Percorrer por autor "Bachari, Khaldoun"
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- Bioactive properties of bio-residues from food industry: pumpkin seeds, peels, and fibrous strandsPublication . Leichtweis, Maria Gabriela; Molina, Adriana K.; Pereira, Carla; Pires, Tânia C.S.P.; Bachari, Khaldoun; Ziani, Borhane E.C.; Ferreira, Isabel C.F.R.; Barros, LillianThe limitation of natural resources, together with current consumer trends and needs, demand the implementation of sustainable food systems, able to produce healthier products and fulfil circular economy principles. The food industry is under pressure to offer healthy, convenient, and ready-to-eat foods, able to meet daily nutritional needs, provide pleasure and satiety, and attend to consumers’ growing expectations and safety issues [1]. Given its high nutritional value, pumpkin is one of the most important sources of sustenance of the poorest regions in the world. Nevertheless, during the industrial processing of this fruit, about 25% of the pumpkin is wasted, being this by-product mainly constituted by peels, seeds, and fibrous strands [2]. Through the present work, these bio-residues were assessed in terms of bioactive properties, namely the lipid peroxidation inhibition capacity (TBARS) and the anti-hemolytic activity (OxHLIA), as also the cytotoxicity against a primary culture of non-tumor porcine liver cells (PLP2), by the sulforodamine B assay. Three pumpkin varieties grown in Algeria were studied, namely Cucurbita pepo (common pumpkin), Cucurbita moschata (butternut squash), and Cucurbita moschata (Musquée de Provence). Regarding the antioxidant activity, in the TBARS assay, the seeds stood out for all the varieties, with the best result being presented by the common pumpkin. The seeds of this variety showed an IC50 value of about 1.5 times lower than that of the positive control, Trolox. On the other hand, in the OxHLIA assay, the results were quite similar between the type of bioresidues and between the varieties. Despite their strong lipid peroxidation inhibition capacity, the seeds of the common pumpkin did not present anti-hemolytic properties. Regarding cytotoxicity, the effect of inhibiting non-tumor cell growth was not observed, even at the highest tested concentration (400 μg/mL), which is of great importance in food safety. These preliminary results are the basis for future studies aiming at the valorization of bioresidues from food industry, allowing its application as food additives, for preservative purposes.
- Biological activity of pumpkin byproducts: antimicrobial and antioxidant propertiesPublication . Leichtweis, Maria Gabriela; Molina, Adriana K.; Pires, Tânia C.S.P.; Dias, Maria Inês; Calhelha, Ricardo C.; Bachari, Khaldoun; Ziani, Borhane E.C.; Oliveira, Beatriz; Pereira, Carla; Barros, LillianPumpkin fruits are widely appreciated and consumed worldwide. In addition to their balanced nutritional profile, pumpkin species also present valuable bioactive compounds that confer biological and pharmacological properties to them. However, the seeds, peels, and fibrous strands resulting from pumpkin processing are still poorly explored by the food industry. The current study used those fruit components from the genotypes of pumpkin that are economically significant in Portugal and Algeria to produce bioactive extracts. In order to support their usage as preservatives, their phenolic content (HPLC-DAD-ESI/MS) and antioxidant (OxHLIA and TBARS) and antimicrobial properties (against eight bacterial and two fungal strains) were assessed. In terms of phenolic profile, the peel of the Portuguese ‘Common Pumpkin’ showed the most diversified profile and also the highest concentration of total phenolic compounds, with considerable concentrations of (-)-epicatechin. Regarding the antioxidant capacity, the seeds of ‘Butternut Squash’ from both countries stood out, while the fibrous strands of Portuguese ‘Butternut Squash’ and the seeds of Algerian ‘Gold Nugget Pumpkin’ revealed the strongest antimicrobial activity. The bioactive compounds identified in the pumpkin byproducts may validate their enormous potential as a source of bio-based preservatives that may enhance consumers’ health and promote a circular economy.
