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2,3-Butanediol (2,3-BDO) has varied applications in chemical, pharmaceutical, & food industry. Microorganisms belonging to Klebsiella, Enterobacter & Serratia genera are well-known producers of 2,3-BDO. However, they have limited usage in industrial-scale owing to their pathogenic nature. A nonpathogenic soil isolate identified as Bacillus licheniformis (BL1) was thus investigated for 2,3-BDO production. Soy flakes, soy flour, defatted soy, and soybean meal-based hydrolysates replaced yeast extract and peptone as nitrogen sources. Defatted soy flakes and soybean meal hydrolysate led to an equivalent 2,3-BDO yield and productivity as compared to that of Yeast Extract and peptone. The pH and oxygen variation influenced the proportion of various products of the mixed acid-butanediol pathway. Further, the batch mode fermentation with soy hydrolysate and optimized process parameter resulted in 2,3-BDO titer, yield and productivity of 11.06 g/L, 0.43 g/g and 0.48 g/L h respectively. Glucose concentration above 5% was inhibitory and led to reduction in the specific growth rate of BL1 in batch cultivation. Intermittent glucose feeding in fed-batch mode overcame this substrate limitation resulting in increased titers (49.8 g/L) and productivity (0.62 g/L h). Modified medium containing soy hydrolysate as nitrogen source with fermentation process optimization resulted in 67% decrease in medium cost for 2,3-BDO production.

Thraustochytrids are the most prominent source of polyunsaturated fatty acids, specifically docosahexaenoic acid (DHA). Downstream processing constitutes a significant fraction of total production cost and thus needs judicious optimization. Currently, hazardous solvent-based extraction methods are used to extract oil from the dry or wet thraustochytrids cell mass. The process is also highly energy-intensive due to involvement of dewatering and drying as unit operations. Current work devised an energy-efficient acid-assisted extraction (AAE) methodology to overcome dry and wet biomass-based extraction limitations. AAE recovered 91 % of total oil with 35-40 % PUFA from the direct fermentation broth, eliminating the need for dewatering and drying of fermentation broth/cell biomass. The current work also presents an all-inclusive comparison of the energy assessment of oil extraction from dry and AAE method. AAE produced PUFA enriched oil with a total energy consumption of 210 MJ/kg, which was four times lower than that of conventional dry cell extraction methodology.

The efficiency of light utilisation through photosynthesis is the most critical factor for microalgal growth. Microalgae face photo-damage at higher light irradiance due to over absorption of light energy. Photosynthesis becomes light-saturated with the increase in light intensity, primarily due to larger antenna size. The strain improvement with reduced antenna size is thus desirable for the optimum conversion of sunlight to algal biomass. The present work describes the generation of reduced chlorophyll antenna mutants of Chlorella saccharophila by EMS mutagenesis. A high light–acclimated mutant exhibited a 21% reduction in total chlorophyll fluorescence, 37% and 15% reduction in PSII and PSI antenna size respectively, with increased biomass productivity and non-photochemical quenching. All these improved photosynthetic parameters led to a 27% increase in biomass productivity under ≥ 1200 μmol photons m−2 s−1 light irradiance. The high light tolerance and biomass productivity establish the Chlorella saccharophila as promising algal species to be grown at large scale for biofuels.

Valorisation of organic wastes to produce industrially relevant commodity products is a sustainable, cost-effective and viable alternative providing a green platform for chemical production while simultaneously leading to waste disposal management. In the present study, organic wastes such as agricultural residue-derived sugars, oilseed meals, poultry waste and molasses were used for substituting expensive organic fermentation medium components. Moorella thermoacetica and Aurantiochytrium limacinum were adapted on these waste-derived hydrolysates to produce high volume-low value products such as bio-acetic acid (80% theoretical yields) and oil-rich fish/animal feed (more than 85% dry cell weight as compared with conventional nutrient sources) respectively. Use of these waste-derived nutrients led to ~ 75% and ~ 90% reduction in media cost for acetic acid and oil-rich biomass production respectively as compared with that of traditionally used high-priced medium components. The strategy will assist in the cost reduction for high volume-low value products while also ensuring waste recovery.

