Mulberry leaf flavonoids activate BAT and induce browning of WAT to improve type 2 diabetes via regulating the AMPK/SIRT1/PGC-1α signaling pathway / 中国天然药物

Mulberry (Morus alba L.) leaf is a well-established traditional Chinese botanical and culinary resource. It has found widespread application in the management of diabetes. The bioactive constituents of mulberry leaf, specifically mulberry leaf flavonoids (MLFs), exhibit pronounced potential in the amelioration of type 2 diabetes (T2D). This potential is attributed to their ability to safeguard pancreatic β cells, enhance insulin resistance, and inhibit α-glucosidase activity. Our antecedent research findings underscore the substantial therapeutic efficacy of MLFs in treating T2D. However, the precise mechanistic underpinnings of MLF's anti-T2D effects remain the subject of inquiry. Activation of brown/beige adipocytes is a novel and promising strategy for T2D treatment. In the present study, our primary objective was to elucidate the impact of MLFs on adipose tissue browning in db/db mice and 3T3-L1 cells and elucidate its underlying mechanism. The results manifested that MLFs reduced body weight and food intake, alleviated hepatic steatosis, improved insulin sensitivity, and increased lipolysis and thermogenesis in db/db mice. Moreover, MLFs activated brown adipose tissue (BAT) and induced the browning of inguinal white adipose tissue (IWAT) and 3T3-L1 adipocytes by increasing the expressions of brown adipocyte marker genes and proteins such as uncoupling protein 1 (UCP1) and beige adipocyte marker genes such as transmembrane protein 26 (Tmem26), thereby promoting mitochondrial biogenesis. Mechanistically, MLFs facilitated the activation of BAT and the induction of WAT browning to ameliorate T2D primarily through the activation of AMP-activated protein kinase (AMPK)/sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α) signaling pathway. These findings highlight the unique capacity of MLF to counteract T2D by enhancing BAT activation and inducing browning of IWAT, thereby ameliorating glucose and lipid metabolism disorders. As such, MLFs emerge as a prospective and innovative browning agent for the treatment of T2D.

A Preliminary Study for the Suppressive Effect of Mulberry Leaf Powder-containing Foods on the Postprandial Blood Glucose Level / 日本補完代替医療学会誌

A crossover study was conducted to evaluate suppressive effect of a commercially available green juice (Katuna-Aojiru;Egao Co., Ltd.) containing mulberry leaf powder as the main ingredient on postprandial hyperglycemia. The blood glucose and iAUC (0-120min) values after loading cooked white rice were significantly lower with the consumption of Katuna-Aojiru than with the consumption of water. Katuna-Aojiru is effective in controlling postprandial blood glucose.

Research progress in mulberry leaf polysaccharide in treating diabetic nephropathy / 中国药理学与毒理学杂志

