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1.
Bioresour Technol ; 351: 126956, 2022 May.
Article in English | MEDLINE | ID: mdl-35272039

ABSTRACT

In the present work, Aspergillus niger was employed to produce commercially valuable malic acid from crude glycerol derived from waste cooking oil. Crude glycerol dosage, yeast extract dosage and initial pH were the influencing factors playing a significant role in the malic acid synthesis. The optimal condition for malic acid biosynthesis was studied by using response surface methodology. Further the feasibility analysis for biosynthesis of malic acid from crude glycerol was studied using the laboratory scale optimized data, with this experimentally optimized data, plant was simulated using SuperPro Designer (v10). The cost involved for malic acid synthesis per unit volume was likely expected to be $0.43/kg of malic acid using reactive extraction method. Thus, process optimization combined with techno-economical analysis of malic acid production could be beneficial.


Subject(s)
Glycerol , Malates , Aspergillus niger , Cooking
2.
Bioresour Technol ; 346: 126405, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34826562

ABSTRACT

Microbial reduction of black strap molasses (BSM) by Clostridium acetobutylicum MTCC 11,274 was performed for the production of biobutanol. The optimum fermentation conditions were predicted using one factor at a time (OFAT) method. The identification of significant parameters was performed using Plackett-Burman Design (PBD). Furthermore the fermentation conditions were optimized using central composite design (CCD). The kinetics of substrate utilization and product formation were investigated. Initial pH, yeast extract concentration (g/L) and total reducing sugar concentration (g/L) were found as significant parameters affecting butanol production using C. acetobutylicum MTCC11274. The maximum butanol production under optimal condition was 10.27 + 0.82 g/L after 24 h. The waste black strap molasses obtained from sugar industry could be used as promising substrate for the production of next generation biofuel.


Subject(s)
Clostridium acetobutylicum , Anaerobiosis , Butanols , Fermentation , Kinetics , Molasses
3.
Environ Monit Assess ; 192(2): 102, 2020 Jan 08.
Article in English | MEDLINE | ID: mdl-31915929

ABSTRACT

Groundwater quality investigations were carried out in one of the urban parts of south India for fluoride and nitrate contaminations, with special focus on human health risk assessment for the rapidly growing and increasingly industrialized Coimbatore City. Twenty-five groundwater samples were collected and analyzed for physico-chemical parameters (EC, pH, TDS, Ca2+, Mg2+, Na+, K+, Cl-, SO42-, HCO3-, PO43-, NO3-, and F-) and the piper diagram characterized 60% of them as Ca-Mg-Cl type. Analysis of fluoride (0.1 to 2.4 mg/l) shows that 32% of the groundwater samples contain F- over the permissible limit, affecting a region of 122.10 km2. Nitrate (0.1 to 148 mg/l) is over the permissible limit in 44% of the groundwater samples spread over an area of 429.43 km2. The total hazard indices (THI) of non-carcinogenic risk for children (0.21 to 4.83), women (0.14 to 3.35), and men (0.12 to 2.90) shows some of the THI values are above the permissible limit of the US Environmental Protection Agency. The THI-based non-carcinogenic risks are 60%, 52%, and 48% for children, women, and men. This investigation suggests higher health risk for children and also recommends that proper management plan should be adopted to improve the drinking water quality in this region in order to avoid major health issues in the near future.


Subject(s)
Fluorides/analysis , Groundwater/chemistry , Nitrates/analysis , Water Pollutants, Chemical/analysis , Drinking Water/standards , Environmental Monitoring , Fluorides/standards , Humans , India , Nitrates/standards , Nitrogen Oxides/analysis , Sodium/analysis , Water Pollutants, Chemical/standards
4.
Bioresour Technol ; 293: 122060, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31514122

ABSTRACT

In the present study, Kluyveromyces marxianus was utilized to study the batch fermentation kinetics of biomass production, substrate utilization and bioethanol production from woody stem Prosopis juliflora. The pre-treated substrate was subjected to Simultaneous Saccharification and Fermentation (SSF) under optimised conditions of pH (4.9), temperature (41 °C), substrate concentration 5% (w/v), inoculum concentration 3% (v/v) and the maximum concentration of bioethanol was found to be 21.45 g/l. The experimental data thus obtained from cell growth, substrate utilization and product formation are employed in the determination of kinetic parameters. Biological models such as Logistic model, Hinshelwood model were used for microbial growth and substrate utilization kinetics respectively. In case of product kinetics, Leudking-Piret plot, Gompertz model and Modified Gompertz model were utilised. Based on these models, kinetic parameters like maximum specific growth rate (µm), saturation constant (Ks), growth associated (α), non-growth associated (ß) and yield coefficients (YX/S, YP/S) were estimated.


