Anticancer potential of NF-κB targeting apoptotic molecule "flavipin" isolated from endophytic Chaetomium globosum.

BACKGROUND: Anticancer compounds from natural sources have drawn attention due to their structural diversity and relatively lesser side effects. Endophytic fungi are one such natural resource from, which plethoras of anticancerous compounds have been isolated. PURPOSE: The objective of the study was to isolate and characterize the bioactive metabolite from Chaetomium globosum that exhibits astonishing antiproliferative activity against cancerous cell lines. METHODS: Flavipin was isolated by bioassay-guided fractionation and identified using FT-IR, EI-MS and NMR studies. MTT assay was used to determine the cytotoxicity. Fluorescent staining (AO/EB) and DNA fragmentation studies confirmed the occurrence of apoptosis. Real time PCR and Western blotting were used to analyze the expression of apoptosis related genes and its proteins, respectively. RESULTS: Flavipin inhibited proliferation of A549, HT-29 and MCF-7 cancer cells in dose dependent manner with an IC50 concentration of 9.89 µg/ml, 18 µg/ml and 54 µg/ml, respectively, whereas it was comparatively less sensitive (IC50 = 78.89 µg/ml) against normal cell line (CCD-18Co). At IC50 concentration cancerous cells exhibited cell shrinkage and fragmentation of DNA, which indicated that flavipin induced apoptotic cell death. In treated cells there is an up-regulation of p53 gene and its associated protein, whereas reciprocal expression was observed in BCL-2 gene and its protein. Furthermore, western blotting results also showed down-regulation of NFκB. CONCLUSION: This is the first report on the antiproliferative activity of flavipin isolated from endophytic C. globosum and also proposed that interaction of flavipin with NFкB could be a possible mechanism for this activity. Flavipin induced apoptosis at low concentrations in cancer cell lines (A549, HT-29) and exhibited itself as a potential anticancer agent.

Characterization, culture medium optimization and antioxidant activity of an endophytic vitexin-producing fungus Dichotomopilus funicola Y3 from pigeon pea [Cajanus cajan (L.) Millsp.].

AIMS: The aim of this study was to characterize a fungal endophyte Y3 from pigeon pea (Cajanus cajan [L.] Millsp), as a novel producer of vitexin, and its culture medium optimization and antioxidant activity. METHODS AND RESULTS: The endophyte from the leaves of pigeon pea was identified as Dichotomopilus funicola by the morphological and molecular characteristics. The most important medium variables affecting vitexin production in liquid culture of D. funicola Y3 were screened by Plackett-Burman design, and three culture medium constituents (i.e. l-phenylalanine, salicylic acid and CuSO4 ·5H2 O) were identified to play significant roles in vitexin production. The most significant factors were further optimized using by central composite design with response surface methodology. The DPPH radical-scavenging assay indicated that fungal vitexin exhibited notable antioxidant activity with an EC50 value of 164 µg l-1 . CONCLUSIONS: First, a novel endophyte vitexin-producing Dichotomopilus funicola Y3 was isolated from pigeon pea (Cajanus cajan[L.] Millsp.). The maximum vitexin yield was obtained as 78·86 mg l-1 under the optimum culture medium constituents: 0·06 g l-1  l-phenylalanine, 0·21 g l-1 salicylic acid, and 0·19 g l-1 CuSO4 ·5H2 O in medium, which is 4·59-fold higher than that in the unoptimized medium. Also, fungal vitexin clearly demonstrated its antioxidant potential. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings provide an alternative source for large-scale production of vitexin by endophytic fungal fermentation and have a promising prospect in food and pharmaceutical industry.

Polyphasic characterisation of Chaetomium species from soil and compost revealed high number of undescribed species.

