Search results for: ruminal fermentation
118 Effects of Certain Natural Food Additives (Pectin, Gelatin and Whey Proteins) on the Qualities of Fermented Milk
Authors: Abderrahim Cheriguene, Fatiha Arioui
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The experimental study focuses on the extraction of pectin, whey protein and gelatin, and the study of their functional properties. Microbiological, physicochemical and sensory approach integrated has been implanted to study the effect of the incorporation of these natural food additives in the matrix of a fermented milk type set yogurt, to study the stability of the product during the periods of fermentation and post-acidification over a period of 21 days at 4°C. Pectin was extracted in hot HCl solution. Thermo-precipitation was carried out to obtain the whey proteins while the gelatin was extracted by hydrolysis of the collagen from bovine ossein. The fermented milk was prepared by varying the concentration of the incorporated additives. The measures and controls carried performed periodically on fermented milk experimental tests were carried out: pH, acidity, viscosity, the enumeration of Streptococcus thermophilus, cohesiveness, adhesiveness, taste, aftertaste, whey exudation, and odor. It appears that the acidity, viscosity, and number of Streptococcus thermophilus increased with increasing concentration of additive added in the experimental tests. Indeed, it seems clear that the quality of fermented milk and storability is more improved than the incorporation rate is high. The products showed a better test and a firmer texture limiting the whey exudation.Keywords: fermented milk, pectin, gelatin, whey proteins, functional properties, quality, conservation, valorization
Procedia PDF Downloads 136117 Production of Novel Antibiotics of Tylosin by Importing eryK and eryG Genes in Streptomyces fradiae
Authors: Neda Gegar Goshe, M. Moradi, Hossein Rassi
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The antibacterial properties of macrolide antibiotics (such as erythromycin and tylosin) depend ultimately on the glycosylation of otherwise inactive polyketide lactones. Among the sugars commonly found in such macrolides are various 6-deoxyhexoses including the 3-dimethylamino sugars mycaminose and desosamine (4-deoxymycaminose). Some macrolides (such as tylosin) possess multiple sugar moieties, whereas others (such as erythromycin) have two sugar substituents. Streptomyces fradiae is an ideal host for development of generic polyketide-overproducing strains because it contains three of the most common precursors-malonyl-CoA, methylmalonyl-CoA and ethylmalonyl-CoA-used by modular PKS, and is a host that is amenable to genetic manipulation. As patterns of glycosylation markedly influence a macrolide's drug activity, there is considerable interest in the possibility of using combinatorial biosynthesis to generate new pairings of polyketide lactones with sugars, especially 6-deoxyhexoses. Here, we report a successful attempt to alter the aminodeoxyhexose-biosynthetic capacity of Streptomyces fradiae (a producer of tylosin) by importing genes from the erythromycin producer Saccharopolyspora erythraea. The bio transformation of erythromycin-D into the desired major component erythromycin-A involves two final enzymatic reactions, EryK-catalyzed hydroxylation at the C-12 position of the aglycone and EryG-catalyzed O methylation at the C-3 position of macrose. This engineered S. fradiae produced substantial amounts of two potentially useful macrolides that had not previously been obtained by fermentation.Keywords: tylosin, eryK and eryG genes, streptomyces fradiae
Procedia PDF Downloads 352116 Effects of Multilayer Coating of Chitosan and Polystyrene Sulfonate on Quality of ‘Nam Dok Mai No.4’ Mango
Authors: N. Hadthamard, P. Chaumpluk, M. Buanong, P. Boonyaritthongchai, C. Wongs-Aree
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Ripe ‘Nam Dok Mai’ mango (Mangifera indica L.) is an important exported fruit of Thailand, but rapidly declined in the quality attributes mainly by infection of anthracnose and stem end rot diseases. Multilayer coating is considered as a developed technique to maintain the postharvest quality of mangoes. The utilization of alternated coating by matching oppositely electrostatic charges between 0.1% chitosan and 0.1% polystyrene sulfonate (PSS) was studied. A number of the coating layers (layer by layer) were applied on mature green ‘Nam Dok Mai No.4’ mangoes prior to storage at 25 oC, 65-70% relative humidity (RH). There were significant differences in some quality attributes of mangoes coated by 3½ layers, 4½ layers and 5½ layers. In comparison to coated mangoes, uncoated fruits were higher in weight loss, total soluble solids, respiration rate, ethylene production and disease incidence except the titratable acidity. Coating fruit at 3½ layers exhibited the ripening delay and reducing disease infection without off flavour. On the other hand, fruit coated with 5½ layers comprised the lowest acceptable score, caused by exhibiting disorders from fermentation at the end of storage. As a result, multilayer coating between chitosan and PSS could effectively maintain the postharvest quality of mango, but number of coating layers should be thoroughly considered.Keywords: multilayer, chitosan, polystyrene sulfonate, Nam Dok Mai No.4
Procedia PDF Downloads 211115 Encapsulated Rennin Enzyme in Nano and Micro Tubular Cellulose/Starch Gel Composite for Milk Coagulation
Authors: Eleftheria Barouni, Theano Petsi, Argyro Bekatorou, Dionysos Kolliopoulos, Dimitrios Vasileiou, Panayiotis Panas, Maria Kanellaki, Athanasios A. Koutinas
