Trapa Natans: Nature And Phytochemistry Of The "Submerged Leaves".

As the morphology of submerged leaves is variously interpreted, they are subjected to a detailed morphological, anatomical and phytochemical studies. The position of origin at the leaf base, pinnate tristichous nature of leaflets and the limited life span prove the submerged leaves to be leafy in nature. The absence of root cap and exarch protoxylem which are the typical characters of roots goes against the root-concept. The morphological similarities of young submerged floating leaves to the other submerged leaves, ultrastructural studies like cuticular combs and pore like structures as in floating leaves, phytochemical observations and molecular biological data indicate the submerged structures to be true leaves. The role of environmental factors in shaping the characters is suggested.

Modulating the production of xylanase by Bacillus pumilus BS131 through optimization using waste fiber sludge / Modulando a produção de xilanase por Bacillus pumilus BS131 por meio da otimização usando lodo de fibra residual

In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.

Nos últimos dias, a fonte alternativa de carbono mais barata para fins de fermentação é desejável para minimizar o custo de produção. As xilanases têm se tornado enzimas atraentes como seu potencial no biobranqueamento da indústria de papel e celulose. O objetivo do presente estudo foi identificar a capacidade potencial na produção de xilanase por Bacillus pumilus BS131 isolado localmente usando lodo de fibra residual e farelo de trigo em meio de fermentação submersa. As condições de crescimento da cultura foram otimizadas para obter uma quantidade significativa de xilanase. A produção máxima de xilanase foi registrada após 72 horas de incubação a 30 °C e pH 7 com concentração de substrato de 4,0%. Resumindo, a produção de xilanase usando lodo de fibra residual de baixo custo e farelo de trigo como uma alternativa no lugar do substrato de xilano caro foi mais econômica e ecológica.

Modulating the production of xylanase by Bacillus pumilus BS131 through optimization using waste fiber sludge

Abstract In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.

Resumo Nos últimos dias, a fonte alternativa de carbono mais barata para fins de fermentação é desejável para minimizar o custo de produção. As xilanases têm se tornado enzimas atraentes como seu potencial no biobranqueamento da indústria de papel e celulose. O objetivo do presente estudo foi identificar a capacidade potencial na produção de xilanase por Bacillus pumilus BS131 isolado localmente usando lodo de fibra residual e farelo de trigo em meio de fermentação submersa. As condições de crescimento da cultura foram otimizadas para obter uma quantidade significativa de xilanase. A produção máxima de xilanase foi registrada após 72 horas de incubação a 30 °C e pH 7 com concentração de substrato de 4,0%. Resumindo, a produção de xilanase usando lodo de fibra residual de baixo custo e farelo de trigo como uma alternativa no lugar do substrato de xilano caro foi mais econômica e ecológica.

Modulating the production of xylanase by Bacillus pumilus BS131 through optimization using waste fiber sludge / Modulando a produção de xilanase por Bacillus pumilus BS131 por meio da otimização usando lodo de fibra residual

Abstract In recent days, cheapest alternative carbon source for fermentation purpose is desirable to minimize production cost. Xylanases have become attractive enzymes as their potential in bio-bleaching of pulp and paper industry. The objective of the present study was to identify the potential ability on the xylanase production by locally isolated Bacillus pumilus BS131 by using waste fiber sludge and wheat bran media under submerged fermentation. Culture growth conditions were optimized to obtain significant amount of xylanase. Maximum xylanase production was recorded after 72 hours of incubation at 30 °C and 7 pH with 4.0% substrate concentration. In the nutshell, the production of xylanase using inexpensive waste fiber sludge and wheat-bran as an alternative in place of expensive xylan substrate was more cost effective and environment friendly.

