Production of nutritious precooked foods in developing countries by low‐cost extrusion technology

Medicinal plants represent one approach in the management of liver injuries due to various factors such as infection, toxification, and immune damage in Oriental society. One of these plants, Ganoderma (Ling Zhi, Reishi mushroom; Aphyllophoromycetideae), has been widely used for the treatment of hepatopathy of various etiologies. This article highlights the hepatoprotective activity of Ganoderma mushroom, with an emphasis on the possible biochemical mechanisms. Preclinical studies demonstrated that Ganoderma extracts, which mainly contain polysaccharides or triterpenoids, protected the liver against injury caused by exposure to toxic chemicals (e.g., CCl₄) or Bacillus Calmette-Guerin (BCG) plus lipopolysaccharide (LPS). Interestingly, Ganoderma extracts showed antihepatitis B virus (HBV) in a duckling model. A randomized placebo-controlled clinical trial by our group showed that treatment with Ganoderma polysaccharides for 12 weeks significantly decreased hepatitis B e antigen (HbeAg) and HBV DNA levels in 25% (13/52) patients with HB. The underlying mechanisms for the hepatoprotective effects of Ganoderma are largely unclear, but several potential biochemical pathways have been implicated. For example, the hepatoprotective effect of Ganoderma has been ascribed to its antioxidant and radical-scavenging activity, inhibition of β-glucuronidase, modulation of nitric oxide production, modulation of hepatic phase I and II enzymes, antifibrotic and antiviral activity, maintenance of hepatocellular calcium homeostasis, and immunomodulating effect. Given that Ganoderma has shown promising efficacy and was well tolerated for the management of various hepatic injuries, further studies are needed to explore the kinetics and mechanisms of action of Ganoderma constituents with hepatoprotective activity.     

Evaluation Antibacterial Activity of Quaternary‐Based Chitin/Chitosan Derivatives In Vitro

Abstract: Total of 3 water‐soluble quaternary‐based chitin/chitosan derivatives, which have an identical molecular weight and anion, were synthesized and characterized. Their antibacterial activities against Salmonella cholerae‐suis and Bacillus subtilis were evaluated in vitro. The polysaccharides exhibited the antibacterial efficiency. Their minimum inhibitory concentration (MIC) values vary from 0.02 to 20.48 mg/mL, and their minimum bactericidal concentration (MBC) values vary from 0.08 to 40.96 mg/mL against S. cholerae‐suis and B. subtilis, respectively. Futhermore, the extent of Bacillus subtilis cells damage was examined via transmission electron microscopy (TEM) to show how N,N,N‐trimethylchitosan (TMC) gradually destroyed and killed B. subtilis cells when they were treated with TMC. One of those quaternary polymers, O‐([2‐hydroxy‐3‐trimethylammonium])propyl chitin (OHT‐chitin), which can be directly and easily synthesized from chitin in bulk quantities, also was demonstrated its antibacterial activity. These water soluble quaternary‐based chitin/chitosan derivatives that have antibacterial effect should be potentially used as antimicrobial agents in many fields. Practical Application: The main practical application behind the investigation and evaluation antibacterial activity of 3 water‐soluble quaternary‐based chitin/chitosan derivatives could be potentially used as antimicrobial agents in many fields. These polysaccharides represent a renewable source of natural biodegradable polymers and meet with the emergence of more and more food safe problems.     

Application and bioactive properties of proteins and peptides derived from hen eggs: opportunities and challenges

Several proteins and peptides that are released in vitro and/or in vivo from hen eggs are biologically active and have a variety of functional properties in humans beyond normal nutrition, for which extensive studies have been performed. This review focuses on their biological activities, including antihypertensive, antioxidant, antimicrobial, antiadhesive, immunomodulatory and antithrombotic activities and enhancement of mineral absorption. These proteins and peptides have been shown to regulate the nervous system, cardiovascular system, immune system and gastrointestinal system. The potential application and future directions of research on these bioactive peptides and proteins in the food industry are also addressed. © 2014 Society of Chemical Industry     

