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Highlights: [•] The major product Rd possesses higher bioactivities and bioavailability than Rb1. [•] This study can solve the waste problem of ginseng extraction residue. [•] A new functional food ingredient was developed. [•] It is the first report on applying lingzhi (G. lucidum) to transform ginsenosides from AmR. [Copyright &y& Elsevier]

Abstract: The effect of different drying methods on steroidal saponins, furostanol and spirostanol glycosides, in Dioscorea pseudojaponica Yamamoto, were studied. The yams were either steam-blanched or not blanched before drying. Results showed that solar and shaded drying without prior blanching would cause significant changes of yam saponins; hot air drying caused slight variation, and other drying methods showed almost no change. A similar phenomenon was observed in a model system containing crude yam saponin extract; it indicated that higher temperature and light exposure had very little effect on the stability of yam saponins during drying. On the other hand, the endogenous glucosidase in yam might play an important role in altering the saponin structures during drying. This was confirmed by a model experiment; a crude furostanol glycoside 26-O-β-glucosidase prepared from yam was shown to remove the glucose at position C-26 of the furostanol glycoside structure and change it to the respective spirostanol glycoside. [Copyright &y& Elsevier]

Abstract: Starch was extracted from the tubers of two cocoyam (Xanthosoma sagittifolium) cultivars (KCX01 and KCX02) planted in three different seasons (summer, winter and spring). Physicochemical properties of the starch were determined in order to investigate the seasonal effect on cocoyam starch. Cocoyam tubers planted in the summer showed higher contents of total starch than tubers planted in other seasons. Starches from both cultivars of cocoyam tubers planted in the summer season had significantly (p<0.05) higher average granule sizes, higher contents of amylose, higher ratios of short-to-long chains of amylopectin, and lower values of the average degree of polymerization (DP) of the chain length distribution profiles. The distinct properties of the fine structure of cocoyam starch from tubers planted in summer season were associated with lower values of onset and peak temperatures and enthalpies of gelatinization. [Copyright &y& Elsevier]

• Composite antioxidants were used to improve oxidative stability of DHA algae oil. • Phytic acid was used in combination with other antioxidants. • Shelf life were predicted by accelerated shelf life testing with Arrhenius model. • Optimum composite antioxidant extended 3.80-fold shelf life of DHA algae oil. • Loss of PUFA was significantly reduced by the composite antioxidants. Based on various antioxidant mechanisms, four kinds of antioxidants including ascorbyl palmitate (AP), vitamin E (VE), phytic acid (PA) and one of the polyphenols (antioxidant of bamboo leaves, tea polyphenol palmitate or tea polyphenols (TP)) were used in combination to improve oxidative stability of docosahexaenoic acid (DHA) algae oil. To achieve the best effect, the formulations and mixture ratios of the antioxidant combinations were optimized. The effects were monitored by peroxide value, thiobarbituric acid-reactive substances, acid value, free radicals, Rancimat induction time and fatty acid composition of DHA algae oil undergoing accelerated storage. Finally, the DHA algae oil containing 80 mg/kg AP, 80 mg/kg VE, 40 mg/kg PA and 80 mg/kg TP had the highest oxidative stability. Furthermore, the shelf life of DHA algae oil containing the optimum composite antioxidant was predicted by using accelerated shelf life testing coupled with Arrhenius model, which was 3.80-fold longer than the control sample. [ABSTRACT FROM AUTHOR]

Whelk has been exploited commercially as a delicacy for a long time. Although previous studies have suggested that whelk might serve as a potential rich source of long chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA) enriched phospholipid (PL), the molecular species profile of the PL have not been reported yet. In this study, more than 220 molecular species of glycerophospholipid (GP) belonging to eight classes including glycerophosphocholine, glycerophosphoethanolamine, glycerophosphoserine, glycerophosphoinositol, lysoglycerophosphocholine, lysoglycerophosphoethanolamine, lysoglycerophosphoserine and lysoglycerophosphoinositol in three species of edible whelks ( Buccinium yokomaruae , Neptunea arthritica cumingi Cosse and Volutharpa ampullaceal ) were identified for the first time by using direct infusion tandem mass spectrometric method. Most of the predominant GP molecular species contained n-3 LC-PUFA, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Meanwhile, the whelk lipids contained a high proportion of PL (32.92–55.55% of total lipids) and PUFA (30.45–41.42% of total FA). Among PL, phosphatidylcholine (44.18–65.49 mol%) was dominant. [ABSTRACT FROM AUTHOR]

Sea urchin gonad has been regarded as a “healthy” food. Although previous studies have suggested that sea urchin gonad might serve as a potential rich source of long chain omega-3 polyunsaturated fatty acids (n-3 LC-PUFA) enriched phospholipid (PL), the molecular species profile of its PL has rarely been reported. In this study, about 200 molecular species of glycerophospholipid (GP), including glycerophosphocholine, glycerophosphoethanolamine, glycerophosphoserine, glycerophosphoinositol, lysoglycerophosphocholine and lysoglycerophosphoethanolamine, in gonads from three species of sea urchin ( Glyptocidaris crenularis , Strongylocentrotus intermedius and Strongylocentrotus nudus ) were characterized using tandem mass spectrometry. Most of the predominant GP molecular species contained PUFA, especially eicosapentaenoic acid (EPA). Meanwhile, the sea urchin lipids contained a high proportion of PL (39.45–50.30% of total lipids) and PUFA (34.47–46.56% of total FA). Among PL, phosphatidylcholine (67.88–72.58 mol%) was dominant. Considering the high level of PUFA enriched GP, sea urchin gonads provide great potential as health-promoting food for human consumption. [ABSTRACT FROM AUTHOR]

