Identification of the Origin of Chondroitin Sulfate in "Health Foods"

Multicomponent analysis of dietary supplements containing glucosamine and chondroitin: comparative low- and high-field NMR spectroscopic study

With the prevalence of glucosamine- and chondroitin-containing dietary supplements for people with osteoarthritis in the marketplace, it is important to have an accurate and reproducible analytical method for the quantitation of these compounds in finished products. NMR spectroscopic method based both on low- (80 MHz) and high- (500-600 MHz) field NMR instrumentation was established, compared and validated for the determination of chondroitin sulfate and glucosamine in dietary supplements. The proposed method was applied for analysis of 20 different dietary supplements. In the majority of cases, quantification results obtained on the low-field NMR spectrometer are similar to those obtained with high-field 500-600 MHz NMR devices. Validation results in terms of accuracy, precision, reproducibility, limit of detection and recovery demonstrated that the developed method is fit for purpose for the marketed products. The NMR method was extended to the analysis of methylsulfonylmethane, adulterant maltodextrin, acetate and inorganic ions. Low-field NMR can be a quicker and cheaper alternative to more expensive high-field NMR measurements for quality control of the investigated dietary supplements. High-field NMR instrumentation can be more favorable for samples with complex composition due to better resolution, simultaneously giving the possibility of analysis of inorganic species such as potassium and chloride.

Effects of chondroitin sulfate oligosaccharides on osteoclast differentiation of RAW264 cells, and myotube differentiation of C2C12 cells

Chondroitin sulfate (CS) is a glycosaminoglycan, and CS derived from various animal species is used in drugs and food supplements to alleviate arthralgia. The CS is a high molecular weight compound, and hydrolysis of CS by intestinal microbiota is thought to be required for absorption in mammalians. Chondroitin sulfate oligosaccharides (Oligo-CS) are produced by hydrolysis with subcritical water from CS isolated from a species of skate, Raja pulchra for the improvement of bioavailability. The present study conducted in vitro experiments using murine cell lines, to compare the biological activities of Oligo-CS and high molecular weight CS composed with the similar disaccharide isomer units of D-glucuronic acid and N-acetyl-D-glucosamine (CS-C). The results show that Oligo-CS inhibits osteoclast differentiation of RAW264 cells significantly at lower concentrations than in CS. The cell viability of a myoblast cell line, C2C12 cells, was increased when the cells were grown in a differentiated medium for myotubes with Oligo-CS, where there were no effects on the cell viability in CS. These results suggest that in vitro Oligo-CS exhibits stronger bioactivity than high-molecular weight CS.

Regulatory science of natural products

Foods and pharmaceuticals play key roles in public health and welfare and ensuring that these products meet their quality assurance standards is a top priority in health and medical care. Quality assurance of natural products is essential in pharmaceutical sciences because the outset of a medicine is a natural, crude drug. Regulatory science underpins scientific regulations and is closely related to the quality assurance of foods and pharmaceuticals to ensure their safety and efficacy. During my time at the National Institute of Health Sciences, Japan, from 1986 to present, the regulatory science of natural products has been my main research focus. This review discusses 24 studies related to the regulatory science of natural food additives, 26 related to foods, 23 related to borderline products, 16 related to illicit psychotropic mushrooms, plants, and agents, and 57 related to herbal medicines. In later sections, the regulatory science for ethical Kampo products with new dosage forms and herbal medicines that use Kampo extracts as active pharmaceutical ingredients are discussed. My experience from the early twenty-first century in research projects on the bioequivalence of Kampo products and the development of ephedrine alkaloid-free Ephedra Herb extract demonstrate that regulatory science is crucial for developing new drugs.