Resumo Nos últimos dias, a fonte alternativa de carbono mais barata para fins de fermentação é desejável para minimizar o custo de produção. As xilanases têm se tornado enzimas atraentes como seu potencial no biobranqueamento da indústria de papel e celulose. O objetivo do presente estudo foi identificar a capacidade potencial na produção de xilanase por Bacillus pumilus BS131 isolado localmente usando lodo de fibra residual e farelo de trigo em meio de fermentação submersa. As condições de crescimento da cultura foram otimizadas para obter uma quantidade significativa de xilanase. A produção máxima de xilanase foi registrada após 72 horas de incubação a 30 °C e pH 7 com concentração de substrato de 4,0%. Resumindo, a produção de xilanase usando lodo de fibra residual de baixo custo e farelo de trigo como uma alternativa no lugar do substrato de xilano caro foi mais econômica e ecológica.

Molecular Characterization, Optimization and Production of PHA by Indigenous Bacteria Using Alternative Nutrient Sources as Substrate

Polyhydroxyalkanoates (PHA) are renewable, biodegradable biopolymer intracellularly accumulated by wide array of microorganisms as carbon reserve. This study investigates the influence of various cultural conditions on PHA production by a recently isolated local species under submerged fermentation. Six PHA producing strains were identified by 16S rDNA gene sequencing and strain Priestia flexa OWO1 showed satisfactory PHA productivity. The effects of production parameters were investigated and extraction of PHA was carried out using sodium hypochlorite method and maximum amount was detected after 72h. Maximum PHA production was obtained at incubation period of 48h, pH of 7.0 and temperature of 30oC. Amongst the hydrolysate of agro waste used, brewers spent grain (BSG) gave maximum yield of 3.01g/L while beans bran powder gave the highest PHA yields of 3.9 g/L amongst the organic nitrogen sources tested. Analysis of the crude PHA by Fourier Transform Infrared Spectroscopy (FT-IR) showed the presence of methyl, methylene as well as carbonyl functional groups. PHA production was higher after optimizing the production conditions as compared to basal medium therefore the utilization of these cheap renewable resources as alternative substrates for production of PHA make the process cost effective and sustainable.

The Influence of Agitation Rates, pH and Calcium Carbonate on L-lysine Production by Bacillus subtilis using Agricultural Products as Carbon and Nitrogen Sources

L-Lysine is an essential amino acid that is required in the diet of humans and animals. It is utilized in human medicine, cosmetics and pharmaceutical industry. ’The influence of agitation rates, pH and calcium carbonate on L-lysine production by Bacillus subtilis using agricultural products as carbon and nitrogen sources was studied. The L-lysine-producing bacteria had already been isolated from Nigerian soil. They were purified and Identified as B. subtilis PR13 and B. subtilis PR9, using cultural, biochemical and molecular characteristics. Optimization of some parameters which included agitation rates, pH values and CaCO3 concentrations, on L-lysine production by the Bacillus species was carried out. The L-lysine was produced in 250 ml flasks containing fermentation media (FM1 and FM2). The findings revealed that, enhanced L-lysine yield of 2.10 and 1.33 mg/ml was observed at agitation rate of 180 rpm for B. subtilis PR13 and PR9 respectively. There was a positive correlation between agitation rates and L- lysine production by B. subtilis PR13 and PR9 (r = 0.96 and 0.83 respectively). The pH of 7.5, stimulated optimum L- lysine yield of 2.27 mg/ml for PR13 and 1.38 mg/ml for PR9. There was a positive correlation between pH values and L-lysine production by B. subtilis PR13 and PR 9 (r = 0.63 and 0.50 respectively). The supplementation of 40g/l of CaCO3, enhanced optimum L-lysine yield of 2.18 mg/ml for B. subtilis PR 13 and 1.30 mg/ml for B. subtilis PR9. There was a positive correlation between varying concentrations of calcium carbonate and L-lysine production by the B. subtilis PR13 (r =0.35), while negative correlation was observed for B. subtilis PR 9 (r = -0.10). The results obtained in the study illustrated that the optimization of process parameters could increase the L-lysine yield from agricultural products by B. subtilis PR13 and B. subtilis PR9.

