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The present study shows the purification of a main oligosaccharide fraction (MLO 1-2) from the enzymatic hydrolysate of mulberry leaf polysaccharides by DEAE-52 cellulose and gel column chromatography. The physicochemical properties of MLO 1-2 were characterized. The structure of MLO 1-2 was obtained as follows: α-(2-OAc)-Man

Mulberry possesses many biological characteristics, such as reduce blood sugar and antioxidant properties, but whether mulberry galacto-oligosaccharide (MGO) can impact the characteristics of the gut microbiota is not yet clear. The objective of this work was to investigate the protective effects of MGO in type 2 diabetic (T2D) mice. The analysis of typical diabetic symptoms and serum status showed that oral MGO alleviated hyperglycemia, insulin resistance and oxidative stress in diabetic mice. These changes were caused by up-regulating the expression of key proteins in the PI3K/Akt pathway, involved in the control of liver glycolysis and gluconeogenesis, and liver glucose metabolism having a positive hypoglycemic effect. Additionally, the gut microbiota indicated that MGO treatment could positively modulate the microbiome composition to decrease the blood glucose in diabetic mice by promoting the growth of Prevotellaceae and Lactobacillus, whereas decreasing the abundance of Lachnospiraceae.

Mulberry has significant hypoglycemic effect and can be used as an auxiliary food for people with type 2 diabetes. However, it is rich in carbohydrate and cannot be consumed directly by diabetic patients. In the study, we fermented the mulberry to reduce the content of glucose and fructose, and added the soybean to reduce the loss of probiotics during fermentation and then determined its hypoglycemic effect. We induced type 2 diabetes mellitus (T2DM) mice by streptozotocin and measured its blood glucose, serum biochemistry, hepatic and pancreatic histopathology, and the diversity of the gut microbiota. After 5 weeks of oral DFMS administration, the glucose tolerance was improved significantly in T2DM mice. Furthermore, there were also significant increases in superoxide dismutase activity and glutathione concentration, and marked reductions in the concentrations of malondialdehyde and free fatty acids. Moreover, DFMS also prevented histopathological changes and the increases in the activities of alanine transaminase and aspartate transaminase. DFMS treatment also markedly increased the richness of the gut microbial community. The abundance of Bacteroidetes was increased, and those of Proteobacteria, Escherichia‐Shigella, and Lactobacillus were reduced. In summary, DFMS has a clear hypoglycemic effect in mice with T2DM., In this passage, we produced a freeze‐dried preparation of fermented mulberry mixed with soybean (DFMS) to verify the protection of probiotic of soybean and determined its effect on hyperglycemia in diabetic mice. Our findings indicated that DFMS had an obvious hypoglycemic effect on T2DM mice, which is possibly related to its low carbohydrate content and the high levels of 1‐deoxyricogen and probiotic.

Background Historically, mulberry has been effectively used as a traditional medicine in Asia for the treatment of various infectious and internal diseases. It is a rich source of bioactive compounds that can promote human health. However, to date, it has not been officially or scientifically recognized because of a lack of accepted and standardized methodology for its evaluation. Numerous studies have been conducted by applying modern biotechnological tools to explore the relationship between the active ingredients in mulberry and their biological activities to solve ambiguities in their mechanism of action, opening a new horizon in traditional Chinese medicine with the potential for modernization in the near future. Scope and approach This paper presents a concise overview on mulberry by examining its major bioactive components, including anthocyanins, polysaccharides, phenols, alkaloids and flavonoids. Recent technical advances are discussed for extraction (solid-liquid extraction, pressurized liquid extraction, supercritical-fluid extraction, microwave-assisted extraction, ultrasonic assisted extraction, enzymatic assisted extraction, solid-phase extraction) and separation (macroporous resins adsorption, silica gel chromatography, ion exchange chromatography, gel filtration chromatography, preparative liquid chromatography, countercurrent chromatography). Key findings and conclusions The mystery behind mulberry lies in various bioactivities that have been explored by modern technologies. Studies employing efficient, systematic, and practical protocols for sample preparation and isolation integrated with various analytical systems have been applied to discover, separate, and identify analytes in natural plants especially traditional Chinese medicines and to explore the scientific principles that will benefit the standardization and modernization of natural product research.

