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Fulltext Lovastatin-enriched rice straw enhances biomass quality and suppresses ruminal methanogenesis

Faseleh Jahromi M, Liang JB, Mohamad R, Goh YM, Shokryazdan P, Ho YW

Biomed Res Int, 2013;2013:397934.
PMID: 23484116 DOI: 10.1155/2013/397934

The primary objective of this study was to test the hypothesis that solid state fermentation (SSF) of agro-biomass (using rice straw as model); besides, breaking down its lignocellulose content to improve its nutritive values also produces lovastatin which could be used to suppress methanogenesis in the rumen ecosystem. Fermented rice straw (FRS) containing lovastatin after fermentation with Aspergillus terreus was used as substrate for growth study of rumen microorganisms using in vitro gas production method. In the first experiment, the extract from the FRS (FRSE) which contained lovastatin was evaluated for its efficacy for reduction in methane (CH4) production, microbial population, and activity in the rumen fluid. FRSE reduced total gas and CH4 productions (P < 0.01). It also reduced (P < 0.01) total methanogens population and increased the cellulolytic bacteria including Ruminococcus albus, Fibrobacter succinogenes (P < 0.01), and Ruminococcus flavefaciens (P < 0.05). Similarly, FRS reduced total gas and CH4 productions, methanogens population, but increased in vitro dry mater digestibility compared to the non-fermented rice straw. Lovastatin in the FRSE and the FRS significantly increased the expression of HMG-CoA reductase gene that produces HMG-CoA reductase, a key enzyme for cell membrane production in methanogenic Archaea.

Matched MeSH terms: Aspergillus/metabolism*
Optimization of temperature, moisture content and inoculum size in solid state fermentation to enhance mannanase production by Aspergillus terreus SUK-1 using RSM

Rashid JI, Samat N, Mohtar W, Yusoff W

Pak J Biol Sci, 2011 May 01;14(9):533-9.
PMID: 22032082

Optimization of three parameters, temperature (25-35 degrees C), moisture content (40% (w/v)-60% (w/v) and inoculum sizes (5% (w/v)-15% (w/v) were investigated and optimized by Response Surface Methodology (RSM) for optimal mannanase production by Aspergillus terreus SUK-1. A second order polynomial equation was fitted and the optimum condition was established. The result showed that the moisture content was a critical factor in terms of its effect on mannanase. The optimum condition for mannanase production was predicted at 42.86% (w/v) initial moisture (31 C) temperature and 5.5% (w/v) inoculum size. The predicted optimal parameter were tested in the laboratory and the mannanase activity 45.12 IU mL-1 were recorded to be closed to the predicted value (44.80 IU mL-1). Under the optimized SSF condition (31 degrees C, 42.86% moisture content (w/v) and 5.5% inoculum size (w/v)), the maximum mannanase production was to prevail about 45.12 IU mL-1 compare to before optimized (30 degrees C, 50% moisture content (w/v) and 10% inoculum size (w/v)) was only 34.42 IU mL-1.

Matched MeSH terms: Aspergillus/metabolism*
Mixed herbs drugs: inhibitory effect on growth of the endogenous mycoflora and aflatoxin production

Razak MF, Aidoo KE, Candlish AG

Mycopathologia, 2009 May;167(5):273-86.
PMID: 18991016 DOI: 10.1007/s11046-008-9167-3

Twenty commercial mixed herbal drugs were examined for mycological profile. Aspergillus species were the predominant fungi found in the drugs. Other fungi harboured in the drugs with less frequency were Paecilomyces species, Eurotium species, Monascus species, Acremonium species, Penicillium species, Cladosporium species, Scopulariopsis species, Phialophora species and Fonseceae species. Fungal count was between 1.0 log(10) CFU and 2.4 log(10) CFU per gram of sample. When the drugs were incubated in 85% humidity at 25 degrees C, fungal colonies grew on only two of the drugs. The mixed herbal drugs were extracted with water and the extracts were used to grow Aspergillus parasiticus. All extracts reduced aflatoxin B(1) and aflatoxin G(1) production by 62-97%. All but two of the extracts reduced aflatoxin B(2) and aflatoxin G(2) production by 39-95%. It can be concluded that the commercial powdered mixed herbal drugs contained low number of endogenous fungi, and these drugs are inhibitory to the growth of its endogenous fungi and aflatoxins production by aflatoxigenic fungi.