Protease Production by Submerged Fermentation in Shake Flasks Using Bacillus sp. Isolated from the Soil

Proteases are one of the most industrially important enzymes, which account for about 60% of total enzyme market. Protease production by submerged fermentation in shake flasks using Bacillus sp. isolated from the soil was studied. Soil samples were collected from different locations within Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra state. The soil samples were serially diluted and inoculated on sterilized skim milk agar plates. The plates were incubated at 30oC for 72 h. A clear zone around the colonies gave an indication of protease-producing bacteria isolates. The selected protease producers were subsequently used for shake flask fermentation in 50 ml sterile medium. Optimization study was conducted to determine the effect of carbon sources, nitrogen sources, trace elements, agitation rates and pH. Twenty one bacteria isolates were found to be active protease producers and isolates RS-5 and OS-9 had the highest zone of clearance of 13.5 and 12.1 mm respectively. The result of submerged production of protease by the bacteria isolates revealed that the isolates RS-5 and OS-9 accumulated maximum protease yield of 3.23 and 2.71 U/ml respectively. The isolates were Gram positive and endospore formers, and were identified as Bacillus sp. RS-5 and OS-9.The addition of Starch and maltose stimulated optimum protease production of 3.47 and 2.77 U/ml by Bacillus sp. RS-5 and OS-9 respectively. Beef extract enhanced maximum enzyme yield of 3.35 and 2.90 U/ml for Bacillus sp. RS-5 and OS-9 respectively. Maximum protease yield of 3.28 U/ml for Bacillus sp. RS-5 and 2.85 U/ml for Bacillus sp. OS-9 was obtained by the supplementation of 0.4 g/l of FeS04 respectively. The maximum protease yield was observed at agitation rate of 200 rpm for Bacillus sp. RS-5 and 170 rpm for Bacillus sp. OS-9. At pH8, protease accumulation was highest for Bacillus sp. RS-5 and OS-9. The study revealed that the soil harbours some protease-producing bacteria strains and protease production can be greatly enhanced through optimization of process parameters.

Do submerged roots hinder orthodontic treatment or the use of implants?

ABSTRACT Introduction: In clinical practice, submerged roots are found with high frequency, and their presence can change the planning of dental movements and implant placement. Objectives: To provide explanations of possible developments in the area involved, according to the evolutionary stage of the process, at the time of diagnosis. Discussion: After atrophy of the periodontal ligament and epithelial remnants of Malassez, ankylosis of the bone with the submerged root occurs, and initiates a process of replacement resorption. Until this process reaches the most advanced stage, this area represents an increased "bone" density, and if some care is not taken, this can generate resorption problems in the tooth to be moved. Whereas implants can be placed, despite the presence of the submerged root, irrespective of the stage of evolution. Conclusion: It is natural for the onset of alveolodental ankylosis and tooth replacement resorption to occur in submerged roots, and its stage of evolution will be decisive in the approach to be adopted in clinical planning.

RESUMO Introdução: A frequência, na prática clínica, das raízes submersas é elevada, e sua presença pode modificar o planejamento de movimentações osteodentárias e da instalação de implantes. Objetivo: Apresentar as explicações das possíveis evoluções na área envolvida, de acordo com o estágio evolutivo do processo, no momento do diagnóstico. Discussão: Depois da atrofia do ligamento periodontal e dos restos epiteliais de Malassez, o osso anquilosa-se com a raiz submersa, e se inicia a reabsorção por substituição. Até se chegar ao estágio mais avançado, essa área representa uma densidade "óssea" aumentada, o que pode gerar problemas reabsortivos no dente a ser movimentado, caso alguns cuidados não sejam tomados. Por outro lado, os implantes podem ser aplicados, apesar da presença da raiz submersa, independentemente da fase evolutiva. Conclusão: É natural que, em raízes submersas, se instale a anquilose alveolodentária e a reabsorção dentária por substituição, e o seu estágio evolutivo será determinante na conduta a ser adotada no planejamento clínico.

