Lactic acid fermentation as a tool to enhance the antioxidant properties of Myrtus communis berries

Background: Myrtle (Myrtus communis L.) is a medicinal and aromatic plant belonging to Myrtaceae family, which is largely diffused in the Mediterranean areas and mainly cultivated in Tunisia and Italy. To the best of our knowledge, no studies have already considered the use of the lactic acid fermentation to enhance the functional features of M. communis. This study aimed at using a selected lactic acid bacterium for increasing the antioxidant features of myrtle berries, with the perspective of producing a functional ingredient, dietary supplement or pharmaceutical preparation. The antioxidant activity was preliminarily evaluated through in vitro assays, further confirmed through ex vivo analysis on murine fibroblasts, and the profile of phenol compounds was characterized. Results: Myrtle berries homogenate, containing yeast extract (0.4%, wt/vol), was fermented with Lactobacillus plantarum C2, previously selected from plant matrix. Chemically acidified homogenate, without bacterial inoculum and incubated under the same conditions, was used as the control. Compared to the control, fermented myrtle homogenate exhibited a marked antioxidant activity in vitro. The radical scavenging activity towards DPPH increased by 30%, and the inhibition of linoleic acid peroxidation was twice. The increased antioxidant activity was confirmed using Balb 3 T3 mouse fibroblasts, after inducing oxidative stress, and determining cell viability and radical scavenging activity through MTT and DCFH-DA assays, respectively. The lactic acid fermentation allowed increased concentrations of total phenols, flavonoids and anthocyanins, which were 5–10 times higher than those found for the non-fermented and chemically acidified control. As shown by HPLC analysis, the main increases were found for gallic and ellagic acids, and flavonols (myricetin and quercetin). The release of these antioxidant compounds would be strictly related to the esterase activities of L. plantarum. Conclusions: The lactic acid fermentation of myrtle berries is a suitable tool for novel applications as functional food dietary supplements or pharmaceutical preparations

Microbial production of ellagic acid and biodegradation of ellagitannins

In the last years, tannin biodegradation has been the subject of a lot of studies due to its commercial importance and scientific relevance. Tannins are molecules of low biodegradation and represent the main chemical group of natural anti-microbials occurring in the plants. Among the different kinds of tannins, ellagitannins represent the group less studied manly due to their diversity and chemical complexity. The general outline of this work includes information on tannins, their classification and properties, biodegradation, ellagic acid production, and potential applications. In addition, it describes molecular, catalytic, and functional information. Special attention has been focused on the biodegradation of ellagitannins describing the possible role of microbial enzymes in the production of ellagic acid

Extraction and analysis of ellagic acid from novel complex sources

Ellagic acid (EA) was quantified by reversed-phase high-performance liquid chromatography (RP-HPLC) coupled with photodiode array detection (DAD) in five fine-powdered plants collected from the semiarid region of Mexico. Samples analysed included Jatropha dioica branches (Dragon's blood), Euphorbia antisyphyllitica branches (Candelilla), Turnera diffusa Willd leaves (Damiana), Flourensia cernua leaves (hojasen) and Punica granatum husk (pomegranate) at two maturity stages ("turning" or intermediate and maturated fruit, considered as positive controls). The results demonstrated high EA concentrations in all tested samples which are novel sources of this natural antioxidant. The method developed for the EA analysis is fast and it showed an excellent linearity range, repeatability, intra-and inter-day precision and accuracy with respect to the methods reported for the EA analysis

Guar Gum as an Edible Coating for Enhancing Shelf-Life and Improving Postharvest Quality of Roma Tomato ( Solanum lycopersicum

There exists an increasing interest from consumers and scientific community in developing edible-natural-biodegradable coatings to replace commercial wax-based coatings for maintaining postharvest quality of vegetables. In this work, the effectiveness of guar gum coating on various quality characteristics of Roma tomato at 22±2°C over a 20 d storage period was investigated. Tomatoes were covered with a 1.5% guar gum coating plasticized with glycerol at 30% and stored at 22±2°C and 40% RH for 20-d. Tomatoes covered with edible coating significantly enhanced firmness and reduced weight loss, delayed changes on soluble-solids-content, retarded loss of total acidity, and decreased respiration rate compared with uncoated-control fruit. Sensory analysis by trained panelists revealed that the use of the edible coating influenced the acceptability of tomatoes. There were significant differences on the scores given by panelists when comparing the coated and uncoated tomatoes. It was concluded that guar gum affected favorably the physicochemical, microbial, and sensorial quality properties of Roma tomato and therefore could be beneficial in delaying the ripening process at 22±2°C

Advantages and Progress Innovations of Solid-State Fermentation to Produce Industrial Enzymes

Industrial enzymes are biocatalysts that are commercially used in a variety ofcommercial sectors such as pharmaceuticals, chemical production, biofuels, food and beverages, and consumer products. Due to advancements in recentyears, biocatalysts are considered more economical than use of whole cells andcan be used as a unit operation within a process to generate the desired productof interest. Industrial biological catalysis through enzymes has experienced rapidgrowth in recent years due to their ability to operate at mild conditions, highspecificity, and high productivity. Industrial enzymes can be produced by bothsubmerged fermentation (SmF) and solid-state fermentation (SSF). In contrast tothe first process, the second bioprocess (SSF) is the cultivation of microorganismsunder controlled conditions in the absence of free water. Examples of bioproductsof SSF include industrial enzymes, fuels, and nutrient-enriched animalfeeds. Most industrial enzymes are manufactured using the traditional bioprocessof SmF, where microbial cells are suspended in a large volume of water thatis stirred and aerated using mechanical devices; such culture conditions dictatethe overall physiological behavior of microorganisms provoking biochemicaland structural changes affecting the quantity and activity of biocatalysts produced.Among the main advantages of SSF over SmF is a higher volumetricproductivity, secretion facilities to get extracellular bioproducts with higher stability,being usually simpler with lower energy requirements, resembling of thenatural habitat of some microorganisms, and easier downstream processing. Inthis chapter we summarize, compare, analyze, and discuss the technological,biochemical, and microbiological advantages of SSF to produce industrialenzymes. Furthermore, culture conditions, aggregation and diffusional phenomena,bioreactors, genetic expression, and protein regulation are covered.Fil: Londoño Hernandez, Liliana. Universidad Autonoma de Coahuila; MéxicoFil: Ruiz, Héctor A.. Universidad Nacional Autonoma de Mexico. Colegio de Ciencia y Tecnología; MéxicoFil: Ramírez Toro, Cristina. Universidad del Valle; ColombiaFil: Ascacio Valdes, Alberto. Universidad Autónoma de Coahuila; MéxicoFil: Rodriguez Herrera, Raúl. Universidad Autónoma de Coahuila; MéxicoFil: Aguilera Carbo, Antonio. Universidad Autónoma Agraria Antonio Narro; MéxicoFil: Tubio, Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Químicos Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Procesos Biotecnológicos y Químicos Rosario; ArgentinaFil: Picó, Guillermo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Químicos Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Procesos Biotecnológicos y Químicos Rosario; ArgentinaFil: Prado Barragan, Arely. Universidad Autónoma Metropolitana; MéxicoFil: Gutierrez Sanchez, Gerardo. Georgia State University; Estados UnidosFil: Aguilar, Cristóbal Noé. Universidad Autónoma de Coahuila; Méxic