New Biotechnology · Volume 31S · July 2014 HIGH VALUE PLANT PRODUCTS

PL-04

In vivo and in vitro cultures of Lavandula angustifoliaMill. for essential oils production

Pana Lohasupthawee ∗ , Prangmas Srisurat

King Mongkut’s Institute of Technology Ladkrabang

The aim of this research was to extract the essential oils oflavender (Lavandula angustifolia Mill.) from callus culture, multipleshoots culture and hydroponic culture. The chemical composi-tion of each extract was analyzed by gas chromatography andmass spectrometry (GC-MS). In vitro culture of lavenders, multipleshoots were obtained in culture medium fortified with Murashigeand Skoog (MS) nutrients and 1.5 mg/l benzyladenine which pro-duced 12 shoots per explant. Callus was achieved by using leafexplants and showed best growth in MS medium supplementedwith 0.5 mg/l 2,4-dicholorophenoxyacetic acid. In vivo culture,hydroponic lavenders were achieved by using deep flow tech-nique system. The leaves and roots of hydroponic lavenders wereextracted for essential oils separately. The GC-MS results showedthat the leaves of hydroponic lavenders and in vitro shoots demon-strated the components of lavender essential oils whereas callusand roots of hydroponic lavenders showed no essential oils pro-duction.

http://dx.doi.org/10.1016/j.nbt.2014.05.2013

PL-05

Fermentative Nisin Production in Tofu for its Preserva-tion

Nicole Illas ∗ , Raphael Cziskus, Caterina Hünniger, Myriam Bello,Xuan Zhu, Markus Fischer, Bernward Bisping

University of Hamburg

Tofu has a high nutritional content and serves as stable food ineastern Asia. In developing countries pasteurization is not afford-able because tofu production takes place mostly in small factories.A cost-effective and natural preservation of tofu may be thenisinproduction in tofu cubes (2*2 cm) submerged in water by fer-mentation with Lactococcus lactis ssp. lactis DSM 20729. Optimalfermentation was conducted by adding 3.9% soy peptone. Further-more it could be shown that there is a non-uniform distributionof nisin in tofu cubes. The nisin concentration decreases fromthe surface to the interior of tofu but it was sufficient to extendthe shelf-life of tofu. Two methods for the detection of nisinin fermented tofu were tested. The comparison of an inhibitiontest (modified [1]), and LC-ESI-MS/MS method (based on ISO/TS27106:2009 [2]) illustrates that the detection limit of the inhibitiontest was significantly lower. Concentrations of 0.19 mg/kg nisin intofu and 0.06 mg/L in the supernatant could be determined. Thedetection limit for nisin using LC-ESI-MS/MS was 0.34 mg/kg intofu. Matrix calibration of the liquid substrate could not be car-ried out by LC-ESI-MS/MS, because the background noise of thematrix was too high.

It could be shown that the fermentation of tofu with L. lactis isan efficient and cost-effective alternative.

References

[1].Pongtharangkul T, Demirci A. Appl Microbiol Biotechnol:2004;65:268–72.

[2].International Organization for Standardization ISO/TS 27106Geneva Switzerland 2009.

http://dx.doi.org/10.1016/j.nbt.2014.05.2014

PL-06

Fermentation-like incubations of Theobroma cacao L. -Good quality in shorter time

Claudia Bahmann ∗ , Tumforde Thomas, Lieberei Reinhard

University of Hamburg

In the course of the post-harvest treatment of cocoa seeds (fer-mentation) the pulp is microbially degraded. During fermentationfirst ethanol, then acetic acid is produced in combination with atemperature increase. The conditions in the fermentation massentail the acidification of the cotyledon tissue and an extensiveproteolysis of storage proteins. The latter is carried out by endoge-nous proteases that are activated by acidic conditions. The cleavageactivity of the proteases as well as the conservative amino acidsequences of storage proteins provide a defined pattern of flavorprecursors of cocoa. In the study at hand seeds have been incu-bated under conditions analog to those of fermentation, becauseof the ability to control different parameters separately. Media withdifferent pH-values, all in the acid range, and different organicacids have been used. The basic effects of these factors on the seedwith regard to the proteolysis are examined. In order to imitate thetemperature conditions of fermentation, incubations are carriedout under different temperature sequences.

In the course of the incubation process comparatively higheramounts of the amino acids and phenolic compounds examinedare achieved already after three days. Comparable values in thefermentation procedures are achieved not until after six days. Thisillustrates the efficiency of the incubation procedure. In this study,an endogenic bioconversion has been proven to take place incocoa seeds in the course of incubations. Furthermore, the strivenaccumulation of characteristic chocolate aroma precursors can beinfluenced by processing seeds under defined external conditions.

http://dx.doi.org/10.1016/j.nbt.2014.05.2015

PL-07

Glucanocellulosic biomass: learning from marinebiomass to optimize terrestrial biomass conversion

Christian Voigt ∗ , Claudia Zwikowics

University of Hamburg

The recalcitrance of the plant cell wall is one of the obsta-cles in improving biomass conversion. We followed a strategy toenrich biomass with a polymer that is easily degradable and would

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HIGH VALUE PLANT PRODUCTS New Biotechnology · Volume 31S · July 2014

not impair the physiology of the plant. In marine biomass fromthe brown algae Fucus vesiculosus, the polymer (1,3)-β-glucan is amajor biomass component showing these characteristics and isalso present in terrestrial plants. We used this glucan-enriched,marine biomass to optimize hexose release and bioethanol produc-tion. The addition of a bacterial (1,3)-β-glucanase to a commercialenzyme cocktail as well as the usage of an optimized Saccharomycescerevisiae strain that we engineered for fermenting glucan-enrichedbiomass resulted in a 50% increase in bioethanol production. Totest the optimized processing of glucan-enriched biomass on ter-restrial biomass, we screened for plants with a high (1,3)-β-glucancontent and identified leaves from the energy crop Miscanthus xgiganteus with an exceptionally high (1,3)-β-glucan content of 5%.

Applying the optimized processing for glucan-enriched biomasson M. giganteus leaf biomass, we increased bioethanol productionby 13% compared to non-adapted conversion and fermentationstrategies. To further improve bioethanol production with thisadapted processing, we overexpressed a (1,3)-β-glucan synthasefrom Arabidopsis thaliana in M. giganteus, which further increased(1,3)-β-glucan content in leaf biomass to 8.5% and improvedbioethanol production by 20%. Our results suggest that generationof glucan-enriched biomass via synthetic biology approaches com-bined with optimized processing for glucanocellulosic bioethanolproduction is a promising alternative in increasing efficiency ofbiomass conversion.

http://dx.doi.org/10.1016/j.nbt.2014.05.2016

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