Highlights • Bioconversion of mogrosides in yeast and in lactic acid bacteria. • Various microbes produce different mogroside bioconversion patterns. • DbExg1 and ScExg1 function differently with respect to mogroside hydrolysis. • D. bruxellensis is unique to bioconvert the mogroside V into siamenoside I. Abstract In response to growing concerns about the consumption of artificial sweeteners, the demand for natural sweeteners has recently increased. Mogroside V is a common natural sweetener extracted from the fruit of Siraitia grosvenorii , but its taste should be improved for marketability. Here, we screened various microbes for the ability to perform selective hydrolysis of glycosidic bonds in mogroside V, converting it to siamenoside I, which has a higher sweetening power and better taste than other mogrosides. Dekkera bruxellensis showed the most promising results in the screen, and the Exg1 gene (coding for a β -glucosidase) of D. bruxellensis was cloned and purified. We then used HPLC-MS/MS to assess the β -glucosidase activity of purified enzymes on p -nitrophenyl β- glucoside and mogroside V. The results demonstrated that D. bruxellensis had a unique enzyme that can selectively hydrolyze mogrol glycosides and promote the conversion of the natural sweetener mogroside V to siamenoside I. [ABSTRACT FROM AUTHOR]

Different classes of lipids and phospholipids (PL) as well as fatty acid (FA) compositions, and glycerophospholipid (GP) molecular species in edible parts (adductor muscles) and by-products (gonads and mantles) of scallops Patinopecten yessoensis and Chlamys farreri were characterized. The lipids contained high levels of polyunsaturated FA (PUFA) (20.44–58.81% of total FAs) and PL (54.99–78.26% of total lipids). Among PL, phosphatidylcholine (41.39–51.86 mol%) was dominant. More than 230 GP species belonging to glycerophosphocholine, glycerophosphoethanolamine, glycerophosphoserine, glycerophosphoinositol, lysoglycerophosphocholine, lysoglycerophosphoethanolamine and lysoglycerophosphoinositol were characterized. Individual GP molecular species in different body parts of scallops were also partially quantified. Most of the dominant GP species contained PUFA, especially eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). Considering the high level of PUFA enriched GP, edible parts and by-products (gonads and mantles) of scallops Patinopecten yessoensis and Chlamys farreri provide great potential as health-promoting food for human consumption. [ABSTRACT FROM AUTHOR]

The autolysis of sea cucumber body wall is caused by endogenous proteolysis of its structural elements. However, changes in collagen fibrils, collagen fibres and microfibrils, the major structural elements in sea cucumber body wall during autolysis are less clear. Autolysis of sea cucumber ( S. japonicus ) was induced by cutting the body wall, and the structural and biochemical changes in its dermis were investigated using electron microscopy, differential scanning calorimetry, infrared spectroscopy, electrophoresis, and chemical analysis. During autolysis, both collagen fibres and microfibrils gradually degraded. In contrast, damage to microfibrils was more pronounced. Upon massive autolysis, collagen fibres disaggregated into collagen fibril bundles and individual fibrils due to the fracture of interfibrillar bridges. Meanwhile, excessive unfolding of collagen fibrils occurred. However, there was only slight damage to collagen monomers. Therefore, structural damage in collagen fibres, collagen fibrils and microfibrils rather than monomeric collagen accounts for autolysis of S. japonicus dermis. [ABSTRACT FROM AUTHOR]

[Display omitted] • An improved PGC-LC-Orbitap MS/MS method revealed the diversity of GOS with DP2-DP6. • The system separated and identified 58 linear and 10 branched GOS. • Fifteen major group components with DP2-DP5 comprised over 65% of total GOS content. • Non-reducing GOS components with DP2-DP6 comprised 2.8–7.6% of total GOS content. • The major structural diversity occurred in DP3-DP5 GOS. Galacto-oligosaccharides (GOS) are important prebiotic supplements for commercial nutraceutical food. The prebiotic efficacy of functional GOS is dependent on their chemical profile. Screening potential markers aids specifications and quality control of GOS materials. However, profiling analysis of GOS with a degree of polymerization (DP) ≥ 4 is still challenging. This study presents a porous graphitic carbon liquid chromatography-orbitrap tandem mass spectrometry-based method that characterized 58 linear and 10 branched GOS and detected 59 non-reducing GOS from DP2 to DP6. The results indicated that 15 major group components with DP2-DP5 accounted for more than 65% of total GOS content in GOS samples, while non-reducing GOS components accounted for only 2.8–7.6%. Substantial variations in components occurred in samples from different batches and sources. Structural and constitutive diversity were dominated by DP3-DP5. This method can help control the quality of GOS products and be used to investigate the structural and prebiotic-efficacy relationships. [ABSTRACT FROM AUTHOR]

• KCl interacts with konjac glucomannan to form the structure. • Konjac glucomannan chains break and partially deacetylate under alternating current. • Alternating current induces the formation of konjac glucomannan-KCl electrogel. • Konjac glucomannan-KCl electrogel possesses an ununiform porosity structure. • Viscoelastic moduli of the gels depend on KCl and konjac glucomannan concentration, voltage and electric processing time. Konjac glucomannan (KGM) electrogels were successfully prepared under alternating current (AC) in the presence of potassium chloride (KCl). The structure of the gels was studied using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and scanning electron microscopy (SEM). A single-factor experiment was performed to optimize the preparation of the gels. Our results showed that KGM was degraded under AC and partially deacetylated. KGM and KCl formed the structure , and electrogels with porous structures retained some acetyl groups. Furthermore, as the KCl concentrations, voltages, time, and KGM concentrations increased, the viscoelastic moduli of the gels increased; the moduli decreased when the KCl concentrations, voltages, and time exceeded critical values. [ABSTRACT FROM AUTHOR]