Long-term maintenance of the sea urchin Paracentrotus lividus in culture

Abstract The common sea urchin Paracentrotus lividus (Lamarck, 1816) is an important commercial species in the Mediterranean Sea for the consumption of its gonads (roe). This species has also long been used as an animal model in developmental biology and as an indicator in the assessment of environmental quality. In recent decades, the exploitation of this marine resource has become increasingly intensive, causing the depletion of wild stocks. The ripple effect observed in the laboratory use of this species has been the growing difficulty in finding valiant mature animals in the wild. We focused on the long-term maintenance of wild P. lividus and on the essential question of diet to maintain the animals and improve gonad development. The use of practical ration blocks which are nutrient-rich and show stability, easy storage and handling, resulted reduction in labor requirement and time for feeding streamlining the feeding practice. A significantly higher gonad production and a prolonged period of reproduction were obtained compared to wild caught individuals over the same period of time

Iron (II) citrate complex as a food supplement: Synthesis, characterization and complex stability

Iron deficiency represents a widespread problem for a large part of the population, especially for women, and has received increasing attention in food/supplement research. The contraindications of the iron supplements commercially available (e.g., imbalances in the levels of other essential nutrients, low bioavailability, etc.) led us to search for a possible alternative. In the present work, a rapid and easy method to synthetize a solid iron (II) citrate complex from iron filings and citric acid was developed to serve, eventually, as a food supplement or additive. In order to state its atomic composition and purity, an assortment of analytical techniques was employed (e.g., combustion analysis, thermogravimetry, X-ray diffractometry, UV/Vis spectrophotometry, etc.). Results demonstrate that the synthesized crystalline solid corresponds to the formula FeC6H6O7∙H2O and, by consequence, contains exclusively iron (II), which is an advantage with respect to existing commercial products, because iron (II) is better absorbed than iron (III) (high bioavailability of iron)

Allium ursinum and Allium oschaninii against Klebsiella pneumoniae and Candida albicans Mono- and Polymicrobic Biofilms in In Vitro Static and Dynamic Models

The present study assesses the in vitro antibiofilm potential activity of extracts of wild Allium ursinum and Allium oschaninii. The active ingredients of the extracts were obtained with a technique named Naviglio (rapid solid–liquid dynamic extraction, RSLDE) which is based on an innovative and green solid–liquid extraction methodology. The extracts were tested against models of mono‐ and polymicrobial biofilm structures of clinically antibiotic‐resistant pathogens, Klebsiella pneumoniae ATCC 10031 and Candida albicans ATCC 90028. Biofilms were studied using a static and a dynamic model (microtiter plates and a CDC reactor) on three different surfaces reproducing what happens on implantable medical devices. Antimicrobic activities were determined through minimum inhibitory concentration (MIC), while antibiofilm activity was assessed by minimum biofilm eradication concentration (MBEC) using a crystal violet (CV) biofilm assay and colony forming unit (CFU) counts. Results showed that both Allium extracts eradicated biofilms of the tested microorganisms well; biofilms on Teflon were more susceptible to extracts than those on polypropylene and polycarbonate, suggesting that when grown on a complex substrate, biofilms may be more tolerant to antibiotics. Our data provide significant advances on antibiotic susceptibility testing of biofilms grown on biologically relevant materials for future in vitro and in vivo applications

Antioxidant Properties of Pulp, Peel and Seeds of Phlegrean Mandarin (Citrus reticulata Blanco) at Different Stages of Fruit Ripening

In this work, we assess the potential of waste products of Phlegrean mandarin (Citrus reticulata Blanco), namely seeds and peel, to be reutilized as a source of bioactive compounds beneficial for the human diet. Starting from the evidence that the by-products of this specific cultivar are the most powerful sources of antioxidants compared to pulp, we have investigated if and how the bioactive compounds in peel and seeds may be affected by fruit ripening. Three stages of fruit ripening have been considered in our study: unripe fruits = UF, semi-ripe fruits = SRF, ripe fruits = RF. The overall results indicated that RF showed the highest concentration of antioxidants. Among fruit components, peel was the richest in total antioxidant capacity, total polyphenol content, total flavonoids, total chlorophylls and carotenoids, while seeds exhibited the highest concentration of total condensed tannins and ascorbic acid. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay indicates the occurrence, in peel extracts, of 28 phenolic compounds, mainly flavonoids (FLs); in seeds, 34 derivatives were present in the first stage (UF), which diminish to 24 during the ripening process. Our data indicated that the content of phytochemicals in citrus strongly varies among the fruit components and depends on the ripening stage. The higher antioxidant activity of peel and seeds, especially in RF, encourage a potential use of by-products of this specific citrus cultivar for industrial or pharmacological applications. However, to maximize the occurrence of desired bioactive compounds, it is important also to consider the ripening stage at which fruits must be collected

