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Fungi associated with cypress bark beetles are practically unknown in the Eastern Mediterranean. Our study focused on the fungi associated with the body parts and galleries of two indigenous cypress bark beetles, Phloeosinus armatus and P. bicolor, sampled from Cupressus sempervirens trees in different regions in Israel. Arbitrarily primed PCR, performed on genomic DNA of 302 isolates, clustered the fungal population into five distinct groups. Multilocus phylogeny, split-network analyses and morphological characterization identified the isolates as Geosmithia omnicola, Geosmithia langdonii, Geosmithia sp. 708b, Geosmithia cupressina sp. nov. CBS147103 and Talaromyces cupressi sp. nov. CBS147104. Of these fungal isolates, G. cupressina and T. cupressi are newly described, and their morphological features and phylogenetic designations are presented. Inoculation of intact cypress saplings in an outdoor net-house revealed that only the representative isolate T. cupressi sp. nov. CBS147104 causes 100% disease incidence, whereas Geosmithia spp. isolates are not pathogenic. A number of these fungi were isolated from parasitoids that emerged from branch and stem sections colonized by P. armatus. This study suggests a long and stable association between Phloeosinus and Geosmithia species, and a possible role for additional associated fungal species as pathogens or endophytes of C. sempervirens trees in Israel.

Mycoherbicides are exclusive biotechnology products which offer a non-chemical solution to control noxious weeds on the land as well as aquatic in systems, viz a viz saving environment from hazardous impact of synthetic chemicals. The present paper highlights the mycobiota associated with Eichhornia crassipes infesting Harike wetland area of Punjab and evaluation of their pathogenic potential for futuristic application as a mycoherbicide. Of the 20 isolates tested by leaf detached assay and whole plant bioassays, only one isolate (#8 BJSSL) caused 100% damage to E. crassipes. Further, the culture filtrate of this isolate also exhibited a similar damage to the leaves in an in vitro detached leaf assay. The potential isolate was identified as Phaeoacremonium italicum using classical and modern molecular methods. This is the first report of P. italicum as a pathogen of E. crassipes and of its potential use as a biological control agent for the management of water hyacinth.

Xylarinase is a bi-functional fibrinolytic metalloprotease isolated from the culture filtrate of endophytic fungus Xylaria curta which is monomeric with a molecular mass of ∼33.76 kDa. The enzyme displayed both plasmin and tissue plasminogen activator like activity under in vitro conditions. It hydrolyses Aα and Bβ chains of the fibrinogen. Optimal fibrinolytic activity of xylarinase is observed at 35 °C, pH 8. Ca2+ stimulated the fibrinolytic activity of xylarinase while Fe2+ and Zn2+ inhibited suggesting it to be a metalloprotease. The Km and Vmax values of xylarinase were 240.9 μM and 1.10 U/ml for fibrinogen and 246 μM and 1.22 U/ml for fibrin, respectively. Xylarinase was found to prolong the activated partial thromboplastin time and prothrombin time. The N-terminal sequence of xylarinase (SNGPLPGGVVWAG) did not show any homology with previously known fibrinolytic enzymes. Thus xylarinase is a novel fibrinolytic metalloprotease which could be possibly used as a new clot busting enzyme.

With increasing human population and limited land for agriculture, it has become a herculean task to provide food security to over 7 billion people around the world. The majority of the food produced is lost in postharvest losses. The present approaches to manage the current situation appear to be ineffective and unsustainable. Further, the development of resistance in microbes against the current arsenal of drugs and the destructive effects of methyl bromide and sulfur dioxide on the ozone layer has worsened the situation. This calls for an urgent need to explore alternate avenues for management of postharvest losses. Besides various chemical approaches, exploration of natural resources for finding out new anti-infective and biocontrol agents appears to be a plausible and sustainable solution for management of postharvest losses. Muscodor is a genus of sterile endophytic fungi which has the remarkable property to produce a mixture of volatile organic compounds (VOCs) which are lethal against a number of plant and human pathogenic bacteria and fungi, nematodes, and moths. Further, the VOCs of Muscodor spp. have also shown promising application as biocontrol agent and in management of human waste. Recently, the extrolites of Muscodor species have also shown promising antimicrobial, anti-obesity, antihyperuricemic, and antioxidant activity. Hence, the current chapter embodies the potential uses of volatiles and other extrolites produced by Muscodor species and their possible application in agriculture and pharmaceutical industries.

