Transportation of citrinin is regulated by the CtnC gene in the medicinal fungus Monascus purpureus / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Monascus is one of the most essential microbial resources in China, with thousands of years of history. Modern science has proved that Monascus can produce pigment, ergosterol, monacolin K, γ-aminobutyric acid, and other functionally active substances. Currently, Monascus is used to produce a variety of foods, health products, and pharmaceuticals, and its pigments are widely used as food additives. However, Monascus also makes a harmful polyketide component called citrinin in the fermentation process; citrinin has toxic effects on the kidneys such as teratogenicity, carcinogenicity, and mutagenicity (Gong et al., 2019). The presence of citrinin renders Monascus and its products potentially hazardous, which has led many countries to set limits and standards on citrinin content. For example, the citrinin limit is less than 0.04 mg/kg according to the Chinese document National Standard for Food Safety Food Additive Monascus (GB 1886.181-2016) (National Health and Family Planning Commission of the People's Republic of China, 2016), and the maximum level in food supplements based on rice fermented with Monascus purpureus is 100 µg/kg in the European Union (Commission of the European Union, 2019).

A novel citrinin derivative from the marine-source fungus Penicillium citrinum / 药学学报

A novel citrinin derivative, penicitrinol L (1), along with two known analogues, penidicitrinin B (2) and pennicitrinone A (3) were isolated from the marine-source fungus Penicillium citrinum. The structure of the new compound was elucidated by spectroscopic methods including one and two-dimensional NMR as well as high-resolution mass spectrometric analysis. Furthermore, compound 1 showed modest cytotoxic activity against HL-60 cell line and compound 3 showed weak cytotoxic activity against A375 cell line.

Effect of feeding graded doses of Citrinin on clinical and teratology in female Wistar rats.

Citrinin is the one of the well-known mycotoxins, which is possibly spread all over the world. The graded doses of citrinin (1, 3 and 5 ppm CIT in feed) in female Wistar rats 10 weeks prior to mating, during mating and during organogenesis resulted in resorptions and post implantation losses, decreased fetal body weights and crown-rump lengths in fetuses of all groups. Various developmental anomalies recorded in fetuses of treated rats included gross (wrist drop, curled tail, stretched forelimb, subcutaneous haematoma), skeletal (incomplete ossification of skull bones, incomplete fusion of vertebral bodies, complete and partial agenesis of sternaebrae, metacarpals, metatarsals and phalanges, fused ribs and swing out ribs) and visceral (internal and external hydrocephalus, cerebellar hypoplasia, microphthalmia, roundening of heart, contracted kidneys, dilated renal pelvis and cryptorchid testes). The results suggest that CIT has adverse effects on fetal development which may be due to the longer bioavailability of citrinin in the animals.

Cytotoxic and antibacterial substances against multi-drug resistant pathogens from marine sponge symbiont: Citrinin, a secondary metabolite of Penicillium sp

<p><b>OBJECTIVE</b>To Isolate, purify, characterize, and evaluate the bioactive compounds from the sponge-derived fungus Penicillium sp. FF001 and to elucidate its structure.</p><p><b>METHODS</b>The fungal strain FF001 with an interesting bioactivity profile was isolated from a marine Fijian sponge Melophlus sp. Based on conidiophores aggregation, conidia development and mycelia morphological characteristics, the isolate FF001 was classically identified as a Penicillium sp. The bioactive compound was identified using various spectral analysis of UV, high resolution electrospray ionization mass spectra, 1H and 13C NMR spectral data. Further minimum inhibitory concentrations (MICs) assay and brine shrimp cytotoxicity assay were also carried out to evaluate the biological properties of the purified compound.</p><p><b>RESULTS</b>Bioassay guided fractionation of the EtOAc extract of a static culture of this Penicillium sp. by different chromatographic methods led the isolation of an antibacterial, anticryptococcal and cytotoxic active compound, which was identified as citrinin (1). Further, citrinin (1) is reported for its potent antibacterial activity against methicillin-resistant Staphylococcus aureus (S. aureus), rifampicin-resistant S. aureus, wild type S. aureus and vancomycin-resistant Enterococcus faecium showed MICs of 3.90, 0.97, 1.95 and 7.81 µg/mL, respectively. Further citrinin (1) displayed significant activity against the pathogenic yeast Cryptococcus neoformans (MIC 3.90 µg/mL), and exhibited cytotoxicity against brine shrimp larvae LD50 of 96 µg/mL.</p><p><b>CONCLUSIONS</b>Citrinin (1) is reported from sponge associated Penicillium sp. from this study and for its strong antibacterial activity against multi-drug resistant human pathogens including cytotoxicity against brine shrimp larvae, which indicated that sponge associated Penicillium spp. are promising sources of natural bioactive metabolites.</p>