Paramylon from Euglena gracilis is an insoluble crystalline β-1,3-glucan which have pharmaceutical and nutraceuticals applications. The present study aims to check the prebiotic potential of paramylon derived from heterotrophically grown E. gracilis in bioreactor. The Paramylon was extracted using sodium dodecyl sulfate from E. gracilis biomass. The Fourier Transform-Infra Red spectroscopy and scanning electron microscopy demonstrated the isolated paramylon to be equivalent to that of analytical standard. The prebiotic activity of E. gracilis cell extract and isolated paramylon was studied. E. gracilis cell extract as well as isolated paramylon led to cell number enhancement of Lacfid (Lactobacillus) strain exhibiting the prebiotic activities., Euglena, Paramylon, Prebiotic, Soluble.

2,3-Butanediol (2,3-BDO) has varied applications in chemical, pharmaceutical,food industry. Microorganisms belonging to

A marine organism, belonging to the Thraustochytrids family was isolated from mangroves of Mumbai, India. The isolated strain was identified as Aurantiochytrium limacinum by internal transcribed spacer sequence analysis. Optimization of process parameters yielded 14.47 g/L dry cell weight containing 55–58% oil in 3.5 days’ cultivation on glucose, yeast extract, and peptone in the bioreactor. Docosahexaenoic acid (DHA) was found to be the dominant long-chain polyunsaturated fatty acid, accounting for 32–35% of total fatty acid content. The process parameter was tweaked to simultaneously synthesize astaxanthin along with DHA. The concurrent synthesis of DHA and astaxanthin-containing biomass establishes the isolated strain as a perfect choice for aquafeed. Accession number: NCBI accession number MN046792.

Docosahexaenoic acid (DHA) rich oil or biomass is currently being produced by fermentation of thraustochytrids by repeated fed-batch. Continuous cultivation has not been successful for DHA production because of excess carbon and limited nitrogen conditions requirement. The present study describes an alternative integrative fermentation strategy to simultaneously produce high cell density, lipids and DHA in continuous mode for Aurantiochytrium limacinum. The high cell density system (≥120 g/L DCW basis) on carbon feeding led to DHA productivity of 0.508 g/L.h on poultry waste based medium with a process time of 48–54 h. The strategy integrates the advantages of repeated fed-batch for high cell densities and DHA content in continuous cultivation.

Marine protist Aurantiochytrium limacinum produces docosahexaenoic acid (DHA) as main polyunsaturated fatty acid (PUFA) and lacks any monounsaturated fatty acids (MUFA), while eicosapentaenoic acid (EPA) and MUFA's are produced by Phaeodactylum tricornutum. The marine diatom P. tricornutum was co-cultured with A.limacinum to match the EPA:DHA ratio of fish oil. Modulation in initial cell density ratio overcame the dominance of A.limacinum during co-cultivation and led to regulated proliferation of both species. Media engineering with nitrate and glycerol concentration yielded 2:1 (56.44: 30.11) mg g

Propionic acid production from glucose was studied using Propionibacterium freudenreichii shermanii. Conditions were optimized for high yields of propionic acid and total organic acids by sequential optimization of parameters like pH, inoculum age, inoculum volume and substrate concentration. Near-theoretical yield (0.54 ± 0.023 g/g) was achieved for propionic acid with fermentation of 1% glucose using 20% (v/v) of 48 hr old P. shermanii at 30°C, pH maintained at 5.5. Total organic acid yield under these conditions was 0.74 ± 0.06 g/g. The study resulted in achieving 98% and 95% theoretical yields of propionic acid and total organic acids, respectively. Under optimized conditions, along with organic acids, P. shermanii also produced vitamin B12 and trehalose intracellularly, showing its potential to be used as a cell factory.

Valorisation of organic wastes to produce industrially relevant commodity products is a sustainable, cost-effective and viable alternative providing a green platform for chemical production while simultaneously leading to waste disposal management. In the present study, organic wastes such as agricultural residue-derived sugars, oilseed meals, poultry waste and molasses were used for substituting expensive organic fermentation medium components. Moorella thermoacetica and Aurantiochytrium limacinum were adapted on these waste-derived hydrolysates to produce high volume-low value products such as bio-acetic acid (80% theoretical yields) and oil-rich fish/animal feed (more than 85% dry cell weight as compared with conventional nutrient sources) respectively. Use of these waste-derived nutrients led to ~ 75% and ~ 90% reduction in media cost for acetic acid and oil-rich biomass production respectively as compared with that of traditionally used high-priced medium components. The strategy will assist in the cost reduction for high volume-low value products while also ensuring waste recovery.