Reatores híbridos anaeróbio e aeróbio para remoção de matéria orgânica e nitrogênio em esgoto doméstico diluído / Hybrid anaerobic and aerobic reactors for organic matter and nitrogen removal in diluted domestic sewage

RESUMO A remoção de matéria orgânica e de nitrogênio em esgoto doméstico diluído foi avaliada em dois reatores híbridos, um anaeróbio (RHAN) e outro aeróbio (RHAE). O RHAN era formado por uma câmara tipo upflow anaerobic sludge blanket sobreposta por outra de filtro anaeróbio, enquanto o RHAE tinha uma câmara de lodo ativado sobreposta por outra de biofilme aerado submerso. A operação do sistema foi dividida em duas fases, FI e FII, com razões de recirculação de 50 e 75% e duração de 94 e 110 dias, respectivamente. Para a remoção de nitrogênio, o RHAE foi operado com oxigênio dissolvido de 3,0 mg.L-1. A técnica da reação em cadeia da polimerase foi empregada tanto para o lodo suspenso das câmaras inferiores, como para o biofilme aderido nas câmaras superiores, para identificar a presença de micro-organismos desnitrificantes e nitrificantes. As maiores eficiências de remoção em termos de demanda química de oxigênio e nitrogênio total foram obtidas em FII, sendo 91% e ~50%, respectivamente; as concentrações no efluente foram ~40 mg O2.L-1 e ~15 mg N-NT.L-1. A presença de três grupos de bactérias, as desnitrificantes, as oxidantes de amônia e as oxidantes de nitrito, foi confirmada no biofilme aderido do RHAE, indicando uma biomassa mixotrófica e sugerindo a possibilidade do processo de nitrificação e desnitrificação simultânea.

ABSTRACT The removal of organic matter and nitrogen in diluted domestic sewage was evaluated in two hybrid reactors, one anaerobic (ANHR) and another aerobic (AEHR). ANHR was formed by a upflow anaerobic sludge blanket (UASB)-type chamber overlaid by an anaerobic filter, while AEHR had an activated sludge chamber overlaid by a submerged aerated biofilm chamber. The experimental period was divided into two phases, FI and FII, with recirculation ratios of 50 and 75%, and duration of 94 and 110 days, respectively. For nitrogen removal, AEHR was operated with a 3.0-mg.L-1 dissolved oxygen. Polymerase chain reaction technique was used for both suspended sludge in the down-chambers and attached biofilm in the upper-chambers, to identify the presence of denitrifying and nitrifying microorganisms. The highest removal efficiencies in terms of chemical oxygen demand and total nitrogen were obtained in FII, being 91 and ~50%, respectively; effluent concentrations were ~40 mg O2.L-1 and ~15 mg N-TN.L-1. The presence of three groups of bacteria, the denitrifiers, the ammonia oxidants and the nitrite oxidants, was confirmed in the attached biofilm of the RHAE, indicating a mixotrophic biomass and suggesting the possibility of simultaneous nitrification and denitrification process.

Influence of Hip Joint Flexion Angle on the Submerged Dolphin Kick Stroke Based on Numerical Simulation of Multi-Body Motion / 医用生物力学

Objective To explore characteristics of flow field around the athletes, change of net flow force, and influences of hip flexion angles at the end of extension kick on the submerged dolphin kick stroke. Methods The body shape data of a swimmer were obtained by three-dimensional (3D) scanning, and the data were reversely reconstructed to obtain the swimmer model. The joints of the swimmer model were separated, and each segment of the athlete was divided into independent rigid body, and simulation of the submerged dolphin kick stroke was realized by controlling movement of each independent rigid body. The computational fluid dynamics (CFD) software package ANSYS Fluent was used as the solver for calculation and solution. Results The vortex structures were shed off from the surface of the swimmer’s body in the area with a large velocity gradient in flow field, and the shedding of vortex structures was different at the stage of extension kick and flexion kick. Propulsion was mainly generated during extension kick phase. At the end of extension kick, the drag decreased as the hip flexion angle increased from 20° to 30°. Conclusions To some extent, increasing flexion angle of the hip joint at the end of extension kick will reduce the drag force and increase the swimming speed in process of the submerged dolphin kick stroke.