Silkworm pupae are a source of edible lipid with a high content of unsaturated fatty acids (UFAs) (70% of total lipid content) and are becoming a focus of pharmaceutical and dietary research in the functional oil field. To study the nutritional value of different silkworm strains, principal component analysis (PCA) was used to establish a mathematical model and cluster analysis on silkworm pupae lipid (SPL) in 90 strains based on Z-score. Single-factor correlation analysis indicated that the PUFAs content was significantly positively correlated with the α-linolenic acid (ALA) (ρ = 0.98) and negatively correlated with the oleic acid (OA) (ρ =− 0.73) contents, and comprehensive of principal components mathematical model (PC = 0.148ZX1 + 0.002ZX2 − 0.197ZX3 − 0.338ZX4 + 0.220ZX5 + 0.304ZX6 + 0.314ZX7, ZXi is the standard score (Z-score) of X1, which was calculated as follow: Z X i = ( X i − X − )/S, where X1: palmitic acid, X2: palmitoleic acid, X3: stearic acid, X4: OA, X5: linoleic acid, X6: ALA, X7: PUFAs. X − is the arithmetic mean content of variable i, and S is the standard deviation of variable i for all samples included in the analysis.) showed the amount of ALA and PUFAs were the key factors determining the nutritional value of the pupae lipid. Cluster analysis on the composite scores calculated by the model of the principal component divided the 90 strains into three groups. A cluster of 6 strains (XHR, XIFF, ZX, YT, YO and BTN) with the best nutritional value was characterized by high contents of ALA and PUFAs and a low content of oleic acid.

The effects of alkali dissociation on the molecular conformation and immunomodulatory activity of longan pulp polysaccharide (LPI) were investigated to explore their possible relationship. The molecular conformations of LPI and its degraded derivatives (LPI1 and LPI2) were examined by size exclusion chromatography combined with multi-angle laser light scattering (SEC-MALLS), Congo red test and atomic force microscopy (AFM). The results confirmed the transformation of LPI from compact sphere-like conformation to slightly dissociated sphere-like conformation (LPI1) or single-helix chain (LPI2). Compared with the control, splenocyte proliferation and NK cell cytotoxicity were significantly enhanced by LPI1 and LPI2 (P 0.05). All the polysaccharides could significantly enhance macrophage phagocytosis at 100 or 200 μg/mL (P

Natural antioxidants such as polysaccharides with strong antioxidant activities are used to protect against oxidative damage, yet little is known so far about the antioxidant effects of litchi fruit polysaccharides. In the present study, four different polysaccharide-enriched fractions were isolated from litchi pulp tissue and partially purified by a stepwise method of ethyl alcohol (EtOH) precipitation. Their chemical and physical characteristics were determined by chemical methods, gas chromatography and IR spectrophotometry. Antioxidant activities of these fractions were investigated using various in vitro assay systems. These four polysaccharide-enriched fractions exhibited a dose-dependent free radical scavenging activity as shown by their DPPH radical, superoxide anion and hydroxyl radical inhibition, chelating ability and reducing power. Among the different fractions, LFP-III showed the strongest scavenging activity against DPPH radical, superoxide and hydroxyl radicals and chelating ability. These findings suggest litchi polysaccharides from pulp tissue have potential as functional foods with enhanced antioxidant activity.

Background: In this study, ultrasonic-microwave-assisted extraction (UMAE) was first applied to extract polysaccharides from the leaves of mulberry (PLM). The optimal conditions for polysaccharides extraction were determined by response surface methodology (RSM) along with central composite design (CCD) based on the singlefactor experiments. Extraction temperature (°C), extraction time (s), pH value, and ratio of water to raw material were investigated. Also, the antioxidant activities of PLM with UMAE were evaluated. Results: According to statistical analysis, extraction temperature and pH value significantly affected extraction yield. The central composite design (CCD) showed that polynomial regression models were in good agreement with the experimental results with the coefficients of determination of 0.9263 for PLM. The optimal conditions were extraction temperature 76°C, extraction time 807 s, pH value 6.16 and the ratio of water to raw material 40:1, and the maximal yield of PLM was 10.29 ± 0.41(%). Meanwhile, DPPH radical-scavenging at EC50 values of PLM was found to be 128.3 μg/ml. Conclusion: Under the optimal conditions, the experimental values agreed with value predicted by the model. The results suggested that UMAE could be used for the extraction of PLM, and the polysaccharides from mulberry leaves have significant antioxidant activities, which can be used as a source of potential antioxidant.

