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As polysaccharide from Bletilla striata (BSP) was anticipated with mucoadhesive improvement in sodium alginate (SA) microspheres, BSP was mixed with SA to construct a composite microsphere to retain in the gastrointestinal tract for a long time. The morphological properties, particle size and thermodynamic properties of the microspheres in combination with comprehensive evaluations in the swelling properties, mucin adsorption, ex vivo and in vivo gastric retention were determined to characterize the mucoadhesion of SA-BSP blend microspheres. Results showed that the prepared microspheres were discrete and spherical. The addition of BSP increased flexibility and reduced rigidity of SA microsphere. Furthermore, the swelling property, mucin adsorption ability and the retention rate on the gastric mucosa of SA matrix were increased after blending with BSP. Mucoadhesion tests showed the SA-BSP microspheres stayed much longer in rats' stomach than the SA microsphere did. Above all, the SA-BSP microspheres with the enhanced mucoadhesion suggested being a potential drug carrier in developing the gastroretentive drug delivery system.

The oral bioavailability of many phenolic acid drugs is severely limited due to the high hydrophilicity and extensive first-pass effect induced by catechol-O-methyltransferase (COMT) metabolism. The present study investigated the inhibitory activity of the pharmaceutical excipients of extra virgin olive oil (EVOO) against COMT and evaluated the potential of a self-microemulsion loaded with a phospholipid complex containing EVOO for oral absorption enhancement of salvianolic acid B (SAB), a model phenolic acid. An in vitro COMT assay showed that EVOO could effectively inhibit enzyme activity in the rat liver cytosol. Next, the SAB phospholipid complex/self-microemulsion containing EVOO (named SP-SME1) was prepared and characterized (particle size, 243.60 ±6.96 nm and zeta potential, -23.67 ±-1.36 mV). The phospholipid complex/self-microemulsion containing ethyl oleate (EO) (named SP-SME2) was taken as the control group. Compared with free SAB, the apparent permeability coefficient (Papp value) of the two SP-SMEs significantly increased (12.0-fold and 10.90-fold). A pharmacokinetic study demonstrated that the AUC0-∞ value of SAB for the SP-SME1 group significantly increased by 4.72 and 2.82 times compared to that for free SAB (p

Tubiechong, in Chinese medicine, denotes the dried female insects of Eupolyphaga sinensis Walker (ESW) or Polyphaga plancyi Bolivar (PPB). As a traditional insect-type, in medicine, it has been historically utilized to treat bruises, fractures, amenorrhea, postpartum blood stasis, lumps and relieving pain. We herein have performed a systematic survey involving the chemical and biological studies in the past decades to reveal the value of such insect resources for their development and clinical utilization. Chemical studies indicated that Tubiechong generated many active compounds, including proteins, amino acids, peptides, fatty acids, alkaloids, nucleosides, polysaccharides, fat-soluble vitamins and mineral elements. Tubiechong or its extract has a wide range of activities including anticoagulation and anti-thrombosis, anti-tumor, antioxidant, immune regulation, blood lipid regulation and hepatoprotection. Finally, a periodic mini-review was conducted to summarize such chemical and pharmacological profiles of Tubiechong medicine. The active peptides in Tubiechong are majorly focused in this review and introduced as one important aspect since there is much literature and huge investigative interest in it. Traditional medical use of the insect was also stressed in this review associating with its disease-eliminating actions by promoting blood circulation or eliminating tissue-swelling pains, which might play important roles in anticancer practices or investigation. In accordance with the modern pharmacological progress, Tubiechong and its extracts indeed exerted antitumor actions through multiple pathways, such as interfering with tumor biological behaviors (growth, apoptosis, invasion, metastasis and angiogenesis), and regulating host immune function. To some extent, this knowledge would provide a basis for further research and application of Tubiechong medicine.

For the removal of arsenic from marine products, iowaite was prepared and investigated to determine the optimal adsorption process of arsenic. Different chemical forms of arsenic (As(III), As(V)) with varying concentrations (0.15, 1.5, 5, 10, 15, and 20 mg/L) under various conditions including pH (3, 5, 7, 9, 11) and contact time (1, 2, 5, 10, 15, 30, 60, 120, 180 min) were exposed to iowaite. Adsorption isotherms and metal ions kinetic modeling onto the adsorbent were determined based on Langmuir, Freundlich, first- and second-order kinetic models. The adsorption onto iowaite varied depending on the conditions. The adsorption rates of standard solution, As(III) and As(V) exceeded 95% under proper conditions, while high complexity was noted with marine samples. As(III) and As(V) from Mactra veneriformis extraction all decreased when exposed to iowaite. The inclusion morphology and interconversion of organic arsenic limit adsorption. Iowaite can be efficiently used for inorganic arsenic removal from wastewater and different marine food products, which maybe other adsorbent or further performance of iowaite needs to be investigated for organic arsenic.