Characteristics of the rhizosphere and phyllosphere microbial community of three submerged plants in the dragon-shaped water system of Beijing / 生物工程学报

Aquatic plants and the epiphytic microorganisms are important contributors to the purification of constructed wetlands. Taking the dragon-shaped water system of Beijing Olympic Park as a model, this study analyzed the structure and function of the microbial communities reside the sediment, the water body and the rhizosphere and phyllosphere of three submerged plants-Vallisneria natans, Myriophyllum verticillatum, and Potamogeton pectinatus using high-throughput sequencing technology. The results showed that the microbial diversity from the highest to the lowest were samples from sediment, plant rhizosphere, plant phyllosphere and water. The microbial diversity of plant phyllosphere samples were significantly higher than those of the water body. LEfSe analysis showed that different habitats enriched different microbial groups. The sediments mainly enriched anaerobic microbes, while the water body and the phyllosphere of plants mainly enriched aerobic microbes, and the rhizosphere of plants had the both. Functional prediction analysis showed that the abundance of denitrification marker genes in phyllosphere samples was higher than that in samples from rhizosphere, sediment and water body, and the abundance of denitrification marker genes in phyllosphere samples of M. verticillatum and P. pectinatus was higher than that of V. natans. This study could serve as a guidance for the selection of submerged plants and functional microorganisms for constructed wetlands.

Isolation and Characterization of Alkaline Pectinase Productive Bacillus tropicus from Fruit and Vegetable Waste Dump Soil

Abstract Alkaline pectinase is the utmost significant industrial enzyme of the bioscouring process. By considering bio scouring of cotton, 30 microbial isolates from fruit and vegetable waste rich dump soil of Solang Valley and Vasishta (Manali, Himachal Pradesh, India) were isolated and screened for the alkaline pectinase production in the current research work. Only four isolates P3, P16, P21, and P27 were capable to produce extracellular alkaline pectinase at pH 9. Further by applying submerged fermentation, the alkaline pectinase production was quantitatively screened. The most efficient isolate was P3 identified as Bacillus tropicus, based on morphological, biochemical, and molecular characterization. Molecular characteristics confirmed by 16S rDNA sequence analysis. The nucleotide sequence of the isolate was novel with a 97% similarity index and submitted to the GenBank with accession number MK332379. The Bacillus strain selected was active at broad pH range from 8-10.5 and a temperature range from 25-50 oC. Optimum pH and temperature observed were 9 and 37 oC respectively and can be suitably used for the bio scouring process for the pretreatment of the fabrics.

La comunidad de peces del arrecife Palo Seco, Veracruz, golfo de México y su relación con los grupos morfofuncionales / The fish community of Palo Seco Reef, Veracruz, gulf of Mexico and its relationship with the morpho functional groups

Resumen Los bancos arrecifales sumergidos funcionan como áreas de reserva de germoplasma, debido a su riqueza y abundancia de especies, lo que favorece el desarrollo de biomasa en arrecifes emergentes vecinos. El objetivo de la presente investigación fue establecer la comunidad de peces del arrecife Palo Seco, Veracruz, México, y su relación con los grupos morfofuncionales que caracterizan al sustrato. Se efectuaron 117 censos visuales con equipo de buceo SCUBA (63 censos aleatorios y 54 transectos en banda) durante los veranos de 2013 y 2016, para determinar la estructura de la comunidad de peces (composición, riqueza, abundancia, biomasa y gremios tróficos) y caracterizar el sustrato, usando los grupos morfofuncionales (GMF) a partir de fototransectos. Las relaciones entre los peces y el sustrato se determinaron mediante un análisis de correspondencia canónica (ACC). La ictiofauna de Palo Seco estuvo compuesta por 109 especies, incluyendo 2 invasoras (Pterois volitans y Neopomacentrus cyanomos), y 3 endémicas de Veracruz (Elacatinus jarocho, Hypoplectrus atlahua e Hypoplectrus castroaguirrei). Halichoeres burekae, Coryphopterus hyalinus y los juveniles de Haemulon aurolineatum fueron las especies más abundantes, mientras que, Sphyraena barracuda, Anisotremus virginicus y Megalops atlanticus dominaron en biomasa. El gremio de los zooplanctívoros fue el más abundante (83.35 %) contrastando con la proporción de herbívoros (1.24 %). Los piscívoros presentaron la mayor biomasa (28.89 %), seguidos de los carnívoros generalistas (28.22 %). El sustrato del arrecife se caracterizó por nueve grupos morfofuncionales. En el ACC se observó un gradiente de los GMF y de la profundidad que se relacionaron con algunas especies de peces y con algunos gremios tróficos. La comunidad ictiológica del arrecife Palo Seco en general, se parece a las comunidades de peces de otros arrecifes veracruzanos, pero su riqueza y abundancia responde a las condiciones locales. El parecido sugiere una posible conectividad regional y resalta su importancia para la conservación.