Immuno-affinity chromatographic purification: the study of methods to test citrinin in monascus products by high performance liquid chromatography / 中华预防医学杂志

<p><b>OBJECTIVE</b>To establish a method to test citrinin (CIT) in monascus products by immuno-affinity chromatography (IAC)-high performance liquid chromatography (HPLC), and to detect the content of CIT in monascus products in Fujian province.</p><p><b>METHODS</b>IAC-HPLC was applied to detect the CIT content in monascus products. The conditions to use HPLC were as follows: C(18) reversed-phase chromatographic column, 150.0 mm×4.6mm×3 µm; mobile phase: the volume ratio of acetonitrile and 0.1% phosphoric acid solution at 65:35; isocratic elution; column temperature: 28°C; flow velocity: 0.8 ml/min; fluorescence detector, excitation wavelength (λ(ex)) was 331 nm and emission wavelength (λ(em)) was 500 nm. The standard curved was established by the linear regression of peak area (Y) to CIT content (X, ng/ml). The accuracy and precision of the method would then be verified. And 32 kinds of monascus products were determined and their color values were compared by this method.</p><p><b>RESULT</b>The standard curve established in this study was Y = 4634.8X-136.42, r = 1.000; whose limits of detection was 20 µg/kg and the limits of qualification was 64 µg/kg. In the range between 200 and 800 µg/kg, the standard recovery rate was 98.9% - 110.0% (n = 3), and the relative standard deviation (RSD) was 0.51% - 1.76%. Out of the 32 samples, CIT was detected from 11 samples of monascus rice, 9 samples of monascus powder and 5 samples of monascus pigments, the content was around 0.212 - 14.500 mg/kg. 4 out of 7 functional monascus samples were detected out CIT, whose content at 0.142 - 0.275 mg/kg.</p><p><b>CONCLUSION</b>The method to detect CIT in monascus products by IAC-HPLC has been established.</p>

Preparation of artificial antigen and egg yolk-derived immunoglobulin (IgY) of citrinin for enzyme-linked immunosorbent assay / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To prepare artificial antigens and anti-citrinin egg yolk-derived immunoglobulin (IgY) to build an enzyme-linked immunosorbent assay (ELISA) for citrinin (CTN).</p><p><b>METHODS</b>CTN was conjugated with bovine serum albumin (BSA), ovalbumin (OVA) with formaldehyde condensation method to prepare artificial antigens and identified by ultraviolet (UV) spectrometry and Infrared (IR) spectrometry. Artificial antigens for CTN and anti-CTN IgY were purified with polyethylene glycol two-step precipitation method and identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). ELISA with IgY was established. Cross-reactivity of IgY with various structural similarities to CTN and possible co-occurrence with CTN in agricultural commodities were studied.</p><p><b>RESULTS</b>UV and IR absorption spectra suggested that CTN was correlated with the carrier protein of BSA or OVA. SDS-PAGE patterns showed that the anti-CTN IgY was almost pure with a molecular weight of approximate 100 KD. The indirect competitive ELISA showed that the detection limit of CTN was 10 ng x mL(-1), with a good linearity ranging 20-640 ng x mL(-1).</p><p><b>CONCLUSION</b>Artificial antigens of CTN can be successfully synthesized. The established ELISA can be used to determine CTN- contaminated samples.</p>

Cloning and sequence analysis of the full-length cDNA of a novel yp05 gene associated with citrinin production in Monascus aurantiacus / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To obtain the full-length cDNA of a novel gene (named yp05) associated with citrinin production-related genes in Monascus aurantiacus.</p><p><b>METHODS</b>Total RNA was extracted from mycelium, 3' and 5' cDNA end of yp05 gene was amplified using smart trace cDNA amplification kit, and the full-length cDNA of a novel gene (named yp05) was obtained from the electronic assembly of 3'-RACE and 5'-RACE products.</p><p><b>RESULTS</b>This yp05 gene was 787 bp including a 597 bp open reading frame (ORF) and encoded a deduced protein with 199 amino acid residues, and the amino acid sequence of this protein was found similar with the sequences of many fungal manganese-superoxide dismutases in the GenBank with the aid of BLASTp. The transcription of yp05 gene in Monascus strains was analyzed with the aid of Northern blotting. The transcription of yp05 gene was only detected in Monascus strains, provided that citrinin was produced.</p><p><b>CONCLUSION</b>The transcription of yp05 gene belongs to differential expression genes of citrinin yielded from Monascus and has no correlation with the biosynthesis pathway of red pigments.</p>