Preparation and characterization of chondroitin sulfate from large hybrid sturgeon cartilage by hot-pressure and its effects on acceleration of wound healing

In this paper, a combination of hot-pressure, enzymatic hydrolysis and membrane separation process is used for efficiently and environmentally friendly extraction of chondroitin sulfate (CS) from large hybrid sturgeon cartilage, namely, HPCS. The recovery and yield of CS were 93.68% and 36.47% under the optimized conditions. Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and high-performance liquid chromatography (HPLC) indicated that the HPCS was composed of monosulfated disaccharides in position 6 and 4 of the N-acetyl-D-galactosamine (58.38% and 27.34%, respectively) and nonsulfated disaccharide (14.29%), which was similar to the composition of CS extracted by dilute alkali-enzymatic hydrolysis-chemical precipitation from large hybrid sturgeon cartilage (SCS). The wound healing results indicated that HPCS could promote cell migration and proliferation, alleviate inflammation and facilitate angiogenesis, which results in its excellent wound treatment activity. These results provide theoretical and practical significance for the production and application of chondroitin sulfate.

Characterization of chondroitin sulfates isolated from large hybrid sturgeon cartilage and their gastroprotective activity against ethanol-induced gastric ulcers

Sturgeon cartilage, which is rich in chondroitin sulfate (CS), is usually discarded during sturgeon utilization. In this paper, CS was isolated from large hybrid sturgeon skull and backbone and named SCS and BCS, respectively. Their structures were investigated via Fourier transform infrared (FT-IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and high performance liquid chromatography (HPLC). The average molecular weights of SCS and BCS were ~ 30-44 kDa. Disaccharide analysis indicated that SCS and BCS had similar chemical structures and were composed of ΔUA-[1 → 3]-GalNAc (ΔDi0S, 14.71%, 16.04%), ΔUA-[1 → 3]-GalNAc-4 s (ΔDi4S, 32.01%, 37.78%) and ΔUA-[1 → 3]-GalNAc-6 s (ΔDi6S, 53.27%, 46.18%). The gastroprotective effect of SCS and BCS were studied using a rat model of ethanol-induced gastric ulcers. Both SCS and BCS had apparent gastroprotective activity and their ulcer inhibition rate reached ~ 35%-45%, which was similar to that of omeprazole (~41%). These results provide useful strategies for the high-value utilization of sturgeon cartilage.

Functions of, and replenishment strategies for, chondroitin sulfate in the human body

Chondroitin sulfate (CS) belongs to a class of molecules called glycosaminoglycans (GAGs). These are long, linear chains of polysaccharides comprising alternating amino sugars and hexuronic acid. Similar to other GAGs, CS is important in a multitude of biological activities. Alteration of CS levels has been implicated in several pathological conditions, including osteoarthritis (OA) and other inflammatory diseases, as well as physiological conditions, such as aging. Therefore, devising replenishment strategies for this molecule is an important area of research. In this review, we discuss the nature of CS, its function in different organs, and its implications in health and disease. We also describe different methods for the exogenous administration of CS.

Quality Assessment of Medicinal Product and Dietary Supplements Containing Vitex agnus-castus by HPLC Fingerprint and Quantitative Analyses

In this study, we aimed to evaluate the quality of 11 products sold in Japan (one medicinal product and 10 dietary supplements) containing/claiming to contain chasteberry extract (fruit of Vitex agnus-castus L.) using HPLC fingerprint (15 characteristic peaks), quantitative determination of chemical marker compounds, and a disintegration test. The HPLC profile of the medicinal product was similar to that of the reference standard of V. agnus-castus fruit dry extract obtained from European Directive for the Quality of Medicines (EDQM), whereas the profiles of some dietary supplements showed great variability, such as different proportions of peaks or lack of peaks. Results of the principal component analysis of the fingerprint data were consistent with those of the HPLC profile analysis. The contents of two markers, agnuside and casticin, in dietary supplements showed wide variability; this result was similar to that achieved with the HPLC fingerprint. In particular, agnuside and/or casticin was not detected in two dietary supplements. Furthermore, one dietary supplement was suspected to be contaminated with V. negundo, as evidenced from the results of agnuside to casticin ratio and assay of negundoside, a characteristic marker of V. negundo. Results of the disintegration test showed poor formulation quality of two dietary supplements. These results call attention to the quality problems of many dietary supplements, such as incorrect or poor-quality origin, different contents of the active ingredient, and/or unauthorized manufacturing procedures.

