Effects of Dietary Organic, Inorganic, and Nanoparticulate Zinc on Rainbow Trout, Oncorhynchus mykiss Larvae

Dietary algal-sourced zinc nanoparticles promote growth performance, intestinal integrity, and immune response of Nile tilapia (Oreochromis niloticus)

BACKGROUND

Trace elements play a crucial role in fish nutrition, with zinc (Zn) being one of the most important elements. BIO-sourced zinc nanoparticles were synthesized using the green microalga Pediastrum boryanum (BIO-ZnNPs, 29.35 nm). 30 or 60 mg/ kg dry feed of the BIO-ZnNPs (BIO-ZnNPs30 and BIO-ZnNPs60) were mixed with the Nile tilapia (Oreochromis niloticus) basal diet and fed to the fish for 8 weeks to evaluate their impact on fish growth, digestion, intestinal integrity, antioxidative status, and immunity.

RESULTS

A significant enhancement was observed in all investigated parameters, except for the serum protein profile. BIO-ZnNPs at 60 mg/kg feed elevated the activities of reduced glutathione (GSH) and catalase (CAT), enzymatic antioxidants, but did not induce oxidative stress as reflected by no change in MDA level. Fish intestinal immunity was improved in a dose-dependent manner, in terms of improved morphometry and a higher count of acid mucin-producing goblet cells. Interleukin-8 (IL-8) was upregulated in BIO-ZnNPs30 compared to BIO-ZnNPs60 and control fish groups, while no significant expressions were noted in tumor necrosis factor-alpha (TNFα), nuclear factor kappa B (NFkB), and Caspase3 genes.

CONCLUSION

Overall, BIO-ZnNPs inclusion at 60 mg/kg feed showed the most advantage in different scenarios, compared to BIO-ZnNPs at 30 mg/kg feed. The positive effects on growth and intestinal health suggest that BIO-ZnNPs supplementation of aquafeeds has many benefits for farmed fish.

Fe-NPs and Zn-NPs: Advancing Aquaculture Performance Through Nanotechnology

Aquaculture is a growing industry facing several challenges, including disease control, water quality management, and sustainable feed production. One potential solution to these challenges is the use of trace elements such as iron (Fe) and zinc (Zn), either in their conventional form or as nanoparticles (NPs). Aquatic animals need these micronutrients for normal growth, physiological processes, and overall health. In marine species, iron boosts development, immunity, and disease resistance. At the same time, zinc enhances metabolism, synthesizes essential enzymes, and produces hormones that play a part in defenses, growth, reproduction, and antioxidative activities. According to this review, species-specific requirements by different Fe and Zn compounds have all emphasized the impacts on animal growth and development, antioxidant capacity, reproductive efficiency, and immunological response. However, NPs of Fe and Zn have been found to have higher bioavailability and efficacy than conventional forms. This work examines the effects of applications of Fe and Fe nanoparticles (Fe-NPs) and Zn and Zn nanoparticles (Zn-NPs) in aquaculture. However, the source of Fe and Zn in aquaculture species and administration volume may significantly impact efficacy. Nanotechnology boosts the positive benefits of Fe and Zn by converting them to their nanoforms (Fe-NPs) and (Zn-NPs), which are better used by animals and have a broader intake range. As a result, Fe-NPs and Zn-NPs offer an effective method for using nutrients in aquaculture.

Comparative Effect of Chemical and Green Zinc Nanoparticles on the Growth, Hematology, Serum Biochemical, Antioxidant Parameters, and Immunity in Serum and Mucus of Goldfish, Carassius auratus (Linnaeus, 1758)