The metabolic engineering of Chlamydomonas reinhardtii, one of the fastest-growing microalgae, is a potential alternative for enhanced carotenoid productivity. CrtYB (phytoene-β-carotene synthase - PBS) gene from red yeast Xanthophyllomyces dendrorhous encodes for a bifunctional enzyme that harbours both phytoene synthase (psy) and lycopene cyclization (lcyb) activities. Heterologous expression of this bifunctional PBS gene led to 38% enhancement in β-carotene along with 60% increase in the lutein yields under low light conditions of 75 μmol photons m-2 s-1. Short Duration-High Light induction strategy led to overall 72% and 83% increase in β-carotene and lutein yield reaching up to 22.8 mg g-1 and 8.9 mg g-1, respectively. This is the first report of expression of heterologous bifunctional PBS gene resulting in simultaneous enhancement in β-carotene and lutein content in phototrophic engineered cells. Graphical Abstract.

Thraustochytrids have predominantly been grown on hydrophilic substrates i.e. by “de novo” fermentation. The fatty acid composition of thraustochytrids oil in “de novo” mode is enriched in saturated palmitic acid and polyunsaturated docosahexaenoic acid. The “ex novo” fermentation of a novel Aurantiochytrium limacinum ICTSG-17 with waste acid oil altered the fatty acid composition of produced oil. This led to increased total unsaturated fatty acids (TUFA) and concomitant decrease in the total saturated fatty acids (TSFA) resulting in higher TUFA/TSFA ratio. However, cell growth and DHA content in “ex novo” were lower than that of “de novo” fermentation. Integration of “de novo” and “ex novo” fermentation modes were devised to attain high biomass and lipids enriched in DHA. Sequential “de novo”-“ex novo” fermentation resulted in ~20 g/L biomass and ~40% DHA content and higher TUFA/TSFA ratio as compared to that of “de novo” mode.

Parachlorella kessleri is a promising oil-bearing marine alga which shows decreased growth under high light stress. Osmolytes are known to relieve stress by protecting the cell membrane, proteins, and enzymes. Enhanced production of osmolyte (trehalose) was thus used to relieve stress in P. kessleri by overexpression of trehalose phosphate synthase (TPS) gene. Transformed P. kessleri was grown under different light regimes to study the effect of trehalose overproduction on growth. Study of one of the TPS transformants showed increased trehalose as well as increased biomass and decreased pigments, reactive oxygen species, and lipid peroxidation of cell membrane. The improved photosynthetic performance of the transformant was also signified by pulse-amplitude-modulated fluorometric analysis. All of these factors reveal improved stress tolerance under high light conditions by increased trehalose accumulation due to TPS overexpression in P. kessleri.

Sedoheptulose 1,7-bisphosphatase (SBPase), a nuclear-encoded chloroplastic enzyme, is an important rate-limiting enzyme of the carbon fixation cycle (Calvin cycle). SBPase is unique to only photosynthetic organisms and is involved in the regeneration of ribulose-1,5-bisphosphate. SBPases from several sources have been studied for their induction and regulation. However, SBPase from Chlamydomonas reinhardtii CC-503, the widely studied model microalga, has not been isolated and functionally confirmed to date. In this study, the full-length cDNA for SBPase was isolated from C. reinhardtii CC-503 using anchored oligo(dT)24VGN primer for reverse transcription. The SBPase cDNA was cloned into pET28a expression vector for the production of 6X His-tagged protein in Escherichia coli BL21 (DE3) strain. Although initially most of the enzyme was obtained as insoluble protein aggregates, solubilization of protein was improved by optimization of protein induction with respect to growth temperature and isopropyl β-D-1-thiogalactopyranoside concentrations. The induced protein was purified by immobilized metal affinity chromatography using nickel-nitrilotriacetic acid resin in a phosphate-free buffer leading to an accurate SBPase activity measurement. The present study demonstrates, for the first time, successful cloning of C. reinhardtii CC-503 SBPase in E. coli leading to the expression of a functionally active enzyme.