Prevention of Japanese encephalitis virus infections by low-degree-polymerisation sulfated saccharides from Gracilaria sp. and Monostroma nitidum

Many researchers have utilised undigested sulfated polysaccharides as effective in vitro antiviral agents; however, their in vivo activity remains controversial. Here we report the utility of novel low-degree-polymerisation (low-DP) sulfated saccharides from two algae, Gracilaria sp. and Monostroma nitidum, in the prevention of Japanese encephalitis virus (JEV) infection both in vitro and in vivo. During in vitro studies performed by MTT or plaque assays, low-DP sulfated saccharides have slightly lower antiviral activities than their undigested polysaccharides (PS). However low-DP sulfated saccharides bind to the JEV envelope protein at least as strongly as PS. In addition, the low-DP sulfated saccharides have a distinctly higher positive effect on survivability in JEV-infected C3H/HeN mice in comparison to PS. The in vivo antiviral activity seems to be connected with better absorption of low-DP sulfated saccharides than undigested PS. Our results point out that the low-DP sulfated saccharides are promising candidates for further development as antiviral agents.     

Phytochemical compounds and biological activity in Asparagus roots: a review

Asparagus roots (AR) contain many bioactive compounds and their use in Chinese and Indian traditional medicines is well documented. Both in vitro and in vivo studies have indicated AR extracts act as antidiabetic, antioxidant and hypolipidaemic and depict anti-inflammatory, antibacterial, antiviral, anticarcinogenic activities and also improve cardiovascular and oral health. The physiological effects against wide range of pathologies are due to the wide range of phytochemicals found in AR including polyphenols, saponins and polysaccharides. The aim of this review is to present an overview of the functional, medical and physiological properties of AR bioactives. This review considers the roots of several asparagus species and provides up-to-date information on Asparagus officinalis that has not been extensively reviewed before.     

Pomegranate and its Many Functional Components as Related to Human Health: A Review

Abstract: Pomegranate (Punica granatum L.) is an ancient fruit that is widely consumed as fresh fruit and juice. The use of pomegranate fruit dates from ancient times and reports of its therapeutic qualities have echoed throughout the ages. Both in vitro and in vivo studies have demonstrated how this fruit acts as antioxidant, antidiabetic, and hypolipidemic and shows antibacterial, antiinflammatory, antiviral, and anticarcinogenic activities. The fruit also improves cardiovascular and oral health. These beneficial physiological effects may also have preventive applications in a variety of pathologies. The health benefits of pomegranate have been attributed to its wide range of phytochemicals, which are predominantly polyphenols, including primarily hydrolyzable ellagitannins, anthocyanins, and other polyphenols. The aim of this review was to present an overview of the functional, medical, and physiological properties of this fruit.     

International Regulations of Propolis Quality: Required Assays do not Necessarily Reflect their Polyphenolic‐Related In Vitro Activities

Propolis has been proposed as a polyphenolic‐rich natural product potentially able to be used for human consumption or even for medicinal proposes. To guarantee a minimum phenolic and flavonoid content and as consequence of their related‐biological activities, international requirements of propolis quality are commonly applied. In this work we assessed phenolic and flavonoid contents of propolis; the antioxidant capacity (toward peroxyl radicals and hypochlorous acid); the ability to generate nitric oxide (NO); and, finally the antimicrobial activity of 6 propolis samples from the VI region of Chile. Our results show that the total phenolic and flavonoid content of propolis samples are not always in agreement with their polyphenolic‐associated in vitro activities. For example, P03 and P06 samples showed the lowest (25 ± 4 GAE/g propolis) and the highest (105 ± 3 GAE/g propolis) total phenolic content, respectively. This was in agreement with flavonoid content and their Oxygen Radical Absorbance Capacity (ORAC) activity. However, this dependence was not observed toward HOCl, NO release and antimicrobial activity. Based on our results, we consider that, in order to guarantee the antioxidant or antimicrobial in vitro effects, the international regulations of propolis quality should contemplate the convenience of incorporating other simple analytical test such as ORAC or antimicrobial tests.     