Diabetic nephropathy (DN) is one of the most common complications of diabetes. It is an important cause of diabetes disability and death. DN is a systemic metabolic syndrome. In its pathogenesis, the interaction of various cell activities and a large number of cytokine biological activities, the activation of signal pathways and so on are involved in the development of DN. At present, the clinical treatment of DN is mainly Western medicine, but it has limitations such as strong toxicity, high side effects and poor compliance. Therefore, the discovery of natural anti-DN substances has also become an important means to treat DN. Mulberry leaves are the dry leaves of Morus alba L. It is not only a tradi?tional Chinese medicine, but also a dual-purpose medicinal material for medicine and food. It has the effects of dispelling wind and clearing heat, cooling blood and brightening eyes, tonifying and so on. Mulberry leaf polysaccharide (MLP) is a kind of high molecular compound in mulberry leaves. It has many pharmacological effects, such as hypoglycemic, antiox?idant, anti-stress, anti-virus and so on. Therefore, the pharmacological effects of mulberry leaf polysaccharides on dia?betic nephropathy are reviewed in this paper, so as to provide references for further research and application. The patho?genesis of DN is complex, and the mechanism of renal injury has not been completely clarified. The current studies believe that DN is closely related to heredity, abnormal glucose metabolism, abnormal lipid metabolism, microcirculation disorder, cytokine action, oxidative stress and so on. Relevant studies show that the pharmacological effects of mulberry leaf polysaccharide in the prevention and treatment of DN mainly include: ① Effect on transforming factor-β1 (TGF-β1):TGF-β1 has become an important cytokine involved in the formation of renal fibrosis by regulating cell proliferation and differentiation and the production of extracellular matrix (ECM). MLP can significantly inhibit TGF-β1 protein, and then inhibit the synthesis of extracellular matrix by renal interstitial fibroblasts and inhibit the realization of fibrosis.②Effect on insulin receptor substrate (IRS-1): IRS-1 is an important signal molecule at the beginning of IR signal transduction. The decrease of IRS-1 gene expression or the decrease of expression can affect the effective transmission of IR signal and lead to the development and deterioration of diabetes. MPL can significantly increase the expression of IRS-1 mRNA in liver tissue of DN rats, so as to prevent and treat DN. ③ Effect on the expression of resistin protein in adipose tis?sue. Resistin is a secretory polypeptide derived from adipose tissue and is specifically expressed in white adipose tissue and is closely related to type 2 diabetes mellitus (T2DM). Experimental studies show that MLP can effectively reduce the expression of resistin protein in white adipose tissue of T2DM rats, indicating that MLP may reduce the level of IR by inhibiting the expression of resistin in adipose tissue, thereby reducing the insulin resistance state of T2DM rats, so as to achieve the goal of treating diabetes.④Effect on adiponectin receptor 1 (AdipoR1):adiponectin can improve insulin resistance, reduce blood glucose and lipid. AdipoR1 is mainly expressed in skeletal muscle and kidney. Studies have shown that AdipoR1 is closely related to the occurrence and development of DN. The results showed that MLP could reduce the blood glucose and blood lipid level and up regulate the expression of AdipoR1 mRNA in DN rats, suggesting that MLP may delay the occurrence and development of DN. This article reviewed the pharmacological effects of mulberry leaf polysaccharides on diabetic nephropathy, and provided a useful basis for further development and utilization of mul?berry leaf polysaccharides in the treatment of DN.

Effects of the mulberry leaf extract on depression-like behavior in mice / 国际药学研究杂志

Objective: To investigate the antidepressant effect and mechanism of the extract of mulberry leaf(EML). Methods: Male BALB/c mice were randomly assigned to receive EML(100, 200 and 400 mg/kg)or vehicle for 7 days or single administration by intragastric(ig)route. The effect of EML on spontaneous activity in mice was evaluated using the open field test. The anti-depressant activity of EML was evaluated using the tail suspension test and forced swimming test. After single ig administration of EML (100, 200 and 400 mg/kg), the effects of EML on the function central monoaminergic nervous system were evaluated using the 5-hydroxy-L-tryptophan(5-HTP)induced head-twitch test, yohimbine toxicity potentiation test and reserpine test in mice. Results: In the behavioral despair model, the continuous administration of EML(100 mg/kg)for 7 days significantly reduced the immobility time in the tail suspension test and forced swimming test. Compared with the vehicle group, the inhibitory rates of immobility time were 35.5% and 41%(P<0.05, P<0.01)in the tail suspension test and forced swimming test, respectively. The single treatment with EML(400 mg/kg)also significantly reduced the immobility time in the tail suspension and forced swimming test, and the inhibitory rates of immobility time were 29.1% and 35.3%, respectively(P<0.05). The results of spontaneous activity test showed that EML had no excitatory or inhibitory effect on the central nervous system in mice. In the 5-HTP induced head-twitch test in mice, the single treatment with EML(100 mg/kg)significantly increased the number of head-twitches in mice. In the yohimbine toxicity potentiation test, the single treatment with EML(100, 200 and 400 mg/kg)had no significant effect on the mortality rate in yohimbin-treated mice. In the reserpine test, compared with the model group, the single treatment with EML(400 mg/kg)antagonized reserpine induced ptosis (P<0.05)and had no significant effect on the decrease in rectal temperature and akinesia. Conclusion: EML showed antidepressant effect, and the action mechanism was likely related to the enhancement of the function of serotonergic nervous system.