This study described the rheological and mucoadhesive properties of one natural water-soluble polysaccharide from Bletilla striata (BSP). The rheological characteristics of BSP in aqueous solutions and BSP mixed with other polymers were investigated under various conditions, including concentration, temperature, pH, and salt addition. Viscometric studies and ex vivo mucoadhesion tests were also conducted to examine the mucoadhesive properties of BSP. Results indicated that BSP behaved as a shear-thinning fluid at various concentrations, and its viscosity decreased at high temperatures. The viscous flow properties of the BSP mixtures changed at high pH (>5.0). Conversely, the viscosity of the BSP solutions was slightly affected by electrolytes. The viscosities of the BSP mixtures with four other commonly used polymers (sodium alginate, sodium carboxymethyl cellulose, hypromellose, and chitosan) were enhanced. The synergistic viscosity of BSP/mucin mixtures increased as BSP concentrations increased, and the maximum value was observed in the SIF medium without enzymes. The adhesive abilities of 5.0% and 10.0% BSP were almost equivalent to that of 0.5% sodium alginate, suggesting that BSP exhibited a certain mucoadhesive property, although it was weaker than that of the other commonly used mucoadhesive materials. BSP showed potential for pharmaceutical excipient applications in bioadhesive drug delivery systems.

The Quality-by-Design (QbD) approach was employed to investigate the fluid-bed coating process for the conversion of ginkgo lactone (GL) liquid nanosuspensions into dried nanosuspensions. The effects of critical process variables including inlet air temperature, inlet air capacity and atomizing air pressure were investigated. The particle size and percent yield were optimized using a full factorial design. A Box-Behnken design (BBD) was employed to generate the response surface and optimize process conditions. Multi-linear regression and one-way ANOVA were used to analyze the relationship between critical variables and responses. The results showed that all three selected variables were significant factors (p < 0.05) affecting the particle size. Higher inlet temperature, inlet air capacity or atomizing air pressure will cause an increase of particle size. In addition, the percent yield primarily depended on the inlet air temperature and inlet air capacity (p < 0.05). A higher percent yield was obtained at a higher inlet air temperature or inlet air capacity. The optimal conditions for BBD, including inlet air temperature, inlet air capacity and atomizing air pressure, were set at 40 °C, 11.6 Nm3 and 0.7 bar, respectively. Compared with the raw GLs, the optimized products presented an amorphous state and possessed much faster dissolution. The particle size, percent yield, PDI, zeta-potential and redispersibility index of the optimized products were 254.3 ± 9.8 nm, 82.36 ± 1.87%, 0.155 ± 0.02, −32.9 ± 3.8 mV and 113 ± 4.4% (n = 3), respectively. These results indicate that fluid-bed coating technology based on a QbD approach was sufficient for the solidification of nanosuspensions.

Many natural polysaccharides from bio-resources hold advantages of multi-functions, high efficiency, non-toxicity or low side effect, and have strong potentials in protection against alcoholic liver damages. This review summarized the bio-resources, chemical and structural characteristics of natural polysaccharides with potentials in inhibition against alcoholic liver damages, and also emphasized knowledge on correlations between their chemical structure and function. Approximately 95 species were confirmed in generation of hepatoprotective polysaccharides. Products as crude polysaccharides originated from 17 species were sum up despite the indetermination of their accurate structure. Additional four polysaccharides were described for their known chemical structures. Possible roles of hepatoprotective polysaccharides were provided with evidence on antioxidant promotion, lipids regulation, apoptosis inhibition and anti-inflammation, as well as confirmations in immune enhancement, iron removal and anti-fibrosis when currently treated against the alcoholic liver damages. To sum up, this overview could serve to guide development and utilization of natural hepatoprotective polysaccharides.

