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Francisco J Arba - One of the best experts on this subject based on the ideXlab platform.
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innovative technologies for the recovery of phytochemicals from Stevia rebaudiana bertoni leaves a review
Food Chemistry, 2018Co-Authors: Danijela Bursac Kovacevic, Marta Maras, Francisco J Arba, Daniel Granato, Shahi Roohinejad, Kuma Mallikarjuna, Domenico Montesano, Jose M Lorenzo, Predrag PutnikAbstract:Abstract Stevia rebaudiana Bertoni has gained increased industrial and scientific interests in the last 20 years, representing a suitable nutritional alternative to sucrose and artificial sweeteners. Moreover, this plant contains polyphenols, chlorophylls, and carotenoids that may be extracted for production of nutraceuticals and functional foods. Because of nutritional and technological advantages over sucrose, innovative approaches for the extraction of highly valued compounds from Stevia leaves have been developed and optimized. In contrast to conventional alternatives, innovative extraction methods allow higher yields in a shorter time, less usage of organic solvents, and reduced energy consumption. In this paper, the use of innovative extraction techniques: MAE, UAE, HPAE, PLE, SFE, PEF, HVED, cold plasma, and RSLDE for the recovery of non-nutrients with putative health benefits from Stevia leaves is discussed.
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pressurized hot water extraction phwe for the green recovery of bioactive compounds and steviol glycosides from Stevia rebaudiana bertoni leaves
Food Chemistry, 2018Co-Authors: Danijela Bursac Kovacevic, Francisco J Arba, Daniel Granato, Charis M Galanakis, Zora Herceg, Verica Dragovicuzelac, Predrag PutnikAbstract:Abstract Stevia rebaudiana Bertoni leaves are a natural source of diterpenic glycosides, and various bioactive compounds. The objectives were to characterize antioxidants and steviol glycosides in the extracts obtained from Stevia after “green” pressurized hot water extraction (PHWE). PHWE extracts were obtained at different temperatures (100, 130, 160 °C); static extraction times (5 and 10 min), and cycle numbers (1, 2, 3) using a constant pressure of 10.34 MPa. Temperature was the most important parameter for extraction, where the highest recoveries of all bioactive compounds (except for carotenoids) were at 160 °C. Extracts obtained at longer static times had more steviol glycosides, condensed tannins, and chlorophyll A. Higher amounts of total phenols, condensed tannins, and steviol glycosides were obtained under higher cycle numbers. This study indicated that PHWE is useful for recovering polar and nonpolar antioxidants and steviol glycosides. PHWE may be a suitable technique for scale-up to industrial applications.
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evaluating the potential of cell disruption technologies for green selective extraction of antioxidant compounds from Stevia rebaudiana bertoni leaves
Journal of Food Engineering, 2015Co-Authors: Francisco J Arba, Nabil Grimi, Eugene VorobievAbstract:Abstract An increased interest has been shown by both food technologists and food industry regarding Stevia rebaudiana Bertoni leaves ( Stevia ) for their high content of bioactive components (phenolic compounds, vitamin C, carotenoids). The aim of this work was to study the effect of emerging technologies such as high voltage electrical discharges (HVED) and pulsed electric fields (PEF) and ultrasounds (US) on the intensification of the extraction of valuable compounds from Stevia leaves. The proposed processes combined pretreatment (HVED, PEF and US) and extraction of intracellular compounds using water as solvent at ambient temperature. The energy inputs of the treatments varied from 24 to 141 kJ/kg and the results were compared to control diffusion experiments. Chlorophyll a, and b, total carotenoid, total phenolic compounds and antioxidant capacity (DPPH) were determined. A significant increase in soluble matter and antioxidant compounds was found after HVED, PEF and US-assisted extraction as compared to control samples. Results showed that HVED, PEF and US treatments improved both kinetics and extraction yield of soluble matter. These results show the ability of HVED to be used as a potential technology to enhance protein recovery using water and avoiding the use of other solvents and grinding. Chlorophyll content was significantly higher (3-fold increase) after HVED assisted extraction at 141 kJ/kg in comparison to control sample (0.352 and 0.355 mg/L for chlorophyll a and b, respectively). The same energy input for HVED permitted attain highest extraction diffusivities of total soluble matter ( D = 3.06 × 10 −09 m 2 /s), followed by total phenolic compounds ( D = 2.60 × 10 −10 m 2 /s) and then proteins ( D = 6.00 × 10 −11 m 2 /s).
