Chemical Components of Fungus Comb from Indo-Malayan Termite Macrotermes gilvus Hagen Mound and Its Bioactivity against Wood-Staining Fungi

Recently, the architectural and physical properties of the fungus comb from subterranean termite Macrotermes gilvus Hagen (Isoptera: Termitidae) mounds had been studied and it is important to determine its chemical profile as well as to evaluate its anti-staining-fungi activity. The results showed that fungus comb of M. gilvus has a high crude ash (30.57%), fiber (25.46%), starch (7.76%), protein (5.80%, 5.53% amino acid), acid-insoluble ash (3.45%), and fat (0.73%). It also contained phenol hydroquinone, steroids, terpenoids, and saponin compounds. Seventeen amino acids were identified via high-performance liquid chromatography analysis, of which arginine, leucine, glutamate, and aspartic acid were the majority. According to gas chromatography-mass spectrometry analysis, the n-hexane extract consists of several types of fatty acid derivatives. Meanwhile, the ethyl acetate (EtOAc) extracts were primarily phenol groups with 1,2,3-propanetriol (glycerol) at the highest relative concentration. Four fungus-comb extracts (n-hexane, EtOAc, MeOH, and water) inhibited the Aspergillus foetidus fungus, with inhibition rates ranging from 24.17% to 100% and EtOAc extract as the most active extract. It appears that EtOAc extracts from the M. gilvus fungus comb can be considered an active ingredient source of novel organic fungicide in preventing wood-staining fungi attacks on susceptible wood.

Molecular Characterization of a Novel Alternavirus Infecting the Entomopathogenic Fungus Cordyceps Chanhua

In this study, a novel double-stranded RNA (dsRNA) mycovirus, named Cordyceps chanhua alternavirus 1 (CcAV1), was detected in the entomogenous fungus Cordyceps chanhua from China. The complete genome of CcAV1 contained three dsRNA genome segments, dsRNA 1 (3,512 bp), dsRNA 2 (2,655 bp), and dsRNA 3 (2,415 bp). All the three dsRNAs possess a single open reading frame (ORF). DsRNA 1 with 3,512 bp long encoded a putative RNA-dependent RNA polymerase (RdRp), while dsRNA 2 with 2,655 bp long and dsRNA 3 with 2,415 bp long encoded a hypothetical protein 1 (HP 1) and a hypothetical protein 2 (HP 2), respectively. The RdRp, HP 1 and HP 2 sequences had the highest identity of 66.99%, 49.30% and 56.91%, respectively, to those of Aspergillus foetidus dsRNA mycovirus. A maximum-likelihood phylogenetic tree from RdRp sequence revealed that CcAV1 was placed in the clade of the proposed family “Alternaviridae”. Hence, we proposed that Cordyceps chanhua alternavirus 1 is a novel member of the proposed “Alternaviridae”.

Aspergillus foetidus Regulated the Biochemical Characteristics of Soybean and Sunflower under Heat Stress Condition: Role in Sustainability

Plants are susceptible to various environmental constrains, including heat stress due to their sessile nature. Endophytic fungi can be used as a novel technique to protect crop plants against the injurious effects of thermal stress. Endophytic fungi were isolated from Adiantum capillus-veneris L. and tested against heat stress in Glycine max L. and Helianthus annuus L. The results exhibited increased levels of the plant’s chlorophyll, height and biomass in Aspergillus foetidus (AdR-13) inoculated host crop species. Conversely, a significant decrease in lipid peroxidation and reactive oxygen species (ROS) production was noted in A. foetidus-associated host crop species. Likewise, the amounts of ROS-degrading antioxidants (glutathione reductase (GR), peroxidase (POD), ascorbic acid oxidase (AAO), superoxide dismutase (SOD), catalase (CAT)) as well as phenolics were increased, while the amounts of proline and abscisic acid (ABA) were decreased in fungal-associated test crops. Total lipids, proteins and sugars were noted to be high in A. foetidus-associated test crops. From the results, we concluded that A. foetidus have a role in heat stress mitigation that might help to sustain the production of important crops in the future.