Abstract The submerged reef banks may play the part of germoplasm reserve, due to their richness and species abundance that contribute to the biomass development in adjacent emergent reefs. The goal of this research was to establish the fish community of Palo Seco Reef, Veracruz, Mexico, and its relationship with morpho functional groups of the substrate. One hundred and seventeen visual censuses (63 random and 54 belt-transects) using SCUBA dive equipment were carried out during the Summers of 2013 and 2016 in order to determine the fish community structure (components, richness, abundance, biomass and trophic guilds) and characterize the substrate based on the morpho functional groups (MFG). The relationships between the fish and the substrate were determined by a canonical correspondence analysis (CCA). The ichthyofaune was represented by 109 species, including 2 invasive species (Pterois volitans and Neopomacentrus cyanomos), and 3 endemic species of Veracruz (Elacatinus jarocho, Hypoplectrus atlahua and Hypoplectrus castroaguirrei). Halichoeres burekae, Coryphopterus hyalinus and juvenile of Haemulon aurolineatum were the most abundant species, whereas Sphyraena barracuda, Anisotremus virginicus and Megalops atlanticus dominated in biomass. The zooplanctivore guild was the most abundant (83.35 %), in contrast with the herbivorous (1.24 %). The piscivorous fish were the most abundant in biomass (28.89 %), followed by the generalized carnivorous fish (28.22 %). Nine MFG characterized the substrate of Palo Seco Reef. The CCA showed a gradient of MFG and depth which were related to some fish species and to some trophic guilds. The ichthyological community of Palo Seco Reef is similar to the fish communities of other reefs in Veracruz, but its richness and abundance respond to the local environment. The similarity suggests a possible regional connectivity and underlines its importance for conservation.

Effect of carbon/nitrogen ratio on polyhydroxyalkanoates production by Bacillus species under submerged fermentation

Aim: To analyze the effect of carbon/nitrogen (C/N) ratio on polyhydroxyalkanoates (PHAs) production by Bacillus species under submerged fermentation process.Methodology: Preserved polyhydroxyalkanoates producing Bacillus sp. C1 (2013) (KF626477) was revived and growth parameters were optimized by one factor at a time approach. The effect of C/N ratio and the influence of time period on polyhydroxyalkanoates production through submerged fermentation process was evaluated under optimized condition. Primary structural and morphological characterization of extracted polyhydroxyalkanoates was carried out by Fourier Transform Infra-Red Spectroscopy and Field Emission-Scanning Electron Microscopy. Results: Bacillus sp. C1 (2013) produced higher cell biomass in mineral salt medium at pH 9.0, temperature 37oC, dextrose (2%) and ammonium sulphate (1%) as carbon and nitrogen source with 15% inoculum size. Under optimized condition, higher polyhydroxyalkanoates production of 1.09 g l-1 (49.2%) was obtained at 48 hrs with 2: 0.4 C/N ratio. However, in our previous study 0.909 gl-1 of PHAs was produced by the bacteria at 6:1 carbon to nitrogen ratio. Fourier Transform Infra-Red Spectroscopic analysis showed high intense absorption bands at 1720.18 cm−1 resembled to ester carbonyl functional group of PHB, which is the most common homopolymer of PHAs. Surface morphology of poly-beta-hydroxybutyrate film was rough and fairly regular as revealed from Field Emission-Scanning Electron Microscopic imaging. Interpretation: Poly-beta-hydroxybutyrate production by the bacteria increased under higher degrees of nitrogen deficient condition. Thus, optimized C/N ratio can improve the cost affordability of poly-beta-hydroxybutyrate production, however, further research in contrast to different bacteria is highly essential in this regard.