Recently, nano feed supplement research has great attention to improving healthy aquatic production and improving the aquatic environment. With the aims of the present study, chemical and green synthesized nanoparticles are characterized by various instrumentation analyses, namely UV-Vis spectrophotometry (UV-Vis), X-ray diffraction (XRD), Fourier transform infra-red (FTIR) spectroscopy, and scanning electron microscope (SEM). After characterization analysis of these nanoparticles utilized in aquatic animals, the composition ratio is as follows: controls (without ZnO-NPs (0 mg/L)), T1 (0.9 mg/L ZnO-NPs), T2 (1.9 mg/L ZnO-NPs), T3 (0.9 mg/L GZnO-NPs), T4 (1.9 mg/L GZnO-NPs). SEM investigation report demonstrates that the structure of the surface of green synthesized zinc oxide nanoparticles (GZnO-NPs) was conical shape and the size ranging was from 60 to 70 nm. Concerning hematological parameters, the quantity of hemoglobin increased in different doses of green zinc nanoparticles, but the values of MCV and MCH decreased somewhat. However, this decrease was the highest in the T2 group. Total protein and albumin decreased in T2 and triglyceride, cholesterol, glucose, cortisol, creatinine, and urea increased, while in T3 and T4 groups, changes in biochemical parameters were evaluated as positive. Mucosal and serum immunological parameters in the T2 group showed a significant decrease compared to other groups. In zinc nanoparticles, with increasing dose, oxidative damage is aggravated, so in the T2 group, a decrease in antioxidant enzymes and an increase in MDA were seen compared to other groups. In this regard, the concentration of liver enzymes AST and ALT increased in the T2 group compared with control and other groups. This can confirm liver damage in this dose compared with control and other groups. This research work suggests that green synthesized form of zinc nanoparticles in higher doses have less toxic effects in comparison to the chemical form of zinc nanoparticles and can act as suitable nutrient supplements in aquatic animals.

Optimal dietary zinc inclusion improved growth performance, serum antioxidant capacity, immune status, and liver lipid and glucose metabolism of largemouth bass (Micropterus salmoides)

This study was conducted to ascertain the effect of dietary Zn on growth and health status of juvenile largemouth bass (Micropterus salmoides). Six experimental diets with Zn level of 50.17, 56.74, 73.34, 86.03, 123.94, and 209.20 mg/kg, respectively were compounded using complex amino acid-chelated zinc, and were fed to juvenile fish (5.50 ± 0.10 g) for 70 d. The specific growth rate (SGR) varied with dietary Zn level in a quadratic model and peaked at the 73.34 mg/kg group, while the feeding rate exhibited an opposite trend (P < 0.05). The condition factor, hepatosomatic index and mesenteric fat index all exhibited a tendency similar with SGR (P < 0.05). Dietary Zn level affected serum total proteins, urea, triglycerides, and glucose (P < 0.05). Serum Zn and copper levels linearly increased with dietary Zn level, while serum iron and manganese showed the opposite trend. Serum superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) increased with dietary Zn level and reached a plateau at 86.03 mg/kg. Serum complement component 3 (C3), IgM, and lysozyme also were enhanced by 73.34 mg/kg Zn. Body protein content increased with zinc level up to 73.34 mg/kg, and then remained steadily. As dietary Zn level increased, hepatic lipid level increased and then reached a plateau at 86.03 mg/kg group, while glycogen increased linearly. Moreover, gene expression related to lipid and glycogen metabolism from liver transcriptome further explained the liver lipid and glycogen variations. To conclude, a dietary Zn requirement of 76.99 mg/kg was suggested for juvenile largemouth bass to improve growth, antioxidant capacity, and immune status.

Immunomodulation, Fish Health and Resistance to Staphylococcus aureus of Nile Tilapia (Oreochromis niloticus) Fed Diet Supplemented with Zinc Oxide Nanoparticles and Zinc Acetate

Recently some metal-based nanoparticles have gained serious attention from aquaculture and the fish feed industry as feed supplements. Oral supplementation of zinc oxide nanoparticles (ZnO-NPs) in fish feed, replacing Zn acetate (conventionally used zinc), is suggested as a cost-effective and efficient approach. Our study assessed the response of Nile tilapia, Oreochromis niloticus, fingerlings after its diet supplemented with chemically synthesized ZnO-NPs and zinc acetate under controlled conditions. ZnO-NPs were chemically synthesized and characterized. Tilapia fingerlings with an average body weight of 09.12 ± 1.23 g were randomly distributed into five groups. An 8-week trial was set with control and four experimental groups. Basal diet (D1) was used as control, whereas D2, D3 and D4 comprising 20, 40, and 60 mgkg-1 ZnO-NPs supplementation were experimental diets. Additionally, D5 was composed of a basal diet supplemented with 40 mgkg-1 of conventionally used zinc acetate. Significant improvement (P < 0.05) was found in nanoparticles and Zn acetate supplemented groups as compared to control, while the 40 mgkg-1 Zn-NPs supplemented diet (D3) showed best performance in terms of health parameters, oxidative status and disease resistance. Antioxidant profiling was based on catalase, superoxide dismutase, glutathione's transferase, and malondialdehyde; hematology included Hb, WBCs, RBCs, HCT MCV, MCH and MCHC; immunological parameters comprised IgM, lysozyme activity, phagocytic activity, respiratory burst activity, cholesterol, aspartate aminotransferase, alanine aminotransferase, glucose content, and total serum proteins. We report that the D3 (40 mgkg-1 ZnO-NPs supplementation) significantly (P < 0.05) improved health-related parameters as compared to the other groups. Moreover, D3 also showed significantly decreased mortality percentage when challenged by Staphylococcus aureus, while the Zn acetate supplemented diet group showed better results as compared to control. Overall results suggest the basal diet supplemented with 40 mgkg-1 ZnO-NP for enhanced health parameters, oxidative status, immune response, and disease resistance. Hence, 40mgkg-1 ZnO-NP can be recommended to formulate the practical diet of fish to boost health improvement, immunomodulation, and resistance to bacterial disease.