Antimicrobial efficacies of essential oils/nanoparticles incorporated polylactide films against L. monocytogenes and S. typhimurium on contaminated cheese

Polylactide based films were formulated by incorporating polyethylene glycol, selected nanopowders (zinc oxide, silver-copper), and essential oils (cinnamon, garlic, and clove) by solvent casting method. Films were tested against three foodborne pathogens (one gram-positive and two gram-negative) for their antibacterial activity. The effectiveness of selected cinnamon oil-based film was ascertained by performing a challenge test with cheese as a food model. In vitro antibacterial efficacies of nanopowders and essential oils were also determined by the decimal reduction concentrations and the minimum bactericidal concentrations for those foodborne pathogens. It was observed that nanopowders exhibited considerably poorer decimal reduction concentrations and minimum bactericidal concentration values in comparison to the essential oils. Silver-copper alloy nanopowders exhibited lower decimal reduction concentrations and minimum bactericidal concentrations values than ZnO against tested pathogens whereas essential oils showed distinct antimicrobial effectiveness against all those pathogens with in vitro decimal reduction concentration values of 87–157 and 77–220 µg/mL for cinnamon and clove oils, respectively. Among the various formulations, it was observed that only essential oils (especially cinnamon and clove) incorporated films exhibited a significant antimicrobial activity against the selected microorganisms. These results indicate that the poor antibacterial activity of the nanopowders and the hydrophobicity of polylactide could be responsible for the ineffectiveness of nanopowders in polylactide based films. Furthermore, the challenge test indicated the polylactide/polyethylene glycol/cinnamon oil film was appropriate to inhibit the growth of L. monocytogenes and S. typhimurium on cheese up to 11 days at refrigerated storage.     

Assessment of Oligogalacturonide from Citrus Pectin as a Potential Antibacterial Agent against Foodborne Pathogens

Foodborne diseases are an important public health problem in the world. The bacterial resistance against presently used antibiotics is becoming a public health issue; hence, the discovery of new antimicrobial agents from natural sources attracts a lot of attention. Antibacterial activities of oligogalacturonide from commercial microbial pectic enzyme (CPE) treated citrus pectin, which exhibits antioxidant and antitumor activities, against 4 foodborne pathogens including Salmonella Typhimurium, Staphylococcus aureus, Listeria monocytogenes, and Pseudomonas aeruginosa was assessed. Pectin hydrolysates from CPE hydrolysis exhibited antibacterial activities. However, no antibacterial activity of pectin was observed. Citrus oligogalacturonide from 24‐h hydrolysis exhibited bactericidal effect against all selected foodborne pathogens and displayed minimal inhibitory concentration at 37.5 μg/mL for P. aeruginosa, L. monocytogenes, and S. Typhimurium, and at 150.0 μg/mL for S. aureus.     

Bacillus subtilis HJ18‐4 from Traditional Fermented Soybean Food Inhibits Bacillus cereus Growth and Toxin‐Related Genes

Bacillus subtilis HJ18‐4 isolated from buckwheat sokseongjang, a traditional Korean fermented soybean food, exhibits broad‐spectrum antimicrobial activity against foodborne pathogens, including Bacillus cereus. In this study, we investigated the antibacterial efficacy and regulation of toxin gene expression in B. cereus by B. subtilis HJ18‐4. Expression of B. cereus toxin–related genes (groEL, nheA, nheC, and entFM) was downregulated by B. subtilis HJ18‐4, which also exhibited strong antibacterial activity against B. cereus. We also found that water extracts of soy product fermented with B. subtilis HJ18‐4 significantly inhibited the growth of B. cereus and toxin expression. These results indicate that B. subtilis HJ18‐4 could be used as an antimicrobial agent to control B. cereus in the fermented soybean food industry. Our findings also provide an opportunity to develop an efficient biological control agent against B. cereus.     

