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Brazilian Archives of Biology and Technology, Volume: 57, Número: 1, Publicado: 2014
  • Characterization of Rhizobacteria from field grown Genetically Modified (GM) and non-GM maizes Agriculture, Agribusiness And Biotechnology

    Bumunang, Emmanuel Wihkochombom; Babalola, Olubukola Oluranti

    Resumo em Inglês:

    This study was done to examine the rhizobacteria from field grown Genetically Modified (GM) maize and its non-GM counterpart. Rhizospheric soil samples were collected at 30 days after sowing (DAS) and at post-harvest from two experimental fields in Gauteng, South Africa. Total rhizobacteria (cfu/g) in GM and non-GM soil samples was not significantly different across the different media 30 DAS and at post-harvest. Rhizobacterial isolates obtained were biochemically characterized using the analytical profile index. Species of Pseudomonas, Aeromonas, Sphingomonas, Burkholderia, Stenotrophomonas, Achromobacter, Ewingella and Bacillus were screened in vitro for plant growth promoting traits such as, ammonia production, catalase activity, indole acetic acid production, phosphate solubilisation, hydrogen cyanide production and antifungal activity. All the 32 rhizobacterial strains tested in this study were positive for catalase activity, ammonia production and IAA production; 90.6% were positive for phosphate solubilisation, 34.3% for indicate antifungal activity but none for hydrogen cyanide production. These findings contributed to the quest for potential biofertilizers and biocontrol agents for sustainable agriculture.
  • Effect of buctril super (Bromoxynil) herbicide on soil microbial biomass and bacterial population Agriculture, Agribusiness And Biotechnology

    Abbas, Zafar; Akmal, Muhammad; Khan, Khalid Saifullah; Fayyaz-ul-Hassan,

    Resumo em Inglês:

    The present study aimed to evaluate the effect of bromoxynil herbicide on soil microorganisms, with the hypothesis that this herbicide caused suppression in microbial activity and biomass by exerting toxic effect on them. Nine sites of Punjab province (Pakistan) those had been exposed to bromoxynil herbicide for about last ten years designated as soil 'A' were surveyed in 2011 and samples were collected and analyzed for Microbial Biomass Carbon (MBC), Biomass Nitrogen (MBN), Biomass Phosphorus (MBP) and bacterial population. Simultaneously, soil samples from the same areas those were not exposed to herbicide designated as soil 'B' were taken. At all the sites MBC, MBN and MBP ranged from 131 to 457, 1.22 to 13.1 and 0.59 to 3.70 µg g-1 in the contaminated soils (Soil A), which was 187 to 573, 1.70 to 14.4 and 0.72 to 4.12 µg g-1 in the soils without contamination (soil B). Bacterial population ranged from 0.67 to 1.84x10(8) and 0.87 to 2.37x10(8) cfu g-1 soil in the soils A and B, respectively. Bromoxynil residues ranged from 0.09 to 0.24 mg kg-1 at all the sites in soil A. But no residues were detected in the soil B. Due to lethal effect of bromoxynil residues on the above parameters, considerable decline in these parameters was observed in the contaminated soils. Results depicted that the herbicide had left toxic effects on soil microbial parameters, thus confirmed that continuous use of this herbicide affected the quality of soil and sustainable crop production.
  • Growth characteristics modeling of Lactobacillus acidophilus using RSM and ANN Agriculture, Agribusiness And Biotechnology

    Meena, Ganga Sahay; Kumar, Nitin; Majumdar, Gautam Chandra; Banerjee, Rintu; Meena, Pankaj Kumar; Yadav, Vijesh

    Resumo em Inglês:

    The culture conditions viz. additional carbon and nitrogen content, inoculum size, age, temperature and pH of Lactobacillus acidophilus were optimized using response surface methodology (RSM) and artificial neural network (ANN). Kinetic growth models were fitted to cultivations from a Box-Behnken Design (BBD) design experiments for different variables. This concept of combining the optimization and modeling presented different optimal conditions for L. acidophilus growth from their original optimization study. Through these statistical tools, the product yield (cell mass) of L. acidophilus was increased. Regression coefficients (R²) of both the statistical tools predicted that ANN was better than RSM and the regression equation was solved with the help of genetic algorithms (GA). The normalized percentage mean squared error obtained from the ANN and RSM models were 0.06 and 0.2%, respectively. The results demonstrated a higher prediction accuracy of ANN compared to RSM.
  • In vitro micropropagation of Stevia rebaudiana Bertoni in Malaysia Agriculture, Agribusiness And Biotechnology