Nutritional Supplementation and Enhanced Antioxidant Function by Dietary Intake of Selenoneine and Other Selenium Compounds in Red Seabream Pagrus major

Selenoneine, 2-selenyl-Nα, Nα, Nα-trimethyl-L-histidine, is the major organic selenium compound in marine fish. To characterize biological antioxidant function of selenoneine in fish, the accumulation of selenoneine and other selenium compounds, i. e., sodium selenite and selenomethionine, in the muscle and other tissues of red seabream. We reared red seabream by feeding of 1% dry pellet containing of sodium selenite, selenomethionine, or selenoneine of body weight twice a day for 4 weeks. After that, we replaced to 1% of normal commercial dry pellet of body weight twice a day for 1 week from the selenium supplementation, and tissue distribution of total selenium was determined. Selenium supplementation with selenoneine, selenomethionine, and sodium selenite enhanced selenium accumulation in the white muscle, kidney, and hepatopancreas in comparison with the control group. By the dietary intake of selenoneine, total selenium concentrations were increased in the white muscle, heart, kidney, spleen, hepatopancreas, brain, and blood cells in a dose-dependent manner during the trials after 2 weeks. Dietary intake of selenoneine as well as sodium selenite and selenomethionine reduced oxidation-reduction potential (ORP). Selenoneine concentrations in the white muscle and blood cells were accumulated for 4 weeks by the selenoneine intake, whereas selenoneine concentration was not elevated by the intake of selenomethionine and sodium selenite, suggesting that tissue selenoneine levels might be derived from only selenoneine-containing diet. The uptake factor of selenoneine from the artificial feed containing selenoneine was calculated to be 0.0062 in the white muscle and 4.0 in the blood. The half-life of total selenium in the blood cells and white muscle were estimated to be 60 days in the white muscle and 30 days in the blood.

Zinc Oxide Nanoparticles Boost the Immune Responses in Oreochromis niloticus and Improve Disease Resistance to Aeromonas hydrophila Infection

Zinc is an essential element affecting immune responses in aquatic organisms. In the present research, the immunomodulating effect of zinc oxide nanoparticles (ZnO NPs) was studied in Nile tilapia (Oreochromis niloticus). The minimum inhibitory concentration of zinc oxide nanoparticles (ZnO NPs) for Aeromonas hydrophila was estimated at 60 µg/mL. To evaluate the efficacy of ZnO NPs for improving disease resistance against A. hydrophila, three hundred fish were divided into 5 groups. Fish in the group T1 maintained on the control feed, T2 and T3 feed on ZnO at 60 and 30 µg/g, while T4 and T5 received ZnO NPs at 60 and 30 µg/g, respectively for 8 weeks. Immune responses were evaluated by determining the phagocytic activity, serum antibacterial activity, lysozymes, respiratory burst activity, and also gene expression of immunoglobin M-2, tumor necrosis factor-α, interleukin (IL)-1β, heat shock proteins, IL-10, insulin growth factor 1, transforming growth factor-β2, superoxide dismutase enzyme, and catalase enzyme genes. Results indicated that groups that received ZnO NPs have exaggerated immune response and upregulation in the most of expressed immune-related genes. After the feeding trial, all groups were experimentally infected with A. hydrophila, and the mortality rate was monitored. Among all the treated groups, a higher survival rate and disease resistance were observed for fish that received ZnO NPs at 30 and 60 µg/g. The inclusion of ZnO NPs in O. niloticus feed improves both fish immune response and disease resistance against A. hydrophila.