This study investigated 46 Chaetomium strains isolated from soil and compost from China. In total 14 species were recognised, of which seven were described as new species (i.e. Chaetomium angulare, Chaetomium cirrhata, Chaetomium heterothallicum, Chaetomium laterale, Chaetomium longiciliata, Chaetomium microthecia, Chaetomium uniseriatum). Growth temperature profiles of these fungi revealed that 11 species are mesophilic; C. angulare and Chaetomium jodhpurense are thermotolerant; Chaetomium thermophilum var. dissitum is thermophilic, with temperature maxima above 50 °C. Among the 46 strains, 39 were shown to be homothallic. Mating experiments were conducted for the remaining seven strains that are morphologically and phylogenetically closely related. The results of the mating experiment, together with the four-locus (ITS, LSU, RPB2, TUB) phylogeny and a pairwise homoplasy index (PHI) test, supported the division of these seven additional strains into two heterothallic species that are herein described as C. heterothallicum and C. uniseriatum. A three-locus (ITS, LSU, TUB) phylogenetic tree based on all currently accepted species that have available type-derived sequences revealed that Chaetomium species clearly grouped in six phylogenetic groups which showed a certain correspondence with their morphology and temperature profiles.

Cytoglobosins H and I, New Antiproliferative Cytochalasans from Deep-Sea-Derived Fungus Chaetomium globosum.

Cytoglobosins H (1) and I (2), together with seven known cytochalasan alkaloids (3-9), were isolated from the deep-sea-derived fungus Chaetomium globosum. The structures of new compounds 1 and 2 were elucidated by extensive 1D and 2D NMR and mass spectroscopic data. All the compounds were evaluated for their antiproliferative activities against MDA-MB-231 human breast cancer cells, LNCaP human prostate cancer cells, and B16F10 mouse melanoma cells. Compound 6 showed significant antiproliferative activity against LNCaP and B16F10 cell lines with IC50 values of 0.62 and 2.78 µM, respectively. Further testing confirmed that compound 6 inhibited the growth of LNCaP cells by inducing apoptosis.

Endophytic fungus strain 28 isolated from Houttuynia cordata possesses wide-spectrum antifungal activity

Abstract The aim of this paper is to identify and investigate an endophytic fungus (strain 28) that was isolated from Houttuynia cordata Thunb, a famous and widely-used Traditional Chinese Medicine. Based on morphological methods and a phylogenetic analysis of ITS sequences, this strain was identified as Chaetomium globosum. An antifungal activity bioassay demonstrated that the crude ethyl acetate (EtOAc) extracts of strain 28 had a wide antifungal spectrum and strong antimicrobial activity, particularly against Exserohilum turcicum (Pass.) Leonard et Suggs, Botrytis cinerea persoon and Botrytis cinerea Pers. ex Fr. Furthermore, the fermentation conditions, extraction method and the heat stability of antifungal substances from strain 28 were also studied. The results showed that optimal antifungal activity can be obtained with the following parameters: using potato dextrose broth (PDB) as the base culture medium, fermentation for 4–8 d (initial pH: 7.5), followed by extraction with EtOAc. The extract was stable at temperatures up to 80 °C. This is the first report on the isolation of endophytic C. globosum from H. cordata to identify potential alternative biocontrol agents that could provide new opportunities for practical applications involving H. cordata.

Invasive pulmonary mycosis due to Chaetomium globosum with false-positive galactomannan test: a case report and literature review.

In this case, the authors report Chaetomium globosum as a cause of invasive pulmonary infection in a patient with Wegener's granulomatosis. Fungal hyphae (KOH and Calcofluor) were seen on direct microscopy of lung biopsy sample and bronchoalveolar lavage (BAL) sample. C. globosum isolated on culture clinched the diagnosis of invasive pulmonary infection by Chaetomium spp. A positive galactomannan of serum and BAL was repeatedly seen and was utilised for follow-up and as prognostic marker in patient management. The patient was successfully treated with liposomal amphotericin B followed by voriconazole. All the Chaetomium infections reported till date since 1980 are reviewed. Chaetomium spp. with its unique ecology has a hidden clinical potential to cause invasive mould infections.