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The aim of the present work was the production and use of a composite filter (TC/starch), containing rennin enzyme, in continuous system and in successive fermentation batches (SFB) for milk coagulation in order to compare the operational stability of both systems and cheese production cost. Tubular cellulose (TC) was produced after removal of lignin from lignocellulosic biomass using several procedures, e.g. alkaline treatment [1] and starch gel was added for the reduction of TC tubes dimensions to micro- and nano- range[2]. Four immobilized biocatalysts were prepared using different ways of the enzyme entrapment. 1) TC/ rennin (rennin entrapped in the tubes of TC), 2) TC/SG-rennin (rennin entrapped in the tubes of the composite), 3) TC-SG/rennin (rennin entrapped into the layer of starch gel) and 4) TC/rennin- SG/rennin (rennin is entrapped both in the tubes of the TC and into the layer of starch gel). Firstly these immobilized biocatalysts were examined in ten SFB regarding the coagulation time and their activity All the above immobilized biocatalysts remained active and the coagulation time was ranged from 90 to 480, 120-480, 330-510, and 270-540 min for (1), (2), (3), and (4) respectively. The quality of the cheese was examined through the determination of volatile compounds by SPME GC/MS analysis. These results encouraged us to study a continuous coagulation system of milk. Even though the (1) immobilized biocatalyst gave lower coagulation time, we used the (2) immobilized biocatalyst in the continuous system. The results were promising.Keywords: tubular cellulose, starch gel, composite biocatalyst, Rennin, milk coagulation
Procedia PDF Downloads 326114 Leachate Discharges: Review Treatment Techniques
Authors: Abdelkader Anouzla, Soukaina Bouaouda, Roukaya Bouyakhsass, Salah Souabi, Abdeslam Taleb
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During storage and under the combined action of rainwater and natural fermentation, these wastes produce over 800.000 m3 of landfill leachates. Due to population growth and changing global economic activities, the amount of waste constantly generated increases, making more significant volumes of leachate. Leachate, when leaching into the soil, can negatively impact soil, surface water, groundwater, and the overall environment and human life. The leachate must first be treated because of its high pollutant load before being released into the environment. This article reviews the different leachate treatments in September 2022 techniques. Different techniques can be used for this purpose, such as biological, physical-chemical, and membrane methods. Young leachate is biodegradable; in contrast, these biological processes lose their effectiveness with leachate aging. They are characterized by high ammonia nitrogen concentrations that inhibit their activity. Most physical-chemical treatments serve as pre-treatment or post-treatment to complement conventional treatment processes or remove specific contaminants. After the introduction, the different types of pollutants present in leachates and their impacts have been made, followed by a discussion highlighting the advantages and disadvantages of the various treatments, whether biological, physicochemical, or membrane. From this work, due to their simplicity and reasonable cost compared to other treatment procedures, biological treatments offer the most suitable alternative to limit the effects produced by the pollutants in landfill leachates.Keywords: landfill leachate, landfill pollution, impact, wastewater
Procedia PDF Downloads 89113 Impact of a Locally-Prepared Fermented Alcoholic Beverage from Jaggery on the Gut Bacterial Profile of the Tea-Tribal Populations of Assam, India
Authors: Rupamoni Thakur, Madhusmita Dehingia, Narayan C. Talukdar, Mojibur R. Khan
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The human gut is an extremely active fermentation site and is inhabited by diverse bacterial species. Consumption of alcoholic beverages has been shown to substantially modulate the human gut bacterial profile (GBP) of an individual. Assam, a major north-eastern state of India, is home to a number of tribal populations of which the tea-tribes form a major community. These tea-tribal communities are known to prepare and consume a locally-prepared alcoholic beverage from fermented jaggery, whose chemical composition is unknown. In this study, we demonstrate the effect of daily intake of the locally-prepared alcoholic beverage on the GBP of the tea-tribal communities and correlate it with the changes in the biochemical biomarkers of the population. The fecal bacterial diversity of 40 drinkers and 35 non-drinking healthy individuals were analyzed by polymerase chain reaction (PCR)–denaturing gradient gel electrophoresis (DGGE). The results suggested that the GBP was significantly modulated in the fermented-beverage consuming subjects. Significant difference was also observed in the serum biochemical parameters such as triglyceride, total cholesterol and the liver marker enzymes (ASAT/ALAT and GGT). Further studies to identify the GBP of drinkers vs non-drinkers through Next-generation Sequencing (NGS) analysis and to correlate the changes with the biochemical biomarkers of the population is underway.Keywords: alcoholic beverage, gut bacterial profile, PCR-DGGE analysis, tea-tribes of India
Procedia PDF Downloads 327112 Improvement Anaerobic Digestion Performance of Sewage Sludge by Co-Digestion with Cattle Manure
Authors: Raouf Hassan
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Biogas energy production from sewage sludge is an economically feasible and eco-friendly in nature. Sewage sludge is considered nutrient-rich substrates, but had lower values of carbone which consider an energy source for anaerobic bacteria. The lack or lower values of carbone-to-nitrogen ratio (C/N) reduced biogas yield and fermentation rate. Anaerobic co-digestion of sewage sludge offers several benefits over mono-digestion such as optimize nutrient balance, increased cost-efficiency and increased degradation rate. The high produced amounts of animal manures, which reach up to 90% of the total collected organic wastes, are recommended for the co-digestion with sewage sludge, especially with the limitations of industrial substrates. Moreover, cattle manures had high methane production potential (500 m3/t vsadded). When mixed with sewage sludge the potential methane production increased with increasing cattle manure content. In this paper, the effect of cattle manure (CM) addition as co-substrates on the sewage sludge (SS) anaerobic digestion performance was investigated under mesophilic conditions (35°C) using anaerobic batch reactors. The batch reactors were operated with a working volume 0.8 liter, and a hydraulic retention time of 30 days. The research work focus on studying two main parameters; the biogas yield (expressed as VSS) and pH values inside the reactors.Keywords: anaerobic digestion, sewage sludge, cattle manure, mesophilic, biogas yield, pH
Procedia PDF Downloads 315111 Efficiency of Natural Metabolites on Quality Milk Production in Mixed Breed Cows.