Subject(s)
Kluyveromyces , Prosopis , Ethanol , Fermentation , Kinetics
5.
Bioresour Technol ; 271: 345-352, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30293029

ABSTRACT

In the present work, palm wood was pretreated using hydrothermal technique in conjunction with chemical method for removal of lignin. Pretreated palm wood was subjected to hydrolysis using Trichoderma reesei MTCC 4876. Subsequently bioethanol was produced using palm wood hydrolysate by Kluveromyces marxianus MTCC 1389. RSM was used to identify the non-linear relationship and optimize various process parameters such as parameters such as pH, temperature, agitation rate, substrate concentration and inoculum size for bioethanol production. ANN constructed with 5-2-1 topology was also used to optimize process parameters. The experimental bioethanol yield of 22.90 g/l was obtained at ANN optimum conditions of temperature 45 °C, agitation rate 156 rpm, pH 5, substrate concentration 8% (v/v) and inoculum size 3.2% (v/v).


Subject(s)
Arecaceae/metabolism , Ethanol/metabolism , Trichoderma/metabolism , Fermentation , Hydrolysis , Lignin/metabolism , Temperature , Wood/metabolism
7.
Bioresour Technol ; 239: 538-541, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28549810

ABSTRACT

In the present study Trichoderma reesei, a wood isolate can yield high biomass quantities up to 30g/L, yielding 32.4% of lipids of dry cell weight (DCW). Biodiesel production from Trichoderma reesei involved simple unit operations like filtration and ultrasonication, yet giving good lipid yield with desirable bio-diesel properties. Optimization of ultrasonication conditions was done to ensure maximum lipid extraction. SEM analysis of ultrasonicated samples showed distinct breakage of fungal hyphae. The lipids were found to contain 49.7% saturated fatty acids. Transesterification using chemical and biological catalysts were compared and 96.09% efficiency was observed for lipase-catalyzed transesterification. The bio-diesel properties satisfied ASTM and EN specifications with cetane number: 53.1, iodine value: 63.34g, saponification value: 235.07mg KOH/g, cold flow plugging point: 9.13°C.


Subject(s)
Biofuels , Trichoderma , Wood , Fatty Acids , Lipids
8.
Bioresour Technol ; 233: 423-432, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28314666

ABSTRACT

Microbes have recourse to low-priced substrates like agricultural wastes and industrial efflux. A pragmatic approach towards an emerging field- the exploitation of microbial oils for biodiesel production, pharmaceutical and cosmetic applications, food additives, biopolymer production will be of immense remunerative significance in the near future. Due to high free fatty acid, nutritive content and simpler solvent extraction processes of microbial oils with plant oil, microbial oils can back plant oils in food applications. The purpose of this review is to evaluate the opulence of lipid production in native and standard micro-organisms and also to emphasize the vast array of applications including food and fuel by obtaining maximum yield.


Subject(s)
Biofuels , Agriculture , Esterification , Fatty Acids, Nonesterified , Lipids , Oils , Plant Oils/chemistry
9.
J Postgrad Med ; 62(4): 260-263, 2016.
Article in English | MEDLINE | ID: mdl-27763485

ABSTRACT

Hyperemesis gravidarum-induced Wernicke's encephalopathy (WE) is an underestimated condition. The purpose of this study is to improve its awareness and early diagnosis. We report five cases of WE secondary to hyperemesis gravidarum. Classic triad of encephalopathy, ataxia, and ocular signs was seen in four out of five patients. Two unusual features noted in this series were papilledema in one patient and severe sensory-motor peripheral neuropathy in one patient. Magnetic resonance imaging (MRI) was abnormal in all the five patients, and high signal in medial thalamus and surrounding the aqueduct was the most common abnormality (5/5). Involvement of caudate nucleus was seen in two patients with severe psychosis, and two patients had bilateral cerebellar peduncle involvement. Median time delay between onset of neurological symptoms and diagnosis was 7 days. All patients improved with thiamine, but minor sequelae were seen in four patients at 12 months follow-up. One patient had a fetal demise. Hyperemesis gravidarum-induced WE is a common cause of maternal morbidity. Typical MRI findings of symmetric medial thalamic and periaqueductal signal changes may permit a specific diagnosis. A delay in diagnosis, therefore treatment, leads to worse prognosis.