Rare case of subcutaneous mycosis with intrathoracic extension due to Chaetomium strumarium.

A 47-year-old man presented with a 10-year history of multiple lumps over his left upper arm and shoulder and the adjoining left side of his chest and upper back. His medical history included diabetes mellitus type 2. The patient was a farmer and used to lift sacks of grains and fertilizers onto his shoulders as part of his work, although he did not recollect any history of specific trauma. Skin biopsy revealed granulomatous reaction with Splendore-Hoeppli phenomenon, while periodic-acid-Schiff and Grocott-Gomori stains confirmed fungal elements. Sabouraud agar grew Chaetomium species, and lactophenol blue mount confirmed the fungus as Chaetomium strumarium. Radiography and computed tomography of the chest revealed intrathoracic extension of the mycetoma. The patient responded well to treatment with oral Itraconazole. Subcutaneous mycosis due to C. strumarium is rarely reported in the literature, and the intrathoracic extension makes it an even rarer entity.

Chemical constituents from the fungus Chaetomium cupreum RY202.

Two new angular types of azaphilones, isochromophilonol (1) and ochrephilonol (2), together with ten known compounds (3-12), were isolated from Chaetomium cupreum RY202. Their structures were established on the basis of spectroscopic data and the absolute configurations of 1 and 3 were determined by the modified Mosher's method. Compounds 1, 2 and 4 showed moderated cytotoxicity against KB and NCI-H187 cell lines (IC50 9.63-32.42 µg/mL).

Implantation phaeohyphomycosis caused by a non-sporulating Chaetomium species.

We report the case of a 66-year-old Iranian woman with a phaeohyphomycotic cyst (approximately 3×2.5cm in size) on the right lateral side of the neck. She had dysphagia and hoarseness, without any pain. She complained about discharge of black liquid on the skin and irritation. Histological examination of biopsy fragments from the lesions showed septate, branched brown hyphae. The fungus was cultured, but sporulation remained absent from 4- week-old cultures on Sabouraud dextrose agar (SDA), malt extract agar (MEA), potato dextrose agar (PDA), and water agar with sterile filter paper. Identification with the genus Chaetomium was achieved by sequencing the internal transcribed spacer (ITS) and the small subunit (SSU) domains of the rDNA gene and comparison with sequences held at GenBank and at the Centraalbureau voor Schimmelcultures (CBS). Sequencing of the SSU rRNA gene reveals this strain as belonging to the genus Chaetomium. The sequence of ITS did not fully match with any sequence of available ex-type strains of Chaetomium, Thielavia, Madurella and Papulaspora and hence might belong to an undescribed species. However, without diagnostic morphological features the taxon cannot be introduced as a novel member of the genus Chaetomium. After local excision of the cyst and antifungal therapy with ketoconazole (200mg twice a day), the lesion regressed and healed completely.

Flavipin in Chaetomium globosum CDW7, an endophytic fungus from Ginkgo biloba, contributes to antioxidant activity.

1,2-Benzenedicarboxaldehyde-3,4,5-trihydroxy-6-methyl (flavipin) was found to be antagonistic against nematodes and fungi. Here we demonstrated that flavipin is a potent antioxidant in vitro and in vivo, which has great potential in the therapy for free radical-associated diseases. Therefore, flavipin-producing bio-source was screened from 80 endophytes in Ginkgo biloba. Seven endophytic fungi were able to synthesize antioxidant substances and identified by ITS rDNA sequences. Among them, Chaetomium globosum CDW7 was a remarkable producer of flavipin. The fermentation parameters of CDW7 were then optimized for high flavipin production. Cultured under the optimal condition (25 °C, 100/250 mL flask, 12 discs/flask, 150 rpm, pH 6.5) for 14 days, CDW7 was able to synthesize flavipin at a production of 315.5 mg/L. In addition, flavipin output was positively correlated to antioxidant activities of crude extracts with a correlation coefficient of 0.8235, indicating that flavipin was the major antioxidant component of CDW7's metabolites. These data demonstrated that CDW7 was a highly yielded bio-source of antioxidant flavipin.