Inhibition of endoplasmic reticulum stress in high-fat-diet-induced obese C57BL/6 mice: Efficacy of a novel extract from mulberry (Morus alba) leaves fermented with Cordyceps militaris / 한국실험동물학회지

A few clues about correlation between endoplasmic reticulum (ER) stress and mulberry (Morus alba) leaves were investigated in only the experimental autoimmune myocarditis and streptozotocin-induced diabetes. To investigate whether a novel extract of mulberry leaves fermented with Cordyceps militaris (EMfC) could suppress ER in fatty liver, alterations in the key parameters for ER stress response were measured in high fat diet (HFD)-induced obese C57L/6 mice treated with EMfC for 12 weeks. The area of adipocytes in the liver section were significantly decreased in the HFD+EMfC treated group as compared to the HFD+Vehicle treated group, while their level was higher in HFD+Vehicle treated group than No treated group. The level of the eukaryotic initiation factor 2 alpha (eIF2α) and inositol-requiring enzyme 1 beta (IRE1α) phosphorylation and CCAAT-enhancer-binding protein homologous protein (CHOP) expression were remarkably enhanced in the HFD+Vehicle treated group. However, their levels were restored in the HFD+EMfC treated group, although some differences were detected in the decrease rate. Similar recovery was observed on the ER stress-induced apoptosis. The level of Caspase-3, Bcl-2 and Bax were decreased in the HFD+EMfC and HFD+orlistat (OT) treated group compared to the HFD+Vehicle treated group. The results of the present study therefore provide first evidence that EMfC with the anti-obesity effects can be suppressed ER stress and ER stress-induced apoptosis in the hepatic steatosis of HFD-induced obesity model.

Influence of mulberry leaf extract on serum adiponectin, visfatin and lipid profile levels in type 2 diabetic rats

ABSTRACT The effect of ethanolic mulberry leaf extract (MLE) and mulberry leaf powder (MLP) on glycemic control, serum adiponectin, visfatin and lipid profile in type2 diabetic rats have been investigated. 30 male wistar rats randomly divided into 5 groups. One group was randomly assigned as control (I) and diabetes was induced in others by administration of streptozotocin (STZ) (55 mg/kg body weight) 15 minutes after the administration of nicotinamide (110 mg/kg body weight) intraperitoneally. Finally, fasting blood glucose (FBG), lipid profile, adiponectin and visfatin were assessed after 6 weeks. Lipid profiles including serum FBG, total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-c), very low-density lipoprotein cholesterol (VLDL) and visfatin significantly decreased and high-density lipoprotein cholesterol (HDL-c) and adiponectin increased in the two groups of treated diabetic rats in comparison to the diabetic control (p<0.05). For all the investigated factors, there was no significant difference between two treatment methods. However, MLP was more effective than MLE in improving visfatin. Results showed that MLE and MLP possess hypoglycemic and hypolipidemic activities and play an important role in regulating the secretion of adipokines such as adiponectin and visfatin.

Sustained-release effect of Na-montmorillonite on 1-deoxynojirimycin in alkaloid fraction of mulberry leaf extract / 中国药学杂志

OBJECTIVE: To investigate the sustained-release ability of Na-montmorillonite (Na-MMT) on 1-deoxynojirimycin (DNJ) in mulberry leaf extract (MLE). METHODS: In order to prepare DNJ-MMT composite, DNJ was intercalated into the inter-layer of MMT by stirring. Time and temperature for adsorption and ratio of DNJ to MMT were determined by calculating the loading of DNJ, then in vitro release experiment was carried out to estimate the sustained-release characteristics of DNJ-MMT. RESULTS: DNJ-MMT composite with a drug loading of 111.64 mg·g-1 was obtained by stirring 5.00 g Na-MMT and 16.00 g MLE containing 4016.0 mg DNJ in 1000 mL deionized water at 100℃ for 1 h. The composite released DNJ quickly in water, potassium phosphate buffer (pH 7.4), and 0.1 mol·L-1 hydrochloric acid solution. With the increasing of volume of hydrochloric acid solution, the release ratio of DNJ also increased correspondingly. CONCLUSION: The sustained-release effect of Na-MMT on DNJ is proved. Na-MMT can be used for study of DNJ sustained-release preparations.