Mechanical,Physical, Antioxidant,and Antimicrobial Properties of Gelatin Films Incorporated with Thymol for Potential Use as Nano Wound Dressing

The aim of this study was to determine the properties of gelatin films incorporated with thymol. Gelatin films were prepared from gelatin solutions (10% w/v) containing thymol (1, 2, 4, and 8% w/w), glycerol (25% w/w) as plasticizer, and glutaraldehyde (2% w/w) as cross‐linker. Cross‐likened films showed higher tensile strength, higher elongation at break, lower Young's modulus, lower water solubility, lower swelling, lower water uptake, and lower water vapor permeability. Incorporation of thymol caused a significant decrease in tensile strength, increase in elongation at break, decrease in Young's modulus, increase in water solubility, decrease in swelling and water uptake, and increase in water vapor permeability slightly. The films incorporated with thymol exhibited excellent antioxidant and antibacterial properties. The antibacterial activity of the films containing thymol was greatest against Staphylucoccus aureus followed by Bacillus subtilis followed by Escherichia coli and then by Pseudomonas aeruginosa. Thus, gelatin films‐containing thymol can be used as safe and effective source of natural antioxidant and antimicrobial agents with the purpose of evaluating their potential use as modern nano wound dressing. Practical Application : This study clearly demonstrates the potential of gelatin films incorporated with thymol as natural antioxidant and antimicrobial nano film. Such antimicrobial films exhibited excellent mechanical, physical, and water activities and could be used as antibacterial nano wound dressing against wounds burn pathogens.     

Effects of antimicrobial use in agricultural animals on drug-resistant foodborne salmonellosis in humans: A systematic literature review

Controversy continues concerning antimicrobial use in food animals and its relationship to drug-resistant infections in humans. We systematically reviewed published literature for evidence of a relationship between antimicrobial use in agricultural animals and drug-resistant meat or dairy-borne non-typhoidal salmonellosis in humans. Based on publications from the United States (U.S.), Canada, and Denmark from January 2010 to July 2014, 858 articles received title and abstract review, 104 met study criteria for full article review with 68 retained for which data are presented. Antibiotic exposure in both cattle and humans found an increased likelihood of Salmonella colonization, whereas in chickens, animals not exposed to antibiotics (organic) were more likely to be Salmonella positive and those that had antibiotic exposure were more likely to harbor antimicrobial resistant Salmonella organisms. In swine literature, only tylosin exposure was examined and no correlation was found among exposure, Salmonella colonization, or antimicrobial resistance. No studies that identified farm antimicrobial use also traced antimicrobial-resistant Salmonella from farm to fork.     

Short communication: Antiviral activity of subcritical water extract of Brassica juncea against influenza virus A/H1N1 in nonfat milk

Subcritical water extract (SWE) of Brassica juncea was studied for antiviral effects against influenza virus A/H1N1 and for the possibility of application as a nonfat milk supplement for use as an “antiviral food.” At maximum nontoxic concentrations, SWE had higher antiviral activity against influenza virus A/H1N1 than n-hexane, ethanol, or hot water (80°C) extracts. Addition of 0.5 mg/mL of B. juncea SWE to culture medium led to 50.35% cell viability (% antiviral activity) for Madin-Darby canine kidney cells infected with influenza virus A/H1N1. Nonfat milk supplemented with 0.28 mg/mL of B. juncea SWE showed 39.62% antiviral activity against influenza virus A/H1N1. Thus, the use of B. juncea SWE as a food supplement might aid in protection from influenza viral infection.     