Great efforts have been made to identify the principle bioactive constituents of Chinese herbs and to unravel the molecular mechanisms behind their anticancer effects. Scutellaria baicalensis (Huangqin or Chinese skullcap) is a widely consumed herbal medicine and has been historically used in anticancer therapy in China and other countries. Chinese skullcap generates many active chemicals in the root and is abundant in polyphenols, which act as its anti-cancer ingredients. It contains around 53 polyphenols in total: 50 flavonoids and 3 stilbenes. The polyphenols have similar chemical structures since they are derived from similar biochemical synthetic pathways. According to the literature, as the active chemicals of the skullcap root, 18 polyphenols exhibit evident anticancer activities. They can be developed not only as novel candidates and precursors in anticancer drug screening, but also as important tools and agents in cancer pharmacology. We comprehensively elaborated the anticancer pharmacological properties of crude polyphenolic extracts and 12 other single compounds excluding the six well-known polyphenols, i.e., baicalein, baicalin, wogonin, wogonoside, chrysin and verbascoside. In this review, we also discussed the possible mechanisms of the anticancer effect of several skullcap polyphenols. Overall, this paper provides a unique path to understand the anticancer properties of Chinese skullcap as well as guidance to find novel anticancer drugs from a natural polyphenolic reservoir.

Previously, we have reported the evaluations of alginate and Bletilla striata polysaccharide (BSP) in formulation of microsphere, which is a muco-adhesive carrier and can achieve a long duration of gastric retention. The combination of Panax notoginseng (Burk.) and B. striata is a traditional Chinese herbal formula that is used to treat gastric ulcers. BSP, an effective ingredient of B. striata, possesses both medicinal and excipient functions. Panax notoginseng saponin (PNS), which can easily dissolve in water, is the main effective ingredient in P. notoginseng (Burk.) for the treatment of gastric ulcers. However, microspheres containing PNS could directly cause drug leakage, ultimately reducing the encapsulation rate. In this study, PNS was fabricated into a hydrophobic dispersion with slow-release characteristics. Subsequently, PNS was packaged into BSP/alginate microspheres to improve the encapsulation rate. The prepared PNS-loaded microspheres were round, the release characteristics aligned with the Weibull equation, and the active ingredients were released by diffusion and erosion. The developed microspheres improved the effects of PNS and synergistically exerted the pharmaceutical effects of BSP on acute gastric ulcers.

Curcumin (CUR) has gained increasing interest worldwide due to multiple biological activities. However, the therapeutic application remains limited because of its low aqueous solubility, intestinal metabolism and poor membrane permeability. In present study, an excipient-free CUR solid dispersion co-formed with piperine (PIP), the absorption enhancer involving metabolism-permeability, was successfully prepared by melting and quench cooling (co-amorphous CUR-PIP). The co-amorphous CUR-PIP exhibited superior performance in non-sink dissolution compared with crystalline and amorphous CUR, and showed physically stable at least 3 months, attributing to the strong molecular interactions between CUR and PIP as evaluated by FTIR spectra. Furthermore, the combination of PIP with CUR in the co-amorphous formulation could inhibit the glucuronidation of CUR, as exhibited in the in vitro assay of rat intestinal microsomes. The co-amorphous CUR-PIP would also exhibit higher gastrointestinal membrane permeability of CUR, as confirmed by Papp of CUR in Caco-2 model. After administration of co-amorphous CUR-PIP, the AUC of CUR significantly increased by 2.16- and 1.92-fold those in crystalline and amorphous CUR, respectively. This study demonstrates that the developed co-amorphous CUR-PIP can enhance the bioavailability of CUR by increasing its dissolution, inhibiting metabolic processes, and facilitating membrane permeability.

We investigated presence and distribution of glycosaminoglycans (GAGs) in Meretrix meretrix soft tissue by determining GAG composition in the different parts, namely, mantle edge, foot, gill, adductor muscle, and viscera. The occurrence of glycan ingredients was examined by histochemistry, whereas GAG and general polysaccharide contents in clam tissue were qualified through extraction and determination. Tissue sections stained with alcian blue or periodic acid–Schiff demonstrated the general existence of saccharides and trifling generation of GAGs in clam tissues. GAGs coexisting with glycogens appeared to be primarily produced in the mantle and foot tissues in mucus form by visualization. The GAG content of the polysaccharide extract ranged from 16.8 to 75.8 mg in 10 g of 5 dried tissue materials in comparison with total carbohydrate level in the range of 500–1760 mg, thereby indicating that GAGs were not the major components of polysaccharide extracts. GAG composition only accounted for approximately 4% of total glycan components, which consist of the determinations of amino sugar and uronic acid. The soft tissues of clam contained abundant saccharide compounds but sparse amounts of GAGs. The results will benefit the subsequent development of products made from the polysaccharide components of M. meretrix.