Chondroitin Sulfate Safety and Quality

The industrial production of chondroitin sulfate (CS) uses animal tissue sources as raw material derived from different terrestrial or marine species of animals. CS possesses a heterogeneous structure and physical-chemical profile in different species and tissues, responsible for the various and more specialized functions of these macromolecules. Moreover, mixes of different animal tissues and sources are possible, producing a CS final product having varied characteristics and not well identified profile, influencing oral absorption and activity. Finally, different extraction and purification processes may introduce further modifications of the CS structural characteristics and properties and may lead to extracts having a variable grade of purity, limited biological effects, presence of contaminants causing problems of safety and reproducibility along with not surely identified origin. These aspects pose a serious problem for the final consumers of the pharmaceutical or nutraceutical products mainly related to the traceability of CS and to the declaration of the real origin of the active ingredient and its content. In this review, specific, sensitive and validated analytical quality controls such as electrophoresis, eHPLC (enzymatic HPLC) and HPSEC (high-performance size-exclusion chromatography) able to assure CS quality and origin are illustrated and discussed.

Dioxin concentrations in dietary supplements containing animal oil on the Japanese market between 2007 and 2014

We determined the concentrations of dioxins (polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls) in 46 dietary supplement products, containing the oil of fish, marine mammals, or egg yolk, on the Japanese market between 2007 and 2014. Dioxins were detected in 43 of the 46 products tested at concentrations from 0.00015 to 67 pg TEQ/g. The highest concentration of dioxins was found in a shark liver oil product which varied insignificantly in five batches collected over a two-year period. The dioxin intakes from these five batches reached 2.3-2.8 pg TEQ/kg bw/day, or 58%-70%, respectively, of the Japanese tolerable daily intake (TDI) of 4 pg TEQ/kg bw/day. However, the dioxin intakes from most of the other products tested were less than 5% of the TDI. Although rare, supplements based on animal oils may contain relatively high concentrations of dioxins, leading to a substantial increase in dioxin intakes.

A multi-analytical approach to better assess the keratan sulfate contamination in animal origin chondroitin sulfate

Chondroitin sulfate is a glycosaminoglycan widely used as active principle of anti-osteoarthritis drugs and nutraceuticals, manufactured by extraction from animal cartilaginous tissues. During the manufacturing procedures, another glycosaminoglycan, the keratan sulfate, might be contemporarily withdrawn, thus eventually constituting a contaminant difficult to be determined because of its structural similarity. Considering the strict regulatory rules on the pureness of pharmaceutical grade chondrotin sulfate there is an urgent need and interest to determine the residual keratan sulfate with specific, sensitive and reliable methods. To pursue this aim, in this paper, for the first time, we set up a multi-analytical and preparative approach based on: i) a newly developed method by high performance anion-exchange chromatography with pulsed amperometric detection, ii) gas chromatography-mass spectrometry analyses, iii) size exclusion chromatography analyses coupled with triple detector array module and on iv) strong anion exchange chromatography separation. Varied KS percentages, in the range from 0.1 to 19.0% (w/w), were determined in seven pharmacopeia and commercial standards and nine commercial samples of different animal origin and manufacturers. Strong anion exchange chromatography profiles of the samples showed three or four different peaks. These peaks analyzed by high performance anion-exchange with pulsed amperometric detection and size exclusion chromatography with triple detector array, ion chromatography and by mono- or two-dimensional nuclear magnetic resonance revealed a heterogeneous composition of both glycosaminoglycans in terms of sulfation grade and molecular weight. High molecular weight species (>100 KDa) were also present in the samples that counted for chains still partially linked to a proteoglycan core.