Authors: Mariam Azam, Sajjad Ur Rahman, Mukarram Bashir, Muhammad Tahir, Seemal Javaid, Jawad, Aoun Muhammad, Muhammad Zohaib, Hannan Khan
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Products of microbial origin are of great importance as they have proved their value in healthcare and nutrition, use of these microbial metabolites acquired from partially fermented soya hulls and wheat bran along with Saccharomyces cerevisiae (DL-22 S/N) substantiates to be a great source for an increase in the total milk production and quality yield.1×109 CFU/ml cells of Saccharomyces cerevisiae (DL-22 S/N) were further grown under in-vivo conditions for the assessment of quality milk production. Two groups with twelve cows, each having the same physical characteristics (Group A and Group B), were under study, Group A was daily fed with 12gm of biological metabolites and 22% protein-pelleted feed. On the other hand, the animals of Group B were provided with no metabolites in their feed. In thirty days of trial, improvement in the overall health, body score, milk protein, milk fat, yield, incidence rate of mastitis, ash, and solid not fat (SNF) was observed. The collected data showed that the average quality milk production was elevated up to 0.45 liter/h/d. However, a reduction in the milk fats up to 0.45% and uplift in the SNF value up to 0.53% of cow milk was also observed. At the same time, the incidence rate of mastitis recorded for the animals under trial was reduced to half, and improved non specific immunity was reported.Keywords: microbial metabolites, post-biotics, animal supplements, animal nutrition, proteins, animal production, fermentation
Procedia PDF Downloads 101110 Anti Staphylococcus aureus and Methicillin Resistant Staphylococcus aureus Action of Thermophilic Fungi Acrophialophora levis IBSD19 and Determination of Its Mode of Action Using Electron Microscopy
Authors: Shivankar Agrawal, Indira Sarangthem
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Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus (MRSA) remains one of the major causes of healthcare-associated and community-onset infections worldwide. Hence the search for non-toxic natural compounds having antibacterial activity has intensified for future drug development. The exploration of less studied niches of Earth can highly increase the possibility to discover novel bioactive compounds. Therefore, in this study, the cultivable fraction of fungi from the sediments of natural hot springs has been studied to mine potential fungal candidates with antibacterial activity against the human pathogen Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus. We isolated diverse strains of thermophilic fungi from a collection of samples from sediment. Following a standard method, we isolated a promising thermophilic fungus strain IBSD19, identified as Acrophialophora levis, possessing the potential to produce an anti-Staphylococcus aureus agent. The growth conditions were optimized and scaled to fermentation, and its produced extract was subjected to chemical extraction. The ethyl acetate fraction was found to display significant activity against Staphylococcus aureus and MRSA with a minimum inhibitory concentration (MIC) of 0.5 mg/ml and 4 mg/ml, respectively. The cell membrane integrity assay and SEM suggested that the fungal metabolites cause bacteria clustering and further lysis of the cell.Keywords: antibacterial activity, antioxidant, fungi, Staphylococcus aureus, MRSA, thermophiles
Procedia PDF Downloads 134109 Fermented Unripe Plantain (Musa paradisiacal) Peel Meal as a Replacement for Maize in the Diet of Nile Tilapia (Oreochromis niloticus) Fingerlings
Authors: N. A. Bamidele, S. O. Obasa, I. O. Taiwo, I. Abdulraheem, O. C. Odebiyi, A. A. Adeoye, O. E. Babalola, O. V. Uzamere
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A feeding trial was conducted to investigate the effect of fermented unripe plantain peel meal (FUP) on growth performance, nutrients digestibility and economic indices of production of Nile tilapia, Oreochromis niloticus fingerlings. Fingerlings (150) of Nile tilapia (1.70±0.1g) were stocked at 10 per plastic tank. Five iso-nitrogenous diets containing 40% crude protein in which maize meal was replaced by fermented unripe plantain peel meal at 0% (FUP0), 25% (FUP25), 50% (FUP50), 75% (FUP75) and 100% (FUP100) were formulated and prepared. The fingerlings were fed at 5% body weight per day for 56 days. There was no significant difference (p > 0.05) in all the growth parameters among the treatments. Feed conversion ratio of 1.35 in fish fed diet FUP25 was not significantly different (P > 0.05) from 1.42 of fish fed diet FUP0. Apparent protein digestibility of 86.94% in fish fed diet FUP100 was significantly higher (p < 0.05) than 70.37% in fish fed diet FUP0 while apparent carbohydrate of 88.34% in fish fed diet FUP0 was significantly different (p < 0.05) from 70.29% of FUP100. Red blood cell (4.30 ml/mm3) of fish fed diet FUP100 was not significantly different from 4.13 ml/mm3 of fish fed diet FUP50. The highest percentage profit of 88.85% in fish fed diet FUP100 was significantly higher than 66.68% in fish fed diet FUP0 while the profit index of 1.89 in fish fed diet FUP100 was significantly different from 1.67 in fish fed diet FUP0. Therefore, fermented unripe plantain peel meal can completely replace maize in the diet of O. niloticus fingerlings.Keywords: fermentation, fish diets, plantain peel, tilapia
Procedia PDF Downloads 537108 The Effect of Total Mixture Concentrate Based on Tofu Waste Silage as Feed on Performance of Lambs
Authors: Yafri Hazbi, Zaenal Bachruddin, Nafiatul Umami, Lies Mira Yusiati
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The objective of this study was to identify the benefits of total mixture concentrate based on tofu waste silage (TMC-TWS) as ration containing lactic acid bacteria on performance of lambs. Fifteen weaning lambs (2-3 months old) were randomly divided into two treatment groups, treatment group I (TI) was fed with TMC-TWS as ration and treatment group II (TII) was fed with TMC-TWS fresh (without silage fermentation). The performance of lambs was evaluated on day 0, 15, and 30 to have data of body weight per day. Meanwhile, blood sampling and feces were made on the 30th day to get an analysis on the blood profile (erythrocytes (mill/ml), hemoglobin (g/dL), packed cell volume (%), and leukocytes (mill/ml)) and the number of worm eggs in feces. The results of this study showed no significant difference between the effect of different feed on the blood profile (erythrocytes (mill/ml), hemoglobin (g/dL), packed cell volume (%), as well as the number of worm eggs in the feces. However the results showed significant differences if it is low (P<0.05) due to the treatment group based on sex on body weight gain per day, feed conversion rate and the number of erythrocytes.Keywords: lambs, total mixture concentrate, silage, acid lactid bacteria, blood profile, eggs worm in feces
Procedia PDF Downloads 178107 Utilization of Mango (Mangifera Indica) Seeds as an Organic Liquid Fertilizer in Bok-Choy (Brassica Rapa)
Authors: Bryan Emmanuel B. Marcelo, Frances Laura C. Galvez, Cyra Aleera T. Asanza, Ava Venice P. Garin
