Arbutus unedo L. and Ocimum basilicum L. as sources of natural ingredients for bread functionalization

Mestrado com dupla diplomação com o High Institute of Biotechnology of Monastir (ISBM), TunisiaThe overwhelming growth of the world population is causing direct consequences on food demands, which has forced the food industry to apply synthetic additives in order to meet the needs of the consumer and ensuring the global quality of the food products including aspect, texture and flavor. However, due to the publication of some studies describing adverse effects associated with these synthetic additives, the natural ones have been gaining increasing interest. Arbutus unedo L. (strawberry tree) fruits and Ocimum basilicum L. (basil) leaves, are important sources of bioactive natural molecules. The aim of this work was to demonstrate the antioxidant potential (free radical scavenging effect, reducing power and inhibition of lipid peroxidation), antimicrobial (antibacterial using Gram-positive and Gram-negative strains and antifungal activity) and the absence of toxicity (porcine liver primary cells) of the ethanol extracts, obtained from the previously mentioned plants by using optimal conditions (23% of ethanol in A. unedo fruits; 80% of ethanol in O. basilicum leaves). Subsequently, the enriched extracts in catechin from A. unedo fruit and rosmarinic acid from O. basilicum leaves, were incorporated as natural ingredients in bread samples, with two objectives: to functionalize bread, introducing bioactive properties; and as natural ingredients with preservation capacity. Five groups of bread samples were prepared: i) control (without natural or synthetic additives); ii) bread incorporated with A. unedo fruit extract; iii) bread incorporated with O. basilicum leaves extract; iv) bread incorporated with ascorbic acid- E300 (natural additive); and v) bread incorporated with potassium sorbate - E202 (synthetic additive). Both extracts (A. unedo fruit and O. basilicum leaves) presented antioxidant activity (EC50 values lower the 595 and 351 μg/mL, respectively), without toxicity up to the maximal tested dose (400 μg/mL), and the main compounds present were catechin and rosmarinic acid, respectively. The breads enriched with the extracts obtained from O. basilicum leaves revealed the highest DPPH scavenging activity, showing to be more effective than ascorbic acid and potassium sorbate. Regarding reducing power all brad type’s revealed similar bioactivity. Some significant differences were observed for the color and nutritional parameters analyzed, and the bread with natural extracts showed lower values for color parameters (L* and a*) when compared to the breads with the chemical Abstract 11 additives. In relation to the nutritional parameters, higher values of water were observed in the breads with A. unedo fruits and ascorbic acid, whereas the higher values of fructose, energy and ash were attributed to the bread with O. basilicum leaves and potassium sorbate. Overall, the obtained results demonstrate that these extracts could be used in the development of new bread replacing the synthetic preservatives, without interfering with the physical and nutritional characteristics.The overwhelming growth of the world population is causing direct consequences on food demands, which has forced the food industry to apply synthetic additives in order to meet the needs of the consumer and ensuring the global quality of the food products including aspect, texture and flavor. However, due to the publication of some studies describing adverse effects associated with these synthetic additives, the natural ones have been gaining increasing interest. Arbutus unedo L. (strawberry tree) fruits and Ocimum basilicum L. (basil) leaves, are important sources of bioactive natural molecules. The aim of this work was to demonstrate the antioxidant potential (free radical scavenging effect, reducing power and inhibition of lipid peroxidation), antimicrobial (antibacterial using Gram-positive and Gram-negative strains and antifungal activity) and the absence of toxicity (porcine liver primary cells) of the ethanol extracts, obtained from the previously mentioned plants by using optimal conditions (23% of ethanol in A. unedo fruits; 80% of ethanol in O. basilicum leaves). Subsequently, the enriched extracts in catechin from A. unedo fruit and rosmarinic acid from O. basilicum leaves, were incorporated as natural ingredients in bread samples, with two objectives: to functionalize bread, introducing bioactive properties; and as natural ingredients with preservation capacity. Five groups of bread samples were prepared: i) control (without natural or synthetic additives); ii) bread incorporated with A. unedo fruit extract; iii) bread incorporated with O. basilicum leaves extract; iv) bread incorporated with ascorbic acid- E300 (natural additive); and v) bread incorporated with potassium sorbate - E202 (synthetic additive). Both extracts (A. unedo fruit and O. basilicum leaves) presented antioxidant activity (EC50 values lower the 595 and 351 μg/mL, respectively), without toxicity up to the maximal tested dose (400 μg/mL), and the main compounds present were catechin and rosmarinic acid, respectively. The breads enriched with the extracts obtained from O. basilicum leaves revealed the highest DPPH scavenging activity, showing to be more effective than ascorbic acid and potassium sorbate. Regarding reducing power all brad type’s revealed similar bioactivity. Some significant differences were observed for the color and nutritional parameters analyzed, and the bread with natural extracts showed lower values for color parameters (L* and a*) when compared to the breads with the chemical Abstract 11 additives. In relation to the nutritional parameters, higher values of water were observed in the breads with A. unedo fruits and ascorbic acid, whereas the higher values of fructose, energy and ash were attributed to the bread with O. basilicum leaves and potassium sorbate. Overall, the obtained results demonstrate that these extracts could be used in the development of new bread replacing the synthetic preservatives, without interfering with the physical and nutritional characteristics

