Bioactive fungal polysaccharides as potential functional ingredients in food and nutraceuticals

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The seaweed holobiont: from microecology to biotechnological applications

In the ocean, seaweed and microorganisms have coexisted since the earliest stages of evolution and formed an inextricable relationship. Recently, seaweed has attracted extensive attention worldwide for ecological and industrial purposes, but the function of its closely related microbes is often ignored. Microbes play an indispensable role in different stages of seaweed growth, development and maturity. A very diverse group of seaweed-associated microbes have important functions and are dynamically reconstructed as the marine environment fluctuates, forming an inseparable ‘holobiont’ with their host. To further understand the function and significance of holobionts, this review first reports on recent advances in revealing seaweed-associated microbe spatial and temporal distribution. Then, this review discusses the microbe and seaweed interactions and their ecological significance, and summarizes the current applications of the seaweed–microbe relationship in various environmental and biological technologies. Sustainable industries based on seaweed holobionts could become an integral part of the future bioeconomy because they can provide more resource-efficient food, high-value chemicals and medical materials. Moreover, holobionts may provide a new approach to marine environment restoration.     

Bioactive compounds from cyanobacteria and microalgae: an overview

Cyanobacteria (blue-green algae) are photosynthetic prokaryotes used as food by humans. They have also been recognized as an excellent source of vitamins and proteins and as such are found in health food stores throughout the world. They are also reported to be a source of fine chemicals, renewable fuel and bioactive compounds. This potential is being realized as data from research in the areas of the physiology and chemistry of these organisms are gathered and the knowledge of cyanobacterial genetics and genetic engineering increased. Their role as antiviral, anti-tumour, antibacterial, anti-HIV and a food additive have been well established. The production of cyanobacteria in artificial and natural environments has been fully exploited. In this review the use of cyanobacteria and microalgae, production processes and biosynthesis of pigments, colorants and certain bioactive compounds are discussed in detail. The genetic manipulation of cyanobacteria and microalgae to improve their quality are also described at length.     

The food and drug legislation of 1906

Pray for the welfare of government; since were it not for the fear of government; men would swallow each other alive.     

Bioactive food components and cancer risk reduction

Research over the last three decades has provided convincing evidence to support the premise that diets rich in fruits and vegetables may be protective against the risk of different types of cancers. Initial evidence for protective effect of fruits and vegetables against cancer risk came from population-based case-control studies, which prompted intense research aimed at (a) identification of bioactive component(s) responsible for the anticancer effects of fruits and vegetables, (b) elucidation of the mechanisms by which bioactive food components may prevent cancer, and (c) determination of their efficacy for prevention of cancer in animal models. The bioactive components responsible for cancer chemopreventive effects of various edible plants have now been identified. For instance, anticancer effect of Allium vegetables including garlic is attributed to organosulfur compounds (e.g., diallyl trisulfide). Interestingly, unlike cancer chemotherapy drugs, many bioactive food components selectively target cancer cells. Molecular basis for selectivity of anticancer bioactive food components towards cancer cells remains elusive, but these agents appear promiscuous and target multiple signal transduction pathways to inhibit cancer cell growth in vitro and in vivo. Despite convincing observational and experimental evidence, however, limited effort has been directed towards clinical investigations to determine efficacy of bioactive food components for prevention of human cancers. This article reviews current knowledge on cancer chemopreventive effects of a few highly promising dietary constituents, including garlic-derived organosulfides, berry compounds, and cruciferous vegetable-derived isothiocyanates, and serves to illustrate complexity of the signal transduction mechanisms in cancer chemoprevention by these promising bioactive food components.     

Bioactive volatile compounds from marine algae: feeding attractants

Chemical communications play an important role in plants, fungi, and algae. Volatile organic compounds in marine algae are released into the seawater. These compounds play a role as either pheromones or allelochemicals. We observed that the turbinid gastropod Lunella coronata coreensis inhabits the intertidal zone and often grazes the green alga Ulva pertusa. Feeding tests and feeding preference studies were performed with green, brown and red algae or by using the powdered freeze-dried seaweed in agar. The snails fed on U. pertusa preferentially compared to the other marine algae, and recognized chemoreception compounds from the alga but not their structural or morphological differences. From feeding tests using artificial foods, it is suggested that the feeding attractants are in the essential oil of the alga U. pertusa.     

Bioactive polar natural compounds from garlic and onions

Bioactive natural compounds from garlic and onions have been the focus of researches for decades, firstly due to their pharmacological effects, and secondly due to their defence properties against plant diseases. In fact, garlic and onion, belonging to Allium genus, are among the oldest food plants known since ancient times and used as ingredient of many recipes and for therapeutic properties. These plants are well known to produce bioactive apolar sulphur compounds but less is known about their polar natural compounds, such as phenols, sapogenins and saponins, that are more stable to cooking, So, we continued our work on the discovery of polar bioactive metabolites from Allium with the isolation of a number of sapogenins and saponins from the wild onion species Allium elburzense, Allium hirtifolium, Allium atroviolaceum, and Allium minutiflorum, and, more recently, from the cultivated white onion, Allium cepa, and garlic, Allium sativum. In particular, the sapogenins and saponins isolated from A. elburzense and A. hirtifolium, named elburzensosides and hirtifoliosides respectively, exhibited significant antispasmodic properties. In addition, the saponins named minutosides isolated from A. minutiflorum showed promising antimicrobial activity. More recently the phytochemical analysis of A. cepa and A. sativum has been undertaken and afforded the characterization of saponins, phenols and N-cynnamic amides which showed significant antifungal activity.     