Rapid solid-liquid dynamic extraction (RSLDE): a powerful and greener alternative to the latest solid-liquid extraction techniques

Traditionally, solid-liquid extractions are performed using organic and/or inorganic liquids and their mixtures as extractant solvents in contact with an insoluble solid matrix (e.g., the Soxhlet method) or using sequential atmospheric pressure systems that require long procedures, such as maceration or percolation. The objective of this procedure is the extraction of any compounds that can be carried out from the inner solid material to the outlet, resulting in a solution containing colorants, bioactive compounds, odorous substances, etc. Over the years, in the extraction techniques sector, there have been many important changes from the points of view of production, quality, and human and environmental safety due to improvements in technology. In more recent times, the interest of the scientific community has been aimed at the study of sustainable processes for the valorization of extracts from vegetables and food by-products, through the use of non-conventional (innovative) technologies that represent a valid alternative to conventional methods, generally through saving time and energy and the formation of fewer by-products. Therefore, with the development of principles based on the prevention of pollution, on a lower risk for human health, and on a low environmental impact, new systems have been implemented to reduce extraction times and solvent consumption, to improve efficiency, and to increase the productivity of the extracts. From this point of view, rapid solid-liquid dynamic extraction (RSLDE), performed using the Naviglio extractor, compared to traditional applications, is a technique that is able to reduce extraction times, generally leads to higher yields, does not require heating of the system, allows one to extract the active ingredients, and avoids their degradation. This technique is based on a new solid-liquid extraction principle named Naviglio’s principle. In this review, after reviewing the latest extraction techniques, an overview of RSLDE applications in various research and production sectors over the past two decades is provided

Study of the Kinetics of Extraction Process for The Production of Hemp Inflorescences Extracts by Means of Conventional Maceration (CM) and Rapid Solid-Liquid Dynamic Extraction (RSLDE)

In the present work, the kinetics of the extraction process from female inflorescences of Canapa sativa subsp. sativa var. sativa were studied, on the basis of determination of the content of cannabinoids: cannabidiolic acid (CBDA), D9-tetrahydrocannabinolic acid (THCA), cannabidiol (CBD) and D9-tetrahydrocannabinol (THC), before and after decarboxylation in the oven, in order to evaluate the possible use of the hemp extract obtained in the food sector. Therefore, both conventional maceration (CM) and rapid solid-liquid dynamic extraction (RSLDE), also known as cyclically pressurized extraction (CPE), were carried out, using parts of the plant approximately of the same size. The alcoholic extracts thus obtained were analyzed by high-performance liquid chromatography (HPLC) in order to calculate the percentages of cannabinoids present in the inflorescences and thus be able to evaluate the degree of decarboxylation. Furthermore, the extracts were dried to calculate the percentage of solid material present in it, that was made mainly by cannabinoids. The amount of substance extracted from the inflorescences was about 10% (w/w), for both cases considered. Therefore, the extraction yield was the same in the two cases examined and the final qualities were almost identical. However, the extraction times were significantly dierent. In fact, the maceration of hemp inflorescences in ethyl alcohol was completed in no less than 24 h, while with the RSLDE the extraction was completed in only 4 h. Finally, for a better understanding of the extraction process with cyclically pressurized extraction, a numerical simulation was carried out which allowed to better evaluate the influence of extractive parameters

A water extraction process for lycopene from tomato waste using a pressurized method: an application of a numerical simulation

Lycopene is a red carotenoid pigment found in fresh tomatoes. Several epidemiological studies show that the lycopene content of tomatoes and tomato-based products is related to a variety of health benefits due to its antioxidant activity, which is fundamental in treating cardiovascular diseases, slowing down cellular ageing and preventing some forms of cancer. Furthermore, several studies in the past few years have shown that by-products of tomato processing contain significant amounts of bioactive phytochemicals, including lycopene, that once extracted from the tomato skin could be used as natural antioxidants for the formulation of functional foods or as additives in food systems to extend their shelf life. The purpose of this study was to evaluate the extractive process of lycopene, starting from tomato skin waste, performing a cyclically pressurized extraction process or rapid solid–liquid dynamic extraction, using a Naviglio Extractor. This is an alternative approach to recent solid–liquid extractive processes that depends on diffusion and the pressure/de-pressure mechanism, which was considered to account for the driving force (convective effect) of the accelerated extraction of compounds contained in vegetables (or, more generally, solid matrices) and those not chemically bonded to the chemical structure of solids that are insoluble in the liquid extractant. The chromatographic analysis by high-performance liquid chromatography of the lycopene extract obtained showed a purity of more than 98% (w/w). Finally, a numerical simulation of the process was performed, obtaining useful information about the kinetics of the process (time history) as well as its mathematical description. The numerical simulation supports the validity of Naviglio’s principle