DEGRADAÇÃO DA MATÉRIA ORGÂNICA PRESENTE NA ÁGUA RESIDUÁRIA DO CAFÉ UTILIZANDO MICRORGANISMOS

O café representa um setor economicamente importante sendo uma das principais commodities nacionais, uma vez que o Brasil é mundialmente, o maior produtor e exportador de café. Durante o processamento via úmida se utiliza água com a finalidade de facilitar o processamento e retirar a mucilagem para evitar a fermentação dos grãos gerando uma água residuária com alta teor de matérias orgânicas. Assim, o tratamento adequado da água residuária do café torna-se necessário, uma vez que se lançada ao meio ambiente sem tratamento pode causar sérios impactos. Dessa forma, o objetivo deste estudo foi avaliar a utilização de fungos filamentosos na degradação da matéria orgânica presente na água residuária do processamento úmido do café. A água residuária do processamento úmido do café (Coffea arábica L.) utilizada no experimento foi obtida em uma propriedade rural localizada no município Campestre, Minas Gerais e os isolados utilizados foram CCDCA 10495 (Aspergillus foetidus); A.niger 00194 (Aspergillus niger); CCDCA 10232 (Aspergillus niger) e CCDCA 11402 (Penicillium biliae). Os isolados A. niger 00194 (Aspergillus niger) e CCDCA 10495 (Aspergillus foetidus) foram os que microrganismos que degradaram, com mais eficiência, a matéria orgânica presente na água residuária do café após 196 horas de fermentação.

Selection of stain fungi on rubberwood (Hevea brasiliensis) and its growth response against chitosan

Salman ABA, Sudirman LI, Nandika D. 2020. Selection of stain fungi on rubberwood (Hevea brasiliensis) and its growth response against chitosan. Biodiversitas 21: 4501-4508. Rubberwood (Hevea brasiliensis Muell. Arg.) is one of the most important raw materials in furniture industry in South East Asian countries, particularly in Indonesia, Thailand and Malaysia. However, due to its susceptibility to stain fungi attack, wood preservative is needed to processing this material, which has both significant cost and environmental implications. A laboratory study was conducted to identify the seasoned rubberwood attacking stain fungi and to evaluate the bioactivity of chitosan in inhibiting the stain fungi’s growth. Isolation fungi from seasoned rubberwood were obtained firstly then selection isolates were conducted in the rubberwood test samples. Isolates with the highest percentage growth on wood test samples would identify based on internal transcribed spacer (ITS) region. Chitosan were prepared in four concentration 0, 0.5, 1 and 2% (w/v). Two isolates were showed the highest percentage growth on wood test samples after six weeks, which were 90.6% for isolate code I4 and 96.2% for II4 and both isolates gained scores 5. The two isolates were identified as Aspergillus foetidus for I4 and Aspergillus aflatoxiformans for II4. Aspergillus foetidus and A. aflatoxiformans would be the newly recorded species and this is the first report about species description from rubberwood in Indonesia. The inhibition rate was increased when chitosan concentration was increased from 0 to 2%. Chitosan concentration 2% inhibited the growth of A. foetidus in 20.28%, but there is no inhibition showed on A. aflatoxiformans. The addition of chitosan in medium can increase the growth of A. aflatoxiformans and forming clear zone around the colony.

Using Lignosellulose Waste as a Xylanase Production Media of Mold Isolated from Rice Straw of Coastal-field

Hemicellulose is one of lignocellulose waste component, so that xylanase is one of importance enzyme of lignocellulose waste biodegradation. Molds as main decomposer lignosellulose waste has enzyme activities higher than yeast and bacteria. The aim of the research is to find mold that have xylanolitic activity using lignocellulose waste as media production. The research consist of isolations and screening mols from coastal-field of watu Ulo Jember, xylanase production using lignocellulose waste and idntification of mold which has the highes xylanase activity. A total of 66 molds isolated from rice straw in coastal-field of Watu Ulo Jember. There were screened for their xylanase activity. In semiquantitatively screen on Oat Spelt Xylan plate, the result showed that 62 have xilanolytic activities. Based on clearing zone production, isolates ESW A1 (3.2), ESW A5 (3.1), ESW C 16 (3.26), ESW D4 (3.0) and ESW D15 (3.21) have xilanase activity index higher than others. Furthermore, quantitative analysis using wheat bran, rice straw and baggase in basic salt Mandel’s modification media showed that xylanase activity of isolate ESW D4 was higher on rice straw 3% as substrate production with activity 2.66 U/mL. Isolate ESW D4 identified as Aspergillus foetidus so that called as Aspergillus foetidus ESW D4. Keywords: rice straw, coastal-field, Aspergillus foetidus ESW-D