- Caracterização fenólica (HPLC-DAD-ESI/MS) e bioativa de extratos ricos em moléculas conservantesPublication . Leichtweis, Maria Gabriela; Molina, Adriana K.; Pereira, Carla; Pires, Tânia C.S.P.; Dias, Maria Inês; Bachari, Khaldoun; Ziani, Borhane E.C.; Oliveira, Beatriz; Ferreira, Isabel C.F.R.; Barros, LillianCom o intuito de valorizar subprodutos industriais e promover processos sustentáveis, o presente trabalho teve como objetivo explorar as cascas, sementes e fibras resultantes do processamento da abóbora como fonte de compostos bioativos com capacidade conservante. Assim, foram avaliados os subprodutos de três variedades cultivadas na Argélia, nomeadamente ‘Gold nugget pumpkin’, ‘Butternut Squash’ e ‘Musqueé de Provence’. A composição fenólica foi avaliada por HPLC-DAD-ESI/MSe o potencial conservante dos extratos foi demonstrado através da análise da atividade antioxidante, por dois métodos biológicos (TBARS e OxHLIA), e antimicrobiana, contra oito estirpes de bactérias e duas de fungos. Todas as amostras apresentaram capacidade de inibição microbiana e elevada atividade antioxidante, com destaque para as sementes, especialmente da variedade ‘Gold nugget pumpkin’ que apresentou um valor de IC50 inferior ao do controlo positivo Trolox no ensaio TBARS. As sementes também apresentaram melhor atividade antibacteriana do que os restantes subprodutos, protegendo contra sete das oito estirpes bacterianas testadas, na concentração máxima de 10 mg/mL. Relativamente ao perfil fenólico, conforme apresentado na Figura 1, foram tentativamente identificados sete compostos, sendo estes o flavan-3-ol (-)-epicatechin ([M-H]- at m/z 289; pico 1), o ácido cítrico ([M-H]- at m/z 191; pico 2), o ácido fenólico 4-O-(6′-O-glucosyl-4″-hydroxybenzoyl)-4- hydroxybenzyl alcohol ([M-H]- at m/z 405; pico 3), e quatro flavonoides nos restantes picos. Curiosamente, as cascas e as fibras apresentaram maior quantidade e heterogeneidade de compostos fenólicos totais do que as sementes. Estes resultados provam o potencial dos subprodutos de abóbora como fontes económicas e promissoras de compostos conservantes, favorecendo processos industriais mais sustentáveis.
- Detailed chemical composition and functional properties of Ammodaucus leucotrichus Cross. & Dur. and Moringa oleifera LamarckPublication . Ziani, Borhane E.C.; Rached, Wahiba; Bachari, Khaldoun; Alves, Maria José; Calhelha, Ricardo C.; Barros, Lillian; Ferreira, Isabel C.F.R.Edible Ammodaucus leucotrichus Cross. & Dur. and Moringa oleifera Lamarck are largely used in the Algerian Sahara. In this context, soluble sugars, fatty acids, organic acids, and tocopherols were characterized. Decoctions and hydroethanolic extracts were studied regarding their phenolic compounds by HPLC-DAD-ESI/MSn, and in-vitro cytotoxic, anti-inflammatory, and antibacterial activities were evaluated. Results indicate high contents of carbohydrates (glucose and sucrose) and significant levels of protein and mineral were recorded for both plants. Malic acid was the major organic acid alongside with α-tocopherol, while PUFA was predominant in M. oleifera and MUFA in A. leucotrichus. Flavonoid derivatives were the most abundant group, being luteolin-O-(malonyl-glucoside) the main compound in A. leucotrichus and quercetin-3-O-(6″-malonyl-glucoside) and 3-O-caffeoylquininc acid the major molecules in M. oleifera. Extracts exhibited significant cytotoxicity on Hela and MCF-7 cell lines. The anti-inflammatory activity was also higher in the hydroethanolic extracts, which also revealed the highest antibacterial effects, especially for Gram-positive bacteria.