Antioxidant and Antibacterial Activities on Foodborne Pathogens of Artocarpus heterophyllus Lam. (Moraceae) Leaves Extracts

Abstract: Total water extract, ethyl acetate, and aqueous fractions from the leaves of Artocarpus heterophyllus were evaluated for phenolic content, antioxidant, and antibacterial activities against some foodborne pathogens such as E. coli, Listeria monocytogenes, Salmonella typhimurium, Salmonella enterica, Bacillus cereus, Enterococcus faecalis, and Staphylococcus aureus. The minimum inhibitory concentration (MICs) of extract and fractions determined by the agar dilution method were ranged from 221.9 μg/mL for ethyl acetate fraction to 488.1 μg/mL for total extract. In the agar diffusion method the diameters of inhibition were 12.2 for the total extract, 10.7 and 11.5 for ethyl acetate and aqueous fractions, respectively. A. heterophyllus showed significant antioxidant activity tested in different in vitro systems (DPPH, ABTS, FRAP, and Fe²⁺ chelating activity assay). In particular, in DPPH assay A. heterophyllus total extract exhibited a strong antiradical activity with an IC₅₀ value of 73.5 μg/mL while aqueous fraction exerted the highest activity in FRAP assay (IC₅₀ value of 72.0 μg/mL). The total phenols content by Folin–Ciocalteau method was determined with the purpose of testing its relationship with the antioxidant and antibacterial activities. Practical Application: The appearance of food is one of the major determinants of its appeal to consumers and consequently, sales of the product. Microbial contamination and lipid oxidation are the main factors that determine food quality loss and shelf-life reduction. Therefore, preventing microbial contamination and delaying lipid oxidation are highly relevant to food processors. The growth of microorganisms in food products may cause spoilage or foodborne diseases. Oxidative processes in food products lead to the degradation of lipids and proteins which, in turn, contribute to the deterioration in flavor, texture, and color of the products. A. heterophyllus leaves extracts demonstrated interesting biological properties that suggest its use as a new potential source of natural antioxidant and antimicrobial agent.     

Chemical composition and in vitro antimicrobial activity of the essential oil of Origanum minutiflorum O Schwarz & PH Davis

The essential oil obtained by hydrodistillation from the aerial parts of Origanum minutiflorum O Schwarz & PH Davis, an endemic species in Turkey, was analysed for its antimicrobial activity in vitro. Gas chromatography/mass spectrometry analysis of the essential oil resulted in the identification of 34 constituents accounting for 961.5 mL L^?1 of the oil, the major compounds present being carvacrol (793.4 mL L^?1), p‐cymene (32.6 mL L^?1) and γ‐terpinene (21.4 mL L^?1). The in vitro antimicrobial activity of the essential oil was investigated in order to evaluate its efficacy against 16 bacteria and two yeasts, using disc diffusion and minimum inhibitory concentration methods. The essential oil showed strong antimicrobial activity against all test micro‐organisms except Pseudomonas aeruginosa. Its main components carvacrol and p‐cymene were also assayed for their antimicrobial activities. Carvacrol exhibited comparable activity to the crude oil, proving it to be the main component responsible for the biological activity observed. This study demonstrates the in vitro antimicrobial activity of the essential oil of this endemic remedy against a wide spectrum of clinically important micro‐organisms, including pathogenic yeasts, being the first report on the anticandidal properties of the essential oil of O. minutiflorum. Copyright © 2006 Society of Chemical Industry     

Bioactive constituents,in vitro radical scavenging and antibacterial activities of selected Apis mellifera honey from Kenya

There is limited information about the relative composition and health benefits of various honey consumed across Africa. This study aimed at estimating the bioactive constituents, in vitro radical scavenging and antibacterial activities of 16 kinds of honey obtained from different geographical locations in Kenya. Manuka 5 + honey was included for comparison. Some of the tested honey had biochemicals and bioactivities similar to or higher than Manuka 5 + honey. The honey exhibited DPPH radical scavenging ability, with several types of honey showing superior scavenging potential than Manuka 5 + honey, owing to their high phenol content. All types of honey inhibited the growth of E. coli and further showed a substantial amount of nonperoxide antimicrobial activity. The geographical origin of honey had an influence on its bioactive contents. Overall, these findings suggest that Kenyan honey has great therapeutic potential, and thus, its clinical application should not be overlooked.     