Determination of citrinin in red kojic by HPCE / 中国中药杂志

<p><b>OBJECTIVE</b>To establish an instant determination method of citrinin in red kojic by high performance capillary electrophorphores for the first time.</p><p><b>METHOD</b>Red kojic was extracted with the mixtrue of Toluene and ethyl acetate (70:30). Separation was carried out in an uncoated fused silica capillary (50 microm x 45.0 cm). Meanwhile, a running voltage 15 kV, 20 mmol L(-1) borax buffer with 10.0 mmol L(-1) sodium deoxycholate (pH 9.3) and a UV detector at 212 nm were adopted.</p><p><b>RESULT</b>Regression equation of citrinin was Y=9434 + 16781X (r =0.990), The lower limit of quantification (S/N > or =3) was 0.5 mg mL(-1). The assay coefficients of variation ranged from 98.8% to 101.1%. The intra and inter recovery ranged from 0.83 to 1.54% and from 1.86 to 5.09%. Twenty samples were determined with the method.</p><p><b>CONCLUSION</b>The method is proved to be simple, rapid and accurate, and it can be used to determine citrinin in red kojic.</p>

Supressão da resposta imunitária humoral causada pela citrinina / Humoral immunosupression caused by citrinin

Avaliou-se o efeito imunotóxico causado por exposição a baixas doses de citrinina (2,5mg kg-1) em camundongos albinos expostos à micotoxina antes (n=15), durante (n=15) e após (n=15) a imunização com antígeno inerte, representado por eritrócitos de carneiro - sheep red blood cells (SRBC). Quinze camundongos foram usados como controle (não intoxicados). Sete dias após o tratamento, os animais foram sangrados e os títulos de anticorpos anti-SRBC e de complemento foram determinados. A citrinina diminuiu os títulos de anticorpos primários em todos os grupos intoxicados. A intoxicação antes e após a imunização provocou diminuição em 87,5 por cento nos títulos médios de anticorpos específicos. A exposição simultânea à imunização gerou diminuição de 75 por cento. Houve acentuada redução nos níveis de complemento circulante, detectada nos animais previamente intoxicados (93,8 por cento), ou intoxicados juntamente com a imunização (87,5 por cento).

Serial analysis of gene expression in Monascus aurantiacus producing citrinin / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To construct a tag expression library of Monascus aurantiacus that could produce citrinin maximally on the thirteenth (0.966 mg/mL) day in the submerged culture.</p><p><b>METHODS</b>Total RNA was extracted from the mycelium, cDNA was synthesized using the SuperScript choice system, and then, a SAGE library was successfully constructed according to the MicroSAGE method.</p><p><b>RESULTS</b>Five hundred and ninety eight clones were obtained in SAGE library, and 120 clones were picked out randomly for identification and sequencing purpose. Eighty nine clones had positive inserts, 26 clones had no inserts and the remaining 5 clones had no site of NlaIII enzyme in inserts. There were seven repeated clones.</p><p><b>CONCLUSION</b>With the aid of SAGE2000 software, 901 tags were obtained from 89 clones, representing 686 unique transcripts. Six unique tags of them belong to highly expressed genes (Number of tags > or = 10) and 143 unique tags to moderately expressed genes (repeat tags > or = 2).</p>

Effect of citrinin and in association with aflatoxin B1 on the infectivity and proliferation of Toxoplasma gondii in vitro

Macrophages exposed to 10 mug/mL citrinin (CTR) or 0.01 mug CTR mixed with 0.04 mug aflatoxin B1 (AFB1) for a period of 2 h at 37ºC, were infected with 10(6) Toxoplasma gondii tachyzoites/muL. The parasites were treated with mycotoxins (2 h at 37ºC) before being added to the macrophage culture. The number of tachyzoites was quantified 2, 24, 48, 72 and 96 h after infection. During the first 2 hours, 59 percent infectivity was observed in the control. After exposure to CTR or the mixture of toxins (CTR-AFB1), macrophages were infected with 77.5 percent and 75 percent of the inoculated tachyzoites, respectively. Similarly, 72.3 percent of the cells were infected when cultured together with previously treated parasites. The treatment with CTR-AFB1 gave rise to 2.9 times more tachyzoites than the control at 72 h. An increased number of parasites was recovered from macrophages exposed to CTR after 96 h, and to CTR-AFB1 after 72 h of culture; The number of tachyzoites recovered from the supernatant was 1.94 and 2.06 times higher, respectively, than in the control (5 x 10(5) ± 0.054 /mL).