Nano-Nutraceuticals for Health: Principles and Applications

The use of nanotechnological products is increasing steadily. In this scenario, the application of nanotechnology in food science and as a technological platform is a reality. Among the several applications, the main use of this technology is for the development of foods and nutraceuticals with higher bioavailability, lower toxicity, and better sustainability. In the health field, nano-nutraceuticals are being used as supplementary products to treat an increasing number of diseases. This review summarizes the main concepts and applications of nano-nutraceuticals for health, with special focus on treating cancer and inflammation.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s43450-022-00338-7.

Dietary Zinc in Association with Vitamin E Promotes Growth Performance of Nile Tilapia

Zinc (Zn) and vitamin E (VE) are essential micro-nutrients that contribute a pivotal role in the physiology and nutrition of fish. An experiment was designed to know the effects of Zn and VE addition in the diet on growth and feed utilization in Nile tilapia (Oreochromis niloticus). Four diets containing Zn (80 mg/kg), VE (50 mg/kg), Zn (80 mg/kg) + VE (50 mg/kg), and without Zn and VE (control) were fed to Nile tilapia in aquaria with triplicate groups for 6 weeks. Survival, growth parameters (weight gain, WG; %WG; specific growth rate, SGR), and feed utilization (protein efficiency ratio, PER; feed conversion ratio, FCR) were calculated at the end of the feeding trial. Several hemato-biochemical parameters (hemoglobin, Hb; red blood cell, RBC; white blood cell, WBC, and glucose) and morphology of muscle were analyzed. The growth parameters (WG, %WG, and SGR) and feed utilization (FCR and PER) improved significantly in the fish fed with Zn, VE, and Zn + VE supplemented diets. There was no significant change in the values of Hb, RBC, WBC, and glucose level among different groups. Significantly improved diameter of muscle fiber, reduced distance between muscle fiber, and increased number of the nucleus and hyperplastic muscle fiber were observed in the fish fed with Zn, VE, and Zn + VE supplemented diets. These results suggested that Zn and VE can be effectively incorporated into the diets of Nile tilapia for better growth with maximum feed utilization.

Significance of extrinsic factors for the optimization of dietary cobalt supplementation in Tor putitora fingerlings

Extrinsic factors play a significant role during aquaculture feed manufacturing practices. Herein, a 90-day feeding trial was designed in triplicate under controlled environmental conditions to evaluate the efficiency of different chemical forms of dietary cobalt at different dosage levels on growth performance, hematological, and immunological indices of Tor putitora fingerlings. Firstly, cobalt chloride nanoparticles (Co-NPs) and cobalt methionine chelated complex (Co-Met) were synthesized via physical and chemical methods respectively and then characterized for their size, surface morphology, and elemental composition analysis by using X-rays diffraction spectroscopy (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Results indicated the crystalline nature of Co-NPs with spherical shape having an average size < 20 nm while Co-Met appeared as an amorphous complex with a honey-comb-like octahedral structure with an average size of 82.69 nm. Afterward, a feeding experiment was executed and fish were divided into three groups, i.e., control group (CG; fed 40% crude protein diet with no mineral added), while the other two groups were fed graded levels (0.5-3 mg/kg; increment of 0.5 mg Co/group) of Co-NPs and Co-Met supplemented diets. Statistical analysis of results by using two-way ANOVA indicated significant (P < 0.001) effect of both chemical forms, dosage levels, and their interaction level on fish indicating a dose-dependent significant effect of different chemical forms of dietary cobalt on fish. Additionally, Co-Met supplemented group of fish at supplementation level of 3 mg/kg diet showed highest growth performance, and improved hemato-immunological as compared to other experimental and control group of fish.

The Role of Zinc Microelement in Aquaculture: a Review

Trace elements are required in optimum regimes for improving the productivity and wellbeing of aquatic animals. Zinc is one of the main microelements involved in several functions in the animal's body. Zinc potentiates the metabolism function, synthesis of essential enzymes, and the formation of hormones associated with growth, reproduction, immunity, and antioxidative roles in aquatic animals. Several sources of zinc are regularly applied in aquaculture, including inorganic, organic, and nanoparticles. Many studies examined the effects of zinc supplementation in the diets of aquatic animals. The results indicated that zinc could be included in aquafeed in a dose-dependent manner. The effects of zinc depend on the dose, source, duration of feeding, animals' sizes, and experimental conditions. This article comprehensively discusses the results of relevant studies that investigated the effects of zinc on the performances of aquatic animals. The review also intended to update the academia with the previous and current status of using zinc in aquafeed. Furthermore, the article includes up-to-date outputs of relevant studies of using different zinc sources in aquafeed.

