Current Nutrition & Food Science (v.13, #2)

Meet Our Editorial Board Member by Joseph R. Prohaska (77-77).

During the last century, notable attention has been sporadically directed on health benefits derived from consumption of milk products such as acidophilus milk. The tangy flavor and thickened texture of acidophilus milk can be correlated to added Lactobacillus acidophilus bacteria. Aflatoxin M1 (AFM1) is the result of secondary metabolites of different fungal strains. Because of the important role of dairy products in human life, especially children, a huge concern raised regarding the presence of AFM1 in consumed products. Due to serious threats to both human health and economics in all societies, the control of AFM1 is crucial. However, several physical or chemical detoxification methods were developed to removing or inactivating of AFM1, nowadays customers prefer to consume the products with lowest changes in composition as well as highest level of nutrient value. In this context, biological methods can be considered as one of the possible alternatives for conventional detoxification methods. Recently, the application of Lactic Acid Bacteria (LAB) for the reduction of AFM1 by approaching of produced metabolites and binding of AFM1 with LAB was introduced. The major aim of this present review is to highlight the feasibility of using LAB (Streptococcus thermophilus, Streptococcus bulgaricus Lactobacillus bulgaricus, Lactobacillus helviticus, Lactobacillus plantarum, Lactococcus spp.) in order remove the AFM1 from one kind of dairy base beverages (Acidophilus milk).

Background: The trace element selenium (Se) is essential nutrition mineral. Selenium deficiencies in the human and animal organism are recognized worldwide to be related to a number of pathologies. However, at higher Se concentrations, harmful consequences occur: generation of free radicals, DNA double-strand breaks, and apoptosis in cells. Provided that the recommended dietary intakes are not met, Se-rich foods are to be included in the diet.

Limitation of Se Studies: The disparate opinions on the widely discussed chemopreventive capability of selenium have to be addressed. Of paramount importance is a better understanding of the Se significance to the DNA preservation and cancer. The contradictions found might be related to poor understanding of controversial mechanisms involved in selenium biochemistry. Therefore, a rich area of selenium explorations could be considered as two fields: Se as a dietary component and Se as a toxic agent.

Selenized Fungi: Mushrooms and yeasts have attracted a number of researchers in food and pharmaceuticals. Mushroom-based foods enriched with selenocompounds could be a convenient source of Se to balance the deficiency. Therewith the safety and efficacy factors favor the organic forms of Se.

Conclusion: The consequences of selenium toxicity, bioavailability of selenium content, the importance and possibilities for increasing selenium content of mushroom mycelia, a fate of organoselenium xenobiotics in the basidiomycetes culture are discussed in this review.

Chemical Composition, Antioxidant and Antimicrobial Activities of the Essential Oils of Three Algerian Lamiaceae Species by Khadidja Houda Benabed, Nadhir Gourine, Mohamed Ouinten, Isabelle Bombarda, Mohamed Yousfi (97-109).
Background: The present work investigates the chemical composition, the antioxidant and the antimicrobial activities of the Essential Oils (EOs) of three species of the Lamiaceae family gowning in Algeria: Thymus vulgaris L., Thymus algeriensis Boiss. & Reut. and Mentha pulegium L.

Methods: Essential Oils (EOs) obtained by hydrodistillation of the aerial parts of the studied plants were analyzed by GC and GC-MS. The antioxidant activity of the EOs was determined using two different assays: free radical scavenging activity of DPPH. (2,2-diphenyl-1-picrylhydrazyl) and Phosphomolybdenum reducing power. The EOs were also tested for their antibacterial and antifungal activities against eight pathogenic bacteria (Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli, Bacillus cereus, Staphylococcus aureus, Methicillin resistant strain of S. aureus “MRSA” and Enterococcus faecalis); a yeast (Candida albicans); and a fungi (Fusarium oxysporum).

Results: For DPPH assay, T. vulgaris presented very interesting activity. At the opposite, T. algeriensis (Aflou) and M. pulegium, were the most active EOs in term of Phosphomolybdenum assay. The antimicrobial activity of T. vulgaris was found to be the most active EO and exhibited important resistance against most of studied bacteria. For disc diffusion test, the most active EO plant was T. algeriensis. Alternatively, and for antifungal activity, T. vulgaris presented the highest value of MFC.

