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ABSTRACTNatural pigments derived from microorganisms have many advantages and are widely studied in the food industry. A filamentous fungus, DBFL05, was identified as Aspergillus ustus, which produces a bright and abundant brown pigment. This extracellular, water-soluble pigment is highly polar and slightly soluble in alcohol but insoluble in other organic solvents. The pigment is stable under sunlight, at pH 2–10, and below 100°C. However, it is sensitive to Zn2+, Fe3+, Fe2+, and Cu2+. The pigment is mainly composed of two chemical components, pyrropyrazine diketone and dianthrone, and is classified as a polyketone pigment. Both components of the pigment exhibit inhibitory effects on bacteria and scavenging abilities for •OH and DPPH. The pigment showed no significant toxicity to plants and low toxicity to brine shrimp larvae. These findings indicate that the easily obtainable A. ustus pigment is a polyketone with attractive colour, stability, safety, and bioactivity.

Four new drimane sesquiterpenoids (1–4) and three known ones (5–7) were isolated from the fermentation broth of the mangrove-derived Aspergillus ustus 094102. Compound 5 was further resolved as four purified compounds 5a–5d. By means of extensive spectroscopic and ECD analysis as well as the chemical transformation, their structures were identified as (2R,3R,5S,9R,10S)-2,3,9,11-tetrahydroxydrim-7-en-6-one (ustusol F, 1), (2R,3R,5R,9S,10R)-2,3,11-trihydroxydrim-7-en-6-one (9-deoxyustusol F, 2), (3S,5R,9R,10R)-3,11,12-trihydroxydrim-7-en-6-one (ustusol G, 3), (5S,6R,9S,10S, 11R,2′E,4′E)-(11-dideoxy-11-hydroxystrobilactone A-6-yl)-5-carboxypenta-2,4-dienoate (ustusolate H, 4), ((5S,6R,9S,10S)-strobilactone A-6-yl) (2E,4E)-6,7-dihydroxyocta-2,4-dienoate (ustusolate I, 5), (2′E,4′E;6′,7′-erythro)-ustusolate I (5a) and (2′E,4′E;ent-6′,7′-erythro)-ustusolate I (5b), (2′E,4′E,6′R,7′R)-ustusolate I (5c) and (2′E,4′E,6′S,7′S)-ustusolate I (5d), (5S,6R,9S,10S,2′E,4′E)-(strobilactone A-6-yl)-5-carboxypenta-2,4-dienoate (ustusolate J, 6), and (2S,5S,9R,10S)-2,9,11-trihydroxydrim-7-en-6-one (ustusol B, 7), respectively. Compound 5 showed antiproliferation against the human tumor cells CAL-62 and MG-63 with the IC50 values of 16.3 and 10.1 µM, respectively.

The Aspergilli of section Usti (group ustus) are represented by over 20 species, of which Aspergillus calidoustus is the most relevant human pathogen. Invasive aspergillosis (IA) caused by these fungi is rare but could represent an emerging issue among the expanding population of patients with long-term immunosuppression receiving antifungal prophylaxis. Clinicians should be aware of this unusual type of IA, which often exhibits distinct clinical features, such as an insidious and prolonged course and a high occurrence of extra-pulmonary manifestations, such as skin/soft tissue or brain lesions. Moreover, these Aspergillus spp. pose a therapeutic challenge because of their decreased susceptibility to azole drugs. In this review, we outline the microbiological and clinical characteristics of IA due to Aspergillus spp. of section Usti and discuss the therapeutic options.

The deterioration of wood on account of microbiological agents is an acknowledged fact. Botryodiplodia theobromae - Trichoderma longibrachiatum - Aspergillus candidus - Aspergillus ustus and Aspergillus terreus were isolated from two wooden masks dating back to the Greek- Roman period in Egypt. The chemical composition of wood is easily affected after any attack and visible changes can be noticed clearly after some time, but the degree of deterioration of wood constituents cannot be estimated unless the wood is closely studied. Ficus sycomorus wood samples, which had been infected by the fungi isolated from the masks, were studied by using X Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy with Attenuation Total Reflection (FTIR-ATR).