PURPOSE To determine macular thickness and its variation with age and sex in healthy Indian eyes using Zeiss spectral domain optical coherence tomography (SD-OCT). DESIGN A prospective, cross-sectional study. METHODS Four hundred healthy adult subjects (≥18 years) underwent macular cube scanning using Zeiss SD-OCT. Macular thickness from all 9 regions of the Early Treatment Diabetic Retinopathy Study map was documented for each subject. Variations in macular thickness by age and sex were determined. RESULTS The mean age of the subjects was 38.05 ± 12.13 (range, 18-78) years. The mean ages in men and women were 39.19 ± 12.16 and 37.13 ± 12.05 years, respectively (P > 0.05). The mean central subfield thickness (CST) of all subjects was 240.40 ± 18.26 μm, and mean macular thickness was 287.87 ± 18.07 μm. The mean CST in the right and left eyes were 240.40 ± 18.25 μm and 239.65 ± 17.73 μm, respectively (P = 0.55). Males were associated with greater mean CST and mean macular thickness compared with females (P < 0.05). There was an association of mean CST with sex (adjusted r = 0.095; P < 0.05) but not with age. Overall, the nasal quadrant was the thickest followed by the superior, inferior, and temporal subfields. CONCLUSIONS This is the normative data for macular thickness in healthy Indian eyes using Zeiss SD-OCT. This will serve as a baseline for diagnosing and treating macular pathologies in Indian eyes because such data using Zeiss SD-OCT in Indian eyes have previously been lacking.

Asterarcys is a resilient microalgal species which can sustain high light intensities and have high biomass and lipid productivity under mixotrophy. These attributes make it a potential candidate to produce biodiesel and biofuels. However, no genetic information is currently available for this species. Here, we report the chloroplast genome sequence of Asterarcys sp. and compare it with the chloroplast genome of closely related chlorophyceaen microalgae. The chloroplast genome of Asterarcys sp. is present as a ~111 kb circular molecule with 88 genes and a coding density of 50.28%. The 111,776 bp genome shows a quadripartite structure with two 6297 bp long inverted repeats separating single copy regions (SSC) of almost equal sizes. The small and compact genome of Asterarcys shows similarity in gene structure and organization with that of its closest relative Scenedesmus obliquus. It reinforces the compact nature of chloroplast genomes of Sphaeropleales as compared to that of inflated genomes in Chlamydomonadales. The genome shows a biased distribution of genes with 50 of the protein-coding genes encoded from one strand and 15 from the opposite strand. This biased distribution of genes is likewise to that of Scenedesmus obliquus. The phylogenetic tree based on protein-coding genes from chlorophycean species places Asterarcys close to Scenedesmus. The chloroplast genome information of Asterarcys will help understand the phylogeny of Sphaeropleales and Chlorophyceae. In the present study, we also report a simple and effective method for isolation of Asterarcys sp. chloroplast DNA of high quality and purity which is an essential prerequisite for efficient genome sequencing.

In plants, a mutation in the Orange (Or) gene is known to enhance the accumulation of carotenoids in comparison to the wild-type (WT) allele. We investigated the effect of a point mutation in the Or gene of Brassica oleracea on its protein structure via in silico analysis. Subsequently we studied the effect of the Or mutation on carotenoid regulation in Chlamydomonas reinhardtii. The Or mutation in Brassica oleracea—mBoOr (R88H)—results in a small β-sheet in place of the α-helix that is present in the WT protein, and was found to be associated with enhanced carotenoid content when screened in Escherichia coli. The expression of the equivalent mutant from C. reinhardtii—mCrOr (R106H)—did not result in any change in protein structure and exhibited lower levels of carotenoid in E. coli. An in silico analysis of microalgal genomes revealed the presence of Or homologues in several microalgae from the class Trebouxiphyceae, while C. reinhardtii was the only representative of the Chlorophyceae. The heterologous expression of mBoOr in C. reinhardtii resulted in a 1.7-fold increase in carotenoid content, as well as an increase in cell size and the appearance of multicellularity in C. reinhardtii, which was evidenced by the presence of both orange and green transgenic cells grouping together as a population. A palmelloid formation of the orange and green cells impaired the motility of the transgenic population, resulting in flocculation. This study establishes mBoOr expression as a promising strategy for enhancing carotenoid content in microalgae.