Conclusion: The antioxidant activity test's results showed that the EOs exhibited important reducing powers but weak scavenging activities. On the other hand, it was found that some EO samples have shown very interesting antimicrobial activities. Actually, among the investigated EOs, T. vulgaris presented the strongest antibacterial and antifungal activities.

Background: Traditional fermented foods are a typical niche for probiotic Lactic Acid Bacteria (LAB) and are involved with many therapeutic attributes. Among LAB, Lactobacillus plantarum is one of the most versatile members. Several L. plantarum strains have been documented for their probiotic attributes. There are limited reports on the evaluation of probiotic potential along with the therapeutic properties such as antioxidative ability. With this background, the present study was carried out to screen 'Sannas' which is collected from the Coorg region of Karnataka state, India, in the presence of potential probiotic L. plantarum strains for their therapeutic potential.

Methods: Sannas was screened for the potential probiotic strains and identified using physiological, biochemical and molecular methods. A series of probiotic attributes were assessed for the selection of potential probiotic strains. Further, the potential probiotic strains were assessed for the in vitro antibiofilm activity against Pseudomonas aeruginosa MTCC 7903. In addition, the cholesterol lowering ability of the potential probiotic strain using four-percent commercial fresh hen egg yolk as the cholesterol source. On the other hand, the in vitro antioxidant activity was also determined by a series of assays. Furthermore, the toxicity assessment was also done by the mitotic index using onion root tips as the source of chromosomes.

Results: L. plantarum MYS14 isolated from an unexploited traditional cereal-based fermented food had good functional probiotic attributes and the antibiotic susceptibility was an intrinsic feature, thus consumption of this strain does not possess any health risk to humans and animals. In addition, the strain exhibited strong radical scavenging activity which might be useful in controlling or slowing the progress of several oxidative stress related disorders. On the other hand, the strain also exhibited better cholesterol assimilation, antibiofilm ability and the mitotic index revealed the non-toxic effect of the CFS.

Conclusion: The probiotic therapy is gaining significant research interest in relation to gut microbiota in an attempt to better understand the therapeutic potential of probiotic strains isolated from unexploited traditional cereal based foods. It is confirmed that this L. plantarum MYS14 strain possesses several characteristics suitable for the production of various antioxidant probiotic products. Collectively, the results suggest that L. plantarum MYS14 may be used as probiotic strain for therapeutic applications.

Lipid Classes, Fatty Acids, Tocopherols Compositions and Antioxidant Activity of Lawsonia alba Seed Oils Growing in Algeria by Rekia Cherbi, Chahrazed Hamia, Nadhir Gourine, Isabelle Bombarda, Mokhtar Saidi, Mohamed Yousfi (121-130).
Background: Lawsonia alba seed oils are not widely used commercially even though they have characteristics that well suit for industrial applications and can contribute to healthy human diets. The most important aim of the present work is the evaluation of the tocopherols composition of these oils. Moreover, lipid classes, fatty acids compositions and antioxidant activity of the seed oils were also investigated.

Methods: Lawsonia alba seed oils were extracted with Soxhlet device using n-hexane and chloroform/methanol. Tocopherols were analyzed by HPLC, and then their antioxidant activities were determined using two different assays: DPPH (1,1-diphenyl-2-picrylhydrazyl), and Phosphomolybdenum.

Results: The content of the oils ranged from 7.52 to 10.45%. Polyunsaturated fatty acids dominated all the studied samples. Linoleic, followed by palmitic and oleic, were the major fatty acids found in the crude seed oils and their lipid classes. Results of tocopherols identification showed that the seed oils were rich in tocopherols, especially γ- and δ- tocopherols. For DPPH assay, the antioxidant powers varied from medium to low values (IC50 = 0.11 to >31.96 mg/mL). The results of the Phosphomolybdenum assay showed very important activities of the oils that were decreasing in the following order: polar lipids > neutral lipids (Chloroform/Methanol) > total lipids > neutral lipids (n-hexane).

Conclusion: this current report reveals the richness of the Lawsonia alba seeds in tocopherols, which in fact is studied for the first time. Moreover, cluster analysis revealed that fatty acid composition of the seed oils of Lawsonia alba were very close to those of Walnut.