Matched MeSH terms: Aspergillus/metabolism
The investigation of media components for optimal metabolite production of Aspergillus terreus ATCC 20542

Abd Rahim MH, Lim EJ, Hasan H, Abbas A

J Microbiol Methods, 2019 09;164:105672.
PMID: 31326443 DOI: 10.1016/j.mimet.2019.105672

PURPOSE: This study aimed to assess the effect of nitrogen, salt and pre-culture conditions on the production of lovastatin in A. terreus ATCC 20542.
METHODS: Different combinations of nitrogen sources, salts and pre-culture combinations were applied in the fermentation media and lovastatin yield was analysed chromatographically.
RESULT: The exclusion of MnSO4 ·5H2O, CuSO4·5H2O and FeCl3·6H2O were shown to significantly improve lovastatin production (282%), while KH2PO4, MgSO4·7H2O, and NaCl and ZnSO4·7H2O were indispensable for good lovastatin production. Simple nitrogen source (ammonia) was unfavourable for morphology, growth and lovastatin production. In contrast, yeast extract (complex nitrogen source) produced the highest lovastatin yield (25.52 mg/L), while powdered soybean favoured the production of co-metabolites ((+)-geodin and sulochrin). Intermediate lactose: yeast extract (5:4) ratio produced the optimal lovastatin yield (12.33 mg/L) during pre-culture, while high (5:2) or low (5:6) lactose to yeast extract ratio produced significantly lower lovastatin yield (7.98 mg/L and 9.12 mg/L, respectively). High spore concentration, up to 107 spores/L was shown to be beneficial for lovastatin, but not for co-metabolite production, while higher spore age was shown to be beneficial for all of its metabolites.
CONCLUSION: The findings from these investigations could be used for future cultivation of A. terreus in the production of desired metabolites.

Matched MeSH terms: Aspergillus/metabolism*
Improved lovastatin production by inhibiting (+)-geodin biosynthesis in Aspergillus terreus

Hasan H, Abd Rahim MH, Campbell L, Carter D, Abbas A, Montoya A

N Biotechnol, 2019 Sep 25;52:19-24.
PMID: 30995533 DOI: 10.1016/j.nbt.2019.04.003

Lovastatin is widely prescribed to reduce elevated levels of cholesterol and prevent heart-related diseases. Cultivation of Aspergillus terreus (ATCC 20542) with carbohydrates or low-value feedstocks such as glycerol produces lovastatin as a secondary metabolite and (+)-geodin as a by-product. An A. terreus mutant strain was developed (gedCΔ) with a disrupted (+)-geodin biosynthesis pathway. The gedCΔ mutant was created by inserting the antibiotic marker hygromycin B (hyg) within the gedC gene that encodes emodin anthrone polyketide synthase (PKS), a primary gene responsible for initiating (+)-geodin biosynthesis. The effects of emodin anthrone PKS gene disruption on (+)-geodin and lovastatin biosynthesis and the production of the precursors acetyl-CoA and malonyl-CoA were investigated with cultures based on glycerol alone and in combination with lactose. The gedCΔ strain showed improved lovastatin production, particularly when cultivated on the glycerol-lactose mixture, increasing lovastatin production by 80% (113 mg/L) while simultaneously inhibiting (+)-geodin biosynthesis compared to the wild-type strain. This study thus shows that suppression of the (+)-geodin pathway increases lovastatin yield and demonstrates a practical approach of manipulating carbon flux by modulating enzyme activity.