Retinal diseases are significant by increasing problem in every part of the world. While excellent treatment has emerged for various retinal diseases, treatment for early disease is lacking due to an incomplete understanding of all molecular events. With aging, there is a striking accumulation of neutral lipids in Bruch’s membrane. These neutral lipids leads to the creation of a lipid wall at the same locations where drusen and basal linear deposit, pathognomonic lesions of Age-related macular degeneration, subsequently form. High lipid levels are also known to cause endothelial dysfunction, an important factor in the pathogenesis of Diabetic Retinopathy. Various studies suggest that 20 % of Retinal Vascular Occlusion is connected to hyperlipidemia. Biochemical studies have implicated mutation in gene encoding ABCA4, a lipid transporter in pathogenesis of Stargardt disease. This article reviews how systemic and local production of lipids might contribute to the pathogenesis of above retinal disorders.

Parachlorella kessleri is a unicellular alga which grows in fresh as well as marine water and is commercially important as biomass/lipid feedstock and in bioremediation. The present study describes the successful transformation of marine P. kessleri with the help of Agrobacterium tumefaciens. Transformed marine P. kessleri was able to tolerate more than 10 mg l(-1) hygromycin concentration. Co-cultivation conditions were modulated to allow the simultaneous growth of both marine P. kessleri and A. tumefaciens. For co-cultivation, P. kessleri was shifted from Walne's to tris acetate phosphate medium to reduce the antibiotic requirement during selection. In the present study, the transfer of T-DNA was successful without using acetosyringone. Biochemical and genetic analyses were performed for expression of transgenes by GUS assay and PCR in transformants. Establishment of this protocol would be useful in further genetic modification of oil-bearing Parachlorella species.

Azadirachtin is considered as the best pesticide among the biopesticides available in market for crop protection due to its broad spectrum activity and varying mode of action. To meet the increasing demand and primarily due to geographical and variability limitations, its biotechnological production from plant cell culture has gained momentum in last two decades. The major requirement for economic production is to increase the yield as well as the productivity of Azadirachtin production in the bioreactor. In general, different strategies used in the plant cell culture result in either yield or productivity enhancement. The simultaneous increase of both the parameters has remained a challenging task, particularly in plant cell cultivations. In this work, an integrated approach has been adopted by combining the various yield as well as productivity enhancement strategies, i.e. coupling the mathematical model–derived nutrient-feeding strategy for continuous cultivation with elicitation, precursor addition, and permeabilization, etc. With this integrated approach, a yield of 0.0122 g/g and a productivity of 7.25 × 10−4 g/l/h Azadirachtin were obtained, which is so far highest in plant cell suspension culture of Azadirachta indica to the best of our knowledge. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.

Suspension culture of Azadirachta indica produces the biopesticide azadirachtin. Some elicitors (salicylic acid, chitosan, jasmonic acid, methyl jasmonate, yeast extract and yeast extract carbohydrate fraction) at different concentrations were added in shake flask suspension culture of A. indica. Chitosan, salicylic acid and jasmonic acid stimulated the highest increase in azadirachtin content, which ranged from 2 to 3-fold greater than the control. The combined effect of these elicitor(s) on azadirachtin content was then studied by Response Surface Methodology. A synergistic effect of these elicitor(s) on azadirachtin production resulted in 5-fold higher azadirachtin production (15.9 mg/g DCW versus 3.2 mg/g in control cultures). Exposure time studies with elicitor(s) addition on 8th day revealed that highest azadirachtin accumulation reached after 48 h of combined addition of elicitor(s) (17.4 mg/g). Cultivation of A. indica cells was also carried out with combined (statistically optimized) elicitors addition on 8th day in Stirred Tank Bioreactor. This led to more than 3-fold greater azadirachtin accumulation (161.1 mg/l) as opposed to control bioreactor with no elicitor addition (50 mg/l) in 10 days of cultivation period. The present study not only identifies the elicitor(s) and their respective concentrations for enhanced azadirachtin synthesis but also establishes the role of combined elicitors to improve secondary metabolite production of plant cell cultures more efficiently.