Various Applications of Processing of Olive Leaves Waste Extracted with RSLDE: A Green Technology

There is no waste in nature. Everything that is produced has a purpose and everything that becomes waste can be transformed into a new resource, triggering a virtuous circuit that feeds itself. The circular economy of waste means a system in which the production-consumption-disposal process is overcome to replace it with a circular model, where the final waste product is re-introduced into the circulation as a secondary raw material. The logic to follow is that after consumption and before any disposal, it is necessary to activate virtuous processes such as reduce, reuse, and recycling. This work focuses on the possible uses of a vegetable waste matrix, such as olive leaves. The olive tree (Olea europaea) is a fruit tree, cultivated for more than 3500 years for its fruits and edible oil. However, just like oil, olive leaf contains a high amount of polyphenols, in particular oleuropein, one of the most powerful natural antioxidants known and hydroxytyrosol, which also has powerful antiseptic properties. Therefore, olive leaf extracts, thanks to the presence of oleuropein associated with hydroxytyrosol, represent a powerful natural antioxidant, a valid ally of the cardiovascular system. In addition, olive leaves are an excellent regulator of the digestive system: they regulate intestinal transit and above all eliminate fungi and other unwanted parasites from the body. Starting from these premises, in this work, a green extraction technique such as rapid solid liquid dynamic extraction (RSLDE) is compared with conventional maceration to obtain an olive leaf extract rich in antioxidants to be used in various sectors

Extraction and Purification of Phycocyanin from Arthrophira platensis Microalgae Using a Green Solid-Liquid Extraction Technology ({RSLDE})

Spirulina is a blue alga belonging to the class of Cyanobacteria. This alga is characterized by a high content of phycocyanin (PC), a blue photosynthetic pigment belonging to the phycobiliprotein family. As natural dye, PC has a lot of industrial applications, in several fields such as the cosmetic, food, and textile sectors. It is also used in the biomedical field as a fluorescent marker. Anti-inflammatory, nephroprotective, and hepatoprotective properties are also reported, probably related to its antioxidant activity. However, the extraction of phycobiliproteins from cyanobacteria is a very complicated procedure due to the extreme resistance of the wall of the cellular aggregates that make up spirulina. In literature, several procedures have been used to cause rupture of cell envelopes, through cycles of freezing/thawing, sonication, and rupture of the cell wall with lysozyme. However, all these methods do not guarantee a high quality of the extract, due to the complexity of the mixture obtained. In order to improve the yield of PC and to reduce the extraction process time, in this work, the conventional extraction by sonication is compared with a green innovative extraction technique, the rapid solid liquid dynamic extraction (RSLDE). This technique can generate a pressure and a consequent depression on the matrix to be extracted. The final extract was immediately frozen at −20°C and then lyophilized. UV–Vis spectrophotometric analysis and acrylamide gel electrophoresis are performed to evaluate the extraction efficiency and purity of PC

Supercritical fluid extraction of pyrethrins from pyrethrum flowers (Chrysanthemum cinerariifolium) compared to traditional maceration and cyclic pressurization extraction

In this work, a comparison between three extraction processes, including traditional maceration in n-hexane and ethyl alcohol, supercritical fluid extraction (SFE) and cyclically pressurized extraction known as rapid solid-liquid dynamic extraction (RSLDE), has been carried out for the extraction of pyrethrins, predominantly nonpolar natural compounds with insecticidal properties found in pyrethrum, an extract of certain species of chrysanthemums. Pyrethrins are often used in household insecticides and for the control of parasites on pets or livestock. Maceration is the cheapest method, but the values of the percent of extracted material compared to the weight of the dried flowers are lower. The extraction with supercritical CO2 is less efficient than the Naviglio extractor, but it has the advantage of not requiring the use of solvents. Consequently, all three techniques are valid for the extraction of compounds from pyrethrum flowers. The results obtained show that by suitably varying the parameters of the three extraction procedures, it is possible to obtain pyrethrin extracts for use in the production of low toxicity insecticides for warm-blooded animals and low pollution. In particular, extraction with supercritical CO2 presents an additional advantage; although oleoresin is a natural product, its extraction involves the use of solvents, while SFE is a highly efficient extraction process due to the use of CO2 in the supercritical phase without the use of solvents. On the other hand, the Naviglio extractor is an inexpensive technique and requires a minimum energy loss when compared to the extraction with supercritical fluids. Thus, the latter is more convenient on an industrial level but is not universally applicable. Nevertheless, the supercritical extraction can be used as a medium detergent of the oleoresin produced to avoid residues of the solvents left during the extraction process. Therefore, for demonstration purposes, for the SFE CO2 extraction process, numerical simulations have been performed, allowing for helpful results to optimize the process for further tests