ABSTRACT The fungus Aspergillus ustus was isolated from external ear inflammation. This fungus rarely infects human because it infects immunocompromised patients causing cutaneous, endocarditis and pneumonia infections. It is also a pathogenic plant and contaminating the crops. The effect of alcoholic extract of leaves of Achillea millefolium (yarrow), Salvia officinalis (sage) and Cassia spp.(seena), was tested by using four concentrations for each extract 5,10,15,20 mg/ml. Results were compared with the antifungal ketoconazole and with the biocontrol agents Trichoderma viride and Trichoderma harzianum. It is noticed that the highest percentage of inhibition was at concentration 20mg/ml for all the plant extracts used for inhibition percentage for A. millefolium, S. officinalis and Cassia spp.were 56.6%, 83.3% and 100% respectively. For ketoconazole the percentage of inhibition was 100% for all concentrations used in this study. The biocontrol agents T. harzianum and T. viride proved to have a high antagonistic ability against the pathogen. This proves that the alcoholic leaves extracts of these plants were more inhibitory for the fungus in addition to biocontrol agents.

Penggunaan mikroba sebagai sumber senyawa bioaktif memiliki beberapa kelebihan di antaranya mempersingkat waktu produksi dan menghindari pemanfaatan sumberdaya laut secara berlebih. Penelitian terdahulu menghasilkan beberapa isolat mikroba yang berpotensi sebagai penghasil senyawa bioaktif, di antaranya adalah isolat kapang MFW 26-08. Penelitian ini bertujuan untuk melakukan optimasi pertumbuhan isolat kapang MFW 26-08 dan produksi senyawa bioaktif yang disekresikan oleh kapang tersebut. Optimasi dilakukan dengan menggunakan 3 jenis media: Malt Extract Broth (MEB), Glucose Peptone Yeast (GPY), dan Minimal Fungal Media(MFM); serta waktu kultivasi 2, 4, 6, 8, dan 10 minggu. Hasil riset menunjukkan bahwa ekstrak kasar kapang MFW 26-08 hasil kultivasi 2 minggu dalam medium MFM, pada konsentrasi 30 µg/mL, mampu menghambat 89% pertumbuhan sel kanker payudara T47D. Sedangkan pada konsentrasi 100 µg/mL ekstrak kapang yang dikultivasi dalam medium MEB selama 6 minggu, mampu menghambat pembentukan radikal bebas sampai 56%. Hasil identifikasi berdasarkan sifat-sifat morfologi dan molekuler menggunakan 18S rRNA, ITS1, dan ITS4 menunjukkan bahwa isolat MFW 26-08 memiliki kemiripan dengan Aspergillus ustussebesar 99%

Aspergillus ustus is a mold that rarely infects humans; only 15 systemic cases have been reported. We report the first outbreak of invasive infection caused by A. ustus among hematopoietic stem cell transplant (HSCT) recipients. Six patients with infections were identified; 3 infections each occurred in both 2001 and 2003. Molecular typing by using randomly amplified polymorphic DNA (RAPD) and antifungal drug susceptibility testing were performed on clinical and environmental isolates recovered from our hospital from 1999 to 2003. The highest overall attack rate in HSCT patients was 1.6%. The overall death rate was 50%, and death occurred within 8 days after diagnostic culture collection. Clinical isolates exhibited decreased susceptibility to antifungal drugs, especially azoles. RAPD and phylogenetic analysis showed genetic similarity between isolates from different patients. Based on the clustering of cases in space and time and molecular data, common-source acquisition of this unusual drug-resistant species is possible.

Twenty four fungal species were screened for their ability to produce alkaline L-methioninase on methionine-glucose liquid medium. Aspergillus ustus AUMC 10151 displayed the highest yield of enzyme (10.8 U/mg protein), followed by A. ochraceus and Fusarium proliferatum. Upon optimization of the submerged fermentation (SmF)conditions, the maximum enzyme yield (18.23 U/mg protein) was obtained on a medium containing L-methionine (0.5%), sucrose (0.95%), KH2PO4 (0.1%) and 175 rpm. Seven agro-industrial by-products were screened as substrates for L-methioninase production under solid-state fermentation (SSF). Wheat bran resulted 38.1 U/mg protein, followed by rice bran (27.6 U/mg protein) and soya bean meal (26.6 U/mg protein). Maximum alkaline L-methioninase (99.56U/mg protein) was achieved at initial moisture content of 71.5%, inoculum size of 2.0 mL of spore suspension, initial pH 8.5, incubation period eight days at 30°C and supplementation of the salt basal medium with pyridoxine(100 μg/mL) and beet molasses (20% v/v). The productivity of L-methioninase by A. ustus under SSF was higher than that of SmF about 5.45 fold under optimum conditions.