Arbutus unedo L. and Ocimum basilicum L. as sources of natural preservatives for food industry: A case study using loaf bread

The aim of this work was to demonstrate the antioxidant potential, antimicrobial and the absence of toxicity of the ethanol extracts obtained from strawberry tree fruits and basil leaves, using optimal conditions. Subsequently, the extracts rich in catechin, from strawberry tree fruits, and rosmarinic acid from basil leaves, were incorporated as natural ingredients in loaf bread samples, with two objectives: to functionalize bread, introducing bioactive properties; and as natural ingredients with preservation capacity. Three more groups: control (without addition of any additive), bread incorporated with ascorbic acid - E300 and bread incorporated with potassium sorbate - E202 and for each group were 3 different times were analyzed: immediately after incorporation and after 3 and 7 days. Both natural extracts presented antioxidant activity, without toxicity up to the maximal tested dose (400 µg/mL), and the main compounds present were catechin and rosmarinic acid, respectively. The breads incorporated with the natural extracts, especial b asil, presented a higher antioxidant capacity than the loaf breads incorporated with ascorbic acid and potassium sorbate. Overall, the obtained results demonstrate that these extracts could be used in the development of new bread replacing the synthetic preservatives, without interfering with nutritional characteristics.info:eu-repo/semantics/publishedVersio

Arbutus unedo L. and Ocinum basilicum L. as sources of natural ingredients for bread functionalization

The overwhelming growth of the world population is causing direct consequences on food demands, which has forced the food industry to apply synthetic additives in order to meet the needs of the consumer and ensuring the global quality of the food products including aspect, texture and flavor. However, due to the publication of some studies describing adverse effects associated with these synthetic additives, the natural ones have been gaining increasing interest. Arbutus unedo L. (strawberry tree) fruits and Ocimum basilicum L. (basil) leaves, are important sources of bioactive natural molecules, especially phenolic compounds, including flavan-3- ols and phenolic acids, respectively . The aim of this work was to demonstrate the antioxidant potential (free radical scavenging effect, reducing power and inhibition of lipid peroxidation) and the absence of toxicity (porcine liver primary cells) of ethanol extracts, obtained from the previously mentioned plants by using optimal conditions. Subsequently, the extracts were incorporated as natural ingredients in loaf bread samples, with two objectives: to functionalize loaf bread, introducing bioactive properties; and as natural ingredients with preservation capacity. Five groups of loaf bread samples were prepared: i) control (without natural or synthetic additives); ii) loaf bread incorporated with strawberry tree extract; iii) loaf bread incorporated with basil extract; iv) loaf bread incorporated with ascorbic acid- E300 (natural additive); and v) loaf bread incorporated with potassium sorbate- E202 (synthetic additive). Both extracts (strawberry tree fruits and basil leaves) presented antioxidant activity (EC50 values lower the 595 and 351 μg/mL, respectively), without toxicity up to the maximal tested dose, and the main compounds present were (+)-catechin and rosmarinic acid, respectively. The introduction of both natural and synthetic additives in loaf bread when compared to the control sample, did not cause significant changes, neither in pH values, nor in color or any of the evaluated nutritional parameters. The obtained results demonstrate that these extracts could be used in the development of new loaf bread replacing the synthetic preservatives, without interfering with the physical and nutritional characteristics.info:eu-repo/semantics/publishedVersio