Matched MeSH terms: Aspergillus/metabolism*
Polyphasic approach to the identification and characterization of aflatoxigenic strains of Aspergillus section Flavi isolated from peanuts and peanut-based products marketed in Malaysia

Norlia M, Jinap S, Nor-Khaizura MAR, Son R, Chin CK, Sardjono

Int J Food Microbiol, 2018 Oct 03;282:9-15.
PMID: 29885975 DOI: 10.1016/j.ijfoodmicro.2018.05.030

Peanuts are widely consumed as the main ingredient in many local dishes in Malaysia. However, the tropical climate in Malaysia (high temperature and humidity) favours the growth of fungi from Aspergillus section Flavi, especially during storage. Most of the species from this section, such as A. flavus, A. parasiticus and A. nomius, are natural producers of aflatoxins. Precise identification of local isolates and information regarding their ability to produce aflatoxins are very important to evaluate the safety of food marketed in Malaysia. Therefore, this study aimed to identify and characterize the aflatoxigenic and non-aflatoxigenic strains of Aspergillus section Flavi in peanuts and peanut-based products. A polyphasic approach, consisting of morphological and chemical characterizations was applied to 128 isolates originating from raw peanuts and peanut-based products. On the basis of morphological characters, 127 positively identified as Aspergillus flavus, and the other as A. nomius. Chemical characterization revealed six chemotype profiles which indicates diversity of toxigenic potential. About 58.6%, 68.5%, and 100% of the isolates are positive for aflatoxins, cyclopiazonic acid and aspergillic acid productions respectively. The majority of the isolates originating from raw peanut samples (64.8%) were aflatoxigenic, while those from peanut-based products were less toxigenic (39.1%). The precise identification of these species may help in developing control strategies for aflatoxigenic fungi and aflatoxin contamination in peanuts, especially during storage. These findings also highlight the possibility of the co-occurrence of other toxins, which could increase the potential toxic effects of peanuts.

Matched MeSH terms: Aspergillus/metabolism
Aspergillus terreus treated rice straw suppresses methane production and enhances feed digestibility in goats

Mohd Azlan P, Jahromi MF, Ariff MO, Ebrahimi M, Candyrine SCL, Liang JB

Trop Anim Health Prod, 2018 Mar;50(3):565-571.
PMID: 29150805 DOI: 10.1007/s11250-017-1470-x

The objectives of this study were to test the efficacy of producing lovastatin in rice straw treated with Aspergillus terreus in larger laboratory scale following the procedure previously reported and to investigate the effectiveness of the treated rice straw containing lovastatin on methane mitigation in goats. The concentration of lovastatin in the treated rice straw was 0.69 ± 0.05 g/kg dry matter (DM) rice straw. Our results showed that supplementation of lovastatin at 4.14 mg/kg BW reduced methane production by 32% while improving the DM digestibility by 13% (P

Matched MeSH terms: Aspergillus/metabolism*
Molecular identification of Aspergillus and Eurotium species isolated from rice and their toxin-producing ability

Yazdani D, Zainal Abidin MA, Tan YH, Kamaruzaman S

Mikrobiologiia, 2011 Sep-Oct;80(5):707-13.
PMID: 22168015

Thirty milled rice samples were collected from retailers in 4 provinces of Malaysia. These samples were evaluated for Aspergillus spp. infection by direct plating on malt extract salt agar (MESA). All Aspergillus holomorphs were isolated and identified using nucleotide sequences of ITS 1 and ITS 2 of rDNA. Five anamorphs (Aspergillus flavus, A. oryzae, A. tamarii, A. fumigatus and A. niger) and 5 teleomorphs (Eurotium rubrum, E. amstelodami, E. chevalieri, E. cristatum and E. tonophilum) were identified. The PCR-sequencing based technique for sequences of ITS 1 and ITS 2 is a fast technique for identification of Aspergillus and Eurotium species, although it doesn't work flawlessly for differentiation of Eurotium species. All Aspergillus and Eurotium isolates were screened for their ability to produce aflatoxin and ochratoxin A (OTA) by HPLC and TLC techniques. Only A. flavus isolate UPM 89 was able to produce aflatoxins B1 and B2.