The Assessment of Dietary Organic Zinc on Zinc Homeostasis, Antioxidant Capacity, Immune Response, Glycolysis and Intestinal Microbiota in White Shrimp (Litopenaeus vannamei Boone, 1931)

This study aimed to assess dietary organic zinc on zinc homeostasis, antioxidant capacity, immune response, glycolysis and intestinal microbiota in white shrimp (Litopenaeus vannamei Boone, 1931). Six experimental diets were formulated: Control, zinc free; S120, 120 mg·kg-1 zinc from ZnSO4·7H2O added into control diet; O30, O60, O90 and O120, 30, 60, 90 and 120 mg·kg-1 zinc from Zn-proteinate added into control diet, respectively. The results showed that organic zinc significantly promoted zinc content and gene expression of ZnT1, ZIP11 and MT in the hepatopancreas and enhanced antioxidant capacity and immunity (in terms of increased activities of T-SOD, Cu/Zn SOD, PO, LZM, decreased content of MDA, upregulated expressions of GST, G6PDH, ProPO, LZM and Hemo, and increased resistance to Vibrio parahaemolyticus). Organic zinc significantly upregulated GluT1 expression in the intestine, increased glucose content of plasma and GCK, PFK and PDH activities of hepatopancreas, and decreased pyruvate content of hepatopancreas. Organic zinc improved intestinal microbiota communities, increased the abundance of potentially beneficial bacteria and decreased the abundance of potential pathogens. Inorganic zinc (S120) also had positive effects, but organic zinc (as low as O60) could achieve better effects. Overall, organic zinc had a higher bioavailability and was a more beneficial zinc resource than inorganic zinc in shrimp feeds.

Nano Zinc Versus Bulk Zinc Form as Dietary Supplied: Effects on Growth, Intestinal Enzymes and Topography, and Hemato-biochemical and Oxidative Stress Biomarker in Nile Tilapia (Oreochromis niloticus Linnaeus, 1758)

Five isonitrogenous diets were formulated to comprise two forms of zinc (Zn): convention zinc oxide named Bulk-ZnO or zinc oxide nanoparticles (Nano-ZnO) supplemented at two levels 30 and 60 mg kg^-1 compared to the control diet. Nile tilapia, Oreochromis niloticus, fingerlings (5.02-5.05 g) were fed tested diets two times a day for 84 days. The results displayed that the best growth and digestive enzyme activity (P < 0.05) were noticed in fish fed 60 mg kg^-1 Nano-ZnO. Moreover, significant (P < 0.05) improvement in intestinal topography was observed in 60 mg kg^-1 Nano-ZnO group versus other treatments. Furthermore, fish fed 30 mg kg^-1 Nano-ZnO recorded the best values of hematological indices (P < 0.05). The alanine and aspartate aminotransferase (ALT and AST) values were lower, while total serum protein, albumin, and globulin contents were clearly higher in fish fed diet that contained 30 mg kg^-1 Nano-ZnO versus other groups. The significant highest values of oxidative enzyme activity escorted with lower malondialdehyde value recorded of fish fed diet supplemented with 60 mg kg^-1 Nano-ZnO. The results indicated that inclusion of Nano-ZnO at 60 mg kg^-1 was the recommended source to enhance growth, feed utilization, amylase and lipase enzymes activity, intestinal morphology, hemato-biochemical, and oxidative response biomarkers of Nile tilapia compared with Bulk-ZnO in commercial tilapia feeds.

Optimum dietary sources and levels of selenium improve growth, antioxidant status, and disease resistance: re-evaluation in a farmed fish species, Nile tilapia (Oreochromis niloticus)