A Study on the Composition and Antioxidant Properties of Avicennia marina Leaf Extract by Mohammad Molaee, Mohammad Ali Sahari, Reza Esmaeilzadeh Kenari, Shiva Amirkaveei, Elahe Arbidar (131-136).
Background: Today, the use of antioxidants, especially natural antioxidants, to prevent oxidation is preferred because it has neither the harmful effects of synthetic antioxidants nor requires complex process. In this study, the bioactive compounds and antioxidant properties of mangrove (Avicenna marinia) ethanolic extract were evaluated.

Methods: The antioxidant activity of the extract was investigated by DPPH?, β-carotene bleaching and ferric reducing power tests. The total phenolic content of the Avicenna marinia extract was obtained by Folin-Ciocalteau colorimetric method. Data analysis was performed using SAS, and comparison of average data was done using Least Significant Difference (LSD) at a level of 0.01.

Results: The results showed that total phenolic content of the extract was 18.721± 0.14 mg of gallic acid per gram of extract, and in the DPPH radical test, EC50 index was 9650 ± 342 ppm. The major compounds of leaf extract of Avicennia marina were cryptomeridiol (7.82%) and cedrondiol (7.13%).

Conclusion: Avicenna marinia leaf extract as natural antioxidants can replace synthetic antioxidants.

Study about How A Sample of Portuguese People Perceive the Health Benefits of Dietary Fibre by Raquel P.F. Guine, Manuela Ferreira, Paula Correia, Joao Duarte (137-146).
Background: Dietary Fibre (DF) has been part of human diet since ever, and its benefits for the human health have been well established and scientifically confirmed. However, it is important to study to what extent people are aware of those benefits.

Objective: Having in mind the importance of DF the present work was undertaken to study the level of knowledge of people residing in Portugal about the health effects related to DF.

Methods: A descriptive cross-sectional study was undertaken on a non-probabilistic sample of 382 adult participants. Descriptive statistics were used together with some inferential tests, all using the software SPSS and considering a level of significance of 5%.

Results: The results allowed concluding that people were differently informed about the effects of DF in preventing and/or treating various diseases, being constipation the most recognized, followed in decreasing order by obesity, bowel cancer, cholesterol, cardiovascular diseases, diabetes and breast cancer. The results also showed that significant differences were encountered between age groups for most of the diseases evaluated, but not between genders, levels of education or living environments.

Conclusion: Generally, it was concluded that the participants in this study were relatively well informed about the roles of DF in preventing and/or treating several diseases.

Characterization of the Cultivable Gut Microflora in Wild-Caught Mediterranean Fish Species by Ahmad Jammal, Michel Bariche, Heinrich zu Dohna, Zakaria Kambris (147-154).
Background: Microflora of the gastrointestinal tract plays important roles in food digestion, nutrient absorption and in host defense against ingested pathogens. Several studies have focused on the microflora of farmed fishes, but the gut flora of wild fishes remains poorly characterized. The aim of this work was to provide an overview of the bacteria colonizing the gut of wild-caught fishes and to determine whether some bacterial species can be pathogenic.

Results: We isolated cultivable bacteria from fifteen wild-caught Mediterranean fish species corresponding to different habitat, diet and origin. Bacterial species identity was determined by 16s rRNA gene sequencing for the 61 isolates. The potential pathogenicity of isolated bacteria was investigated using fruit fly (Drosophila melanogaster) and zebrafish (Danio rerio) as model organisms. Two bacterial strains (Serratia sp. and Aeromonas salmonicida) were lethal when microinjected to Drosophila, while zebrafish did not develop any disease when exposed to any of 34 isolated bacterial strains. However, it was interesting to note that two bacterial strains (Shewanella and Arthrobacter) isolated from marine fishes were able to colonize the guts of freshwater zebrafish.

Conclusion: The results of this study give an overview of the bacterial species found in the guts of wild fishes living off Beirut seashore. It shows that some parameters believed to be limiting factors to host-gut colonization by bacteria can be overcome by some species. This pilot study could be extended by sampling a larger number of fish species with several specimens per fish species, and by identifying uncultivable bacteria that reside in the fish guts. Our results may have implications for the utilization of certain bacterial species in fish farming or their use as bio-indicators for water and/or food quality.