Successful scale-up of Azadirachta indica suspension culture for azadirachtin production was done in stirred tank bioreactor with two different impellers. The kinetics of biomass accumulation, nutrient consumption and azadirachtin production of A. indica cell suspension culture were studied in a stirred tank bioreactor equipped with centrifugal impeller and compared with similar bioreactor with a setric impeller to investigate the role of O 2 transfer efficiency of centrifugal impeller bioreactor on overall culture metabolism. The maximum cell mass for centrifugal impeller bioreactor and stirred tank bioreactor (with setric impeller) were 18.7 and 15.5 g/L (by dry cell weight) and corresponding azadirachtin concentrations were 0.071 and 0.05 g/L, respectively. Glucose and phosphate were identified as the major growth-limiting nutrients during the bioreactor cultivation. The centrifugal impeller bioreactor demonstrated less shearing and improved O 2 transfer than the stirred tank bioreactor equipped with setric impeller with respect to biomass and azadirachtin production.

Central serous chorioretinopathy (CSCR) is an incompletely understood multifactorial disease of those who are middle aged characterized by the collection of fluid between the retinal pigment epithelium and the neurosensory retina. The exact etiology of CSCR and the reason of its predominance in middle-aged males are still unknown. Many pharmacologic modalities are suggested for CSCR with no proven efficacy. So this article was written to give a review of the relevant and recent literature on CSCR and to summarize the etiology, clinical features, and diagnostic modalities for CSCR with special emphasis on the treatment options available and those that are still under trial and can be of help in the future to fasten the recovery and reduce the recurrences.

Azadirachtin, obtained from Azadirachta indica (neem) has emerged as wonderful natural biopesticide for pest control due to its efficacy, biodegradability and minimum side effects. To overcome constraints associated with its limited, variable and unreliable supply from natural trees, plant cell suspension culture of A. indica was developed (obtained from callus of seeds). The kinetics of cell growth/azadirachtin formation and substrate consumption of A. indica suspension culture was established in bioreactor with low shear setric impeller under optimized culture conditions (statistically optimized independently). The culture featured a growth of 15.5 and 0.05 g/l azadirachtin in 10 days of cultivation after which azadirachtin concentration declined. To prevent any inhibition caused by the excess feeding of substrate during fed-batch cultivation, inhibition of the carbon, nitrate and phosphate were separately established. Based on batch kinetics/inhibitory data a mathematical model was proposed and model parameters were evaluated. The model was extrapolated to fed-batch cultivation and nutrient feeding strategy (with respect to carbon, nitrate and phosphate) were computer simulated for a suitable fed-batch cultivation of A. indica cells to enhance growth and product formation. Fed-batch cultivation demonstrated a growth of 20.06 g/l biomass and 0.082 g/l of azadirachtin in 14 days of cultivation. A 30% increase in cell growth and 83% increase in azadirachtin production were obtained when a computer simulated feeding strategy was experimentally implemented in 3 l bioreactor.

Azadirachtin is one of the most widely used biopesticide originating from a plant source. Its production from plant cell cultivation was viewed to overcome constraints associated with its regular supply from the seed kernels. In order to select the effective carbon and nitrogen source, different concentrations of carbon (sucrose/glucose) and nitrogen (NO 3 − /NH 4 + ratio) were studied in A. indica suspension culture. Glucose turned out to be a better carbon source over sucrose yielding high biomass (6.32 g/L) and azadirachtin (11.12 mg/L) content. Nitrate alone as nitrogen source was favorable for both biomass and azadirachtin accumulation. Plackett–Burman design was adopted to select the most important nutrients influencing the growth and azadirachtin accumulation in suspension culture. After identifying effective nutrients, Central Composite Design (CCD) was used to develop mathematical model equations, study responses and establish the optimum concentrations of the key nutrients for higher growth and azadirachtin production. A maximum of 15.02 g/L biomass and 2.98 mg/g azadirachtin was produced using optimum nutrient concentrations representing 99 and 96% validity of the model prediction with respect to biomass and azadirachtin, respectively. This optimized media can be used for cultivation of A. indica cells in bioreactor for mass production of azadirachtin.