- Evaluation of the phenolic profile and bioactive potential of portuguese and Algerian pumpkin by-productsPublication . Leichtweis, Maria Gabriela; Molina, Adriana K.; Pires, Tânia C.S.P.; Dias, Maria Inês; Calhelha, Ricardo C.; Bachari, Khaldoun; Ziani, Borhane E.C.; Oliveira, Beatriz; Pereira, Carla; Barros, LillianPumpkin, a globally appreciated fruit, possesses a balanced nutritional profile and valuable biological and pharmacological properties. However, currently, the industrial processing of this fruit still focuses on the pulp, while large volumes of by-products are wasted. Considering the potential content of high value-added compounds in this fruit parts, like seeds and peel [1], the present study proposed the seeds, peel, and fibrous strands from three different genotypes that are economically significant in Portugal and Algeria to produce bioactive extracts. In order to support their usage as preservatives, their phenolic content and bioactivity were assessed. The hydroethanolic extracts (80:20 ethanol/water) were obtained by maceration, and their phenolic profile was analyzed by HPLC-DAD-ESI/MS, with a tentative identification followed by quantification. Also, the antioxidant properties were assessed through two cell based assays (OxHLIA and TBARS) and the antimicrobial capacity was tested against eight bacterial and two fungal strains. In terms of phenolic profile, eight compounds were found, six of which belonging to the flavonoid family. The Portuguese ‘Common Pumpkin’ peel showed the most diversified profile and also the highest concentration of total phenolic compounds (9.4 ± 0.3 mg/g), with considerable concentrations of (-)-epicatechin (4.58 ±0.08 mg/g). Despite the different phenolic composition, all samples presented relevant bioactive properties. Regarding the antioxidant capacity, the seeds of ‘Butternut Squash’ from both countries stood out, while the fibrous strands of Portuguese ‘Butternut Squash’ and the seeds of Algerian ‘Gold Nugget Pumpkin’ revealed the strongest antimicrobial activity. In addition, the potential safety of the extracts was verified, where none of the samples showed toxicity against a primary culture of non-tumor porcine liver cells (PLP2) up to 400 g/mL. The identification of bioactive compounds in pumpkin byproducts highlights their significant potential as a source of bio-based preservatives, which can promote consumers’ health and contribute to a circular economy.
- Food preservative extracts from pumpkin by-productsPublication . Molina, Adriana K.; Leichtweis, Maria Gabriela; Pereira, Carla; Pires, Tânia C.S.; Calhelha, Ricardo C.; Bachari, Khaldoun; Ziani, Borhane E.C.; Ferreira, Isabel C.F.R.; Barros, LillianPumpkin is a vegetable widely consumed around the world, popularly known for its nutritional and pharmacological properties. Some reports in the literature reveal the rich profile of nutrients and bioactive compounds of pumpkin varieties [1,2]. However, the seeds, peels, and fibers resulting from pumpkin processing are still poorly explored by food industry. Considering the alarming scenario of losses and waste during all the food supply chain worldwide [3] and seeking to promote a more sustainable food system, the present study purposed to investigate the by-products of different varieties of pumpkin as a source of extracts with preservative capacity for food application. For that purpose, hydroethanolic extracts from the varieties “Butternut squash”, “Common pumpkin”, and “Kabocha squash” from Portugal, and “Butternut squash”, “Common pumpkin”, and “Musquée de provence” from Algeria, were evaluated in terms of their bioactivities, more specifically the antioxidant, antimicrobial, and cytotoxic capacities. All the samples presented great antioxidant capacity through two based-cell assays, namely the lipid peroxidation inhibition capacity (TBARS) and the anti-hemolytic activity (OxHLIA). Interestingly, the seeds of the common pumpkin from Algeria did not present antihemolytic properties, despite showing the strongest lipid peroxidation inhibition capacity. In fact, the seeds stood out for all the pumpkin varieties in the TBARS assay, while in the OxHLIA assay, the results were quite similar between the type of bioresidues and between the varieties. Moreover, the samples from Portugal showed greater antioxidant capacity than the Algerian ones. Regarding cytotoxicity, the effect of inhibiting non-tumor cell growth was not observed, even at the highest tested concentration of 400 μg/mL. This first validation is of great importance to prevent food safety issues. These preliminary results are the basis for future studies aiming at the valorization of these bioresidues from food industry as a great source of preservative compounds toward the replacement of synthetic additives with natural alternatives allied to health benefits, as also the promotion of a circular economy