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The present study experimented with the utilization of mango (Mangifera indica) seeds as a fertilizer in the hydroponic farming of Bok Choy. The seeds were dried, mixed with EM Bokashi, and fermented for 14 days. The solution was then diluted into several ratios or concentrations: 25%: 1 part mango seed solution, 3 parts water; 50%: 2 parts mango seed solution, 2 parts water; 75%: 3 parts mango seed solution, 1 part water. 5 cups of soil with Bok Choy seeds were each planted in different containers for different concentrations of fertilizer. The fermentation of the nutrient solution lasted exactly 14 days and was directly brought to the lab for nutrient analysis and testing. In the data presented by the researchers in a span of 14 days, the study assessed varied mango seed fertilizer concentrations on Bok Choy growth. Despite an acidic pH (4.19) and moderate electrical conductivity, the 75% concentration yielded the highest growth (2.1cm) over 14 days, followed by 50%, 0, and 25%. Leaf count was consistently highest at 75%, and the leaf color remained #8CAA50 across concentrations. This emphasizes the importance of precise fertilizer application, with the 75% concentration showing optimal growth, the highest leaf count, and prevention of leaf withering until Day 14. Overall, these findings contribute to understanding bok choy’s adaptability and responses to different nutrient conditions.Keywords: dilution ratios, organic liquid fertilizer, hydroponic farming, growth asssessment
Procedia PDF Downloads 50106 Enzymatic Saccharification of Dilute Alkaline Pre-treated Microalgal (Tetraselmis suecica) Biomass for Biobutanol Production
Authors: M. A. Kassim, R. Potumarthi, A. Tanksale, S. C. Srivatsa, S. Bhattacharya
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Enzymatic saccharification of biomass for reducing sugar production is one of the crucial processes in biofuel production through biochemical conversion. In this study, enzymatic saccharification of dilute potassium hydroxide (KOH) pre-treated Tetraselmis suecica biomass was carried out by using cellulase enzyme obtained from Trichoderma longibrachiatum. Initially, the pre-treatment conditions were optimised by changing alkali reagent concentration, retention time for reaction, and temperature. The T. suecica biomass after pre-treatment was also characterized using Fourier Transform Infrared Spectra and Scanning Electron Microscope. These analyses revealed that the functional group such as acetyl and hydroxyl groups, structure and surface of T. suecica biomass were changed through pre-treatment, which is favourable for enzymatic saccharification process. Comparison of enzymatic saccharification of untreated and pre-treated microalgal biomass indicated that higher level of reducing sugar can be obtained from pre-treated T. suecica. Enzymatic saccharification of pre-treated T. suecica biomass was optimised by changing temperature, pH, and enzyme concentration to solid ratio ([E]/[S]). Highest conversion of carbohydrate into reducing sugar of 95% amounted to reducing sugar yield of 20 (wt%) from pre-treated T. suecica was obtained from saccharification, at temperature: 40°C, pH: 4.5 and [E]/[S] of 0.1 after 72 h of incubation. Hydrolysate obtained from enzymatic saccharification of pretreated T. suecica biomass was further fermented into biobutanol using Clostridium saccharoperbutyliticum as biocatalyst. The results from this study demonstrate a positive prospect of application of dilute alkaline pre-treatment to enhance enzymatic saccharification and biobutanol production from microalgal biomass.Keywords: microalgal biomass, enzymatic saccharification, biobutanol, fermentation
Procedia PDF Downloads 385105 Second Generation Biofuels: A Futuristic Green Deal for Lignocellulosic Waste
Authors: Nivedita Sharma
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The global demand for fossil fuels is very high, but their use is not sustainable since its reserves are declining. Additionally, fossil fuels are responsible for the accumulation of greenhouse gases. The emission of greenhouse gases from the transport sector can be reduced by substituting fossil fuels by biofuels. Thus, renewable fuels capable of sequestering carbon dioxide are in high demand. Second‐generation biofuels, which require lignocellulosic biomass as a substrate and ultimately producing ethanol, fall largely in this category. Bioethanol is a favorable and near carbon-neutral renewable biofuel leading to reduction in tailpipe pollutant emission and improving the ambient air quality. Lignocellulose consists of three main components: cellulose, hemicellulose and lignin which can be converted to ethanol with the help of microbial enzymes. Enzymatic hydrolysis of lignocellulosic biomass in 1st step is considered as the most efficient and least polluting methods for generating fermentable hexose and pentose sugars which subsequently are fermented to power alcohol by yeasts in 2nd step of the process. In the present technology, a complete bioconversion process i.e. potential hydrolytic enzymes i.e. cellulase and xylanase producing microorganisms have been isolated from different niches, screened for enzyme production, identified using phenotyping and genotyping, enzyme production, purification and application of enzymes for saccharification of different lignocellulosic biomass followed by fermentation of hydrolysate to ethanol with high yield is to be presented in detail.Keywords: cellulase, xylanase, lignocellulose, bioethanol, microbial enzymes
Procedia PDF Downloads 98104 Production of Soy Yoghurt Using Soymilk-Based Lactic Acid Bacteria as Starter Culture
Authors: Ayobami Solomon Popoola, Victor N. Enujiugha
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Production of soy-yogurt by fermentation of soymilk with lactic acid bacteria isolated from soymilk was studied. Soymilk was extracted from dehulled soybean seeds and pasteurized at 95 °C for 15 min. The soymilk was left to naturally ferment (temperature 40 °C; time 8 h) and lactic acid bacteria were isolated, screened and selected for yogurt production. Freshly prepared soymilk was pasteurized (95 °C, 15 min), inoculated with the lactic acid bacteria isolated (3% w/v starter culture) and incubated at 40 °C for 8 h. The yogurt produced was stored at 4 °C. Investigations were carried out with the aim of improving the sensory qualities and acceptability of soy yogurt. Commercial yogurt was used as a control. The percentage of soymilk inoculated was 70% of the broth. Soy-yoghurt samples produced were subsequently subjected to biochemical and microbiological assays which included total viable counts of fresh milk and soy-based yoghurt; proximate composition of functional soy-based yoghurt fermented with Lactobacillus plantarum; changes in pH, Titratable acidity, and lactic acid bacteria during a 14 day period of storage; as well as morphological and biochemical characteristics of lactic acid bacteria isolated. The results demonstrated that using Lactobacillus plantarum to inoculate soy milk for yogurt production takes about 8 h. The overall acceptability of the soy-based yogurt produced was not significantly different from that of the control sample. The use of isolate from soymilk had the added advantage of reducing the cost of yogurt starter culture, thereby making soy-yogurt, a good source of much desired good quality protein. However, more experiments are needed to improve the sensory qualities such as beany or astringent flavor and color.Keywords: soy, soymilk, yoghurt, starter culture
Procedia PDF Downloads 263103 Polyhydroxybutyrate Production in Bacteria Isolated from Estuaries along the Eastern Coast of India
Authors: Shubhashree Mahalik, Dhanesh Kumar, Jatin Kumar Pradhan