Qualitative and Quantitative Evaluation of Drug and Health Food Products Containing Red Vine Leaf Extracts on the Japanese Market

Red vine leaf extracts (RVLEs) have traditionally been used for leg wellness and are now standardized to be used as OTC drugs in Europe. In Japan, one brand of RVLE products was recently approved as a direct OTC drug, and RVLEs are still used as ingredients in health food products. Since there is no mandated criterion for the quality of health food products in Japan, the consistent quality and composition of these products are not assured. Here we analyzed OTC drug and health food products containing RVLEs with different lot numbers by LC/MS. Subsequent multivariate analyses clearly indicated that the quality of the health food products was highly variable compared to that of the drug products. Surprisingly, the component contents in the health foods were different even within a same lot in a same brand. The quantitative analyses of flavonols and stilbene derivatives in the drugs and health foods indicated that the concentration of each substance was kept constant in the drugs but not in the health foods. These results strongly indicated that the quality of RVLEs as a whole was not properly controlled in the manufacturing process of health foods. Since RVLE is an active ingredient with pharmaceutical evidences and is used for drugs, the proper regulation for ensuring the consistent quality of RVLEs from product to product would be recommended even in the health foods.

Degradation of chondroitin sulfate by the gut microbiota of Chinese individuals

Oral preparations of chondroitin sulfate (CS) have long been used as anti-osteoarthritis (anti-OA) drugs. However, little is known about the degradation of CS by human gut microbiota. In the present study, degradation profiles of CSA (the main constituent of CS drugs) by the human gut microbiota from six healthy subjects were investigated. Each individual's microbiota had differing degradation activities, but ΔUA-GalNAc4S was the end product in all cases. To elucidate the mechanisms underlying this phenomenon, different CSA-degrading bacteria were isolated from each individual's microbiota and tested for CSA degradation. In addition to Bacteroides thetaiotaomicron J1, Bacteroides thetaiotaomicron 82 and Bacteroides ovatus E3, a new CSA-degrading bacterium, Clostridium hathewayi R4, was isolated and characterized. Interestingly, at least two different CSA-degrading species were identified from each individual's gut microbiota. Predictably, these functional bacteria also had differing degradation rates, but still generated the same end product, ΔUA-GalNAc4S. In addition, the human fecal isolates produced different degradation profiles for CSC, CSD, and CSE, suggesting that CS could be readily metabolized to varying extents by diverse microbial consortiums, which may help to explain the poor bioavailability and unequal efficacy of CS among individuals in OA treatment.

Heparin and related polysaccharides: synthesis using recombinant enzymes and metabolic engineering

Glycosaminoglycans are linear anionic polysaccharides that exhibit a number of important biological and pharmacological activities. The two most prominent members of this class of polysaccharides are heparin/heparan sulfate and the chondroitin sulfates (including dermatan sulfate). These polysaccharides, having complex structures and polydispersity, are biosynthesized in the Golgi of most animal cells. The chemical synthesis of these glycosaminoglycans is precluded by their structural complexity. Today, we depend on food animal tissues for their isolation and commercial production. Ton quantities of these glycosaminoglycans are used annually as pharmaceuticals and nutraceuticals. The variability of animal-sourced glycosaminoglycans, their inherent impurities, the limited availability of source tissues, the poor control of these source materials, and their manufacturing processes suggest a need for new approaches for their production. Over the past decade, there have been major efforts in the biotechnological production of these glycosaminoglycans. This mini-review focuses on the use of recombinant enzymes and metabolic engineering for the production of heparin and chondroitin sulfates.

Disintegration Test of Health Food Products Containing Ginkgo Biloba L. or Vitex Agnus-Castus L. in the Japanese Market

For many years now, a number of Western herbs have been widely used in health food products in Japan and as pharmaceuticals in Europe. There are few or no mandated criteria concerning the quality of these herbal health food products, thus clarification is warranted. Here, we performed disintegration tests of 26 pharmaceutical and health food products containing the Western herbs ginkgo leaf and chaste tree fruit, in accord with the Japanese Pharmacopoeia. All eight pharmaceutical herbal products found in the European market completely disintegrated within the defined test time, and 11 of the 18 tested herbal products distributed as health foods in Japan disintegrated. Among the incompatible products identified in the Pharmacopoeia test, some products remained intact after incubation in water for 60 min. To ensure the efficacy of Western herbal products sold as health food in Japan, quality control, including disintegration, is therefore recommended, even though these products are not regulated under the Pharmaceutical Affairs Law.