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Stevia rebaudiana bertoni as a natural antioxidant antimicrobial for high pressure processed fruit extract processing parameter optimization
Food Chemistry, 2014Co-Authors: Francisco J Arba, M Criado, Clara Miracle Eldagalbis, Maria J Esteve, D RodrigoAbstract:Abstract Response surface methodology was used to evaluate the optimal high pressure processing treatment (300–500 MPa, 5–15 min) combined with Stevia rebaudiana (Stevia) addition (0–2.5% (w/v)) to guarantee food safety while maintaining maximum retention of nutritional properties. A fruit extract matrix was selected and Listeria monocytogenes inactivation was followed from the food safety point of view while polyphenoloxidase (PPO) and peroxidase (POD) activities, total phenolic content (TPC) and antioxidant capacity (TEAC and ORAC) were studied from the food quality point of view. A combination of treatments achieved higher levels of inactivation of L. monocytogenes and of the oxidative enzymes, succeeding in completely inactivating POD and also increasing the levels of TPC, TEAC and ORAC. A treatment of 453 MPa for 5 min with a 2.5% (w/v) of Stevia succeeded in inactivating over 5 log cycles of L. monocytogenes and maximizing inactivation of PPO and POD, with the greatest retention of bioactive components.
Predrag Putnik - One of the best experts on this subject based on the ideXlab platform.
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innovative technologies for the recovery of phytochemicals from Stevia rebaudiana bertoni leaves a review
Food Chemistry, 2018Co-Authors: Danijela Bursac Kovacevic, Marta Maras, Francisco J Arba, Daniel Granato, Shahi Roohinejad, Kuma Mallikarjuna, Domenico Montesano, Jose M Lorenzo, Predrag PutnikAbstract:Abstract Stevia rebaudiana Bertoni has gained increased industrial and scientific interests in the last 20 years, representing a suitable nutritional alternative to sucrose and artificial sweeteners. Moreover, this plant contains polyphenols, chlorophylls, and carotenoids that may be extracted for production of nutraceuticals and functional foods. Because of nutritional and technological advantages over sucrose, innovative approaches for the extraction of highly valued compounds from Stevia leaves have been developed and optimized. In contrast to conventional alternatives, innovative extraction methods allow higher yields in a shorter time, less usage of organic solvents, and reduced energy consumption. In this paper, the use of innovative extraction techniques: MAE, UAE, HPAE, PLE, SFE, PEF, HVED, cold plasma, and RSLDE for the recovery of non-nutrients with putative health benefits from Stevia leaves is discussed.
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pressurized hot water extraction phwe for the green recovery of bioactive compounds and steviol glycosides from Stevia rebaudiana bertoni leaves
Food Chemistry, 2018Co-Authors: Danijela Bursac Kovacevic, Francisco J Arba, Daniel Granato, Charis M Galanakis, Zora Herceg, Verica Dragovicuzelac, Predrag PutnikAbstract:Abstract Stevia rebaudiana Bertoni leaves are a natural source of diterpenic glycosides, and various bioactive compounds. The objectives were to characterize antioxidants and steviol glycosides in the extracts obtained from Stevia after “green” pressurized hot water extraction (PHWE). PHWE extracts were obtained at different temperatures (100, 130, 160 °C); static extraction times (5 and 10 min), and cycle numbers (1, 2, 3) using a constant pressure of 10.34 MPa. Temperature was the most important parameter for extraction, where the highest recoveries of all bioactive compounds (except for carotenoids) were at 160 °C. Extracts obtained at longer static times had more steviol glycosides, condensed tannins, and chlorophyll A. Higher amounts of total phenols, condensed tannins, and steviol glycosides were obtained under higher cycle numbers. This study indicated that PHWE is useful for recovering polar and nonpolar antioxidants and steviol glycosides. PHWE may be a suitable technique for scale-up to industrial applications.
Nima W Megeji - One of the best experts on this subject based on the ideXlab platform.
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cultivation of Stevia Stevia rebaudiana bert bertoni a comprehensive review
Advances in Agronomy, 2006Co-Authors: K Ramesh, Virendra Singh, Nima W MegejiAbstract:Stevia rebaudiana (Bert.) Bertoni is one of the 154 members of the genus Stevia. It is a sweet herb of Paraguay. The leaves of the shrub contain specific glycosides, which produce a sweet taste but have no caloric value. For centuries, this herbal sweetener has been used by native Guarani Indians to counteract the bitter taste of various plant‐based medicines and beverages. Many countries have shown interest in its cultivation, and research activities have been initiated. Incorporation of this species in agricultural production systems, however, depends upon a thorough knowledge of the plant and its agronomic potential. The published literature on research and development of this crop is meager. The aim of this chapter is to describe the ecology, importance of the plant, and its production requirements, but major emphasis is given to the agronomic and management aspects of the plant to be grown as a crop. Further, this chapter represents an effort to compile the literature on S. rebaudiana and review the current status of understanding of the plant and its potential as an alternate source of cane sugar.
Rema Subhash - One of the best experts on this subject based on the ideXlab platform.