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Odisha is one of the coastal states situated on the eastern part of India with 480 km long coastline. The coastal Odisha is referred to as "Gift of Six Rivers". Balasore, a major coastal district of Odisha is bounded by Bay of Bengal in the East having 26 km long seashore. It is lined with several estuaries rich in biodiversity.Several studies have been carried out on the macro flora and fauna of this area but very few documented information are available regarding microbial biodiversity. In the present study, an attempt has been made to isolate and identify bacteria found along the estuaries of Balasore.Many marine microorganisms are sources of natural products which makes them potential industrial organisms. So the ability of the isolated bacteria to secrete one such industrially significant product, PHB (Polyhydroxybutyrate) has been elucidated. Several rounds of sampling, pure culture, morphological, biochemical and phylogenetic screening led to the identification of two PHB producing strains. Isolate 5 was identified to be Brevibacillus sp. and has maximum similarity to Brevibacillus parabrevis (KX83268). The isolate was named as Brevibacillus sp.KEI-5. Isolate 8 was identified asLysinibacillus sp. having closest similarity withLysinibacillus boroni-tolerance (KP314269) and named as Lysinibacillus sp. KEI-8.Media, temperature, carbon, nitrogen and salinity requirement were optimized for both isolates. Submerged fermentation of both isolates in Terrific Broth media supplemented with optimized carbon and nitrogen source at 37°C led to significant accumulation of PHB as detected by colorimetric method.Keywords: Bacillus, estuary, marine, Odisha, polyhydroxy butyrate
Procedia PDF Downloads 349102 Bioethanol Production from Wild Sorghum (Sorghum arundinacieum) and Spear Grass (Heteropogon contortus)
Authors: Adeyinka Adesanya, Isaac Bamgboye
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There is a growing need to develop the processes to produce renewable fuels and chemicals due to the economic, political, and environmental concerns associated with fossil fuels. Lignocellulosic biomass is an excellent renewable feedstock because it is both abundant and inexpensive. This project aims at producing bioethanol from lignocellulosic plants (Sorghum Arundinacieum and Heteropogon Contortus) by biochemical means, computing the energy audit of the process and determining the fuel properties of the produced ethanol. Acid pretreatment (0.5% H2SO4 solution) and enzymatic hydrolysis (using malted barley as enzyme source) were employed. The ethanol yield of wild sorghum was found to be 20% while that of spear grass was 15%. The fuel properties of the bioethanol from wild sorghum are 1.227 centipoise for viscosity, 1.10 g/cm3 for density, 0.90 for specific gravity, 78 °C for boiling point and the cloud point was found to be below -30 °C. That of spear grass was 1.206 centipoise for viscosity, 0.93 g/cm3 for density 1.08 specific gravity, 78 °C for boiling point and the cloud point was also found to be below -30 °C. The energy audit shows that about 64 % of the total energy was used up during pretreatment, while product recovery which was done manually demanded about 31 % of the total energy. Enzymatic hydrolysis, fermentation, and distillation total energy input were 1.95 %, 1.49 % and 1.04 % respectively, the alcoholometric strength of bioethanol from wild sorghum was found to be 47 % and the alcoholometric strength of bioethanol from spear grass was 72 %. Also, the energy efficiency of the bioethanol production for both grasses was 3.85 %.Keywords: lignocellulosic biomass, wild sorghum, spear grass, biochemical conversion
Procedia PDF Downloads 236101 Influence of Yeast Strains on Microbiological Stability of Wheat Bread
Authors: E. Soboleva, E. Sergachyova, S. G. Davydenko, T. V. Meledina
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Problem of food preservation is extremely important for mankind. Viscous damage ("illness") of bread results from development of Bacillus spp. bacteria. High temperature resistant spores of this microorganism are steady against 120°C) and remain in bread during pastries, potentially causing spoilage of the final product. Scientists are interested in further characterization of bread spoiling Bacillus spp. species. Our aim was to find weather yeast Saccharomyces cerevisiae strains that are able to produce natural antimicrobial killer factor can preserve bread illness. By diffusion method, we showed yeast antagonistic activity against spore-forming bacteria. Experimental technological parameters were the same as for bakers' yeasts production on the industrial scale. Risograph test during dough fermentation demonstrated gas production. The major finding of the study was a clear indication of the presence of killer yeast strain antagonistic activity against rope in bread causing bacteria. After demonstrating antagonistic effect of S. cerevisiae on bacteria using solid nutrient medium, we tested baked bread under provocative conditions. We also measured formation of carbon dioxide in the dough, dough-making duration and quality of the final products, when using different strains of S. cerevisiae. It is determined that the use of yeast S. cerevisiae RCAM 01730 killer strain inhibits appearance of rope in bread. Thus, natural yeast antimicrobial killer toxin, produced by some S. cerevisiae strains is an anti-rope in bread protector.Keywords: bakers' yeasts, killer toxin, rope in bread, Saccharomyces cerevisiæ
Procedia PDF Downloads 235100 Life Cycle Assessment Comparison between Methanol and Ethanol Feedstock for the Biodiesel from Soybean Oil
Authors: Pawit Tangviroon, Apichit Svang-Ariyaskul
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As the limited availability of petroleum-based fuel has been a major concern, biodiesel is one of the most attractive alternative fuels because it is renewable and it also has advantages over the conventional petroleum-base diesel. At Present, productions of biodiesel generally perform by transesterification of vegetable oils with low molecular weight alcohol, mainly methanol, using chemical catalysts. Methanol is petrochemical product that makes biodiesel producing from methanol to be not pure renewable energy source. Therefore, ethanol as a product produced by fermentation processes. It appears as a potential feed stock that makes biodiesel to be pure renewable alternative fuel. The research is conducted based on two biodiesel production processes by reacting soybean oils with methanol and ethanol. Life cycle assessment was carried out in order to evaluate the environmental impacts and to identify the process alternative. Nine mid-point impact categories are investigated. The results indicate that better performance on Abiotic Depletion Potential (ADP) and Acidification Potential (AP) are observed in biodiesel production from methanol when compared with biodiesel production from ethanol due to less energy consumption during the production processes. Except for ADP and AP, using methanol as feed stock does not show any advantages over biodiesel from ethanol. The single score method is also included in this study in order to identify the best option between two processes of biodiesel production. The global normalization and weighting factor based on eco-taxes are used and it shows that producing biodiesel form ethanol has less environmental load compare to biodiesel from methanol.Keywords: biodiesel, ethanol, life cycle assessment, methanol, soybean oil
Procedia PDF Downloads 22499 Bio Ethanol Production From the Co-Mixture of Jatropha Carcus L. Kernel Cake and Rice Straw