- Hemi-synthesis of novel (S)-carvone hydrazone from Carum carvi L. essential oils: structural and crystal characterization, targeted bioassays and molecular docking on human protein kinase (CK2) and Epidermal Growth factor Kinase (EGFK)Publication . Tedjini, Rima; Ziani, Borhane E.C.; Casimiro, Teresa; Viveiros, Raquel; Calhelha, Ricardo C.; Barros, Lillian; Boukenna, Leila; Hamdi, Abderrezak; Chebout, Redouane; Bachari, Khaldoun; Talhi, Oualid; Silva, ArturPolyfunctional N,O,O,N-type ligands such as the oxalyl dihydrazide (ODH) may induce formation of mono- , di-, and polynuclear complexes with natural monoterpene ketones, involving ligand bridging and Oxo- bridging. In this context, a novel chiral dihydrazone is designed through hemi-synthesis process by re- acting oxalyldihydrazide (ODH) with ( s )-carvone, the major compound of caraway’s seeds essential oil. The C = N imine bi-condensation is performed without prior isolation of the natural ( s )-carvone and the resulting ( s )-carvone dihydrazone (s-CHD) is structurally characterized by Single-crystal X-ray diffrac- tion, 2D-NMR spectroscopy and chiral LCMS analysis to confirm the formation of a single pure enan- tiomer. In -vitro cell-based assays were conducted on normal fibroblast (L929) using a presBlue (PB) flu- orescence quantification method of cell-viability and by sulforhodamine B calorimetric cytotoxicity as- says to determine the anti-proliferative effect on four human tumoral lines (NCI-H460, Hela, HepG2 and MCF-7) and normal PLP2. Anti-inflammatory assays were determined through NO production by Maurine LPS-stimulated macrophages (RAW 264.7). The ( s )-CHD has no effect on normal cells viability ( > 88%) and PLP2 (GI50 = 326 ug/mL), while a moderate ( ∼55%) to significant ( ∼63%) antigrowth potential was recorded against HepG2, Hela and MCF-7 tumor cell lines, where RAW 264.7 was feebly sensitive. A molecular docking was performed using Autodock vina software on the protein kinase CK2 and Epi- dermal Growth factor Kinase proteins EGFK and the dock scores allowed to identify significant bind- ing affinities (lower G and Ki values) and potential hydrophilic/hydrophobic interactions with ( s )-CHD comparing to the clinical ellipticine as potential ligands. Molecular docking suggests that ( s )-CHD pos- sesses high affinity towards the kinase domain receptors CK2 and EGFR, being able to bind to the ATP region.
- Infusions obtained from two medicinal plants as a source of polyphenols with antibacterial activityPublication . Ziani, Borhane E.C.; Barros, Lillian; Boumehira, Ali Zineddine; Bachari, Khaldoun; Heleno, Sandrina A.; Alves, Maria José; Ferreira, Isabel C.F.R.Several researches are now oriented towards studying natural molecules of plant origin. In Algeria, many herbs are used as traditional remedies to treat different diseases. In this context, the phenolic compounds of the aqueous extracts, obtained by infusion, of two plant species, Saccocalyx satureioides Coss.& Dur and Limoniastrum guyonianum Boiss., from the Algerian flora, were identified and quantified by HPLC-DADESI/ MS, and their antibacterial activity was evaluated against clinical isolates. The results indicate the presence of several phenolic acids, in particular, derivatives of caffeic acid with glycosylated flavonoids. While for S. satureioides 13 phenolic compounds were identified and the rosmarinic acid was the most abundant phenolic acid, L. guyonianum showed a high abundance of myricetin and derivatives such as myricetin-3-O-glucoside and myricetin-O-rhamnoside among the eight molecules detected. The antibacterial activity of the infusions was significant with MIC values between 2.5 and 20 mg/mL, however, L. guyonianum had the highest activity on all the tested bacteria. Staphylococcus aureus and Pseudomonas aeruginosa were the most sensitive and the most resistant strains, respectively. Consequently, the studied plant species are sources of natural antibacterial substances that can be used to fight against pathogenic microorganisms.