Changes of secondary metabolites and differential proteomics in mulberry leaves under UV-B induction / 中国药学杂志

OBJECTIVE: To investigate the influence of ultraviolet B (UV-B) induction on the content of two kinds of secondary metabolites in mulberry leaves and differential proteomics under UV-B induction. METHODS: The HPLC chromatograms of secondary metabolites in leaves before and after UV-B induction were established and quantitative analysis of two kinds of secondary metabolites was performed. The subcellular structure of mulberry leaves under UV-B induction was observed using transmission electron microscopy. Proteomic analysis of mulberry leaves was performed using two-dimensonal electrophoresis (2-DE). RESULTS: The subcellular structure of mulberry leaves was destroyed under UV-B induction. The contents of moracin N and chalcomoracin in mulberry leaves were increased with the dark incubation time and they maximized at 36 and 40 h, respectively. The result of proteomics showed that the abundance of chalcone synthase (CHS) which is the key enzyme of flavonoid biosynthesis pathway was increased significantly. CONCLUSION: The secondary metabolism especially for flavonoids biosynthesis in mulberry leaves is changed under UV-B induction and dark incubation, which result in the increased moracin N and chalcomarcin.

Clarification Process of Mulberry Leaf Extracts with ZTC1+1Ⅱ Natural Clarifying Agent / 医药导报

Objective To determine the optimum process of ZTC1+1Ⅱnatural clarifying agents edulcorated mulberry leaf extracts. Methods The remaining rate of mulberry leaf alkaloid,flavone,polysaccharide and the solids removal rate were used as indexes,optimized by single factor experiment to study the effect of some factors,such as the order and dosage of clarifying agents,the concentration and the temperature of the extracting solution,whisking time,whisking speed and holding time,response surface methodology was selected to decide the best clarfication process. Results The optimal process:the order of the ZTC1+1Ⅱ natural clarifying agents was part B after part A,the dosage of clarifiers B and A were 10% and 5%volume of the extract,the extract solution was 0.17 g·mL-1 ,the temperature was 76 ℃,the whisking speed was 120 r·min-1 , the whisking time was 10 min,80 ℃ holding 30 min,and standing time was 12 h,the remaining rate of mulberry leaf alkaloid, flavone and polysaccharide were 92.5%,90.2% and 91.1%,the solids removal rate was 26.5%. Conclusion ZTC1+1Ⅱnatural clarifying agents could effectively purify the extracts of mulbery leaf,optimized by the response surface method,the method is simple and feasible,and clarity is good.

Optimization of the Ultrasonic Extraction Process of Total Alkaloids from Mulberry Leaves by Response Surface Method / 中国药房

OBJECTIVE:To optimize the ultrasonic extraction process of total alkaloids from mulberry leaves. METHODS:Based on the single factor experiment,response surface method was adopted to investigate the effects of ultrasonic extraction time, ultrasonic power,ethanol volume fraction,solid-liquid ratio and pH of solvent on the extraction rate of total alkaloids from mulber-ry leaves,then test data were analyzed by Design Expert 8.0.5 software,and the optimized process was confirmed and verified. RE-SULTS:The multiple correlation coefficient of established binomial equation fitting model was 0.969 9;the optimized condition for extracting alkaloid from mulberry leaf was ultrasonic extraction time of 48 min,ultrasonic extraction power of 800 W,ethanol vol-ume fraction of 70%,material-liquid ratio of 1∶25,pH 5. Under these conditions,the extraction rate of total alkaloids was 0.422%, with the bias ratio was less than 2% compared with the model predictions. CONCLUSIONS:The established model has good fit-ting performance,the extraction process is stable and reliable,and can be used for the extraction of alkaloids from mulberry leaves.