    Razak, Ummi Nur Ain Abdul; Ong, Chong Boon; Yu, Tiew Sing; Lau, Li Kiaw

    Resumo em Inglês:

    Stevia rebaudiana Bertoni is a medicinal plants and commercially use as non-caloric sweetener for diabetic patient. In the present study, a protocol was developed for in vitro micropropagation using 6-benzylamino purine (BAP) and Kinetin (Kn) for the formation of multiple shoot proliferation and Indole-3-acetic acid (IAA), Indole-3-butyric acid (IBA) and 1-Naphthaleneacetic acid (NAA) for the induction of roots. Maximum shoot formation (7.82 ± 0.7 shoots per explants) was observed on a Murashige and Skoog (MS) medium supplemented with 0.5 mg L-1 BAP and 0.25 mg L-1 Kn. The maximum number of roots (30.12 ± 2.1 roots per explants) was obtained on a MS medium containing 1.0 mg L-1 IBA. The well rooted plantlets were successfully weaned and acclimatized in plant soil with survival rate of 83.3 %.
  • Evaluation of rat plasma proteins after bothropic venom inoculation and treatment with Mesenquimal stem cells Human And Animal Health

    Telles, Thalita Costa; Michel, Ana Flávia Ribeiro Machado; Lúcia, Maria; Melo, Bruno Martins; Bicalho, Adriane Costa-Val Pimenta; Ocarino, Natália Melo; Melo, Marilia Martins

    Resumo em Inglês:

    The aim of this work was to evaluate the mesenchymal stem cells treatment of rats with myonecrosis caused by Rhinocerophis alternatus venom through acute phase proteins (APP) profile. The animals were distributed into three experimental groups (G1, G2 and G3). G1 and G2 were inoculated with 120 μg of R. alternatus venom diluted in 200 µL of ultra-pure water in gastrocnemic muscle, while G3 received 200 µL of ultra-pure water. Three days after, G1 was treated with 5 X 10(6) MSC diluted in PBS and G2 and G3 only with PBS. Each three days after the treatments (3rd, 6th, 9th, 12th 15th days), blood of five animals in each group was collected in order to evaluate the APP. A decrease (P<0.05) in α2-globulin fraction was observed in G1 on the 6th day. In G1 and G2, a raise (P<0.05) was observed in β globulin, a common occurrence in the late phases of inflammatory process, although no significant difference was observed between them. Concerning gamma globulins levels, on the 6th day after the treatments, in G1 and G2 groups, increase in the levels was observed. These data showed that the MSC treatment after bothropic envenomation in the rats caused alteration in APP.
  • Telomerase reverse transcriptase mediated immortalization of human bone marrow stromal cells Human And Animal Health

    Teng, Yong; Hu, YunYu; Li, Xu Sheng; Wang, Zhen; Wang, Rui

    Resumo em Inglês:

    Primary human bone marrow stromal cells (hMSCs) were transfected with human telomerase reverse transcriptase (hTERT) gene with lipofection method. The hTERT transfected hMSCs of passage 100 underwent chondrogenesis induction with dexamethasone, transforming the growth factor β and vitamin C, osteogenesis induction with dexamethasone, β glycerophosphoric acid and vitamin C, and cardiomyocyte induction with 5-azacytidine. After 7, 14, 21 and 28 days of induction, immunocytochemistry was performed to detect the expressions of type I and II collagen and osteocalcin, and alizarin red staining was performed to detect the bone nodule formation in osteogenesis induction. Immunocytochemistry was carried out to detect the striated muscle actin expression in cardiomyocytes. The hMSCs undergoing successful transfection were positive for the hTERT. The hTERT transfected cells were grown in vitro successfully and passaged for 136 generations. Results showed that these cells could be induced to differentiate into chondrocytes, bone and myocardial cells. Introduction of exogenous hTERT into hMSCs could achieve immortalized hMSCs with the potential of multi-directional differentiation. Thus, these cells could be applied as seed cells in tissue engineering.
  • The constitutive expression of the V gene of Parainfluenza virus 5 affects the growth properties of bovine herpesvirus 5 Human And Animal Health