Case report: We document a previously unreported association of Vogt-Koyanagi-Harada (VKH) syndrome with intracranial meningioma. A female patient with diminished vision, exudative retinal detachment, and headache was diagnosed with VKH syndrome, more precisely a Harada form of disease with intracranial meningioma, on the basis of exudative retinal detachment, typical fundus fluorescein findings, and magnetic resonance imaging. With intravenous steroid therapy, visual acuity improved and the detachment settled within a week. At 3 months, the detachment recurred but improved after retreatment. At I year, the tumour was unchanged in size. Comments: VKH syndrome may be associated with intracranial meningioma that may affect the patient's overall morbidity or mortality.

Seeds of neem were collected from different parts of India and analyzed for their azadirachtin content by High Performance Liquid Chromatography (HPLC). In order to assess the effects of genotypic and geographical variation on azadirachtin content in cell cultures, callus development was attempted in the seeds containing high and low concentration of azadirachtin. The concentration of azadirachtin in callus cultures was significantly affected by the explant source. Seed kernels with higher azadirachtin content produced higher azadiractin content in callus cultures and lower azadirachtin content was seen in callus cultures produced from seed kernels with low azadiractin content. The protocol for development of elite stock culture ofAzadirachta indica was established with the objective of selecting a high azadirachtin-producing cell line. The highest azadirachtin-producing cell line was selected and the effects of different media and illumination conditions on growth and azadirachtin production were studied in shake flask suspension culture. Detailed batch growth kinetics was also established. These studies provided elite starter culture and associated protocols for cultivation ofA. indica plant cell culture in the bioreactor.

Purpose To investigate and report the reliability of detection and grading of diabetic retinopathy by direct ophthalmoscopy through a dilated pupil by general physicians (non-ophthalmologists) and optometrists who have undergone a short period of training. Methods A total of 400 eyes of 200 diabetes patients were examined by two non-ophthalmologists. Their observations were compared with an ophthalmologist's diagnoses for the same patients. Results The diagnoses made by the general physician (kappa = 0.8381, SE = 0.041) and the optometrist (kappa = 0.7186, SE = 0.051) showed good rates of agreement with the ophthalmologist's diagnoses. Conclusions The provision of appropriate screening protocols and follow-up parameters can enable primary care physicians and support personnel to reliably screen individuals for retinopathy in diabetes. This will reduce the workload of tertiary hospitals, and provide optimal services to the huge majority of the Indian population that has limited access to eye care services.

The effect of major nutrients on growth and azadirachtin-related limonoids (AZRL) production in plant cell culture of Azadirachta indica (neem) was studied with the objective to increase the yield of AZRL, one of the major group of pesticidal compounds found in intact neem tees. We report the novel online monitoring of plant cell respiration activities in a new parallel shake flask measuring device. Results obtained using three standard plant cell culture media showed non-growth-associated production characteristics for AZRL. These findings were supported by the oxygen uptake rate data. Further investigations on AZRL production in a modified MS medium with different concentrations of nitrogen and phosphorus sources resulted in 0.25 mg × g(exp -1) dry weight of AZRL, compared to no detectable AZRL production in standard MS media. These characteristics suggest the necessity of a two-stage process for the production of AZRL in plant cell culture. Compared to the single-stage process, an almost twofold increase in the volumetric productivity of AZRL was achieved using the two-stage process.

With increasing awareness towards environment-friendly and non-toxic pesticide azadirachtin obtained from neem tree (Azadirachta indica) is gaining more and more importance. Its broad-spectrum activity, peculiar mode of action. eco-friendly and non-toxic action towards beneficial organisms has offered many advantages over chemical pesticides. All currently use commercial formulations based on azadirachtin contains azadirachtin extracted from seeds of naturally grown whole plants which is labour intensive process depending upon many uncontrollable geographical and climatic factors. Plant tissue culture can be a potential process for the production, offering consistent, stable and controlled supply of this bioactive compound, However the research on tissue culture aspects of production are in preliminary stage and requires culture and process optimization for the development of a commercially viable process. This review states the present status and future challenges of plant tissue culture for azadirachtin production.

Central serous chorioretinopathy (CSC) is characterized by serous retinal detachment at the posterior pole. Several factors have been implicated in the pathogenesis, and endogenous or exogenous corticosteroids are thought to play a major role. Here we present a case of a 35-year-old male with complaints of a dark circle in front of his right eye. Fundus examination, optical coherence tomography and fundus fluorescein angiography were performed. The patient was diagnosed with CSC. CSC resolved completely within seven weeks. Four weeks later the CSC recurred and spontaneously resolved over eight weeks. Overall, the patient had three additional recurrences of CSC in the same eye over the next year. A detailed history taking revealed the patient was using 0.1% dexamethasone eye drops nasally for recurrent rhinitis for few days prior to each episode of CSC. This indicates the strong correlation between steroids given by any route and the pathogenesis of CSC.

