BackgroundBeta-glucosidase inhibitors are being extensively studied for use as anti-diabetics, anti-obesity and anti-tumour compounds. So far, these compounds have been reported in large numbers from plants, mushrooms, algae and fungi. There are very few reports of such inhibitors from bacteria in the open literature, particularly marine bacteria; although the best known inhibitor deoxynojirimycin was isolated from bacilli and actinomycete. Through this study, we tried to discover the diversity of microbial associates of marine sponge and sediment producing β-glucosidase inhibitors.ResultsWe found 41 (22.7%) out of 181 bacteria, produced such inhibitors. The inhibitors are abundant in bacterial associates of marine sponge Aka coralliphaga. When these bacteria were phylogenetically analyzed, it was found that marine bacteria producing glucosidase inhibitors belong to the phylum Firmicutes (23), Actinobacteria (9), Proteobacteria (7) and Bacteroidetes (1).ConclusionA significant number of marine bacteria belonging to a wide range of bacterial taxa were found to produce β-glucosidase inhibitors. These compounds are abundantly present in bacteria of the phylum Firmicutes followed by the phylum Actinobacteria. The results nurture a hope of finding new compounds, which can inhibit glucosidases, in the bacterial domain of marine organisms. Thus, marine microbial cells can be utilized as producers of pharmacologically essential enzyme inhibitors.

BackgroundAcetylcholinesterase (AChE) inhibitors or anticholinesterases reduce the activity of enzyme acetylcholinesterase that degrades the neurotransmitter acetylcholine in the brain. The inhibitors have a significant pharmacological role in neurodegenerative diseases like Alzheimer’s and Parkinson’s etc. Although plants have been a significant source of these compounds, there are very few sporadic reports of microorganisms producing such inhibitors. Anticholinesterase activity in bacterial associates of marine soft corals and sponges were not previously reported.ResultsWe screened 887 marine bacteria for the presence of acetylcholinesterase inhibitors, in a microplate based assay, and found that 140 (15.8%) of them inhibit the electric eel enzyme, acetylcholinesterase. Majority of the active isolates were bacterial associates of soft corals followed by sediment isolates while most of the potent inhibitors belonged to the bacterial associates of marine sponges. Maximum inhibition (54%) was exhibited by a bacterial strain M18SP4P (ii), isolated from the marine sponge Fasciospongia cavernosa. Based on phenotypic characterization and 16S rDNA sequencing, the strain was identified as Bacillus subtilis - revealing yet another activity in a strain of the model organism that is considered to be a cell factory. TLC bioautography of the methanol extract of this culture, showed the presence of two major components having this activity, when compared to Galanthamine, the positive control.ConclusionFrom the results of our study, we conclude that acetylcholinesterase inhibitors are quite prevalent in marine bacteria, particularly the bacterial associates of marine invertebrates. Several potential AChE inhibitors in marine bacteria are waiting to be discovered to provide easily manipulable natural sources for the mass production of these therapeutic compounds.

BackgroundFew beta-glucosidase inhibitors have so far been reported from microorganisms due to the practical difficulties in performing the inhibition tests and subsequent interpretation of results. In an effort to investigate marine microbial extracts for β-glucosidase inhibitors, we developed a new protocol, using esculin as substrate in an agar plate based assay, to screen a large number of microbial extracts in a short span of time.ResultsWith the new method, pale yellowish zones against the blackish brown background could be visually observed with more clarity in sample extracts where β-glucosidase inhibitor was present. The new method was compared with the closest existing method and established beyond doubt. This agar plate based procedure required about one hour for minimum 12 samples and the throughput increases with the size of the agar gel plate used.ConclusionsThe new protocol was simple, rapid and effective in detecting beta-glucosidase inhibitors in microbial extracts.

The larval stage of Spodoptera litura Fab. is more prone to parasitism. Larval parasitoids such as braconids belongs to family Braconidae of order Hymenoptera acts as Ecto parasitoids. Braconids have wide host range and successful biocontrol agent recommended for the control of lepidopteran larvae in many crops and stored grains. The present study on parasitization of braconids on S. litura was conducted under laboratory conditions. The larva of S. litura collected from castor crop from various locations near by Nagpur, Maharashtra, India and reared on castor leaves under laboratory conditions. The larvae were parasitized by two parasitoids namely, Cotesia spp. and Bracon spp. The study revealed that the field collected larva of S. litura when reared on castor leaves showed an average parasitization of 11% and 4.3% by Cotesia spp. and Bracon spp. respectively.

The aim of this study was to evaluate the antifungal efficacy of Kocuria marina (BMKo1) derived Lactic acid against Epidermophyton floccosum (MTCC-613) infections induced on male Swiss Albino mice model (Mus musculus).  For this purpose, the isolated strain was subjected to ‘flask fermentation’ and the Lactic acid produced as fermentation product, was quantified and analysed. Prior to preclinical test, healthy mice models of approximately 8 weeks old and 25-30 gm (weight) were subjected to intra-dermal administration for a period of 15 days to test for toxicity. Mortality, clinical signs, body weight changes were continually monitored. Then the mouse models were inoculated with 100 µl/ml (V/V) of E. floccosum (MTCC-613) spore suspensions following ‘Excision model’. After induction of the infection, the symptomatic mice groups were subjected to topical application of Kocuria lactic acid cream based formulation at a concentration of 1µl/ml (V/V). The naked eye observations were made on the infected lesions till the absolute deduction of infection of excised skin surfaces. The degrees of deduction of infection were converted into scores and the percentages (%) of deduction of infection were calculated and the average value was derived. There were inclusion of positive control (Fluconazole) and negative control (group with infection induced excision, but without any drug application) mice groups for the sake of comparison. Further, with absolute deduction of infection score observed in mice group, applied with Kocuria derived Lactic acid was akin to Fluconazole activity. However, the infection induced mice group was found to be with substantial increase of degree of infection. This study have curtain raised about the anti Epidermophyton infection activity of a cream based  Cell free Lactic acid derived from a non pathogenic strain of Kocuria marina on mouse models. Keywords: Kocuria marina, Epidermophyton floccosum, Lactic acid