The application of microbial transformation technique makes it possible to provide commercial mulberry foods with stable quality as well as keeping its original nutrition. Food-grade yeasts, lactic acidbacteria and acetic acid bacteria have been used in mulberry foods fermentation in recent years. With considerable research work on medicinal and nutritious value of mulberry around the world, mulberry has been commercially processed into red wine, yoghurt and vinegar which are welcomed by more and more consumers all over the world.

As antibiotic drug resistance has become one of the most serious threats to global public health, there is a pressing need to look for new effective therapeutic drugs. Flavonoids are a large class of chemicals widely exist in plants, and have such effects as direct antibiotics, synergistic antibiotics and inhibition of bacterial activity. In this article, we made a summary for the advance in studies on the antibacterial effects of flavonoids and their mechanism.

Sericulture is a traditional and well-known industry with a 5000-year history in China. ‘Byproducts of sericulture’ which do not directly generate economic benefits, are typically wasted: e.g., fruits, stems, surplus leaves from silkworm feeding, pupae and moths. However, the above resource is of great potential nutritional and medicinal value and deserves systematic and profound study.

Silkworms are drawing international scientific attention owing to their significant hypoglycemic activity, attributed to 1-deoxynojirimycin (DNJ), which they obtain from eating mulberry leaves. DNJ content in silkworms varies significantly during its life cycle as a holometabolic insect. The effect of metamorphosis and molting on DNJ accumulation remains unclear, however. More knowledge is needed about DNJ dynamics during the silkworm life cycle given their potential use as a functional food with hypoglycemic effect. This paper aims to elucidate the DNJ dynamics of silkworms over their life cycle. We propose the best physiological stage for silkworm harvesting in consideration of DNJ production. The effect of metamorphosis and molting on DNJ accumulation is also discussed. Samples from key physiological stages of silkworms were collected and the DNJ content analyzed by reverse-phase high-performance liquid chromatography (RP-HPLC). We observed fluctuations in DNJ levels depending on the physiological stage of the silkworm. A higher level of DNJ was found in the molted larvae than the molting ones. The highest DNJ level was detected in the molted larvae of instar III (5.46 mg/g) in terms of bodyweight, while a silkworm from Day 3 of instar V possesses the highest level of DNJ (1512.46 μg per silkworm). These results imply that natural physiological changes in the silkworm, including molt and metamorphosis, affect DNJ accumulation significantly. The period from Day 3 to Day 4 of the 5th instar is considered the best time for silkworm harvesting given both DNJ concentration and silkworm biomass.

The antioxidant activity and stability of peptides from male silkmoth hydrolysates (MSH) was studied as antioxidant ingredients in potential food applications. MSH were isolated into five fractions: MSH-I (MW > 30 kDa), MSH-II (10–30 kDa), MSH-III (5–10 kDa), MSH-IV (3–5 kDa), and MSH-V (

An aqueous extract of polysaccharides from longan pulp was chromatographed on a DEAE anion-exchange column to yield four fractions (LPI-IV). Immunomodulatory activities of these polysaccharides were also evaluated in vitro. The purified products, neutral polysaccharide LPI, polysaccharide-protein complex LPII and acidic polysaccharides LPIII and LPIV, exhibited conspicuous differences in their monosaccharide composition, molecular mass and glycosidic linkages. Except for LPI, the other three significantly stimulated lymphocyte proliferation in the dose range of 100-400μg/mL compared with the normal control (P0.05), and might electively stimulate B cells, but not T cells. Furthermore, their stimulations on normal/lipopolysaccharide-induced proliferation and depressions on concanavalin A-induced proliferation could be ordered as LPIIILPIVLPIILPI. All the fractions had the optimal dose of 100μg/mL on enhancing macrophage phagocytosis. Among them, LPII had the considerable yield and activity for exploiting as a potential immunoadjuvant.

Two new 2-phenylbenzofuran derivatives, atrofuran A (1) and atrofuran B (2), along with five known compounds, were isolated from the root bark of Morus atropurpurea. The structures of the new compounds were determined on the basis of extensive NMR spectroscopic and HR-ESI-MS analyses.