Matched MeSH terms: Aspergillus/metabolism
Fulltext Microbial keratitis: aetiological diagnosis and clinical features in patients admitted to Hospital Universiti Sains Malaysia

Norina TJ, Raihan S, Bakiah S, Ezanee M, Liza-Sharmini AT, Wan Hazzabah WH

Singapore Med J, 2008 Jan;49(1):67-71.
PMID: 18204773

Corneal ulceration remains one of the major causes of blindness in developing countries, including Malaysia. Our objective is to determine the epidemiological characteristics, clinical features, risk factors and the aetiology of microbial keratitis in patients admitted to Hospital Universiti Sains Malaysia (HUSM).

Matched MeSH terms: Aspergillus/metabolism
Fulltext Inactivating pathogenic bacteria in greywater by biosynthesized Cu/Zn nanoparticles from secondary metabolite of Aspergillus iizukae; optimization, mechanism and techno economic analysis

Noman E, Al-Gheethi A, Talip BA, Mohamed R, Kassim AH

PLoS One, 2019;14(9):e0221522.
PMID: 31513594 DOI: 10.1371/journal.pone.0221522

The inactivation of antibiotic resistant Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) seeded in greywater by bimetallic bio-nanoparticles was optimized by using response surface methodology (RSM). The bimetallic nanoparticles (Cu/Zn NPs) were synthesized in secondary metabolite of a novel fungal strain identified as Aspergillus iizukae EAN605 grown in pumpkin medium. Cu/Zn NPs were very effective for inhibiting growth of E. coli and S. aureus. The maximum inactivation was optimized with 0.028 mg mL-1 of Cu/Zn NPs, at pH 6 and after 60 min, at which the reduction of E. coli and S. aureus was 5.6 vs. 5.3 and 5.2 vs. 5.4 log reduction for actual and predicted values, respectively. The inactivation mechanism was described based on the analysis of untreated and treated bacterial cells by Field emission scanning electron microscopy (FESEM), Energy Dispersive X-Ray Spectroscopy (EDS), Atomic Force Microscopy (AFM) revealed a damage in the cell wall structure due to the effect of Cu/Zn NPs. Moreover, the Raman Spectroscopy showed that the Cu/Zn NPs led to degradation of carbohydrates and amino structures on the bacteria cell wall. The Fourier transform infrared spectroscopy (FTIR) analysis confirmed that the destruction take place in the C-C bond of the functional groups available in the bacterial cell wall. The techno economic analysis revealed that the biosynthesis Cu/Zn NPs is economically feasible. These findings demonstrated that Cu/Zn NPs can effectively inhibit pathogenic bacteria in the greywater.

Matched MeSH terms: Aspergillus/metabolism
Fulltext Lovastatin production by Aspergillus terreus using agro-biomass as substrate in solid state fermentation

Jahromi MF, Liang JB, Ho YW, Mohamad R, Goh YM, Shokryazdan P

J Biomed Biotechnol, 2012;2012:196264.
PMID: 23118499 DOI: 10.1155/2012/196264

Ability of two strains of Aspergillus terreus (ATCC 74135 and ATCC 20542) for production of lovastatin in solid state fermentation (SSF) using rice straw (RS) and oil palm frond (OPF) was investigated. Results showed that RS is a better substrate for production of lovastatin in SSF. Maximum production of lovastatin has been obtained using A. terreus ATCC 74135 and RS as substrate without additional nitrogen source (157.07 mg/kg dry matter (DM)). Although additional nitrogen source has no benefit effect on enhancing the lovastatin production using RS substrate, it improved the lovastatin production using OPF with maximum production of 70.17 and 63.76 mg/kg DM for A. terreus ATCC 20542 and A. terreus ATCC 74135, respectively (soybean meal as nitrogen source). Incubation temperature, moisture content, and particle size had shown significant effect on lovastatin production (P < 0.01) and inoculums size and pH had no significant effect on lovastatin production (P > 0.05). Results also have shown that pH 6, 25°C incubation temperature, 1.4 to 2 mm particle size, 50% initial moisture content, and 8 days fermentation time are the best conditions for lovastatin production in SSF. Maximum production of lovastatin using optimized condition was 175.85 and 260.85 mg/kg DM for A. terreus ATCC 20542 and ATCC 74135, respectively, using RS as substrate.

Matched MeSH terms: Aspergillus/metabolism*