Ever since the landmark discovery of paclitaxel from endophytic Taxomyces andreanae, plant endophytes have been the fountainheads of bioactive secondary metabolites with potential application in medicine, agriculture, and food industry. In the last two decades, lead molecules with antimicrobial, anticancer, antioxidant, and anti-inflammatory properties have been successfully discovered from endophytic microorganisms. Bioprospecting endophytes for enzyme inhibitors has been an important facet of endophytic research. Several enzyme inhibitors like altenusin, huperzine, camptothecin, and podophyllotoxin have been successfully isolated from endophytic microorganisms. The current chapter partially embodies the research progress on endophytic microorganisms for producing bioactive enzyme inhibitors and their possible use in pharmaceutical industries.

Genus Muscodor came into existence with the discovery of Muscodor albus, a sterile endophytic fungus that produces a medley of volatile organic moieties possessing strong antimicrobial activity. The current paper reports Muscodor tigerii as a novel endophytic fungus from the stem internal tissue of Cinnamomum camphora growing in the Tiger Hill area of Darjeeling, West Bengal, India. M. tigerii exhibited distinct morphological, molecular and physiological features than previously reported Muscodor species. The fungus possesses all the morphological features described till date in genus Muscodor making it remarkably unique. The strong fruity smell of the fungus is attributed to 22 volatile organic compounds (VOCs), predominantly 4-Octadecylmorpholine, 1-Tetradecanamine,N,N-dimethyl and 1,2-Benzenedicarboxylic acid, mono(2-ethylhexyl) ester. The in vitro VOC stress assay completely suppressed the growth of Alternaria alternata and Cercospora beticola while growth of other fungal species was inhibited in a range of 10 %-70 %. The growth of Candida albicans in the presence of VOC was reduced by 50 %-65 % while in bacteria 50 %-80 % reduction in growth was observed. Thus, M. tigerii stands as a potential candidate to be further developed into a biocontrol agent.

Muscodor kashayum (MycoBank no.: MB 803800; GenBank no.: KC481680) is a newly described endophytic fungus of a medicinal plant Aegle marmelos (Bael tree), growing in the tropical conserved rainforest in the Western Ghats of India. Muscodor kashayum possesses distinct morphological, molecular and physiological features from the earlier reported Muscodor species. The fungus forms characteristic rings of the ropy mycelium on potato dextrose agar medium. This sterile fungus is characterised by the presence of a pungent smell which is attributable to a blend of more than 23 volatile organic constituents, predominantly 3-cyclohexen-1-ol,1-(1,5-dimethyl-4-hexenyl)-4-methyl; 1,6-dioxacyclododecane-7,12-dione; 2,6-bis(1,1-dimethylethyl)-4-(1-oxopropyl) phenol; 2,4-di-tert-butylthiophenol and 4-octadecylmorpholine. In the in vitro anti-microbial assay using M. kashayum, growth of 75% of test fungi/yeasts and 72% of the test bacteria were completely inhibited. Therefore, M. Kashayum holds potential for future application to be used as a myco-fumigation agent.

The present investigation highlights the optimal conditions for production of a non-toxic, bi-functional fibrinolytic enzyme xylarinase produced by endophytic fungus Xylaria curta by solid substrate fermentation using rice chaff medium. The purified enzyme is a monomeric protein with a molecular mass of ∼33 kDa. The enzyme exhibits cleavage of Aα and Bβ chains of fibrin(ogen) and has no effect on γ chain. The optimal fibrinolytic activity of the enzyme was observed at 35 °C and pH 8. The fibrinolytic activity was enhanced in the presence of Ca2+, whereas it was completely inhibited in the presence of Fe2+ and Zn2+ ions and inhibitors like EDTA and EGTA suggesting it to be a metalloprotease. The K m and V max of the enzyme for azocasein were 326 μM and 0.13 μM min−1. The N-terminal sequence of the enzyme (SNGPLPGGVVWAG) was same when compared to xylarinase isolated from culture broth of X. curta. Thus, xylarinase could be exploited as a potent clot busting enzyme which could be produced on large scale using solid substrate fermentation.