Authors: Felix U. Asoiro, Daniel I. Eleazar, Peter O. Offor
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As a result of increasing energy demands, research in bioethanol has increased in recent years all through the world, in abide to partially or totally replace renewable energy supplies. The first and third generation feedstocks used for biofuel production have fundamental drawbacks. Waste rice straw and cake from second generation feedstock like Jatropha curcas l. kernel (JC) is seen as non-food feedstock and promising candidates for the industrial production of bioethanol. In this study, JC and rice husk (RH) wastes were characterized for proximate composition. Bioethanol was produced from the residual polysaccharides present in rice husk (RH) and Jatropha seed cake by sequential hydrolytic and fermentative processes at varying mixing proportions (50 g JC/50 g RH, 100 g JC/10 g RH, 100 g JC/20 g RH, 100 g JC/50 g RH, 100 g JC/100 g RH, 100 g JC/200 g RH and 200 g JC/100 g RH) and particle sizes (0.25, 0.5 and 1.00 mm). Mixing proportions and particle size significantly affected both bioethanol yield and some bioethanol properties. Bioethanol yield (%) increased with an increase in particle size. The highest bioethanol (8.67%) was produced at a mixing proportion of 100 g JC/50g RH at 0.25 mm particle size. The bioethanol had the lowest values of specific gravity and density of 1.25 and 0.92 g cm-3 and the highest values of 1.57 and 0.97 g cm-3 respectively. The highest values of viscosity (4.64 cSt) were obtained with 200 g JC/100 g RH, at 1.00 mm particle size. The maximum flash point and cloud point values were 139.9 oC and 23.7oC (100 g JC/200 g RH) at 1 mm and 0.5 mm particle sizes respectively. The maximum pour point value recorded was 3.85oC (100 g JC/50 g RH) at 1 mm particle size. The paper concludes that bioethanol can be recovered from JC and RH wastes. JC and RH blending proportions as well as particle sizes are important factors in bioethanol production.Keywords: bioethanol, hydrolysis, Jatropha curcas l. kernel, rice husk, fermentation, proximate composition
Procedia PDF Downloads 9698 Effect of Biostimulants on Downstream Processing of Endophytic Fungi Hosted in Aromatic Plant, Ocimum basicilium
Authors: Kanika Chowdhary, Satyawati Sharma
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Endophytic microbes are hosted inside plants in a symbiotic and hugely benefitting relationship. Exploring agriculturally beneficial endophytes is quite a prospective field of research. In the present work fungal endophytes associated with aromatic plant Ocimum basicilium L. were investigated for biocontrol potential. The anti-plant pathogenic activity of fungal endophytes was tested against causal agent of stem rot Sclerotinia sclerotiorum. 75 endophytic fungi were recovered through culture-dependent approach. Fungal identification was performed both microscopically and by rDNA ITS sequencing. Curvuaria lunata (Sb-6) and Colletotrichum lindemuthianum (Sb-8) inhibited 86% and 72% mycelia growth of S. sclerotinia on Sabouraud dextrose agar medium at 7.4 pH. Small-scale fermentation was carried out on sterilised oatmeal grain medium. In another set of experiment, fungi were grown in oatmeal grain medium amended with certain biostimulants such as aqueous seaweed extract (10% v/w); methanolic seaweed extract (5% v/w); cow urine (20% v/w); biochar (10% w/w) in triplicate along with control of each to ascertain the degree of metabolic difference and anti-plant pathogenic activity induced. Phytochemically extracts of both the fungal isolates showed the presence of flavanoids, phenols, tannins, alkaloids and terpenoids. Ethylacetate extract of C. lunata and C. lindemuthianum suppressed S. sclerotinia conidial germination at IC50 values of 0.514± 0.02 and 0.913± 0.04 mg/ml. Therefore, fungal endophytes of O. basicilium are highly promising bio-resource agent, which can be developed further for sustainable agriculture.Keywords: endophytic fungi, ocimum basicilium, sclerotinia sclerotiorum, biostimulants
Procedia PDF Downloads 17697 Deciphering Electrochemical and Optical Properties of Folic Acid for the Applications of Tissue Engineering and Biofuel Cell
Authors: Sharda Nara, Bansi Dhar Malhotra
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Investigation of the vitamins as an electron transfer mediator could significantly assist in merging the area of tissue engineering and electronics required for the implantable therapeutic devices. The present study report that the molecules of folic acid released by Providencia rettgeri via fermentation route under the anoxic condition of the microbial fuel cell (MFC) exhibit characteristic electrochemical and optical properties, as indicated by absorption spectroscopy, photoluminescence (PL), and cyclic voltammetry studies. The absorption spectroscopy has depicted an absorption peak at 263 nm with a small bulge around 293 nm on day two of bacterial culture, whereas an additional peak was observed at 365 nm on the twentieth day. Furthermore, the PL spectra has indicated that the maximum emission occurred at various wavelengths 420, 425, 440, and 445 nm when excited by 310, 325, 350, and 365 nm. The change of emission spectra with varying excitation wavelength might be indicating the presence of tunable optical bands in the folic acid molecules co-related with the redox activity of the molecules. The results of cyclic voltammetry studies revealed that the oxidation and reduction occurred at 0.25V and 0.12V, respectively, indicating the electrochemical behavior of the folic acid. This could be inferred that the released folic acid molecules in a MFC might undergo inter as well as intra molecular electron transfer forming different intermediate states while transferring electrons to the electrode surface. Synchronization of electrochemical and optical properties of folic acid molecules could be potentially promising for the designing of electroactive scaffold and biocompatible conductive surface for the applications of tissue engineering and biofuel cells, respectively.Keywords: biofuel cell, electroactivity, folic acid, tissue engineering
Procedia PDF Downloads 13196 Preparation and Functional Properties of Synbiotic Yogurt Fermented with Lactobacillus brevis PML1 Derived from a Fermented Cereal-Dairy Product
Authors: Farideh Tabatabei-Yazdi, Fereshteh Falah, Alireza Vasiee
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Nowadays, production of functional foods has become very essential. Inulin is one of the most functional hydrocolloid compounds used in such products. In the present study, the production of a synbiotic yogurt containing 1, 2.5, and 5% (w/v) inulin has been investigated. The yogurt was fermented with Lactobacillus brevis PML1 derived from Tarkhineh, an Iranian cereal-dairy fermented food. Furthermore, the physicochemical properties, antioxidant activity, sensory attributes, and microbial viability properties were investigated on the 0th, 7th, and 14th days of storage after fermentation. The viable cells of L. brevis PML1 reached 108 CFU/g, and the product resisted to simulated digestive juices. Moreover, the synbiotic yogurt impressively increased the production of antimicrobial compounds and had the most profound antimicrobial effect on S. typhimurium. The physiochemical properties were in the normal range, and the fat content of the synbiotic yogurt was reduced remarkably. The antioxidant capacity of the fermented yogurt was significantly increased (p<0:05), which was equal to those of DPPH (69:18±1:00%) and BHA (89:16±2:00%). The viability of L. brevis PML1 was increased during storage. Sensory analysis showed that there were significant differences in terms of the impressive parameters between the samples and the control (p<0:05). Addition of 2.5% inulin not only improved the physical properties but also retained the viability of the probiotic after 14 days of storage, in addition to the viability of L. brevis with a viability count above 6 log CFU/g in the yogurt. Therefore, a novel synbiotic product containing L. brevis PML1, which can exert the desired properties, can be used as a suitable carrier for the delivery of the probiotic strain, exerting its beneficial health effects.Keywords: functional food, lactobacillus brevis, symbiotic yogurt, physiochemical properties