Deficiências imunitárias por micotoxinas em camundongos C57BL/6, infectados com Toxoplasma gondii / Immunologic deficiencies for mycotoxins in mice C57BL/6, infected with Toxoplasma gondii

A adição de 0,04 mg/ml de Aflatoxina B1, 0,04mg/ml de Ocratoxina A, 0,01mg/ml de Citrinina e 0,05 mg/ml de Fumonisina B1, em combinações, sobre macrófagos murinos alteraram o número de placas hemolíticas contra eritrócitos de carneiro. A presença de soro heterólogo minimizou os efeitos imunosupressivos das micotoxinas. Macrófagos expostos às diferentes micotoxinas antes da infecção por T. gondii, permitiram investigar a infectividade relativa do protozoário sobre células intoxicadas. Todos os experimentos utilizando micotoxinas resultaram em um aumento da infecção por T. gondii.

Citrininotoxinogenicity of Penicillium spp, isolated from decaying apples

A study on the occurrence of citrinin and citrinin production ability of Penicillium spp. isolated from bactericidal effect.decaying apples collected from households in Croatia was carried out. Among 100 samples of apples, 37 strains of Penicillium spp. were found, including P. expansum, P. roqueforti, P. implicatum and P. purpurogenum. Citrinin production in liquid yeast medium by 11 strains of P. expansum varied in a range of 0.07 to 9.00 mg.kg-1. Citrinin was isolated from 19 per center of apple samples in range of 0.05 to 0.24 mg.kg-1. Antimicrobial activity of isolated citrinin, evaluated through tests on Bacillus subtilis, presented inhibitory zones varying from 5 mm to 1 cm. Minimal inhibitory concentrations (MIC) were 0.0072 µg.mL-1 for bacteriostatic effect, and 0.0144 µg.mL-1 for bactericidaleefect.

Ocratoxina A, aflatoxina B1 e citrina como agentes moduladores da produçäo de anticorpos em aves e mamíferos / Ochratoxin A, aflatoxin B1 and citrinin aas modulators agents of antibodies production in poultry and mammalian

O presente trabalho foi desenvolvido com o objetivo de demonstrar os efeitos causados pela associaçäo entre ocratoxina A, aflatoxina B1 e citrinina, sobre a resposta imunitária adaptativa de aves e mamíferos, a fim de determinar se estas micotoxinas poderiam levar à modulaçäo do sistema imune. A toxicidade relativa de cada micotoxina, bem como de suas associaçöes, foi determinada em células esplênicas de galinhas e camundongos, onde se observou a secreçäo primária de anticorpos (IgM) contra eritrócitos de carneiro, após quatro horas de exposiçäo às micotoxinas. Os ensaios foram realizados na presença e na ausência de soro heterólogo proveniente de animais adultos normais, a fim de determinar possíveis interaçöes entre o complemento presente no soro, com a açäo tóxica das micotoxinas. Observou-se uma notável depressäo imunológica nos grupos tratados com a associaçäo entre citrina e aflatoxina B1, porém, na presença de soro heterólogo, houve uma imunoestimulaçäo. Os resultados sugerem uma possível interferência de fatores inespecíficos, os quais estäo presentes no soro proveniente de animais adultos normais, cuja atividade poderia amenizar ou até mesmo neutralizar a açäo imunomodulatória das micotoxinas, sugerindo a possibilidade de imunoterapia.

Supressäo da resposta imunitária humoral causada por citrinina efeito imunotóxico da citrinina / Humoral immunoresponse discontinuance caused by citrinin

O presente trabalho foi realizado com a finalidade de avaliar o efeito imunotóxico causado por exposiçäo a baixas doses de citrinina (2,5mg.Kg(-1)). Para tanto, lotes de cinco camundongos albinos foram expostos à micotoxina antes, durante e após imunizaçäo com antígeno inerte (eritrócitos de carneiro - SRBC). Sete dias após tratamento, os animais foram sangrados e os títulos de anticorpos anti-SRBC e de complemento foram determinados, em relaçäo a um grupo controle näo intoxicado. Observou-se que a citrinina causou diminuiçäo nos títulos de anticorpos primários de todos os grupos de animais intoxicados. A intoxicaçäo antes e após à imunizaçäo provocou uma diminuiçäo nos títulos médios de anticorpos específicos equivalente a 87,5 por cento. A exposiçäo simultânea a imunizaçäo gerou uma diminuiçäo de 75 por cento. Houve, também, uma marcante reduçäo nos níveis de complemento circulante, detectada nos animais previamente intoxicados (93,75 por cento), ou intoxicados juntamente com a imunizaçäo (87,5 por cento). Os efeitos relativos da citrinina sobre populaçöes linfocitárias e sobre os processos inflamatórios e de apresentaçäo de antígenos também foram discutidos.

Introducción al tema de micotoxinas y micotoxicosis / Introduction to mycotoxins and mycotoxicoses

Se presenta un panorama general sobre las principales micotoxinas y sus efectos sobre la salud humana y animal