Subject(s)
Hyperemesis Gravidarum/complications , Thiamine/administration & dosage , Wernicke Encephalopathy/diagnosis , Wernicke Encephalopathy/etiology , Adult , Ataxia/etiology , Female , Humans , Injections, Intramuscular , Magnetic Resonance Imaging , Pregnancy , Thiamine Deficiency , Treatment Outcome , Wernicke Encephalopathy/drug therapy , Wernicke Encephalopathy/pathology
10.
Bioresour Technol ; 213: 69-78, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26906444

ABSTRACT

In this investigation, oil extraction was performed in marine macroalgae Gracilaria edulis, Enteromorpha compressa and Ulva lactuca. The algal biomass was characterized by Scanning Electron Microscopy and Fourier Transform-Infra Red Spectroscopy. Six different pre-treatment methods were carried out to evaluate the best method for maximum oil extraction. Optimization of extraction parameters were performed and high oil yield was obtained at temperature 55°C, time 150min, particle size 0.10mm, solvent-to-solid ratio 6:1 and agitation rate 500rpm. After optimization, 9.5%, 12.18% and 10.50 (g/g) of oil extraction yield was achieved from the respective algal biomass. The rate constant for extraction was obtained as first order kinetics, by differential method. Stable intracellular Cal A and Cal B lipase producing recombinant Pichia pastoris was constructed and used as biocatalyst for biodiesel production. Comparative analysis of lipase activity and biodiesel yield was made with immobilized Candida antarctica lipase.


Subject(s)
Biofuels , Biotechnology/methods , Enzymes, Immobilized/metabolism , Lipase/metabolism , Oils/metabolism , Pichia/metabolism , Seaweed/metabolism , Biocatalysis , Biofuels/analysis , Cooking , Esterification , Fatty Acids/analysis , Kinetics , Spectroscopy, Fourier Transform Infrared , Ulva/metabolism , Waste Products
11.
Ann Indian Acad Neurol ; 18(2): 162-6, 2015.
Article in English | MEDLINE | ID: mdl-26019412

ABSTRACT

BACKGROUND: Low rates of thrombolysis for ischemic stroke in India and other developing countries have been attributed to delays in presentation to the hospital. MATERIALS AND METHODS: A prospective study was carried out during a 12-month period ending December 2012 in the department of Neurology, Malabar Institute of Medical Sciences, Kerala, India, to look for the factors contributing to delay in hospital arrival of patients with acute stroke. Patients and or their relatives were interviewed within 48 hours of admission using a structured questionnaire. RESULTS: A total of 264 patients attending the emergency department were included. There were 170 men and 94 women. The mean age was 61.5 ± 12.4 years. A total of 67 (25%) patients presented within 4 hours of stroke onset. Factors associated with early arrival (multivariate logistic regression analysis) were distance 15 km or less from hospital (P 0.03, odds ratio (OR) 2.7), directly reaching the stroke department (P < 0.001, OR 9.7), history of coronary artery disease (P 0.001, OR 3.84), higher educational status (P 0.001, OR 3.7), and presence of hemiplegia (P 0.001, OR 5.5). CONCLUSIONS: We found a considerable delay in the early arrival of patients to our stroke department. Health promotion strategies to improve community awareness of early symptoms of stroke, education of local physicians about the importance of early referrals to the stroke centers, and wider availability and use of ambulance services are promising methods to help expedite presentation to hospital post stroke and thereby improve the management of stroke in India.

12.
Lett Appl Microbiol ; 59(5): 535-41, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25070401

ABSTRACT

UNLABELLED: This study investigated the effect of pesticide chlorpyrifos (CP) on a freshwater cyanobacterium Chroococcus turgidus NTMS12. The changes in chlorophyll-a, proline, superoxide dismutase (SOD), catalase (CAT) activities and fatty acid composition of the test organism were analysed. Organism was grown at 6, 9 and 12 mg l(-1) of CP, and based on the chlorophyll-a content, 6 mg l(-1) of CP was found to be the tolerable concentration. Hence, 6 mg l(-1) of CP was taken to evaluate the concentration of proline and activities of SOD and CAT at 48-h exposure. The changes in the fatty acid profile were analysed after 7 days of exposure. Upon pesticide exposure, increased concentration of proline and activities of SOD and CAT were found. Significant changes in fatty acid profile have also been observed. However, polyunsaturated fatty acid content was decreased in treated cultures when compared with the untreated control. Changes in biochemical activities indicate that cyanobacteria C. turgidus NTMS12 undergo adaptive changes against CP-induced oxidative stress. SIGNIFICANCE AND IMPACT OF THE STUDY: : Chlorpyrifos induces oxidative stress in Chroococcus turgidus NTMS12. A strong inference was made on increased activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and proline content and lowering the level of unsaturated fatty acids under the pesticide-exposed condition. These significant changes are the defence mechanisms against the oxidative stress. Thus, this organism holds great promise in resisting toxic pesticide.