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in vitro antimicrobial activity of Stevia rebaudiana bertoni leaves
Tropical Journal of Pharmaceutical Research, 2007Co-Authors: Manish Tadhani, Rema SubhashAbstract:Purpose: The aim of the present study was to investigate antimicrobial activity of the various extracts of Stevia rebaudiana leaves. Method: Stevia rebaudiana Bertoni leaves were extracted in water, methanol, ethyl acetate and hexane and their antimicrobial activities were examined against few selected microorganisms including B. subtilis, S. aureus, M. luteus, S. marcenscens, P. aeruginosa, B. megaterium, E. coli, P. vulgaris, Yeast, A. niger and R. oligoporus using cup plate method. Results: Water extract of Stevia leaf showed activity against B. subtilis and S. aureus only. Methanol extract gave the highest zone of inhibition against P. aeruginosa whereas minimum zone of inhibition was found against S. aureus and yeast. B. megaterium and yeast were found to be highly susceptible towards ethyl acetate and hexane extracts, respectively whereas A. niger and B. subtilis were found to be least susceptible against ethyl acetate and hexane extracts, respectively. Hexane extract showed the highest activity against yeast among the tested microorganisms. Conclusion: The study confirms the possible antimicrobial potentiality of the leaf extract of Stevia rebaudiana.
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in vitro antioxidant activities of Stevia rebaudiana leaves and callus
Journal of Food Composition and Analysis, 2007Co-Authors: Manish Tadhani, Vinayak Patel, Rema SubhashAbstract:Abstract Leaf extract of Stevia rebaudiana promotes effects on certain physiological systems such as the cardiovascular and renal and influences hypertension and hyperglycemia. Since these activities may be correlated with the presence of antioxidant compounds, leaf and callus extracts of Stevia rebaudiana were evaluated for their total phenols, flavonoids content and total antioxidant capacity. Total phenols and flavonoids were analyzed according to the Folin–Ciocalteu method and total antioxidant activity of water and methanolic extracts of Stevia leaves and callus was assessed by ferric reducing/antioxidant power (FRAP) assay as well as 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The total phenolic compounds were found to be 25.18 mg/g for Stevia leaves and 35.86 mg/g for callus on dry weight basis. The flavonoids content was found to be 21.73 and 31.99 mg/g in the leaf and callus, respectively. The total antioxidant activity was expressed as mg equivalent of gallic acid, ascorbic acid, BHA and trolox per gram on dry weight basis. Total antioxidant activity found was ranged from 9.66 to 38.24 mg and 11.03 to 36.40 mg equivalent to different standards in water and methanolic extract of Stevia leaves, respectively. In case of Stevia callus, it was found to be 9.44 to 37.36 mg for water extract and 10.14 to 34.37 mg equivalent to standards for methanolic extract. The concentrations required for 50% inhibition (IC50) of DPPH radicals were 11.04, 41.04 and 57.14 μg/mL for gallic acid, trolox and butylated hydroxyanisole (BHA), respectively. The percent inhibition of DPPH radical of various extracts of Stevia leaves and callus found were ranged from 33.17% to 56.82%. The highest percent of inhibition was observed in methanolic extract of callus.
Incheol Jang - One of the best experts on this subject based on the ideXlab platform.
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overexpression of srdxs1 and srkah enhances steviol glycosides content in transgenic Stevia plants
BMC Plant Biology, 2019Co-Authors: Junshi Zheng, Ya Zhuang, Huizhu Mao, Incheol JangAbstract:Stevia rebaudiana produces sweet-tasting steviol glycosides (SGs) in its leaves which can be used as natural sweeteners. Metabolic engineering of Stevia would offer an alternative approach to conventional breeding for enhanced production of SGs. However, an effective protocol for Stevia transformation is lacking. Here, we present an efficient and reproducible method for Agrobacterium-mediated transformation of Stevia. In our attempts to produce transgenic Stevia plants, we found that prolonged dark incubation is critical for increasing shoot regeneration. Etiolated shoots regenerated in the dark also facilitated subsequent visual selection of transformants by green fluorescent protein during Stevia transformation. Using this newly established transformation method, we overexpressed the Stevia 1-deoxy-d-xylulose-5-phosphate synthase 1 (SrDXS1) and kaurenoic acid hydroxylase (SrKAH), both of which are required for SGs biosynthesis. Compared to control plants, the total SGs content in SrDXS1- and SrKAH-overexpressing transgenic lines were enhanced by up to 42–54% and 67–88%, respectively, showing a positive correlation with the expression levels of SrDXS1 and SrKAH. Furthermore, their overexpression did not stunt the growth and development of the transgenic Stevia plants. This study represents a successful case of genetic manipulation of SGs biosynthetic pathway in Stevia and also demonstrates the potential of metabolic engineering towards producing Stevia with improved SGs yield.
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Additional file 7: of Overexpression of SrDXS1 and SrKAH enhances steviol glycosides content in transgenic Stevia plants
2019Co-Authors: Junshi Zheng, Ya Zhuang, Huizhu Mao, Incheol JangAbstract:Figure S7. Monoterpenes extracted from Stevia plants overexpressing SrDXS1 (SrDXS1-OE). a-c α-pinene (a), β-pinene (b), and linalool (c), extracted from the leaves. All measurements are expressed as mean ± SE and statistical analysis was carried out using Student’s t-test (n = 5). (PDF 254 kb