- Natural compounds with preservative capacity obtained from by-products of pumpkin industrial processingPublication . Leichtweis, Maria Gabriela; Molina, Adriana K.; Pereira, Carla; Dias, Maria Inês; Pires, Tânia C.S.P.; Calhelha, Ricardo C.; Bachari, Khaldoun; Ziani, Borhane E.C.; Oliveira, Beatriz; Ferreira, Isabel C.F.R.; Barros, LillianThe search for cheap and suitable sources of natural compounds with functional properties as an alternative for the replacement of synthetic additives is growing. Part of this occurs in the food industry, which is under pressure to offer healthier products, but still convenient and durable. However, great potential can be found inside the industry itself, once large amounts of fruits and vegetables are discarded during food processing. These wastes comprise leaves, seeds, skin, bagasse, and juices, which are rich in high value-added compounds that present functional and bioactive properties.The present work purposed to explore the by-products of pumpkin industrial processing as source of natural compounds with preservative capacity for food application. For this purpose, pumpkin peel, seeds, and fibers were evaluated. These by-products were obtained from the pumpkin varieties “Butternut squash”, “Gold nugget pumpkin”, and “Musquée de Provence” grown in Algeria. The preservative capacity of their extracts was assessed by two biological antioxidant methods, more specifically the lipid peroxidation inhibition capacity (TBRAS) and the inhibition of oxidative hemolysis (OxHLIA), and the antimicrobial assessment, tested against eight strains of bacteria, and two strains of fungi with relevance in food safety. As a first validation of safety for food application, the cytotoxicity was evaluated in a primary culture of non-tumor porcine liver cells (PLP2). Furthermore, the phenolic composition analysis was performed by HPLC-DAD-ESI/MS.The pumpkin by-products presented great preservative capacity. All samples showed microbial inhibition capacity and high antioxidant activity, especially the seeds of “Butternut squash” and “Gold nugget pumpkin”. Despite the second one did not present anti-hemolytic properties, probably due to the interference of its fat content, it presented a TBARS IC50 value lower than the control Trolox. These samples also presented better antibacterial activity than the remaining by-products, protecting against seven of the eight bacterial strains tested. All samples inhibited at least two strains of bacteria and one of two fungal strains, and none of them presented bactericidal nor fungicidal capacity, at the maximum concentration tested of 10 mg/mL. Regarding the cytotoxicity, none of the samples showed toxicity in the primary culture of non-tumor porcine liver cells (PLP2), up to the maximum concentration tested of 400 μg/mL. Interestingly, the peel of “Butternut squash” presented the most heterogeneous phenolic profile, with O-glycosylated flavonoids as the major compounds, specially isorhamnetin-O dideoxyhexosyl-hexoside ([M-H]- at m/z 769). Other type of compounds, such as citric acid ([M-H]- at m/z 191) and 4-O-(6′-O-glucosyl-4″-hydroxybenzoyl)-4-hydroxybenzyl alcohol ([M-H]- at m/z 405), have also been tentatively identified among all varieties and by-products. These results revealed pumpkin by-products as cheap and promising sources ofpreservative compounds for food application, fostering more sustainable food supply chain and promoting natural ingredients that add functional properties to the product with benefits to consumer health.
- Phenolic compounds characterization by LC-DAD- ESI/MSn and bioactive properties of Thymus algeriensis Boiss. & Reut. and Ephedra alata DecnePublication . Ziani, Borhane E.C.; Heleno, Sandrina A.; Bachari, Khaldoun; Dias, Maria Inês; Alves, Maria José; Barros, Lillian; Ferreira, Isabel C.F.R.Scientific research has been focused on finding natural occurring molecules from plant origin. Herein, infusion, decoction and hydroethanolic extracts of Thymus algeriensis Boiss. & Reut. and Ephedra alata Decne. from Algeria were phytochemically characterized by LC-DAD-ESI-MSn, and evaluated regarding bioactive properties (antioxidant and antibacterial). Flavonol and flavone glycoside derivatives and phenolic acids, specially rosmarinic acid and kaempferol-O-glucuronide were the major compounds in T. algeriensis extracts. Otherwise, E. alata presented isoflavones and flavonol derivatives as main compounds, being hydroxypuerarin isomer 1 the major molecule. Aqueous extracts had significantly higher antioxidant activity, being this activity correlated with the amount of phenolic compounds. Antimicrobial activity of the extracts was tested against multi-resistant bacteria strains from clinical isolates. The obtained MIC values indicate that the hydroethanolic extracts revealed the highest effect, especially the one of T. algeriensis against Gram-positive bacteria. Hence, these plant extracts could be used in the development of bioactive ingredients.