Infections caused by Staphylococcus aureus are ubiquitous and life threatening. Evolution of resistant strains has necessitated the need to continuously discover new drugs to combat such organisms. Diphenyl ethers, such as triclosan, have recently shown potential as antibacterial agents. In this study, a series of diphenyl amines were synthesized and evaluated for in vitro antibacterial activity against Gram-positive (Staphylococcus aureus, Bacillus subtilis, Staphylococcus epidermidis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Pseudomonas putida) bacteria. Preliminary results showed that six of the twelve synthesized molecules were active against Staphylococcus aureus. Most notable amongst them were compounds 2(2,4-dinitrophenylamino)phenol and 2(2-dinitrophenylamino)phenol having minimum inhibitory concentration (MIC) in the range of 7.8-15.6 µg mL-1 and 7.8-62.5 µg mL-1respectively for all the eight selected organisms. Five active compounds from the preliminary results were further screened against resistant S. aureus cultures where compounds 2(2,4-dinitrophenylamino)phenol, 2(2-dinitrophenylamino)phenol and 2-chloro-N-(2-(2,4-dichlorophenylamino)phenyl)acetamide gave encouraging results having MIC in the range 3.9-7.8 µg mL-1for most of the organisms. Results obtained above for the selected organisms and the resistant S. aureus strains conclude that hydroxyl group at 2-position of ring B potentiates the antibacterial activity and overcomes the antibiotic resistance.

Objective: This communication explores a lead fraction from methanolic extract of novel Stevia species raised under in vitro conditions for its various biological activities. Methods: The dried Stevia leaves were crushed in methanol to get the polar extract. This methanol extract was tested for pancreatic lipase and alpha-amylase inhibitory activity using quantitative plate assays. Antibacterial property of the extract was also evaluated against Staphylococcus epidermidis , Escherichia coli , Bacillus subtilis, Staphylococcus aureus, and Pseudomonas aeruginosa. Further, the antioxidant potential was evaluated using 1,1-diphenyl-2-picrylhydrazyl. Results: The methanolic extract inhibited pancreatic lipase with IC50 of 5.74 μg/ml in a similar manner to a well-known anti-obesity drug in the market orlistat. The methanolic extract also showed a better pancreatic α-amylase inhibitory activity (IC50=88 μg/ml) than acarbose. Further, the lead fraction exhibited 88.48% antioxidant activity. It also exhibited broad spectrum antimicrobial activity against the spectrum of Gram-positive and Gram-negative bacteria tested under laboratory conditions with a minimal inhibitory concentration ranging from 1.95 to 31.25 μg/ml. Conclusion: Thus, this study signifies the vast potential of the lead fraction from a novel Stevia species for further development into a herbal formulation for prevention of various infectious and non-infectious diseases.

Cost-effective, fibrinolytic agents possessing least or no antigenic properties are much in demand for their prospective use as clot busters in thrombolytic therapy. The present communication explores the potential of 22 endophytic Botryosphaeria species isolated from stem of Aegle marmelos for their fibrinolytic potential. Only nine fungal isolates exhibited proteolytic activity out of which only four possessed plasminogen-independent fibrinolytic activity. The endophytic fungal isolate #1088 AMSTITYEL showed maximum in vitro proteolytic and fibrinolytic activity with a halo formation of 153.86 and 113.04 mm2, respectively. The partially purified protein exhibited a fibrinolytic activity equivalent to 6.51 U/ml of plasmin. SDS–PAGE of the dialysed fraction of #1088 AMSTITYEL resolved into six bands ranging from 26 to 80 kDa. Fibrin zymogram exhibited that a single band of molecular size ~80 KDa possessing the fibrinolytic activity. Furthermore, the bioactive isolate #1088 AMSTITYEL was identified as Lasiodiplodia pseudotheobromae using classical and molecular taxonomic tools. Electronic supplementary material The online version of this article (doi:10.1007/s13205-016-0428-4) contains supplementary material, which is available to authorized users.