Procedia PDF Downloads 9195 Isolation and Identification of Probiotic Lactic Acid Bacteria with Cholesterol Lowering Potential and Their Use in Fermented Milk Product
Authors: Preeyarach Whisetkhan, Malai Taweechotipatr, Ulisa Pachekrepapol
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Elevated level of blood cholesterol or hypercholesterolemia may lead to atherosclerosis and poses a major risk for cardiovascular diseases. Probiotics play a crucial role in human health, and probiotic bacteria that possesses bile salt hydrolase (BSH) activity can be used to lower cholesterol level of the host. The aim of this study was to investigate whether lactic acid bacteria (LAB) isolated from traditional Thai fermented foods were able to exhibit bile salt hydrolase activity and their use in fermented milk. A total of 28 isolates were tested for BSH activity by plate method on MRS agar supplemented with 0.5% sodium salt of taurodeoxycholic acid and incubated at 37°C for 48 h under anaerobic condition. The results showed that FN1-1 and FN23-3 isolates possessed strong BSH activity. FN1-1 and FN23-3 isolates were then identified for phenotype, biochemical characteristics, and genotype (16S rRNA sequencing). FN1-1 isolate showed 99.92% similarity to Lactobacillus pentosus DSM 20314(T), while FN23-3 isolate showed 99.94% similarity to Enterococcus faecium CGMCC1.2136 (T). Lactobacillus pentosus FN1-1 and Enterococcus faecium FN23-3 were tolerant of pH 3-4 and 0.3 and 0.8% bile. Bacterial count and pH of milk fermented with Lactobacillus pentosus FN1-1 at 37°C and 43°C were investigated. The results revealed that Lactobacillus pentosus FN1-1 was able to grow in milk, which led to decrease in pH level. Fermentation at 37°C resulted in faster growth rate than at 43 °C. Lactobacillus pentosus FN1-1 was a candidate probiotic to be used in fermented milk products to reduce the risk of high-cholesterol diseases.Keywords: probiotics, lactic acid bacteria, bile salt hydrolase, cholesterol
Procedia PDF Downloads 14994 Sex-Dependent Fitness Improvement of Hercules Beetle Larvae by Amendment of Thermophile-Fermented Compost to Humus
Authors: Futo Asano, Yusuke Yatsushiro, Hirokuni Miyamoto, Hiroaki Kodama
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A thermophile-fermented compost is produced using small fishes, crabs, and shrimps under a high temperature (approximately 75℃) by fermentation-associated self-heating. This compost has been used as a feed additive for pigs and hens in Japan, and the fecundity of this livestock is enhanced. Firmicutes is a dominant phylum in the microbial composition of the compost. We first reported that improvement of female larval fitness of Hercules beetle can be achieved by amendment of this compost to the humus. When the 90-d-old larvae were reared for subsequent 72 days in the humus with this compost, the growth of female larvae was significantly enhanced when compared with the growth of female larvae in the humus without the compost. In contrast, the growth of male larvae in the compost-free humus was the same as the larvae grow in the compost-amended humus. The bacterial composition of the feces of larvae was determined at 0 days and 46 days after transfer to the humus with or without the compost. The most dominant bacterium in the feces was Xylanimonas. Interestingly, the growth improvement of female larvae was associated with an increased abundance of Mollicutes in the fecal samples. These results indicate that the compost act as a probiotic material for enhancing the female larvae growth by supporting Mollicutes. Here, we tried to isolate Mollicutes from the contents of the midgut and hindgut of the 3rd instar female larvae of the Hercules beetle. These gut contents were spread onto a selective agar medium for Mollicutes (PPLO agar broth, BD Difco, NJ, USA). Although we isolated none of the Mollicutes until now, several bacteria that are closely related to Xylanimonas and Luteimicrobium were isolated. These isolates have xylanase and glucanase (CMCase) activities. We show the gut bacterial profiles of larvae and discuss how the fitness of female larvae of the Hercules beetle is improved by the compost.Keywords: compost, beetle, mollicutes, woody biomass
Procedia PDF Downloads 8493 Efficiency of Wood Vinegar Mixed with Some Plants Extract against the Housefly (Musca domestica L.)
Authors: U. Pangnakorn, S. Kanlaya
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The efficiency of wood vinegar mixed with each individual of three plants extract such as: citronella grass (Cymbopogon nardus), neem seed (Azadirachta indica A. Juss), and yam bean seed (Pachyrhizus erosus Urb.) were tested against the second instar larvae of housefly (Musca domestica L.). Steam distillation was used for extraction of the citronella grass while neem and yam bean were simple extracted by fermentation with ethyl alcohol. Toxicity test was evaluated in laboratory based on two methods of larvicidal bioassay: topical application method (contact poison) and feeding method (stomach poison). Larval mortality was observed daily and larval survivability was recorded until the survived larvae developed to pupae and adults. The study resulted that treatment of wood vinegar mixed with citronella grass showed the highest larval mortality by topical application method (50.0%) and by feeding method (80.0%). However, treatment of mixed wood vinegar and neem seed showed the longest pupal duration to 25 day and 32 days for topical application method and feeding method respectively. Additional, larval duration on treated M. domestica larvae was extended to 13 days for topical application method and 11 days for feeding method. Thus, the feeding method gave higher efficiency compared with the topical application method.Keywords: housefly (Musca domestica L.), neem seed (Azadirachta indica), citronella grass (Cymbopogon nardus), yam bean seed (Pachyrhizus erosus), mortality
Procedia PDF Downloads 34192 Levansucrase from Zymomonas Mobilis KIBGE-IB14: Production Optimization and Characterization for High Enzyme Yield
Authors: Sidra Shaheen, Nadir Naveed Siddiqui, Shah Ali Ul Qader