Phenolic acids are widely distributed in the plant kingdom and possess a broad spectrum of pharmacological activity. However, low oral bioavailability restricts their application. In this study, a high dispersed phyto- phospholipid complex with mesoporous silica containing TPGS 1000 (TPC-SD) was fabricated using Tanshinol (Tan) as model drug. Phospholipid complex (PC) was employed to improve the n-octanol/water partition coefficient (log P) and apparent permeability coefficients (Papp) of Tan. Mesoporous silica was used to compensate for the negative effects of phospholipid on drug’s dispersion and dissolution owing to its viscosity and poor water-solubility. TPGS 1000, a P-gp inhibitor, was used to block the efflux of Tan. Log P tests showed that the lipophilicity of Tan was significantly enhanced by Tanshinol phospholipid complex (TPC) formation. In vitro dissolution results showed that the cumulative dissolution percentage of Tan from TPC-SD was 4.33- fold of that from TPC in 120 min A Caco-2 permeability test confirmed that Papp (AP-BL) of TPC and TPC-SD increased approximately 2.22- and 3.53- fold compared to those of unformulated Tan, respectively (p

Mactra veneriformis has been used as seafood and traditional Chinese medicine for thousands of years in China. In the present study, hydrolysate was prepared from waste proteins of M. veneriformis by trypsin treatment. The protective effect of hydrolysate on the defense system against oxidative stress was investigated by estimating the superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in normal mice. The antioxidant activity of hydrolysate was investigated in D-galactose-induced aging mice by estimating the SOD and glutathione peroxidases (GSH-px) activity and MDA level. Amino acid composition and molecular weight distribution were also determined. These investigations suggest that hydrolysate derived from by-products of M. veneriformis possess antioxidant activity and may be attributed to elevation of the activity of antioxidase and enhanced antioxidant defenses.

Analysis of peptide components of protein hydrolysates is often difficult due to the lack of suitable analytical methods. In the present study, an UHPLC-Q-TOF MS/MS method was developed and used to identify peptides derived from the protein hydrolysate of Mactra veneriformis. The peptide sequences were deduced by de novo sequencing based on MS/MS fragmentation data. A total of 21 peptides, four nucleobases, and one nucleoside were identified from the hydrolysate using this method. These peptides were chemically synthesised and showed antioxidant activity in radical scavenging assays. This method is suitable for quick, sensitive, and accurate analysis of complex protein hydrolysates.

Background: Mactra veneriformis, a typical marine bivalve mollusk, delicious sea food while low cost, is ubiquitous and abundant in Chinese coastal areas, especially in the coastal shoals of Jiangsu province. To our knowledge, previously reported analytical methods can not meet a set of quality control. Objective: For the simultaneous determination of eight components (uridine, inosine, guanosine, thymidine, adenosine, xanthine, thymine and hypoxanthine) in M. veneriformis, a high performance liquid chromatography with UV detector method was established. Materials and Methods: To develop the method, a reverse phase column, BioBasic-C 18 (5 μm, 4.6 mm × 250 mm) was used. The mobile phase consisted of methanol and water using a gradient elution. The UV wavelength was set at 245 nm. The analysis conditions including extraction methods, extraction solvents, and HPLC parameters were optimized systematically for achieving good separation. Linearity, accuracy, repeatability and detection limit was revealed and showed good performance. Results: The optimized HPLC method was successfully applied for the qualititation of 5 nucleosides namely, uridine, inosine, guanosine, thymidine, adenosine and 3 nucleobases namely, xanthine, thymine, hypoxanthine in M. veneriformis. Conclusion: A method with less time-consuming, more sensitive, and more precise was developed for the quantitative determination of nucleosides and nucleobases in M. veneriformis extractions. The established method might apply as an alternative approach for the quality assessment of M. veneriformis.

Mactra veneriformis has been used as sea food and traditional Chinese medicine (TCM) for thousands of years in China. In the present study, a high performance liquid chromatograph coupled with photodiode array detector and electrospray ionisation-mass spectrometer (HPLC-DAD-ESI-MS) method was established for detection of the nucleosides and nucleobases in M. veneriformis from four aquaticultural area of Jiangsu during different harvest time of one year. The validated method was successfully applied to identifying 10 nucleosides and nucleobases in 48 M. veneriformis samples. Quantitative analysis showed that nucleosides and nucleobases are rich in all M. veneriformis samples. However, their contents vary in different areas and harvest times. Principal component analysis (PCA) was used to classify the 48 samples based on the contents of the nucleosides and nucleobases. As a result, the samples could be mainly clustered into four groups, which was similar as aquaticultural areas classification. Based on the results, present method might be applicable for the quality control of M. veneriformis, or even other marine shellfish aquiculture and their products, and the quality of M. veneriformis might be more related with aquaticultural areas.

