• Journal of Plant Biotechnology
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• v.45 no.1
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• pp.63-70
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• 2018

Brazzein is the smallest sweet protein and was isolated from the fruit pulp of Pentadiplandra brazzeana Baillon, native to tropical Africa. From ancient times, the indigenous people used this fruit in their diet to add sweetness to their daily food. Brazzein is 500 to 2000 times sweeter than sucrose on a weight basis and 9500 times sweeter on a molar basis. This unique property has led to increasing interest in this protein. However, it is expensive and difficult to produce brazzein other than in its native growing conditions which limits its availability for use as a food additive. In this study, we report high production yields of, brazzein protein in transgenic rice plants. An ORF region encoding brazzein and driven by the $2{\times}CaMV\;35S$ promoter was introduced into rice genome (Oryza sativa Japonica) via Agrobacterium-mediated transformation. After transformation, 17 regenerated plant lines were obtained and these transgene-containing plants were confirmed by PCR analysis. In addition, the selected plant lines were analyzed by Taqman PCR and results showed that 9 T0 lines were found to have a single copy out of 17 transgenic plants. Moreover, high and genetically stable expression of brazzein was confirmed by western blot analysis. These results demonstrate that recombinant brazzein was efficiently expressed in transgenic rice plants, and that we have developed a new rice variety with a natural sweetener.

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4106-4108
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• 2011

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3353-3356
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• 2014

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3830-3833
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• 2010

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.257-265
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• 2018

Sweetener is one of the additives that makes you feel sweet. Artificial sweeteners and sugar are typical examples, and sweetness proteins with sweetness characteristics have been widely studied. These studies elucidated the transformation lettuce cells with Agrobacterium method for stable production of natural sweet proteins, brazzein, thaumatin, and miraculin. In this paper, we report use of a plant expression system for production of sweet proteins. A synthetic gene encoding sweet proteins was placed under the control of constitutive promoters and transferred to lettuce. High and genetically stable expression of sweetener was confirmed in leaves by RT-PCR and Western blot analysis. Sweet proteins expressed in transgenic lettuce had sweetness-inducing activity. Results demonstrate recombinant sweet proteins correctly processed in transgenic lettuce plants, and that this production system could be a viable alternative to production from the native plant.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.397-404
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• 2016

Sweet and taste modifying proteins are natural alternatives to synthetic sweeteners and flavor enhancers, and have been used for centuries in different countries. Use of these proteins is limited due to less stability and availability. However, recent advances in biotechnology have enhanced their availability. These include production of sweet and taste modifying proteins in transgenic organisms, and protein engineering to improve their stability. Their increased availability in the food, beverage or medicinal industries as sweeteners and flavor enhancers will reduce the dependence on artificial alternatives. Production of transgenic plants using sweet and taste modifying genes, is an interesting alternative to the extraction of these products from natural source. In this review paper, we briefly describe various sweet and taste modifying proteins (such as thaumatin, monellin, brazzein, curculin and miraculin), their properties, and their application for plant development using biotechnological approaches.