epipolythiodioxopiperazine alkaloid and diversified aromatic polyketides with cytotoxicity from the Beibu Gulf coral-derived fungus Emericella nidulans GXIMD 02509.
Miaoping LIN ; Zhenzhou TANG ; Jiaxi WANG ; Humu LU ; Chenwei WANG ; Yanting ZHANG ; Xinming LIU ; Chenghai GAO ; Yonghong LIU ; Xiaowei LUO
Journal of Zhejiang University. Science. B 2023;24(3):275-280
Marine microorganisms, especially marine fungi, have historically proven their value as a prolific source for structurally novel and pharmacologically active secondary metabolites (Deshmukh et al., 2018; Carroll et al., 2022). The corals constitute a dominant part of reefs with the highest biodiversity, and harbor highly diverse and abundant microbial symbionts in their tissue, skeleton, and mucus layer, with species-specific core members that are spatially partitioned across coral microhabitats (Wang WQ et al., 2022). The coral-associated fungi were very recently found to be vital producers of structurally diverse compounds, terpenes, alkaloids, peptides, aromatics, lactones, and steroids. They demonstrate a wide range of bioactivity such as anticancer, antimicrobial, and antifouling activity (Chen et al., 2022). The genetically powerful genus Emericella (Ascomycota), which has marine and terrestrial sources, includes over 30 species and is distributed worldwide. It is considered a rich source of diverse secondary metabolites with antimicrobial activity or cytotoxicity (Alburae et al., 2020). Notably, Emericella nidulans, the sexual state of a classic biosynthetic strain Aspergillus nidulans, was recently reported as an important source of highly methylated polyketides (Li et al., 2019) and isoindolone-containing meroterpenoids (Zhou et al., 2016) with unusual skeletons.
Animals
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Aspergillus nidulans
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Polyketides/chemistry*
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Anthozoa/microbiology*
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Anti-Infective Agents/pharmacology*
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Alkaloids