A two and half year old female was admitted at the emergency room suffering from gradually worsening headache followed by nausea. The child presented with reduced level of consciousness and bilateral hypoacusis. The patient was lethargic. Ophthalmic examination showed branch retinal artery occlusion (BRAO). This finding was crucial to the diagnosis of Susac's syndrome (SS), a rare autoimmune disease characterized by, endotheliopathy of retina, encephalic tissues and cochlea. Magnetic resonance imaging of the brain also showed typical features. Thorough blood investigations did not reveal any other abnormality. Patient was treated with immunosuppressive to prevent her from developing severe sequelae of this disease. The child showed dramatic improvement in her systemic condition within 48 h of starting the treatment. This is the youngest ever and first case report from India.

The seeds of Azadirachta indica contain azadirachtin and other limonoids, which can be used as a biopesticide for crop protection. Significant variability and availability of seed only in arid zones has triggered biotechnological production of biopesticides to cope up with its huge requirement. Batch cultivation of A. indica suspension culture was carried out in statistically optimized media (25.0 g/l glucose, 5.7 g/l nitrate, 0.094 g/l phosphate and 5 g/l inoculum) in 3 l stirred tank bioreactor. This resulted in 15.5 g/l biomass and 0.05 g/l azadirachtin production in 10 days leading to productivity of 5 mg l(-1) day(-1). Possible inhibition by the limiting substrates (C, N, P) were also studied and maximum inhibitory concentrations identified. The batch kinetic/inhibitory data were then used to develop and identify an unstructured mathematical model. The batch model was extrapolated to simulate continuous cultivation with and without cell retention in the bioreactor. Several offline computer simulations were done to identify right nutrient feeding strategies (with respect to key limiting substrates; carbon, nitrate and phosphate) to maintain non-limiting and non-inhibitory substrate concentrations in bioreactor. One such continuous culture (with cell retention) simulation was experimentally implemented. In this cultivation, the cells were propagated batch-wise for 8 days. It was then converted to continuous cultivation by feeding MS salts with glucose (75 g/l), nitrate (10 g/l), and phosphate (0.5 g/l) at a feed rate of 500 ml/day and withdrawing the spent medium at the same rate. The above continuous cultivation (with cell retention) demonstrated an improvement in cell growth to 95.8 g/l and intracellular accumulation of 0.38 g/l azadirachtin in 40 days leading to an overall productivity of 9.5 mg l(-1) day(-1).

We describe a previously unreported co-existence of retinitis pigmentosa and congenital toxoplasmosis. An eight year old male presented to our center with complaints of decreased night vision. Fundus evaluations in both the eyes demonstrated features typical of retinitis pigmentosa. There were well-defined punched out healed chorio-retinal scars suggestive of congenital toxoplasmosis. On the basis of history, clinical findings and reduction of a and b wave amplitudes on scotopic and photopic electroretinograph, a diagnosis of retinitis pigmentosa with congenital toxoplasmosis was made. Retinitis pigmentosa may co-exist with congenital toxoplasmosis that may affect the patient's overall ocular morbidity and visual acuity.

To investigate and report the reliability of detection and grading of diabetic retinopathy by direct ophthalmoscopy through a dilated pupil by general physicians (non-ophthalmologists) and optometrists who have undergone a short period of training.A total of 400 eyes of 200 diabetes patients were examined by two non-ophthalmologists. Their observations were compared with an ophthalmologist's diagnoses for the same patients.The diagnoses made by the general physician (kappa = 0.8381, SE = 0.041) and the optometrist (kappa = 0.7186, SE = 0.051) showed good rates of agreement with the ophthalmologist's diagnoses.The provision of appropriate screening protocols and follow-up parameters can enable primary care physicians and support personnel to reliably screen individuals for retinopathy in diabetes. This will reduce the workload of tertiary hospitals, and provide optimal services to the huge majority of the Indian population that has limited access to eye care services.