The objective of this study was to investigate the effects of sources and levels of selenium (Se) on juvenile Nile tilapia (Oreochromis niloticus). A completely randomized design involving a 2 × 3 factorial arrangement of treatments was used in this study. Organic Se (L-selenomethionine; SeMet) and inorganic Se (sodium selenite; Na₂SeO₃) were each added to the basal diet at 1, 3 and 5 mg Se/kg. The basal diet, without Se supplementation, was used as a control. There was a total of 7 experimental diets, and each was fed in triplicate to groups of fish with an initial average body weight of 13.5 g for 8 weeks. The results showed that growth performance was significantly affected by dietary sources and levels of Se (P < 0.05). Fish fed diets supplemented with SeMet of 1.0 mg Se/kg resulted in higher growth performance compared to basal diet (P < 0.05), but Na₂SeO₃ supplementation did not affect growth. The feed conversion ratio was significantly decreased as dietary sources of SeMet (P < 0.05). Interestingly, fish fed diets supplemented with both forms of Se had lower cholesterol levels than those fed the basal diet (P < 0.05). Moreover, dietary sources and levels of Se significantly increased (P < 0.05) the antioxidant enzyme activities such as lysozyme, catalase, myeloperoxidase, superoxide dismutase and glutathione peroxidase. Dietary sources and levels of Se significantly could enhance the Nile tilapia resistance against Streptococcusagalactiae infection (P < 0.05). Overall, it can be concluded that the inclusion level of 1.0 mg Se/kg of organic Se in the diet is suggested to be the optimal level for the growth performance and immune response of Nile tilapia. Therefore, dietary supplementation with Se is useful for improving growth, antioxidant status, immune response, and disease resistance.

Effect of Dietary Manganese and Zinc Levels on Growth and Bone Status of Senegalese Sole (Solea senegalensis) Post-Larvae

Essential dietary trace elements, such as zinc (Zn) and manganese (Mn), critically influence a wide range of physiological, metabolic, and hormonal processes in fish larvae and post-larvae. Despite their importance for normal fish growth and skeletal development, trace mineral nutrition has not been extensively studied in the early stages of development of fish. Post-larvae of an emergent aquaculture species, Senegalese sole (Solea senegalensis), were the subject of this study in order to better understand the effects of diet supplementation of trace minerals upon fish larval development and performance. Sole post-larvae were fed a combination of organic Mn (45 and 90 mg kg^-1 feed) and organic Zn (100 and 130 mg kg^-1 feed) and survival, growth, mineral deposition rates, and vertebral bone status were assessed. Our results showed that although no significant effect was found on the growth performance of Senegalese sole post-larvae, Mn and Zn supplementation to a commercial microdiet for marine fish larvae at higher dietary levels (Mn at 90 mg kg^-1 and Zn at 130 mg kg^-1) improved larval survival, decreased the severity of vertebral malformations, and increased the deposition of Mn in bone.

Antioxidants in Fish Sperm and the Potential Role of Melatonin

In recent years, the effects of novel antioxidants have played an important role in the research focusing on fish cell protection. As food demand grows, aquaculture production becomes more intensive, and fish are more exposed to oxidative stress conditions, like high densities, temperature shifting, frequent fish handling and samplings, and prophylactic or disease treatments, which expose fish to a different environment. Particularly in reproduction, germ cells lose antioxidant capacity with spermatogenesis, as spermatozoa are more prone to oxidative stress. Antioxidants have been used in a variety of fish physiological problems including in reproduction and in the establishment of cryopreservation protocols. From the most used antioxidants to natural plant food and herbs, and endogenously produced antioxidants, like melatonin, a review of the literature available in terms of their effects on the protection of fish spermatozoa is presented here in a classified structure. Several direct and indirect approaches to improve gamete quality using antioxidants administration are mentioned (through feed supplementation or by adding in cryopreservation media), as well as factors affecting the efficiency of these molecules and their mechanisms of action. Special attention is given to the unclear melatonin pathway and its potential scavenger activity to prevent and counteract oxidative stress damage on fish spermatozoa.

Potential of Nanomaterial Applications in Dietary Supplements and Foods for Special Medical Purposes

Dietary supplements and foods for special medical purposes are special medical products classified according to the legal basis. They are regulated, for example, by the European Food Safety Authority and the U.S. Food and Drug Administration, as well as by various national regulations issued most frequently by the Ministry of Health and/or the Ministry of Agriculture of particular countries around the world. They constitute a concentrated source of vitamins, minerals, polyunsaturated fatty acids and antioxidants or other compounds with a nutritional or physiological effect contained in the food/feed, alone or in combination, intended for direct consumption in small measured amounts. As nanotechnology provides "a new dimension" accompanied with new or modified properties conferred to many current materials, it is widely used for the production of a new generation of drug formulations, and it is also used in the food industry and even in various types of nutritional supplements. These nanoformulations of supplements are being prepared especially with the purpose to improve bioavailability, protect active ingredients against degradation, or reduce side effects. This contribution comprehensively summarizes the current state of the research focused on nanoformulated human and veterinary dietary supplements, nutraceuticals, and functional foods for special medical purposes, their particular applications in various food products and drinks as well as the most important related guidelines, regulations and directives.