Probiotic and Technological Properties of Facultatively Heterofermentative Lactobacilli from Greek Traditional Cheeses

Nineteen isolates of facultatively heterofermentative lactobacilli from Feta, Graviera, and Kasseri cheeses were identified by SDS-PAGE of whole-cell proteins as L. paracasei subsp. paracasei (12 strains) and L. plantarum (7 strains) and differentiated at strain level by RAPD-PCR. Properties of technological interest, such as acidification ability, proteolytic activity, and enzyme activities, were also studied. The test strains exhibited a low acidification activity, with significant interstrain differences after growth in milk for 24 h. They were also characterized by different casein breakdown ability, with around 50% of them accumulating amino acids at low amounts in the milk. Lactobacilli isolates differed in respect of enzyme activities, with β-galactosidase being the strongest activity found. Their probiotic potential was evaluated with in vitro studies on the resistance to low pH, bile salts, and pancreatin. The isolates from Feta showed a better survival than those from Kasseri and Graviera at low pH and viable cells were detected even after 3 h at pH 2.0. All strains tolerated bile salts at 0.3% and retained viability in the presence of pancreatin at 0.1%. Different patterns of antibacterial activities were recorded. The strains inhibited preferentially LAB species and some of them clostridia, E. coli O44 and B. cereus. Distinguished strains are promising probiotic candidates as adjuncts and deserve further studies.     

Investigating the Antimicrobial Efficacy of a Lactococcal Bacteriocin for the Development of Microbiologically Stable Beer

Barley isolate Lactococcus lactis M30 produces an antimicrobial proteinaceous activity, which at least under laboratory conditions was shown to target beer spoiling lactic acid bacteria, including Lactobacillus brevis BSH9. The aim of this study was to investigate the application of this antibacterial activity at various stages of the brewing process and in packaged beer. Lactococcus lactis M30 was shown to produce the antimicrobial activity during growth under specific conditions in fortified unhopped wort. However, this activity was lost during wort boiling and yeast fermentation. When the bacteriocin was added directly to beer it retained in vitro activity following pasteurisation, while it was also shown to inhibit growth in situ when pasteurised beer was challenged with low levels of the beer spoiling Lactobacillus brevis BSH9 culture. The capacity of the bacteriocin to prevent microbial spoilage of beer was tested at various temperatures over a period of seven weeks. Storage of bacteriocin‐containing beer at 30°C or room temperature resulted in a decrease in antimicrobial activity over time, but when refrigerated or frozen, this beer retained sufficient activity to be effective against Lactobacillus brevis BSH9.     

Characterization of an i-type lysozyme gene from the sea cucumber Stichopus japonicus, and enzymatic and nonenzymatic antimicrobial activities of its recombinant protein

Because sea cucumbers lack a well-developed immune system and can ingest pathogenic bacteria together with food, some form of active antibacterial substances must be present in the body for defense. In this study, the cDNA of an i-type lysozyme from the sea cucumber Stichopus japonicus (designated SjLys) was cloned by RT-PCR and RACE PCR techniques. The full length cDNA of SjLys was 713 bp with an open reading frame of 438 bp coding for 145 amino acids. Two catalytic residues (Glu34 and Asp47), conserved in i-type lysozymes, and a highly conserved region near the active site, MDVGSLSCG(P Y)(Y F)QIK, were detected in SjLys. In addition, the domain structure analysis of SjLys showed that it is highly similar to the medicinal leech destabilase, which belongs to a new phylogenetic family of invertebrate lysozymes possessing both glycosidase and isopeptidase activities. To gain insight into the in vitro antimicrobial activities of SjLys, the mature peptide coding region was heterologously expressed in Escherichia coli. The recombinant SjLys protein displayed an inhibitive effect on the growth of the tested Gram-positive and Gram-negative bacteria. A remarkable finding is that the recombinant SjLys exhibited more potent activities against all tested bacterial strains after heat-treating at 100 °C for 50 min. These results indicated that the S. japonicus lysozyme is an enzyme with combined enzymatic (glycosidase) and nonenzymatic antibacterial action.