Ellagic acid production using polyphenols from orange peel waste by submerged fermentation

Background: Biotechnological processes are part of modern industry as well as stricter environmental requirements. The need to reduce production costs and pollution demands for alternatives that involve the integral use of agro-industrial waste to produce bioactive compounds. The citrus industry generates large amounts of wastes due to the destruction of the fruits by microorganisms and insects together with the large amounts of orange waste generated during the production of juice and for sale fresh. The aim of this study was used orange wastes rich in polyphenolic compounds can be used as source carbon of Aspergillus fumigatus MUM 1603 to generate high added value compounds, for example, ellagic acid and other molecules of polyphenolic origin through submerged fermentation system. Results: The orange peel waste had a high concentration of polyphenols, 28% being condensed, 27% ellagitannins, 25% flavonoids and 20% gallotannins. The major polyphenolic compounds were catechin, EA and quercetin. The conditions, using an experimental design of central compounds, that allow the production of the maximum concentration of EA (18.68 mg/g) were found to be: temperature 30°C, inoculum 2 × 107 (spores/g) and orange peel polyphenols 6.2 (g/L). Conclusion: The submerged fermentation process is an effective methodology for the biotransformation of molecules present in orange waste to obtain high value-added as ellagic acid that can be used as powerful antioxidants, antibacterial and other applications.

Amino Acid Supplementation Improves the Production of Extracellular Peptidases by Aspergillus Section Flavi and their Ionic Immobilization

Abstract Bioprocess studies have been highlighted due to the importance of physiological processes and industrial applications of enzymes. The potential of peptidase production from Aspergillus section Flavi using different amino acids as a supplemental nitrogen source was investigated. A production profile revealed that amino acids had positive effects on peptidase production when compared to the control without amino acids. Optimal production (100 U/mL) was obtained with Arginine amino acid in 96 h of fermentation. Extracellular peptidase from Aspergillus section Flavi was identified in submerged bioprocesses by in situ activity. Biochemical studies revealed that the maximum activities of the enzyme extract were obtained at pH 6.5 and a temperature of 55°C. The inhibition by EDTA and PMSF suggests the presence of more than one peptidase while the Ni2+ and Cu2+ had a negative influence on the enzyme activity. When the crude extract was reversibly immobilized on ionic supports, DEAE-Agarose and MANAE-Agarose the derivative showed different profiles of thermal and pH stabilities. Hence, this study revealed the basic properties and biochemical characteristics that allowed the production improvement of this class of enzyme. Moreover, with known properties stabilization and immobilization process is required to further explore its biotechnological capacities.

Spray Drying of Coloring Extracts Produced by Fungi Isolated from Brazilian Caves

Abstract Pigments produced by submerged fermentation of three filamentous fungi isolated from Brazilian caves, namely Aspergillus keveii, Penicillium flavigenum, and Epicoccum nigrum, were submitted to spray drying in presence of the adjuvants maltodextrin, modified starch or gum arabic. Yellow fine powders with low moisture content and water activity, and high color retention (> 70%) were successfully generated with a high product recovery ratio (> 50%), independently of the adjuvant used. The dried products have enhanced stability and potential to might be used as a natural colorant in food and pharmaceutical applications.

Influence of Oxygen Supply on Growth and Laccases Production by Pleurotus sajor-caju PS-2001 in Submerged Process

Abstract (1) Background: Oxygen supply is an important parameter to be considered in submerged cultures. This study evaluated the influence of different conditions for dissolved oxygen (DO) concentration on laccases activities and growth of Pleurotus sajor-caju PS-2001 in submerged process in stirred-tank bioreactor. (2) Methods: Initially, three different conditions were tested: uncontrolled DO and minimum levels of 30% and 80% of saturation, with the pH controlled between 4.5 and 7.0. (3) Results: Best results were observed at 30% DO (26 U mL-1 of laccases at 96 h), whereas higher mycelial biomass was observed at 30% and 80% DO (above 4.5 g L-1). Four different conditions of DO (uncontrolled, 10%, 30% and 50% of saturation) were tested at pH 6.5, with higher laccases activity (80 U mL-1 at 66 h) and lower mycelial growth (1.36 g L-1 at 90 h) being achieved with DO of 30%. In this test, the highest values for volumetric productivity and specific yield factor were determined. Under the different pH conditions tested, the production of laccases is favoured at DO concentration of 30% of saturation, while superior DO levels favours fungal growth. (4) Conclusion: The results indicate that dissolved oxygen concentration is a critical factor for the culture of P. sajor-caju PS-2001 and has important effects not only on laccases production but also on fungal growth.