Discrepancies in composition and biological effects of different formulations of chondroitin sulfate

Osteoarthritis is a common, progressive joint disease, and treatments generally aim for symptomatic improvement. However, SYmptomatic Slow-Acting Drugs in Osteoarthritis (SYSADOAs) not only reduce joint pain, but slow structural disease progression. One such agent is chondroitin sulfate—a complex, heterogeneous polysaccharide. It is extracted from various animal cartilages, thus has a wide range of molecular weights and different amounts and patterns of sulfation. Chondroitin sulfate has an excellent safety profile, and although various meta-analyses have concluded that it has a beneficial effect on symptoms and structure, others have concluded little or no benefit. This may be due, at least partly, to variations in the quality of the chondroitin sulfate used for a particular study. Chondroitin sulfate is available as pharmaceutical- and nutraceutical-grade products, and the latter have great variations in preparation, composition, purity and effects. Moreover, some products contain a negligible amount of chondroitin sulfate and among samples with reasonable amounts, in vitro testing showed widely varying effects. Of importance, although some showed anti-inflammatory effects, others demonstrated weak effects, and some instances were even pro-inflammatory. This could be related to contaminants, which depend on the origin, production and purification process. It is therefore vitally important that only pharmaceutical-grade chondroitin sulfate be used for treating osteoarthritis patients.

Analysis of chondroitin sulfate from different sources of cartilage by electrophoretically mediated microanalysis

An electrophoretically mediated microanalysis protocol for the determination of different chondroitin sulfate origins was developed.

Enantiomeric determination of DOPA in dietary supplements containing Mucuna pruriens by liquid chromatography/mass spectrometry

We developed a simple and rapid liquid chromatography/mass spectrometry (LC/MS) method for the enantiomeric determination of DOPA in dietary supplements containing Mucuna pruriens. L- and D-DOPA were ultrasonically extracted with 1% formic acid aqueous solution. The isolated extracts were analyzed by LC/MS using a Crownpak CR (-) column at 30℃. The mass spectrometer was operated in the positive mode of electrospray ionization, and the mobile phase was aqueous formic acid (pH 2.0). L-DOPA-ring-d3 was used as an internal standard. The method was validated for a dietary supplement spiked with L- and D-DOPA at 50 and 500 μg/g, respectively, and the recoveries of the DOPA enantiomers were between 97.5% and 101.3%. Relative standard deviation values of repeatability and intermediate precision were less than 7%. The method was applied to 14 dietary supplements. L-DOPA was detected in these supplements in the range of 0.88-12.8 mg/unit. D-DOPA was not detected.

Detection of keratan sulfate by immunological methods in commercial chondroitin sulfate preparations

Chondroitin sulfate (CS), a well known nutraceutical, and keratan sulfate (KS) are glycosaminoglycans involved in the structure of cartilage proteoglycan, aggrecan. Since CS is extracted from cartilage, there may be a possibility that purified CS is contaminated with small amount of KS. A total of 15 samples, including four samples of CS as laboratory reagents, one sample of CS as a food additive and ten samples of dietary supplements containing CS were examined to detect KS in these samples by using immunodiffusion and enzyme-linked immunosorbent assay (ELISA) with anti-KS monoclonal antibody (IgM). With the exception of three samples of CS as laboratory reagents, all samples were found to contain varying amounts of KS. It was concluded that both the immunodiffusion, a quick one-step method, and ELISA for quantification, are reliable methods to detect KS contamination in CS products.