Isolamento de Chaetomium spp. em lesões subcutâneas de um cão: relato de caso / Isolation of Chaetomium spp. on subcutaneous lesions of a dog: case report

Caracterizou-se clinicamente a infecção pelo Chaetomium spp. em um cão, e descreveu-se seu isolamento e identificação. Ao exame dermatológico foram observadas pápulas nas orelhas, no tronco lateral e nos membros pélvicos. Ao rompimento de uma dessas pápulas, fluiu um líquido serosanguinolento com consequente úlcera no local. Foi colhido material para isolamento micológico, por meio de raspado das pápulas da orelha e da cauda. O diagnóstico foi micose subcutânea por Chaetomium spp.

This work aimed to clinically characterize the infection by Chaetomium spp. in a dog, as well as describe its isolation and identification. Upon dermatological exam, papules on ears, lateral trunk and pelvic members were noticed. After the disruption of these papules there was serosanguineous secretion flowed by consequent ulcer in the region. Material for mycological isolation was picked, and a scraping of papules from ear and tail was done. The diagnosis was subcutaneous mycosis caused by Chaetomium spp.

Bioactive metabolites from Chaetomium globosum L18, an endophytic fungus in the medicinal plant Curcuma wenyujin.

An endophytic fungus, strain L18, isolated from the medicinal plant Curcuma wenyujin Y.H. Chen et C. Ling was identified as Chaetomium globosum Kunze based on morphological characteristics and sequence data for the internal transcribed spacer (ITS-5.8S-ITS2) of the nuclear ribosomal DNA. A new metabolite named chaetoglobosin X (1), together with three known compounds erogosterol (2), ergosterol 5α,8-peroside (3) and 2-methyl-3-hydroxy indole (4), were isolated from C. globosum L18. Their structures were elucidated by spectroscopic methods including NMR, UV, IR and MS data and comparison with published data. Chaetoglobosin X (1) is hitherto unknown, whereas 2-methyl-3-hydroxy indole (4) is reported for the first time as a fungal metabolite, and erogosterol (2) and ergosterol 5α,8-peroside (3) are known fungal metabolites previously identified in other genera. Chaetoglobosin X (1) exhibited a broader antifungal spectrum and showed the strongest cytotoxic activity against H22 and MFC cancer cell lines.

Phaeohyphomycosis and onychomycosis due to Chaetomium spp., including the first report of Chaetomium brasiliense infection.

Chaetomium species have been rarely described as aetiological agents of invasive and dermatomycotic infections in humans. The majority of cases have been reported within the last two decades. Treatment failed in most of these cases. In this paper we present two cases in which Chaetomium spp. can be clearly identified as an aetiological agent in pathological conditions. In the first report, we describe a new aetiological agent, Chaetomium brasiliense, which was implicated in a case of otitis externa in a patient with spinocellular carcinoma basis cranii. The patient had been repeatedly treated for relapsing otitis externa and had previously undergone surgery several times for otitis media. The fungal aetiology was confirmed by repeated positive culture and histologic studies. The second case involved onychomycosis with strikingly brown nail discoloration due to Chaetomium globosum in an otherwise healthy patient. The nail lesion was successfully cured by oral terbinafine. The determination of both species was supported by sequencing of rDNA regions. The morphological aspect of Chaetomium spp. identification is also discussed. In vitro antifungal susceptibility tests demonstrated that both isolates were susceptible to terbinafine and azole derivates except fluconazole. Amphotericin B was effective only against the C. brasiliense strain. We review the literature to summarize clinical presentations, histologic findings, and treatment strategies.