To prepare calcium-binding peptides, the flesh residue of Mactra Veneriformis was subjected to enzymatic hydrolysis. By comparing the capability of combining calcium of the hydrolyzates, pepsin was confirmed to be the most suitable enzyme for hydrolyzing the flesh residue to release calcium-binding peptides among the seven tested proteases. The pepsin hydrolyzate (PHM) was divided into three fractions according to the molecule weight of its composition, which ranged from 0.5 to 15 kDa. The low-molecule-weight fraction named PHM-3 had the highest capability in combining calcium. The peptides existing in the PHM-3 fraction consisted of higher contents of Glu, Ala and Leu, and could produce one type of calcium-peptide complex by powerfully chelating calcium ions. PHM-3 products could effectively increase calcium absorption and retention while they decreased the calcium excretion in animal tests. Additionally, symptoms caused by low calcium bioavailability in ovariectomized rats, such as bone mineral density reduction and mechanical strength loss could be significantly ameliorated by the hydrolytic products addition in diet.

Total macromolecule extract was obtained from the soft body of Mactra veneriformis by the coupling techniques of decoction and alcohol precipitation. The extract was deproteinized with an ion exchange column, and resulted in the purifying of the crude polysaccharide fraction. It was found by chemical analysis that the crude polysaccharide part is composed of abundant polysaccharides (> 95%) and few proteins (< 1%). Furthermore, only one type of monosaccharide, glucose, was detected from its hydrolytes by thin-layer chromatography, indicating that the polysaccharides might be analogs of glucosan. The anti-hyperglycemia effects of the crude polysaccharide part were preliminarily investigated using several pharmacological methods in normal and diabetic mice. Animal experimental results showed that the crude polysaccharide fraction exhibited proper glycemia inhibition activity, and 300 mg/kg-weight dose has the optimal effect among all the studied doses. It is concluded that the crude polysaccharide fraction can be explored as a novel health product that possesses potential as an anti-hyperglycemic agent.

Aqueous (ET1) and alcoholic (ET2) extracts from Mactra veneriformis were studied for their antioxidant potentials using various in vitro assays. The ET2 was fractioned into four parts according to the polarity of the extractive medium, viz. ET2-p (petroleum ether), ET2-e (ethyl acetate), ET2-n (n-butanol) and ET2-w (water). Among the four fractions, ET2-w showed the strongest reducing power, and highest 2,2 diphenyl-1-picrylhydrazyl (DPPH) scavenging and metal chelating activities, while the ET2-p possessed higher hydroxyl radical scavenging activities. It was found that ET2-w had large amounts of free amino acids and oligosaccharides, while ET2-p contained a large amount of unsaturated fatty acids. We conclude that amino acids, oligosaccharides and unsaturated fatty acids all contribute to the antioxidant activity of M. veneriformis. In order to elucidate the above, antioxidative components involved in the antioxidant activities were also detected. It was found that amino acids and carbohydrates were the major components of ET2-w. The amino acids were Tau (0.26%), Tyr (0.38%), Met (0.31%), Cys (0.38%), Arg (1.79%) and so on, while carbohydrates were oligosaccharides that were composed of disaccharides and trisaccharides. The unsaturated fatty acids were the major components of ET2-p, which contained a high amount of docosahexaenoic acid (9.03%) and eicosapentaenoic acid (18.49%).

Marine ecosystems can be considered as a rather unexplored source of drugs as well as a surprising reservoir ofbioactive oligosaccharide. Marine oligosaccharides could be obtained by hydrolysis of polysaccharide existing ina variety of biomass sources or synthesized by simple oligosaccharides. In recent years, marine oligosaccharideswhich degraded by polysaccharides are attracting increasing interest in developing potential drugs for chronicdiseases. Significant efforts have been made to find and confirm their bioactivity such as anti-tumor, antimicrobial,antioxidant, anti-inflammatory and so on. In this review, the mechanisms of bio-function eliciting kinds ofapplications of different marine oligosaccharides are summarized.