Extraction of Chondroitin Sulfate from Tilapia Byproducts with Ultrasonic-Microwave Synergistic

The optimum conditions for the extraction and separation of chondroitin sulfate from tilapia (Oreochromis niloticus) byproducts were studied in the paper. The chondroitin sulfate was extracted by the combination of ultrasonic and microwave. On the basis of the single factor tests, the response surface methodology was taken to study the optimum process of extraction. Results show that the best conditions for the extraction and separation of chondroitin sulfate from tilapia byproducts are: the ultrasonic power is 50W, the microwave power is 98W, the extraction time is 120s, the ratio of solid to liquid is 1:50 (g/mL), and under these conditions, the extraction rate of chondroitin sulfate is 2.513%.

Determination and Identification of Chondroitin Sulfate from Tilapia Byproducts

In order to probe the structure of chondroitin sulfate (CS) from tilapia fish, the CS was extracted from tilapia (Oreochromis niloticus) byproducts with the combination of ultrasonic and microwave, some means including high performance liquid chromatography (HPLC), infrared spectra (IR) and nuclear magnetic resonance (NMR) were used in this paper. The data of HPLC exhibited that the obtained chondroitin sulfate is of highly purity (98.78%). IR and NMR spectra indicated that the sample consisted of both chondroitin-4-sulfate and chondroitin-6-sulfate, and the proportion of chondroitin-6-sulfate was higher than chondroitin-4-sulfate.

The use of multi-element stable isotope analysis to monitor the origin of chondroitin sulfates

Continuous-flow isotope ratio mass spectrometry (CF-IRMS) of deuterium, carbon, nitrogen, oxygen and sulfur has been used to analyse samples of pure chondroitin sulfates from known animal sources (shark, squid, salmon, pig and bovine). There is a need to control the origin of this dietary supplement, which is extracted from several types of animals: for traditional, ethical, or economic reasons, a given source of natural products of animal origin can be preferred to another, and can therefore have a different price. Twenty-three samples collected in Europe and Asia were analysed by IRMS. The results, especially the isotopic deviations of sulphur, oxygen and deuterium, show a significant discrimination between marine and terrestrial origins of this compound which will provide a convenient and efficient way to control the declared sources in the market. The differences observed between origins are further discussed.

Isolation and characterization of chondroitin sulfates from sturgeon (Acipenser sinensis) and their effects on growth of fibroblasts

Chondroitin sulfate (CS) is a glycosaminoglycan that composed of hexosamine (D-galactosamine) and hexuronic acid (D-glucuronic acid) unit arranged in an alternating unbranched sequence. CS is an essential component of the extracellular matrix (ECM) of connective tissue. It is mainly covalently attached to core proteins in the form of proteoglycans so that it exhibits specific interactions with proteins for cell growth, differentiation, division and migration. In this study, CSs were purified from the cartilage and backbone of sturgeon (Acipenser sinensis). To characterize their biochemical properties, we performed disaccharide compositional analysis after chondroitinase ABC digestion, high performance size exclusion chromatography (HPSEC) and (1)H-NMR spectroscopy. We also investigated the effects of CSs on fibroblast proliferation and adhesion to determine whether wound healing was accelerated in vitro and proliferation of different mitogen-activated protein kinases (MAPK) signaling pathways was facilitated. The CS purified from sturgeon cartilage was primarily composed of 4-sulfated CS (88.8%) and sturgeon backbone CS contains more than 60% 6-sulfated CS. The average molecular weights of CSs obtained from sturgeon cartilage and backbone were found to be 8 and 43 kDa, respectively. Our results showed that both CSs are able to increase cell adhesion, induce proliferation and migration on fibroblasts and may accelerate wound healing by inducing MAPK signaling pathways.

The quality of commercially available nutraceutical supplements and food sources

OBJECTIVES

Nutraceuticals are components of dietary origin, with claimed beneficial therapeutic activities. The quality of nutraceuticals is paramount for efficacy and safety, and it includes quality of raw materials, different available chemical forms, complex products, lack of substitution of inappropriate materials, and the absence of contaminants. The aim of this review is to investigate the extent of substandard formulated and raw material nutraceuticals, and to highlight any consequent health concern.

