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1.
Microb Cell Fact ; 12: 92, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24112554

RESUMO

BACKGROUND: Given its availability and low price, glycerol derived from biodiesel industry has become an ideal feedstock for the production of fuels and chemicals. A solution to reduce the negative environmental problems and the cost of biodiesel is to use crude glycerol as carbon source for microbial growth media in order to produce valuable organic chemicals. In the present paper, crude glycerol was used as carbon substrate for production of L (+)-lactic acid using pelletized fungus R. oryzae NRRL 395 on batch fermentation. More, the experiments were conducted on media supplemented with inorganic nutrients and lucerne green juice. RESULTS: Crude and pure glycerols were first used to produce the highest biomass yield of R. oryzae NRRL 395. An enhanced lactic acid production then followed up using fed-batch fermentation with crude glycerol, inorganic nutrients and lucerne green juice. The optimal crude glycerol concentration for cultivating R. oryzae NRRL 395 was 75 g l(-1), which resulted in a fungal biomass yield of 0.72 g g(-1) in trial without lucerne green juice addition and 0.83 g g(-1) in trial with lucerne green juice. The glycerol consumption rate was 1.04 g l(-1) h(-1) after 48 h in trial with crude glycerol 75 g l(-1) while in trial with crude glycerol 10 g l(-1) the lowest rate of 0.12 g l(-1) h(-1) was registered. The highest L (+)-lactic acid yield (3.72 g g(-1)) was obtained at the crude glycerol concentration of 75 g l(-1) and LGJ 25 g l(-1), and the concentration of lactic acid was approximately 48 g l(-1). CONCLUSIONS: This work introduced sustainable opportunities for L (+)-lactic acid production via R. oryzae NRRL 395 fermentation on biodiesel crude glycerol media. The results showed good fungal growth on crude glycerol at 75 g l(-1) concentration with lucerne green juice supplementation of 25 g l(-1). Lucerne green juice provided a good source of nutrients for crude glycerol fermentation, without needs for supplementation with inorganic nutrients. Crude glycerol and lucerne green juice ratio influence the L (+)-lactic acid production, increasing the lactate productivity with the concentration of crude glycerol.


Assuntos
Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Ácido Láctico/metabolismo , Rhizopus/citologia , Agregação Celular , Técnicas de Cultura de Células/métodos , Glicerol , Ácido Láctico/biossíntese , Ácido Láctico/isolamento & purificação , Proteínas/metabolismo , Rhizopus/metabolismo , Rhizopus/fisiologia
2.
Front Bioeng Biotechnol ; 10: 888827, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814014

RESUMO

To improve food production via fermentation with co-cultures of microorganisms (e.g., multiple lactic acid bacteria-LAB strains), one must fully understand their metabolism and interaction patterns in various conditions. For example, LAB can bring added quality to bread by releasing several bioactive compounds when adding soy flour to wheat flour, thus revealing the great potential for functional food development. In the present work, the fermentation of three soy and wheat flour mixtures is studied using single cultures and co-cultures of Lactobacillus plantarum and Lactobacillus casei. Bio-chemical processes often require a significant amount of time to obtain the optimal amount of final product; creating a mathematical model can gain important information and aids in the optimization of the process. Consequently, mathematical modeling is used to optimize the fermentation process by following these LAB's growth kinetics and viability. The present work uses both multiple regression and artificial neural networks (ANN) to obtain the necessary mathematical model, useful in both prediction and process optimization. The main objective is to find a model with optimal performances, evaluated using an ANOVA test. To validate each obtained model, the simulation results are compared with the experimental data.

3.
Sci Rep ; 11(1): 18633, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34545115

RESUMO

In this study we aimed to compare the mineralogical, thermal, physicochemical, and biological characteristics of recent organic carbon-rich sediments ('sapropels') from three geographically distant Romanian lakes (Tekirghiol and Amara, SE Romania, and Ursu, Central Romania) with distinct hydrogeochemical origins, presently used for pelotherapy. The investigated lakes were classified as inland brackish Na-Cl-sulfated type (Amara), coastal moderately saline and inland hypersaline Na-Cl types (Tekirghiol and Ursu, respectively). The settled organic matter is largely composed of photosynthetic pigments derived from autochthonous phytoplankton. Kerogen was identified in the sapropel of coastal Tekirghiol Lake suggesting its incipient maturation stage. The mineral composition was fairly similar in all sapropels and mainly consisted of quartz, calcite, and aragonite. Smectite, illite, mixed layer smectite/illite appeared as major clay components. Potentially toxic elements were found in low concentrations. The physical properties (i.e., specific heat, thermal conductivity and retentivity) and cation exchange capacity are comparable to other peloids used for therapy. This study is the first comprehensive multi-approached investigation of the geochemical nature of recent sapropels in Romanian saline lakes and thus contributes to expanding our knowledge on the origin and physicochemical qualities of organic matter-rich peloids with therapeutic uses.

