ABSTRACT
Actualmente, existe una necesidad en la industria alimentaria de buscar preservantes de origen natural que tengan una mejor aceptación por el consumidor. Una alternativa interesante que ha emergido en los últimos años es el uso de antimicrobianos naturales, los cuales además de ser efectivos en el control de microorganismos, son inocuos para la salud. La nisina es una bacteriocina producida por bacterias ácido lácticas que se utiliza actualmente como preservante en varios productos alimenticios. En Chile, el uso de la nisina como aditivo está restringido a quesos y cremas naturales o nata cuajada, pero existen otros alimentos que podrían beneficiarse del uso de este preservante, como es el caso de los aderezos tipo mayonesa vegetal. En el presente trabajo, se analiza de manera teórica, como el uso de nisina en estos aderezos impactaría el consumo máximo permitido para este aditivo en la población chilena. Para esto, se analizó cuál es el consumo teórico actual de nisina en Chile, y cómo este se vería afectado si se utilizara nisina como preservante en aderezos tipo mayonesa vegetal. Finalmente, los datos obtenidos se compararon con el valor de ingesta diaria admisible (IDA) para la nisina, evidenciándose que existe una ventana de oportunidad para el uso de nisina en otros productos alimenticios.
Currently, there is a need in the food industry for natural preservatives that have good consumers acceptance. Natural antimicrobials are a novel alternative, effective in controlling microbial growth, and safe to consume. Nisin is a bacteriocin produced by lactic acid bacteria that is currently used as a preservative in several food products. In Chile, nisin is regulated and restricted as an additive to cheeses and natural creams or curds. However, other food products could benefit from using nisin as a preservative, such as plant-based mayonnaise, where the consumer expects to find natural preservatives. In this review, we make a theoretical analysis of how adding nisin to plant-based mayonnaise would impact the daily intake of this additive in the Chilean population. Finally, we compare this data with the acceptable daily intake for nisin to conclude that there is an opportunity for using nisin as a preservative in plant-based mayonnaise without affecting consumers´ health.
ABSTRACT
BACKGROUND: One of the most extreme environments on our planet is the Maritime Antarctic territory, due to its low-water availability, which restricts the development of plants. Sanionia uncinata Hedw. (Amblystegiaceae), the main colonizer of the Maritime Antarctic, has effective mechanisms to tolerate this environment. It has been described that the tolerance to desiccation is mediated by the hormone abscisic acid (ABA), antioxidants systems, accumulation of compatible solutes and proteins of the late embryogenesis abundant (LEA). However, to date, these mechanisms have not been described in S. uncinata. Therefore, in this work, we postulate that the tolerance to desiccation in the Antarctic moss S. uncinata is mediated by the accumulation of ABA, the osmolytes proline and glycine betaine, and dehydrins (an LEA class 11 proteins). To demonstrate our hypothesis, S. uncinata was subjected to desiccation for 24 h (loss in 95% of water content), and the effects on its physiological, photosynthetic, antioxidant and biochemical parameters were determined. RESULTS: Our results showed an accumulation of ABA in response to water loss, and the activation of protective responses that involves an increment in levels of proline and glycine betaine, an increment in the activity of antioxidant enzymes such as SOD, CAT, APX and POD, and the accumulation of dehydrins proteins. CONCLUSION: The results showed, suggest that S. uncinata is a desiccation-tolerant moss, property mediated by high cellular plasticity regulated by ABA.
Subject(s)
Photosynthesis/physiology , Bryopsida/physiology , Desiccation , Antioxidants/analysis , Time Factors , Adaptation, Physiological , Bryopsida/classification , Bryopsida/chemistry , Antarctic RegionsABSTRACT
BACKGROUND: In field, C. quitensis Is subjected to many abiotic extreme environmental conditions, such as low temperatures, high UV-B, salinity and reduced water potentials, but not metal or metalloid high concentrations in soil, however, other members of Caryophyllaceae family have tolerance to high concentrations of metals, this is the case of Silene genre. In this work, we hypothesize that C. quitensis have the same mechanisms of Silene to tolerate metals, involving accumulation and induction of antioxidant systems, sugar accumulation and the induction of thiols such as phytochelatins to tolerate. RESULTS: The results showing an effective antioxidant defensive machinery involving non-enzymatic antioxidants such as phenolics, GSH and ascorbic acid, in another hand, GSH-related oligomers (phytochelatins) and sugars was induced as a defensive mechanism. CONCLUSIONS: Colobanthus quitensis exhibits certain mechanisms to tolerate copper in vitro demonstrating its plasticity to tolerate several abiotic stress conditions.