KEY FINDINGS

Reports of the quality of raw materials have revealed wide variations, often as a result of lack of clear regulatory definitions with respect to size of polymeric entities and also presence of glycosidic and salt forms. Published evaluations of over 70 formulations of 25 different nutraceuticals revealed variable quality; no nutraceutical showed consistent high quality, but a number revealed consistent low quality, thereby making the case for closer regulation of manufacturers. Whole food sources have also been shown to be widely variable in constituent levels. The effect of different formulations requires consideration, as the different types have been shown to have marked effects on bioavailability.

SUMMARY

The poor quality of commercially available nutraceuticals has been highlighted. In addition, incidences of side effects and drug interactions are increasing, as consumption of nutraceuticals rises. Pharmacists and health practitioners need to be aware of the scientific literature to advise accordingly.

Quality of different chondroitin sulfate preparations in relation to their therapeutic activity

Objectives

Chondroitin sulfate is currently recommended by the European League Against Rheumatism (EULAR) as a SYSADOA (symptomatic slow acting drug for osteoarthritis) in Europe in the treatment of knee and hand osteoarthritis based on research evidence and meta-analysis of numerous clinical studies. Furthermore, recent clinical trials demonstrated its possible structure-modifying effects. Chondroitin sulfate, alone or in combination with glucosamine or other ingredients, is also utilized as a nutraceutical in dietary supplements in Europe and the USA. However, it is derived from animal sources by extraction and purification processes. As a consequence, source material, manufacturing processes, the presence of contaminants and many other factors contribute to the overall biological and pharmacological actions of these agents. We aim to review the quality control of chondroitin sulfate in pharmaceutical-grade preparations and nutraceuticals.

Key findings

Pharmaceutical-grade formulations of chondroitin sulfate are of high and standardized quality, purity and properties, due to the stricter regulations to which this drug is subjected by local national health institutes as regards production and characteristics. On the contrary, as several published studies available in literature indicate, the chondroitin sulfate quality of several nutraceuticals is poor. Additionally, there are no definite regulations governing the origin of the ingredients in these nutraceuticals and the origin of the ingredients in natural products is the most important factor ensuring quality, and thus safety and efficacy, in particular for chondroitin sulfate, due to its extraction from different sources.

Conclusions

Due to the poor chondroitin sulfate quality of some nutraceuticals, we conclude that stricter regulations regarding their quality control should be introduced to guarantee the manufacture of high quality products for nutraceutical utilization and to protect customers from low-quality, ineffective and potentially dangerous products. There is a need for specific and accurate analytical procedures, which should be enforced to confirm purity and label claims both for raw materials and finished chondroitin sulfate products, and also to govern the origin of ingredients. Until these stricter regulations are in place, then it is strongly recommended that pharmaceutical-grade chondroitin sulfate is used rather than food supplements.

Chondroitin sulphate: a complex molecule with potential impacts on a wide range of biological systems

Chondroitin sulphate (CS) is widely consumed orally by humans, and non-humans as it is believed to be beneficial for those with joint-related pathologies. Data concerning the functions of chondroitin sulphate in this, and other, biological systems are being actively extended. However, it is important to appreciate that chondroitin sulphate molecules represent a heterogeneous population the structure of which varies with source. As commercially available chondroitin sulphate is derived from a range of sources, and the molecular functions of chondroitin sulphate depend upon the structure, there are a range of structures available with differing potential for therapeutic impacts on a range of pathologies. While the safety of CS is not presently in doubt, poor quality finished products have the potential to compromise clinical and lab-based studies and will fail to give consumers all of the benefits available. Major parameters including bioavailability and uptake have been studied but it is clear that significant challenges remain in the identification of composition, sequence and size impacts on function, understanding how the consumed material is altered during uptake and travels to a site of action and how it exerts an influence on biological processes. If we understand these factors it may be possible to predict impacts upon biological processes and identify specific chondroitin sulphate structures which may target specific pathologies.