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In recent years, significant progress has been made in discovering and developing new bacterial polysaccharides producing organisms possessing extremely functional properties. Levan is a natural biopolymer of fructose which is produced by transfructosylation reaction in the presence of levansucrase. It is one of the industrially promising enzymes that offer a variety of industrial applications in the field of cosmetics, foods and pharmaceuticals. Although levan has significant applications but the yield of levan produced is not equal to other biopolymers due to the inefficiency of producer microorganism. Among wide range of levansucrase producing microorganisms, Zymomonas mobilis is considered as a potential candidate for large scale production of this natural polysaccharide. The present investigation is concerned with the isolation of levansucrase producing natural isolate having maximum enzyme production. Furthermore, production parameters were optimized to get higher enzyme yield. Levansucrase was partially purified and characterized to study its applicability on industrial scale. The results of this study revealed that the bacterial strain Z. mobilis KIBGE-IB14 was the best producer of levansucrase. Bacterial growth and enzyme production was greatly influenced by physical and chemical parameters. Maximum levansucrase production was achieved after 24 hours of fermentation at 30°C using modified medium of pH-6.5. Contrary to other levansucrases, the one presented in the current study is able to produce high amount of products in relatively short period of time with optimum temperature at 35°C. Due to these advantages, this enzyme can be used on large scale for commercial production of levan and other important metabolites.Keywords: levansucrase, metabolites, polysaccharides, transfructosylation
Procedia PDF Downloads 49791 Quantification and Identification of the Main Components of the Biomass of the Microalgae Scenedesmus SP. – Prospection of Molecules of Commercial Interest
Authors: Carolina V. Viegas, Monique Gonçalves, Gisel Chenard Diaz, Yordanka Reyes Cruz, Donato Alexandre Gomes Aranda
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To develop the massive cultivation of microalgae, it is necessary to isolate and characterize the species, improving genetic tools in search of specific characteristics. Therefore, the detection, identification and quantification of the compounds that compose the Scenedesmus sp. were prerequisites to verify the potential of these microalgae. The main objective of this work was to carry out the characterization of Scenedesmus sp. as to the content of ash, carbohydrates, proteins and lipids as well as the determination of the composition of their lipid classes and main fatty acids. The biomass of Scenedesmus sp, showed 15,29 ± 0,23 % of ash and CaO (36,17 %) was the main component of this fraction, The total protein and carbohydrate content of the biomass was 40,74 ± 1,01 % and 23,37 ± 0,95 %, respectively, proving to be a potential source of proteins as well as carbohydrates for the production of ethanol via fermentation, The lipid contents extracted via Bligh & Dyer and in situ saponification were 8,18 ± 0,13 % and 4,11 ± 0,11 %, respectively. In the lipid extracts obtained via Bligh & Dyer, approximately 50 % of the composition of this fraction consists of fatty compounds, while the other half is composed of an unsaponifiable fraction composed mainly of chlorophylls, phytosterols and carotenes. From the lowest yield, it was possible to obtain a selectivity of 92,14 % for fatty components (fatty acids and fatty esters) confirmed through the infrared spectroscopy technique. The presence of polyunsaturated acids (~45 %) in the lipid extracts indicated the potential of this fraction as a source of nutraceuticals. The results indicate that the biomass of Scenedesmus sp, can become a promising potential source for obtaining polyunsaturated fatty acids, carotenoids and proteins as well as the simultaneous obtainment of different compounds of high commercial value.Keywords: microalgae, Desmodesmus, lipid classes, fatty acid profile, proteins, carbohydrates
Procedia PDF Downloads 9790 Enhanced Production of Endo-β-1,4-Xylanase from a Newly Isolated Thermophile Geobacillus stearothermophilus KIBGE-IB29 for Prospective Industrial Applications
Authors: Zainab Bibi, Afsheen Aman, Shah Ali Ul Qader
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Endo-β-1,4-xylanases [EC 3.2.1.8] are one of the major groups of enzymes that are involved in degradation process of xylan and have several applications in food, textile and paper processing industries. Due to broad utility of endo-β-1,4-xylanase, researchers are focusing to increase the productivity of this hydrolase from various microbial species. Harsh industrial condition, faster reaction rate and efficient hydrolysis of xylan with low risk of contamination are critical requirements of industry that can be fulfilled by synthesizing the enzyme with efficient properties. In the current study, a newly isolated thermophile Geobacillus stearothermophilus KIBGE-IB29 was used in order to attain the maximum production of endo-1,4-β-xylanase. Bacterial culture was isolated from soil, collected around the blast furnace site of a steel processing mill, Karachi. Optimization of various nutritional and physical factors resulted the maximum synthesis of endo-1,4-β-xylanase from a thermophile. High production yield was achieved at 60°C and pH-6.0 after 24 hours of incubation period. Various nitrogen sources viz. peptone, yeast extract and meat extract improved the enzyme synthesis with 0.5%, 0.2% and 0.1% optimum concentrations. Dipotassium hydrogen phosphate (0.25%), potassium dihydrogen phosphate (0.05%), ammonium sulfate (0.05%) and calcium chloride (0.01%) were noticed as valuable salts to improve the production of enzyme. The thermophilic nature of isolate, with its broad pH stability profile and reduced fermentation time indicates its importance for effective xylan saccharification and for large scale production of endo-1,4-β-xylanase.Keywords: geobacillus, optimization, production, xylanase
Procedia PDF Downloads 30889 Some Extreme Halophilic Microorganisms Produce Extracellular Proteases with Long Lasting Tolerance to Ethanol Exposition
Authors: Cynthia G. Esquerre, Amparo Iris Zavaleta
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Extremophiles constitute a potentially valuable source of proteases for the development of biotechnological processes; however, the number of available studies in the literature is limited compared to mesophilic counterparts. Therefore, in this study, Peruvian halophilic microorganisms were characterized to select suitable proteolytic strains that produce active proteases under exigent conditions. Proteolysis was screened using the streak plate method with gelatin or skim milk as substrates. After that, proteolytic microorganisms were selected for phenotypic characterization and screened by a semi-quantitative proteolytic test using a modified method of diffusion agar. Finally, proteolysis was evaluated using partially purified extracts by ice-cold ethanol precipitation and dialysis. All analyses were carried out over a wide range of NaCl concentrations, pH, temperature and substrates. Of a total of 60 strains, 21 proteolytic strains were selected, of these 19 were extreme halophiles and 2 were moderates. Most proteolytic strains demonstrated differences in their biochemical patterns, particularly in sugar fermentation. A total of 14 microorganisms produced extracellular proteases, 13 were neutral, and one was alkaline showing activity up to pH 9.0. Proteases hydrolyzed gelatin as the most specific substrate. In general, catalytic activity was efficient under a wide range of NaCl (1 to 4 M NaCl), temperature (37 to 55 °C) and after an ethanol exposition performed at -20 °C for 24 hours. In conclusion, this study reported 14 candidates extremely halophiles producing extracellular proteases capable of being stable and active on a wide range of NaCl, temperature and even long lasting ethanol exposition.Keywords: biotechnological processes, ethanol exposition, extracellular proteases, extremophiles
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