Influencing factors on single-cell protein production by submerged fermentation: a review

Since more than twenty years ago, some species of bacteria and fungi have been used to produce protein biomass or single-cell protein (SCP), with inexpensive feedstock and wastes being used as their sources of carbon and energy. The role of SCP as a safe food and feed is being highlighted more because of the worldwide protein scarcity. Even though SCP has been successfully commercialized in the UK for decades, study of optimal fermentation conditions, various potential substrates, and a broad range of microorganisms is still being pursued by many researchers. In this article, commonly used methods for the production of SCP and different fermentation systems are briefly reviewed, with submerged fermentation being highlighted as a more commonly used method. Emphasis is given to the effect of influencing factors on the biomass yield and productivity in an effort to provide a comprehensive review for researchers in related fields of interest.

Review of Lactobacillus in the food industry and their culture media / Revisión de Lactobacilos en la industria alimentaria y sus medios de cultivo

ABSTRACT Lactic acid bacteria (LAB) are currently of great importance given their increasing use in the improvement of human and anima health and nutrition. They exhibit complex nutritional requirements, which is the reason why their production costs are high. Research efforts are being made aimed at evaluating different substrates for their production as well as the production of valuable metabolites from them. The purpose of this paper is to expose the main research and development trends for LAB production for industrial purposes with emphasis on the culture media required for their growth. The web of Science databases as well as the Google Patent Search tool were used in order to gather and analyze the scientific and technical information published in the last twelve years relating to LAB and their culture media. The use of milk, industrial cheese whey, cane molasses, hydrolyzed starches, lignocellulosic materials, organic food waste and bovine blood plasma, among others, have been proposed for Lactobacillus cultivation with the purpose of reducing costs and increasing performance in their production. Research groups and centers have the responsibility of intensifying their efforts to offer highly efficient technological alternatives to the industry that allow the production and application of LAB as a growth factor for the food sector. Also, research in prebiotic ingredients or additives derived from LAB that allow the enhancement of the benefits to the consumer must be continued. In this regard, it is necessary to increase the international visibility of Colombian scientific production in this area.

RESUMEN Las bacterias del ácido láctico (LAB) son actualmente de gran importancia dado su uso creciente en la mejora de la salud y nutrición humana y animal. Presentan requerimientos nutricionales complejos, por lo que sus costos de producción son altos. Se están realizando esfuerzos de investigación para evaluar diferentes sustratos para su producción, así como la producción de metabolitos valiosos a partir de ellos. El propósito de este documento es exponer las principales tendencias de investigación y desarrollo para la producción de LAB con fines industriales, con énfasis en los medios de cultivo necesarios para su crecimiento. Las bases de datos de Web of Science y la herramienta de búsqueda de patentes de Google se utilizaron para recopilar y analizar la información científica y técnica publicada en los últimos doce años relacionada con LAB y sus medios de cultivo. Se ha propuesto el uso de leche, suero de queso industrial, melaza de caña, almidones hidrolizados, materiales lignocelulósicos, desechos de alimentos orgánicos y plasma sanguíneo bovino, entre otros, para el cultivo de Lactobacillus con el fin de reducir costos y aumentar el rendimiento de su producción. Los grupos y centros de investigación tienen la responsabilidad de intensificar sus esfuerzos para ofrecer alternativas tecnológicas altamente eficientes a la industria que permitan la producción y aplicación de LAB como factor de crecimiento para el sector alimentario. Además, la investigación en ingredientes prebióticos o aditivos derivados de LAB que permite la mejora de los beneficios para el consumidor debe continuar. En este sentido, es necesario aumentar la visibilidad internacional de la producción científica colombiana en esta área.