Fungal exopolysaccharides (EPSs) have been recognized as high value biomacromolecules for the last two decades. These products, including pullulan, scleroglucan, and botryosphaeran, have several applications in industries, pharmaceuticals, medicine, foods etc. Although fungal EPSs are highly relevant, to date information concerning fungal biosynthesis is scarce and an extensive search for new fugal species that can produce novel EPSs is still needed. In most cases, the molecular weight variations and sugar compositions of fungal EPSs are dependent to culture medium composition and different physical conditions provided during fermentation. An inclusive and illustrative review on fungal EPS is presented here. The general outline of the present work includes fungal EPS production, their compositions and applications. An emphasis is also given to listing out different fungal strains that can produce EPSs.

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A tannase-producing soil bacteria has been isolated and identified as Bacillus cereus. It can degrade tannic acid and produce maximum tannase (0.22 U/ml) at stationary phases of growth (24 h). Maximum growth and enzyme production occurred with initial medium pH of 4.5-5.0. Partial purified tannase showed optimum activity at pH 4.5 and 40°C. It remains stable up to 30°C and pH 4.5 to 5.0. The enzyme is salt tolerant, stable up to 2 M of NaCl and retains 82% original activity in 3 M.

Pueraria tuberosa (Willd.) DC is a perennial herb commonly known as 'vidarikanda', distributed throughout south east Asia. The plant's tuber is widely used in ethanomedicine as well as in traditional systems of medicine, particularly in ayurveda. It has been used in various ayurvedic formulations as restorative tonic, antiaging, spermatogenic and immune booster and has been recommended for the treatment of cardiovascular diseases, hepatosplenomegaly, fertility disorders, menopausal syndrome, sexual debility and spermatorrhoea. Numerous bioactive phytochemicals, mostly isoflavonoids such as puerarin, genistein, daidzein, tuberosin and so on have been identified in the tuber. In vivo and in vitro studies have provided the support against traditional demands of the tuber as spermatogenic, immune booster, aphrodisiac, anti-inflammatory, cardiotonic and brain tonic. However, further studies are required to define the active phytochemical compositions and to validate its clinical utilisation in the herbal formulations for human uses. This review provides an overview of traditional applications, current knowledge on the phytochemistry, pharmacology and toxicology of P. tuberosa. This review also provides plausible hypotheses about how various isoflavones particularly puerarin, genistein and daidzein, individually or collectively, may be responsible for the therapeutic potential against a wide range of ailments.

A comparative study on the simultaneous production of extra and intracellular tannase was made from newly isolated fungal strain Aspergillus aculeatus DBF 9. This strain produced five times more intracellular enzyme within 24 h in liquid culture than the extracellular form. Maximum tannase production occurred in the culture broth containing 1–2% (w/v) tannic acid and 0.05–0.1% (w/v) glucose. The pH and temperature optima of both the enzymes were found at 5.0 and 50–60 °C, respectively. Extra and intracellular tannase showed good stability at higher temperature, pH values and salt (NaCl) concentration. These properties make the enzyme suitable for pollution control and bioprocess industry.

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Seeking solutions from nature for solving one and all problems is the age-old practice for mankind, and natural products are proved to be the most effective one for keeping up the balance of development as well as the "healthy, wealthy, and well" condition of mother nature. Fungal pathogens are proved to be a common and popular contaminant of agroecosystem that approximately causes 70-80% of total microbial crop loss. To meet the proper global increasing need of food products as a result of population explosion, managing agricultural system in an eco-friendly and profitable manner is the prime target; thus the word "sustainable agriculture" plays it part, and this package is highly effective when coupled with nature-derived fungicidal products that can minimize the event of fungal infections in agrarian ecosystem. Present study enlists the most common and effective natural products that might be of plant or microbial origin, their mode of action, day-by-day development of phytopathogenic resistance against the prevailing fungicides, and also their role in maintenance of sustainability of agricultural practices with special emphasis on their acceptance over the synthetic or chemical one. A large number of bioactive compounds ranging from direct plant (both cryptogams algae and moss and phanerogams)-derived natural extracts, essential oil of aromatic plants, and low-molecular-weight antimicrobial compounds known as phytoalexins to secondary metabolites that are both volatile and nonvolatile organic compounds of microbes (fungal and actinobacterial members) residing inside the host tissue, called endophyte, are widely used as agricultural bioweapons. The rhizospheric partners of plant, mycorrhizae, are also a prime agent of this chemical warfare and protect their green partners from fungal invaders and emphasize the concept of "sustainable agriculture." 132

BackgroundCorneal diseases are one of the major causes of visual loss and blindness, second only to cataract. Amongst corneal diseases, microbial keratitis is a major blinding disease. In some countries, fungal keratitis accounts for almost 50% of patients with culture-proven microbial keratitis.AimThis study was conducted to determine the epidemiological characteristics of fungal keratitis in an urban population of West Bengal and identify the specific pathogenic organisms.MethodsThe charts of patients with microbial keratitis who attended the Cornea Services of Priyamvada Birla Aravind Eye Hospital from January to December 2008 were retrospectively reviewed. Records of patients with 10% KOH mount and culture positive fungal keratitis were analyzed for epidemiological features, laboratory findings and treatment outcomes.ResultsOf the 289 patients of microbial keratitis included in the study, 110 patients (38.06%) were diagnosed with fungal keratitis (10% KOH mount positive). Of the 110 patients, 74 (67.27%) fitted the study inclusion criteria (10% KOH mount and culture positive). Forty five of 74 patients (60.81%) in the study group were in the older age group (>50 years). Ocular trauma in 35 cases (47.29%) was identified as a high risk factor and vegetative injuries in 17 cases (22.97%) were identified as a significant cause for fungal keratitis. Maximum organism source was from corneal scrapings in 41 cases (55%). The predominant fungal species isolated was Aspergillus sp (55.40%) followed by Candida albicans 14 cases (18.91%) and Fusarium sp. in 8 cases (10.81%). Agricultural activity related ocular trauma was the principal cause of mycotic keratitis and males were more commonly affected. Thirty of 74 cases (40.55%) of the culture positive patients healed with corneal scar formation with medical treatment whereas 44 cases (59.45%) required therapeutic keratoplasty.ConclusionFungal keratitis is an important cause of microbial keratitis with injury to the cornea being a leading predisposing factor. Although Aspergillus sp. was implicated in most of the patients in our study population, Candida sp. were found in higher numbers than previously reported. Keratitis caused by filamentous fungi responds adequately to medical management. Therapeutic keratoplasty continues to remain an important treatment modality in infections with Candida sp. Early diagnosis with prompt identification of the pathogenic organism is mandatory to initiate appropriate therapy and thereby reduce morbidity.