The brown seaweed genus Zonaria: major features,biotechnological potential,and applications

Journal of Applied Phycology - This review is a broad overview of species of the genus Zonaria, a relevant taxonomic grouping within the brown algae, considering data regarding the most common...     

Bioactive triterpenoid saponins and phenolic compounds against glioma cells

A total of 54 natural origin compounds were evaluated for their activity in inhibiting the proliferation of glioma cells. Results showed that four Aesculus polyhydroxylated triterpenoid saponins (3–6), six Gleditsia triterpenoid saponins (7–12), and five phenolic compounds (43–46, 51) had dose-dependent activity suppressing the proliferation of both C6 and U251 cells. Structure–activity relationship analysis suggested that the acetyl group at C-28 for the Aesculus saponins and the monoterpenic acid moiety for the Gleditsia saponins could be critical for the activity of these active compounds. Aesculioside H (4), gleditsioside A (7), and feuric acid 3,4-dihydroxyphenethyl ester (FADPE, 46) were the three most active compounds from the different types of the active compounds and induced apoptosis and necrosis in glioma cells.     

Bioactive compounds in legumes: pronutritive and antinutritive actions. Implications for nutrition and health

Legume seeds are employed as a protein source for animal and human nutrition not only for their nutritional value (high in protein, lipids and dietary fibre), but also their adaptability to marginal soils and climates. Human consumption of legumes has been increased in recent years, being regarded as beneficial food ingredients. Legume seeds contain a great number of compounds which qualify as bioactive compounds with significant potentials benefits to human health. These compounds vary considerably in their biochemistry and they can be proteins, glycosides, tannins, saponins, alkaloids, etc. Hence, methods for their extraction, determination and quantification are specific of each compound. They do not appear equally distributed in all legumes, and their physiological effects are diverse. Some of these compounds are important in plant defence mechanisms against predators or environmental conditions. Others are reserve compounds, accumulated in seeds as energy stores in readiness for germination. Processing generally improves the nutrient profile of legume seed by increasing in vitro digestibility of proteins and carbohydrates and at the same time there are reductions in some antinutritional compounds. Most antinutritional factors are heat-labile, such as protease inhibitors and lectins, so thermal treatment would remove any potential negative effects from consumption. On the other hand tannins, saponins and phytic acid are heat stable but can be reduced by dehulling, soaking, germination and/or fermentation. New directions in bioactive compounds research in the last decade have led to major developments in our understanding of their role in nutrition. The scientific interest in these compounds is now also turning to studies of their possible useful and beneficial applications as gut, metabolic and hormonal regulators and as probiotic/prebiotic agents.     

Bioactive phenolic compounds: production and extraction by solid-state fermentation. A review

Interest in the development of bioprocesses for the production or extraction of bioactive compounds from natural sources has increased in recent years due to the potential applications of these compounds in food, chemical, and pharmaceutical industries. In this context, solid-state fermentation (SSF) has received great attention because this bioprocess has potential to successfully convert inexpensive agro-industrial residues, as well as plants, in a great variety of valuable compounds, including bioactive phenolic compounds. The aim of this review, after presenting general aspects about bioactive compounds and SSF systems, is to focus on the production and extraction of bioactive phenolic compounds from natural sources by SSF. The characteristics of SSF systems and variables that affect the product formation by this process, as well as the variety of substrates and microorganisms that can be used in SSF for the production of bioactive phenolic compounds are reviewed and discussed.     

Bacteriophage endolysins: applications for food safety

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Nanoliposomes and their applications in food nanotechnology

Food nanotechnology involves the utilization of nanocarrier systems to stabilize the bioactive materials against a range of environmental and chemical changes as well as to improve their bioavailability. Nanoliposome technology presents exciting opportunities for food technologists in areas such as encapsulation and controlled release of food materials, as well as the enhanced bioavailability, stability, and shelf-life of sensitive ingredients. Liposomes and nanoliposomes have been used in the food industry to deliver flavors and nutrients and, more recently, have been investigated for their abilityto incorporate antimicrobials that could aid in the protection of food products against microbial contamination. In this paper, the main physicochemical properties of liposomes and nanoliposomes are described and some of the industrially applicable methods for their manufacture are reviewed. A summary of the application of nanoliposomes as carrier vehicles of nutrients, nutraceuticals, enzymes, food additives, and food antimicrobials is also presented.     

Taste-active compounds in a traditional Italian food: 'lampascioni'

Nature is a rich source of taste-active compounds, in particular of plant origin, many of which have unusual tastes. Many of these are found in traditional food, where spontaneous plants are used as ingredients. Some taste-active compounds were identified in the bulbs of Muscari comosum, a spontaneous plant belonging to the family of the Liliaceae, very common in the Mediterranean area, and used in traditional gastronomy (called 'lampascioni' in South Italy). The bulbs were extracted with a series of solvents of different polarity. The different fractions were submitted to a preliminary sensory evaluation, and the most interesting ones, characterized by a strong bitter taste and some chemestetic properties, were submitted to further purification and structural analysis. From the ethereal extract, several 3-benzyl-4-chromanones and one stilbene derivative were isolated. Pure compounds were examined for their taste activity by means of sensory evaluation, and proved to be responsible for the characteristic taste of this food. Some of these compounds have been synthesized de novo to confirm their structure.