    Lima, Francisco Esmaile de Sales; Batista, Helena Beatriz Ruthner; Campos, Fabrício Souza; Kunert Filho, Hiran Castagnino; Cibulski, Samuel; Finoketti, Fernando; Arantes, Thalita; Spilki, Fernando; Roehe, Paulo Michel; Rijsewijk, Franciscus Antonius Maria; Franco, Ana Cláudia

    Resumo em Inglês:

    This study aimed to analyze the effect of the expression of Parainfluenza virus 5 (PIV5) V protein in bovine cells on the replication of Bovine herpesvirus 5 (BoHV-5). Growth properties of BoHV-5 were evaluated in parental and PIV5 transfected cells. In one-step growth experiments, the BoHV-5 reached higher titers at earlier time points in the transfected cells when compared to the parental cells. The mean plaque size produced by the BoHV-5 in transfected cells was larger than the parental cells. This indicated that the expression of the PIV5 V gene facilitated the release and cell-to-cell spread of BoHV-5 in bovine cells.
  • The effects of low level laser therapy on injured skeletal muscle Human And Animal Health

    Renno, Ana Claudia Muniz; Assis, Lívia; Peres, Beatriz; Rodrigues, Natalia Camargo; Brunelli, Roberta de Matos; Toma, Renata Luri; Medalha, Carla Christina; Ribeiro, Daniel Araki

    Resumo em Inglês:

    The main purpose of the present study was to investigate the effects of low-level laser therapy (LLLT) used in two different fluencies on injured skeletal muscle after cryolesion by means of histopathological analysis and immunohistochemistry for COX-2. A total of sixty male Wistar rats were randomly distributed into three groups: injured animals without any treatment; 808 nm laser treated group, at 10 J/cm² and 808 nm laser treated group, at 50 J/cm². Each group was divided into two different subgroups (n=10) on days 6 and 13 post-injury. The results showed that the animals irradiated with laser at 10 J/cm² or 50 J/cm² presented the areas with cell infiltrate and pointed out to minor and mild areas with destroyed zones compared with the control group. Also, a COX-2 downregulation was noticed in the groups exposed to laser at two fluences evaluated in this study. Significant statistically differences (p<0.05) were noticed to collagen deposition in the laser treated animals, with the fluence of 50 J/cm² when compared to the other groups on day 13 post-surgery. Taken together, these results suggested that laser therapy could have positive effects on muscle repair in the rats after cryolesion.
  • Agrowaste-based Polyhydroxyalkanoate (PHA) production using hydrolytic potential of Bacillus thuringiensis IAM 12077 Biological And Applied Sciences

    Gowda, Vaishnavi; Shivakumar, Srividya

    Resumo em Inglês:

    The study identified the innate enzymatic potential (amylase) of the PHB producing strain B.thuringiensis IAM 12077 and explored the same for cost-effective production of PHB using agrowastes, eliminating the need for pretreatment (acid hydrolysis and/or commercial enzyme). Comparative polyhydroxyalkanoate (PHA) production by B. thuringiensis IAM 12077 in biphasic growth conditions using glucose and starch showed appreciable levels of growth (5.7 and 6.8 g/L) and PHA production (58.5 and 41.5%) with a PHA yield of 3.3 and 2.8 g/L, respectively. Nitrogen deficiency supported maximum PHA yield (2.46 g/L) and accumulation (53.3%). Maximum growth (3.6 g/L), PHB yield (2.6 g/L) and PHA accumulation (72.8%) was obtained with C:N ratio of 8:1 using starch as the carbon source (10 g/L). Nine substrates (agro and food wastes) viz. rice husk, wheat bran, ragi husk, jowar husk, jackfruit seed powder, mango peel, potato peel, bagasse and straw were subjected to two treatments- acid hydrolysis and hydrolysis by innate enzymes, and the reducing sugars released thereby were utilized for polymer production. All the substrates tested supported comparable PHB production with acid hydrolysis (0.96 g/L-8.03 g/L) and enzyme hydrolysis (0.96 g/L -5.16 g/L). Mango peel yielded the highest PHB (4.03 g/L; 51.3%), followed by jackfruit seed powder (3.93 g/L; 29.32%). Varied levels of amylase activity (0.25U-10U) in all the substrates suggested the enzymatic hydrolysis of agrowastes.
  • Isolation of new steroids of Kala Dhaman grass (Cenchrus setigerus) and evaluation of their bioactivity Biological And Applied Sciences

    Singariya, Premlata; Kumar, Padma; Mourya, Krishan Kumar

    Resumo em Inglês:

    The present study was carried out to determine the possible bioactive components (steroids) of Cenchrus setigerus using GC-MS analysis and in vivo estimation of metabolites (total soluble sugar, soluble protein, proline and total phenolics), photosynthetic pigments (chlorophyll-a, chlorophyll-b and carotenoids) of seedlings and antimicrobial activity of extracts in various polar solvents from the leaves of C. setigerus. Antimicrobial activity was evaluated against three Gram-negative bacteria, including Proteusmirabilis, Klebsiella pneumonia and Agrobacterium tumefaciens andone fungus Aspergillus niger using 'disc diffusion' method, followed by the determination of minimum inhibitory concentrations (MIC) by broth dilution method. Results revealed the presence of some steroids in the isopropyl alcohol extract of C. setigerus:which are (22E)-stigmasta-4,22-dien-3-one(4.93%), δ4-sitosterol-3-one (stigmast-4-en-3-one) (4.31%), fagarsterol (lupeol) (1.25%) and ethyl iso-allocholate (0.32%). Total soluble sugars and chlorophyll-a were also recorded to be highest. The highest activity was exhibited by the isopropyl alcohol and ethyl acetate extract against P. mirabilis.
  • Molecular characteristics, recombinant expression and activity detection of OsGSTL1 from rice Biological And Applied Sciences

    Hu, Tingzhang; Yang, Yongwei; Tan, Lili; Yang, Junnian; Wu, Yingmei

    Resumo em Inglês:

    The mRNA of OsGSTL1 was detected in the roots and leaves of rice plants at seedling and tillering stages, and their roots, leaves and panicles at the heading stage. The full-length open reading frame of OsGSTL1 cDNA was 732 bp and encoded a putative polypeptide of 243 amino acids with a calculated molecular mass of 27.30 kDa and a theoretical pI of 5.50. The protein sequences of OsGSTL1 exhibited typical feature of the lambda class GST, which contained the conserved domain "GST_C_Lambda" in C-terminal alpha helical domain and a highly conserved Cys42 in active center. In silico predictions showed that the OsGSTL1 protein was strongly hydrophilic. The phylogenetic analysis revealed OsGSTL1 belonged to monocots subgroup and was closer to IN2-1 of Z. may. The OsGSTL1 gene was cloned into pYTV vector and was introduced into yeast strain PEP4. Western blot analysis showed that the exogenous OsGSTL1 was expressed in the transformed yeast. The GST activity of the crude extracts of yeast showed that the OsGSTL1 transgenic yeast had higher levels of GST activities than the control yeasts. These findings suggested that the OsGSTL1 was a glutathione S-transferase and could play an important role during the growth and development processes in rice.
  • Protective effects of Spirulina on the liver function and hyperlipidemia of rats and human Biological And Applied Sciences

    El-Sheekh, Mostafa Mohamed; Hamad, Saied Mohamed; Gomaa, Mahmoud

    Resumo em Inglês:

    In the present study, the effects of Spirulina on subchronic treatments (two weeks) of hyperlipidemia and liver function of the rats and humans were investigated. The hyperlipidemia was induced in the rats using 25% of soya bean oil and 25% butter. The butter induced more hyperlipidemia than soya bean oil. Spirulina was used at the concentrations of 0, 2.5, 5.0 and 10 % of diet weight of the rats. The decrease in hyperlipidemia by Spirulina was dependent on its concentration in the diet. In case of human studies, about four g/day of Spirulina was taken via oral administration by Egyptian volunteers patients with hyperlipidemia. Spirulina decreased the levels of hyperlipidemia in these patients. The effects were dependent on the amount and number of administered dose of Sprirulina. The results suggested that the Spirulina treatment could induce marked reduction of aminotransferase through correcting lipid profile and increasing high density lipoprotein.
  • SNPs genotyping technologies and their applications in farm animals breeding programs: review Biological And Applied Sciences

    Koopaee, Hamed Kharrati; Koshkoiyeh, Ali Esmailizadeh

    Resumo em Inglês:

    Single nucleotide polymorphisms (SNPs) are DNA sequence variations that occur when a single nucleotide: adenine (A), thymine (T), cytosine (C) or guanine (G) in the genome sequence is altered. Traditional and high throughput methods are two main strategies for SNPs genotyping. The SNPs genotyping technologies provide powerful resources for animal breeding programs.Genomic selection using SNPs is a new tool for choosing the best breeding animals. In addition, the high density maps using SNPs can provide useful genetic tools to study quantitative traits genetic variations. There are many sources of SNPs and exhaustive numbers of methods of SNP detection to be considered. For many traits in farm animals, the rate of genetic improvement can be nearly doubled when SNPs information is used compared to the current methods of genetic evaluation. The goal of this review is to characterize the SNPs genotyping methods and their applications in farm animals breeding.
  • Hydrolysis of insoluble fish protein residue from whitemouth croaker (Micropogonias furnieri) by fungi Food/feed Science And Technology

    Martins, Vilásia Guimarães; Palezi, Simone Canabarro; Costa, Jorge Alberto Vieira; Prentice, Carlos

    Resumo em Inglês:

    A significant amount of insoluble fibrous protein, in the form of feather, hair, scales, skin and others are available as co-products of agro industrial processing. These wastes are rich in keratin and collagen. This study evaluated different fungi for the hydrolysis of insoluble fish protein residues. Proteins resulting from Micropogonias furnieri wastes through pH-shifting process were dried and milled for fermentation for 96 h. This resulted the production of keratinolytic enzymes in the medium. Trichoderma sp. on alkaline substrate (28.99 U mL-1) and Penicillium sp. on acidic substrate (31.20 U mL-1) showed the highest proteolytic activities. Penicillium sp. showed the largest free amino acid solubilization (0.146 mg mL-1) and Fusarium sp. the highest protein solubilization (6.17 mg mL-1).
  • Comparison of fatty acid content of fresh and frozen fillets of rainbow trout (Oncorhynchus mykiss) Walbaum Food/feed Science And Technology

    Chávez-Mendoza, Celia; García-Macías, José Arturo; Alarcón-Rojo, Alma Delia; Ortega-Gutiérrez, Juan Ángel; Holguín-Licón, Celia; Corral-Flores, Gabriela

    Resumo em Inglês:

    The aim of this study was to evaluate and compare the percentage content of fatty acids (FA) of 54 rainbow trout fresh and frozen fillets. Frozen fillets were stored at -15ºC for 45 and 90 days. Saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), omega-6 (n-6) and omega-3 (n-3) fatty acids were determined by gas chromatograph coupled to mass spectrometry. The results indicated that during frozen storage, SFA and MUFA content increased by 32.63 and 9.25%, respectively, while PUFA content decreased by 25.3%, n-6 by 12.4% and n-3 by 32.55%. These changes were more significant (P ≤ 0.05) during the first 45 d of storage. It was concluded that the frozen storage had a negative impact on meat quality of rainbow trout due to the reduction of PUFA, n-3/n-6, polyene index and PUFA/ SFA and the increase of the SFA, and atherogenic and thrombogenic indexes, which meant a substantial loss of nutritional value in the fillets of rainbow trout.
  • Stability of phenolic compounds and antioxidant capacity of regular and decaffeinated coffees Food/feed Science And Technology

    Vicente, Silvio José Valadão; Queiroz, Yara Severino; Gotlieb, Sabina Léa Davidson; Torres, Elizabeth Aparecida Ferraz da Silva

    Resumo em Inglês:

    This study compared the regular and decaffeinated coffees in relation to antioxidant capacity, levels of some antioxidant molecules and stability of these parameters over a six-month period under different storage conditions. The regular coffee samples analyzed right after the industrial production showed higher antioxidant capacity (ORAC and DPPH), the same levels of phenolic compounds and higher levels of phenolic acids than decaffeinated coffee. After six months, the closed packs of both the grades kept under vacuum at 20°C did not show significant changes from the initial results; the open packs stored at 4°C showed small but statistically significant reductions and the open packs stored at 20°C showed higher and statistically significant losses (p < 0.05). Oxygen was the most important factor for these losses but temperature also played an important role. Tests showed that the storage conditions were very important to preserve the quality of coffees regarding the analyzed parameters.
  • Biofiltration of volatile organic compounds of Brazilian gasoline Environmental Sciences

    Rizzolo, Joana Antunez; Santos, Vanessa Cristina de Castro; Soares, Marlene; Woiciechowski, Adenise Lorenci; Soccol, Carlos Ricardo

    Resumo em Inglês:

    Gasoline vapors pollute the atmosphere and can be harmful to human and animal health. Tons of particles of this pollutant are expelled to the atmosphere, generating great economic losses to the industries and serious damage to the environment. Biofiltration is an option of simple technology with low costs that can be used for the gasoline vapor treatment. The present study was carried out in two biofilter systems of laboratorial scale. The biofilter system 1 was operated with a total volume of 2.72 L (four columns) and the biofilter 2 with 2.04 L (three columns) of total volume. Both of them were operated in sequence, with airflow of 450 mL entering each one. Results obtained were as follows for the removal efficiency (RE) of different gasoline vapor concentrations in the air: 1.3 g.m-3 during 35 days, RE of 100%; 3 g.m-3 during 52 days, RE of 90%; 4.5 g.m-3 during 48 days, RE of 70-80% and 8g.m-3 during 28 days, RE of 70%.
  • Plant cells in the context of climate change Environmental Sciences

    Machado, Marcelo Rubens

    Resumo em Inglês:

    Global warming and its origins triggered the beginning to considerable discussion in the last century. Studies of climate models presented in multidisciplinary scientific reports suggest that anthropogenic activities, particularly the emission of gases from the greenhouse effect, are greatly responsible for the current climate changes. The increase of carbon dioxide (CO2) atmospheric concentration has been in discussion in the news, scientific meetings and in public policy debates in several countries. Apart from its impact on global warming, the rising atmospheric CO2 has alerted the scientific community to the need to investigate any morpho-physiological alterations in the plants, given their direct influence on photosynthesis. This article aims to discuss cellular aspects related to plant growth, their behavior of cuticular waxes and the responses of the stomatal development arising from the chemical change to the atmosphere, which are the causes of serious concern and discussion.
  • Production and characterization of surface-active compounds from Gordonia amicalis Environmental Sciences

    Jackisch-Matsuura, Ani Beatriz; Santos, Leonardo Silva; Eberlin, Marcos Nogueira; Faria, Andréia Fonseca de; Matsuura, Takeshi; Grossman, Matthew James; Durrant, Lucia Regina

    Resumo em Inglês:

    Two methods were used to make crude preparations of surface-active compounds (SACs) produced by Gordonia amicalis grown on the medium containing 1% diesel oil. Using a 2:1 (v/v) solution of chloroform:methanol for extraction, Type I SACs were isolated and shown to produce oil in water (O/W) emulsions. Type II SACs were isolated by precipitation with ammonium sulfate and produced predominantly water in oil emulsions (W/O). The crude Type I and II preparations were able to produce a significant reduction in the surface tension of water; however, the crude Type II preparation had 10-25 fold higher emulsification activity than the Type I preparation. Both SAC preparations were analyzed by the TLC and each produced two distinct bands with Rf 0.44 and 0.62 and Rf 0.52 and 0.62, respectively. The partially purified SACs were characterized by the ESI(+)-MS, FT-IR and NMR. In each one of these fractions, a mixture of 10 oligomers was found consisting of a series of compounds, with masses from 502 to 899, differing in molecular mass by a repeating unit of 44 Daltons. The mass spectra of these compounds did not appear to match other known biosurfactants and could represent a novel class of these compounds.
  • Production of polyhydroxyalkanoates (PHAs) by Bacillus subtilis and Escherichia coli grown on cane molasses fortified with ethanol Engineering, Technology And Techniques

    Gomaa, Eman Zakaria

    Resumo em Inglês:

    The aim of this work was to study the production of polyhydroxyalkanoates (PHAs) by Bacillus subtilis and Escherichia coli isolated from the industrial contaminated soil samples using cane molasses as an inexpensive substrate. The amount of PHA accumulated followed a similar pattern to its growth for each of treatment indicating a growth-related production, yielding maximum PHA production of 54.1 and 47.16% for B. subtilis and E. coli, respectively after 96 h cultivation in the medium containing 6 and 8 % molasses, respectively and decreased thereafter. The growth and PHA yields were improved by introducing 1% ethanol into the molasses medium. Ammonium sulphate and ammonium nitrate at a concentration of 1 g/L served as the best nitrogen sources for bacterial growth, allowing B. subtilis and E. coli cells to accumulate PHA up to 62.21 and 58.7%, respectively. The optimum environmental conditions that influenced the PHA production by the two strains were inoculum concentration of 8%, pH 7.0 and a temperature of 35°C. The functional groups of the extracted PHA granules were identified by Fourier transform infrared (FTIR) spectroscopy analysis.
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