Rbutus unedo L. and Ocimum basilicum L. as natural preservers of bread

Atualmente, existe uma preocupação da indústria alimentar na substituição de aditivos sintéticos por ingredientes naturais. Os extratos naturais obtidos a partir de plantas surgem como possíveis alternativas aos conservantes sintéticos, nomeadamente dos antioxidantes. Neste trabalho, pretendeu-se comprovar a eficácia de extratos ricos em catequina, obtido a partir de frutos de Arbutus unedo L. (medronho) e em ácido rosmarínico obtido a partir de folhas de Ocimum basilicum L. (manjericão), como conservantes naturais de pão, comparando a sua eficácia com aditivos sintéticos normalmente aplicados a produtos de panificação. Após a avaliação das propriedades antioxidantes (valores EC50 do efeito bloqueador de radicais de DPPH = 595 e 351 μg/ mL, para medronho e manjericão, respetivamente) e antimicrobianas (contra 8 bactérias e 8 fungos) e confirmação da ausência de citoxicidade (numa cultura primária de células de fígado), os extratos ricos em (+)-catequina e ácido rosmarínico foram incorporados no pão. O seu efeito foi comparado com o ácido ascórbico (E300), o sorbato de potássio (E202) e com uma amostra controlo (pão sem aditivos) imediatamente após a incorporação e após 3 e 7 dias de armazenamento, à temperatura ambiente e protegidos da luz. Os pães aditivados com os extratos naturais, especialmente de manjericão, apresentaram maior capacidade antioxidante do que os pães com ácido ascórbico e sorbato de potássio, tendo todos mantido as suas propriedades nutricionais. Em geral, os resultados obtidos demonstraram que os extratos podem ser utilizados no desenvolvimento de pão, substituindo os conservantes sintéticos, sem interferir nas características físicas e nutricionais dos produtos finais.Currently, the food industry is focused on replacing synthetic additives with natural ingredients. Natural extracts obtained from plants have emerged as possible alternatives to synthetic preservatives, namely in the class of antioxidants. In this work we intend to prove the efficacy of an extract rich in catechin, obtained from Arbutus unedo L. (strawberry tree) fruits, and of an extract rich in rosmarinic acid obtained from Ocimum basilicum L. (basil) leaves, as natural preservatives of bread and compare these results to synthetic additives which are normally used in bakery products. After evaluation of the antioxidant (EC50 values for DPPH scavenging activity = 595 and 351 μg/ mL, for strawberry tree fruits and basil leaves, respectively) and antimicrobial (against 8 bacteria and 8 fungi food contaminants) properties, and confirmation of cytotoxicity absence (in porcine liver primary cells), the extracts rich in (+)-catechin and rosmarinic acid were incorporated into the bread. Its effect was compared to ascorbic acid (E300), potassium sorbate (E202) and to a control sample (bread without additives), immediately after incorporation and in the 3rd and 7th day of storage, protected from light at room temperature. The breads incorporated with the natural extracts, especial basil, presented a higher antioxidant capacity than the breads incorporated with ascorbic acid and potassium sorbate, while the nutritional profile was not affected. Overall, the obtained results demonstrate that these extracts could be used in the development of new bread formulations replacing the synthetic preservatives, without interfering with the physical and nutritional characteristics of the final product.info:eu-repo/semantics/publishedVersio