Cytotoxic activities of endophytic fungi isolated from the endangered, Chinese endemic species Dysosma pleiantha.

Eleven strains of endophytic fungi which habitat in an endangered, Chinese endemic medicinal plant, Dysosma pleiantha (Hance) Woodson, were isolated and tested for their cytotoxic activity using the brine shrimp lethality bioassay. Six isolates were found to exhibit some cytotoxic activity. Extracts of F1273, F1276, and F1280, which were identified as Trichoderma citrinoviride, Chaetomium globosum and Ascomycete sp., in particular, showed most potent activity with LC50 values of 4.86, 7.71, and 14.88 microg/ml, respectively. These results indicate that endophytic fungi of Dysosma pleiantha could be a promising source for antitumour agents.

A new tetrahydrofuran derivative from the endophytic fungus Chaetomium sp. isolated from Otanthus maritimus.

A hitherto unidentified endophytic strain of the genus Chaetomium, isolated from the medicinal plant Otanthus maritimus, yielded a new tetrahydrofuran derivative, aureonitolic acid (1), along with 5 known natural products, 2-6. The structure of 1 was determined by extensive spectroscopic analysis and comparison with reported data. Extracts of the fungus, grown either in liquid culture or on solid rice media, exhibited considerable cytotoxic activity when tested in vitro against L5178Y mouse lymphoma cells. Compounds 2 and 6 showed significant growth inhibition against L5178Y cells with EC50 values of 7.0 and 2.7 microg/mL, respectively, whereas 1 was inactive.

Chaetomugilins, new selectively cytotoxic metabolites, produced by a marine fish-derived Chaetomium species.

Chaetomugilins A-F have been isolated from a strain of Chaetomium globosum originally isolated from the marine fish Mugil cephalus, and their absolute stereostructures have been elucidated on the basis of spectroscopic analyses, including 1D and 2D NMR techniques, some chemical transformations and an X-ray analysis. These compounds exhibited significant growth inhibition against cultured P388 cells and HL-60 cells. In addition, chaetomugilins A, C and F showed selective cytotoxic activities against 39 human cancer cell lines.

Chromoblastomycosis caused by Chaetomium funicola: a case report from Western Panama.

Little is known about opportunistic fungi causing skin lesions in tropical countries such as Panama. We report an 83-year-old man from Chiriquí, Western Panama, with crusted skin lesions covering tumorous masses resembling Bowen's disease of the skin on the dorsum of his right hand. Fungal cultures were obtained on different nutrient media from disinfected superficial skin scrapings and fragments taken from a deep skin biopsy. Deep skin biopsy showed the presence of globose, dark fungal cells in the upper and lower dermis, sometimes in abscesses or giant cells, indicating chromoblastomycosis. All fungal fragments plated on nutrient media yielded colonies of Chaetomium funicola which was identified based on morphological observations and molecular sequence data of large ribosomal subunit rDNA. Treatment with fluconazole was ineffective. Further treatments could not be applied because of the patient's advanced age, low compliance, and limited resources in a rural, tropical environment. For the first time, C. funicola is confirmed as an opportunistic fungus causing superficial and deep cutaneous lesions. Up to now, the only known clinical record of this species is a tentative identification as an agent of deep mycosis.

Invasive chaetomium infection in two immunocompromised pediatric patients.

The majority of fungal infections are caused by species such as Candida and Aspergillus. Other rare and emerging opportunistic fungal infections are on the increase. Risk factors for such infections include receipt of antimicrobial agents, chemotherapy, immunosuppression secondary to hematopoietic stem cell or solid organ transplantation, neutropenia, presence of indwelling intravascular catheter, prior hemodialysis, or previous fungal colonization. We present here the first 2 reports of fatal and invasive Chaetomium infections in pediatric patients. The first case occurred in a child with acute myeloid leukemia (AML) and the other in a child with hemophagocytic syndrome (HSP).