4.
Polymers (Basel) ; 12(1)2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861657

RESUMO

Edible coatings and films represent an alternative packaging system characterized by being more environment- and customer-friendly than conventional systems of food protection. Research on edible coatings requires multidisciplinary efforts by food engineers, biopolymer specialists and biotechnologists. Entrapment of probiotic cells in edible films or coatings is a favorable approach that may overcome the limitations linked with the use of bioactive compounds in or on food products. The recognition of several health advantages associated with probiotics ingestion is worldwide accepted and well documented. Nevertheless, due to the low stability of probiotics in the food processing steps, in the food matrices and in the gastrointestinal tract, this kind of encapsulation is of high relevance. The development of new and functional edible packaging may lead to new functional foods. This review will focus on edible coatings and films containing probiotic cells (obtaining techniques, materials, characteristics, and applications) and the innovative entrapment techniques use to obtained such packaging.

5.
Chem Cent J ; 12(1): 124, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30499033

RESUMO

Most chemical reactions produce unwanted by-products. In an effort to reduce environmental problems these by-products could be used to produce valuable organic chemicals. In biodiesel industry a huge amount of glycerol is generated, approximately 10% of the final product. The research group from University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca developed opportunities to produce L(+) lactic acid from the glycerol. The team is using the Rhizopus oryzae NRRL 395 bacteria for the fermentation of the glycerol. The purpose of the research is to improve the production of L(+) lactic acid in order to optimize the process. A predictive model obtained by neural networks is useful in this case. The main objective of the present work is to present the developed user-friendly application useful in modeling this fermentation process, in order to be used by people who are inexperienced with neural networks or specific software. Besides the interface for training of a new neural network in order to develop the model in some characteristic condition, the software also provides an interface for visualization of the results, useful in interpretation and as a tool for prediction.

6.
Chem Cent J ; 12(1): 88, 2018 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-30078060

RESUMO

The advanced biochemical characterisation of green, red lentil and wheat flours was performed by assessing their folic acid content as well as individual minerals, amino acids, fatty acids and volatile compounds. Moreover, a nutritionally improved wheat-lentil composite flour, with a content of 133.33 µg of folic acid/100 g, was proposed in order to assure the folic acid daily intake (200 µg) for an adult person. The wheat and lentil flours percentages used for the composite were calculated by using the equations for total material balance and folic acid content material balance. Bread was selected as model food for the composite flour due to its high daily intake (~ 250 g day-1) and to its great potential in biofortification. By this algorithm, two composite flours were developed, wheat-green lentil flour (22.21-77.79%) and wheat-red lentil flour (42.62-57.38%), their advanced biochemical characteristics being predicted based on the determined compositions of their constituents. The baking behaviour of the new developed wheat-lentils composite flours with optimised folic acid content was tested. In order to objectively compare the bread samples, texture profile analysis was considered the most relevant test. A good baking behaviour was observed for the wheat-red lentil bread, while for the wheat-green lentil composite flour, encouraging results were obtained.

7.
J Agric Food Chem ; 62(27): 6306-16, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-24938997

RESUMO

Total and individual carotenoids, fatty acid composition of total lipids, and main lipid classes of 16 fresh bee-collected pollen samples from Romania were determined by high-performance liquid chromatography with photodiode array detection and capillary gas chromatography with mass detection. Analyzed samples were found rich in lutein, whereas ß-criptoxanthin and ß-carotene were present in a wide range of amounts correlated with predominant botanical origin of the samples. High amounts of lutein were correlated with the presence of Callendula officinalis, Taraxacum officinale and Anthylis sp. The highest amount of total lipids was found in samples where pollen from Brassica sp. was predominant. Lipid classes were dominated by polyunsaturated fatty acids. Saturated fatty acids were determined in variable amounts. Lipid and carotenoid contents present great variability, explained by the various botanical species present in the samples.