Subject(s)
Antioxidants/metabolism , Chlorpyrifos/toxicity , Cyanobacteria/drug effects , Cyanobacteria/metabolism , Fatty Acids/metabolism , Insecticides/toxicity , Catalase/metabolism , Chlorophyll/metabolism , Chlorophyll A , Cyanobacteria/enzymology , Fresh Water/microbiology , Oxidative Stress , Proline/metabolism , Superoxide Dismutase/metabolism
13.
Ann Indian Acad Neurol ; 15(1): 19-22, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22412267

ABSTRACT

INTRODUCTION: An inverse association between serum cholesterol and the risk of hemorrhagic stroke has been noted in epidemiological studies. We performed a case-control study to assess the relationship between primary intracerebral hemorrhage (ICH) and low serum cholesterol. MATERIALS AND METHODS: Prospectively recruited fully evaluated patients with ICH were compared with a control group based in a primary care practice, i.e. age- and sex-matched individuals attending the routine preventive health check-up. Low cholesterol was defined by the sex-specific lowest quintile of the population. RESULTS: The proportion of ICH patients with low cholesterol was significantly higher than the controls (68% vs. 43%). Mean total cholesterol was also signficantly low in ICH patients compared with controls (177 mg/dL vs. 200 mg/dl; P-value = 0.0006). Low-density lipoprotein cholesterol (LDL-c) and triglycerides were also significantly low in ICH patients compared with controls. Mean LDL-C in the ICH patient group was 114 mg/dL, whereas it was 128.5 mg/dL in the control group (P-value = 0.016). There was no significant difference in the high-density lipoprotein (HDL) levels in both groups. In a subgroup analysis, both men and women in the ICH group had a significantly low mean cholesterol compared with the control group. Although lower mean cholesterol was seen in both young and older individuals in the ICH group than in controls, the difference was significant only in the older group (age >45 years). In multivariate analysis, presence of low cholesterol remained a significant predictor of hemorrhage. The odds ratio of low cholesterol in the hemorrhage cases was 2.75 (95% CI = 1.44-5.49) unadjusted and 2.15 (1.13-4.70) adjusted for age and hypertension. CONCLUSIONS: This study confirms an increased risk of primary ICH associated with low cholesterol both in men and women, especially in older individuals.

14.
Neurol India ; 60(6): 635-7, 2012.
Article in English | MEDLINE | ID: mdl-23287328

ABSTRACT

A 42-year-old woman, a diagnosed case of systemic lupus erythematosus (SLE), developed severe headache followed by left hemiparesis and cortical blindness. Magnetic resonance imaging (MRI) of brain demonstrated right parieto-occipital infarct and the patient was initiated on high-dose steroids and antiplatelet agents with which the patient had clinical and radiological deterioration. Magnetic Resonance angiography showed severe narrowing of bilateral anterior, middle, and posterior cerebral arteries (PCA) suggestive of reversible cerebral vasoconstriction syndrome (RCVS). Patient was treated with IV nimodipine and she recovered over a period of 2 weeks. Repeat MR-angiography done on day-30 was normal. The diagnosis of RCVS in patients with SLE is of practical importance, because treatment and prognosis for SLE-associated cerebral vasculitis differ strongly from the treatment of RCVS. Empirical high-dose glucocorticoid therapy should be avoided in patients with typical features of RCVS.


Subject(s)
Lupus Vasculitis, Central Nervous System/complications , Vasoconstriction , Vasospasm, Intracranial/complications , Adult , Brain/diagnostic imaging , Brain/pathology , Female , Humans , Lupus Vasculitis, Central Nervous System/diagnostic imaging , Magnetic Resonance Angiography , Magnetic Resonance Imaging , Middle Cerebral Artery/diagnostic imaging , Middle Cerebral Artery/pathology , Radiography , Vasospasm, Intracranial/diagnostic imaging
15.
J Cancer Res Ther ; 7(3): 308-13, 2011.
Article in English | MEDLINE | ID: mdl-22044813

ABSTRACT

AIM: The aim was to obtain inhomogenity correction factors (ICFs) for lung tissue inhomogenity for a Co-60 teletherapy beam using Monte Carlo simulation and to compare them with factors obtained from a commercially available treatment planning system. MATERIALS AND METHODS: The Monte Carlo simulation code of EGSnrc is used for the depth dose calculations. Two clinical like situations were simulated-dose calculation point beyond the lung tissue volume and dose calculation point within the lung tissue volume. The variation of ICF with lung thicknesses and positions was studied. ICF values were obtained for the similar situations from a commercially available treatment planning system, Theraplan Plus. RESULTS: Percentage depth dose data obtained from Monte Carlo simulation is well matching with the published measurement data. ICFs for lung tissue inhomogenity calculated using the Monte Carlo code are in good agreement with Theraplan Plus TPS values for small inhomogenity thicknesses. CONCLUSION: These results can be used for the verification of TPS calculation or manual treatment time calculation.


Subject(s)
Lung Neoplasms/radiotherapy , Lung , Radioisotope Teletherapy/methods , Radiometry , Radiotherapy Planning, Computer-Assisted/methods , Body Burden , Cobalt , Humans , Models, Statistical , Monte Carlo Method , Phantoms, Imaging , Radiotherapy Dosage , Relative Biological Effectiveness
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