Assuntos
Asteraceae/química , Carotenoides/análise , Ácidos Graxos/análise , Pólen/química , Taraxacum/química , Animais , Abelhas/fisiologia , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Polinização
8.
Chem Cent J ; 7(1): 8, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23327299

RESUMO

BACKGROUND: Calendula officinalis L. (pot marigold) is an annual aromatic herb with yellow or golden-orange flowers, native to the Mediterranean climate areas. Their seeds contain significant amounts of oil (around 20%), of which about 60% is calendic acid. For these reasons, in Europe concentrated research efforts have been directed towards the development of pot marigold as an oilseed crop for industrial purposes. RESULTS: The oil content and fatty acid composition of major lipid fractions in seeds from eleven genotypes of pot marigold (Calendula officinalis L.) were determined. The lipid content of seeds varied between 13.6 and 21.7 g oil/100 g seeds. The calendic and linoleic acids were the two dominant fatty acids in total lipid (51.4 to 57.6% and 28.5 to 31.9%) and triacylglycerol (45.7 to 54.7% and 22.6 to 29.2%) fractions. Polar lipids were also characterised by higher unsaturation ratios (with the PUFAs content between 60.4 and 66.4%), while saturates (consisted mainly of palmitic and very long-chain saturated fatty acids) were found in higher amounts in sterol esters (ranging between 49.3 and 55.7% of total fatty acids). CONCLUSIONS: All the pot marigold seed oils investigated contain high levels of calendic acid (more than 50% of total fatty acids), making them favorable for industrial use. The compositional differences between the genotypes should be considered when breeding and exploiting the pot marigold seeds for nutraceutical and pharmacological purposes.

9.
Chem Cent J ; 6(1): 106, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22995716

RESUMO

BACKGROUND: A systematic mapping of the phytochemical composition of different sea buckthorn (Hippophae rhamnoides L.) fruit subspecies is still lacking. No data relating to the fatty acid composition of main lipid fractions from the berries of ssp. carpatica (Romania) have been previously reported. RESULTS: The fatty acid composition of the total lipids (oils) and the major lipid fractions (PL, polar lipids; FFA, free fatty acids; TAG, triacylglycerols and SE, sterol esters) of the oils extracted from different parts of six sea buckthorn berry subspecies (ssp. carpatica) cultivated in Romania were investigated using the gas chromatography-mass spectrometry (GC-MS). The dominating fatty acids in pulp/peel and whole berry oils were palmitic (23-40%), oleic (20-53%) and palmitoleic (11-27%). In contrast to the pulp oils, seed oils had higher amount of polyunsaturated fatty acids (PUFAs) (65-72%). The fatty acid compositions of TAGs were very close to the compositions of corresponding seed and pulp oils. The major fatty acids in PLs of berry pulp/peel oils were oleic (20-40%), palmitic (17-27%), palmitoleic (10-22%) and linoleic (10%-20%) acids, whereas in seeds PLs, PUFAs prevailed. Comparing with the other lipid fractions the SEs had the highest contents of saturated fatty acids (SFAs). The fatty acid profiles of the FFA fractions were relatively similar to those of TAGs. CONCLUSIONS: All parts of the analyzed sea buckthorn berry cultivars (ssp. carpatica) exhibited higher oil content then the other European or Asiatic sea buckthorn subspecies. Moreover, the pulp/peel oils of ssp. carpatica were found to contain high levels of oleic acid and slightly lower amounts of linoleic and α-linolenic acids. The studied cultivars of sea buckthorn from Romania have proven to be potential sources of valuable oils.

10.
Chem Cent J ; 6(1): 66, 2012 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-22762349

RESUMO

BACKGROUND: Organic agriculture involve plants which are cultivated without using synthetic pesticides, herbicides or fertilizers and promotes biodiversity, biological cycles and improve the product quality. The carotenoids, total polyphenols and the antioxidant activity from skins of some wine and table grapes cultivated in organic and conventional agriculture were studied. RESULTS: The main carotenoids identified using high performance liquid chromatography were lutein and ß-carotene. Muscat Ottonel variety has the highest ß-carotene concentration 504.9 µg/kg for organic and 593.2 µg/kg for conventional grapes. For the organic farming, the total polyphenols content were in the range of 163.23 - 1341.37 mg GAE/kg fresh weight (FW) and 148.47 - 1231.38 mg GAE/kg FW for the conventional grapes. The highest ORAC values were obtained for blue-black variety Napoca in both farming system (43.5 ± 0.95 µmol TE/g organic; 40.4 ± 0.5 µmol TE/g conventional) and lowest for Aromat de Iasi (16.8 ± 0.6 µmol TE/g organic; 14.7 ± 1.6 µmol TE/g conventional). Napoca variety showed also the highest antioxidant activity measured by DPPH method in both cultivated system. CONCLUSION: Nine grape varieties cultivated in organic and conventional systems were compared regarding the carotenoids, total polyphenols and antioxidant activity. The white grape varieties have a higher carotenoids content compared with the blue-black cultivars while the blue-black varieties contain higher TPC and exhibit higher antioxidant activity (except for Muscat Hamburg-ORAC). Vitis vinifera grape skins originating from wine or table grape varieties can be used as a potential source of natural antioxidants.

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