Anti-adipogenic effect of mulberry leaf ethanol extract in 3T3-L1 adipocytes

BACKGROUND/OBJECTIVES: Adipogenesis is part of the cell differentiation process in which undifferentiated fibroblasts (pre-adipocytes) become mature adipocytes with the accumulation of lipid droplets and subsequent cell morphological changes. Several transcription factors and food components have been suggested to be involved in adipogenesis. The aim of this study was to determine whether mulberry leaf ethanol extract (MLEE) affects adipogenesis in 3T3-L1 adipocytes. MATERIALS/METHODS: The 3T3-L1 adipocytes were treated with different doses of MLEE for 8 days starting 2 days post-confluence. Cell viability, fat accumulation, and adipogenesis-related factors including CCAAT-enhancer-binding protein alpha (C/EBPalpha), peroxisome proliferator-activated receptor gamma (PPARgamma), PPARgamma coactivator 1 alpha (PGC-1alpha), fatty acid synthase (FAS), and adiponectin were analyzed. RESULTS: Results showed that MLEE treatments at 10, 25, 50, and 100 microg/ml had no effect on cell morphology and viability. Without evident toxicity, all MLEE treated cells had lower fat accumulation compared with control as shown by lower absorbances of Oil Red O stain. MLEE at 50 and 100 microg/ml significantly reduced protein levels of PPARgamma, PGC-1alpha, FAS, and adiponectin in differentiated adipocytes. Furthermore, protein level of C/EBPalpha was significantly decreased by the treatment of 100 microg/ml MLEE. CONCLUSION: These results demonstrate that MLEE treatment has an anti-adipogenic effect in differentiated adipocytes without toxicity, suggesting its potential as an anti-obesity therapeutic.

Antimicrobial Activity of Mulberry Leaf against Mutans Streptococci and Periodontopathogens

This study investigated the antimicrobial activity of methanol extract of mulberry leaf against 16 strains of mutans streptococci and four species of periodontopathogens: Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans. The antimicrobial activities of the crude extracts or silica gel chromatography fractions of methanol-extracted mulberry leaf were evaluated by determining minimal inhibitory concentrations using an established microdilution method. The cytotoxicity of the extracts of mulberry leaf on KB cells was tested by the methyl thiazolyl tetrazolium assay. Chromatography fraction 12 displayed the most potent antimicrobial activity against all 16 strains of mutans streptococci, P. gingivalis, and P. intermedia. No KB cell cytotoxicity was evident up to 128 microg/ml of fraction 12. The methanol extract had no antimicrobial activity against F. nucleatum and A. actinomycetemcomitans. These results suggest chromatography fraction 12 methanol extract of mulberry leaf could be useful in the development of oral hygiene products, such as dentifrice and oral hygiene solution, for the prevention of dental caries.

Red ginseng extract increases the functional components of silkworm Bombyx mori L. used as an anti-diabetes medicinal resource / 동물의과학연구지

The anti-diabetes mechanism of silkworm Bombyx mori L. powder and extracts was found to inhibit the activity of alpha-glycosidase. The major functional component of silkworm powder was 1-deoxynojirimycin (1-DNJ), which exerts a blood glucose-lowering effect. In this study, we aimed to compare the effects of the supplements, including red ginseng extract on the functional components of silkworm. Fifty silkworm larvae were divided into the control group (Con, N=50), group A (A, artificial diet 95% and mulberry leaf powder 5%), group B (B, artificial diet 95% and mulberry powder 5%), group C (C, artificial diet 95% and Rubus coreanus remainders 5%), group D (D, artificial diet 95% and red ginseng extract 5%), and group E (E, artificial diet 95% and yeast powder (Saccharomyces cerevisiae). Body weights and length of silkworm larvae showed significant improvement in group A, D. In particular, the growth rate in group D (artificial diet 95% and red ginseng extract 5%) was larger than that of Con. In addition, the results showed that 1-DNJ concentration was significantly largest in group D. From these results, it is concluded that the addition of red ginseng extract may be effective for larval growth and 1-DNJ accumulation in silkworm rearing with an artificial diet.

Growth inhibitory effect of mulberry leaf extract on Streptococcus mutans in vitro / 대한구강보건학회지

No abstract available.

Postprandial hypoglycemic effect of mulberry leaf in Goto-Kakizaki rats and counterpart control Wistar rats

Postprandial hypoglycemic effect of mulberry leaf (Morus alba L.) was compared in two animal models: Goto-Kakizaki (GK) rats, a spontaneous non-obese animal model for type II diabetes, and their counterpart control Wistar rats. First, the effect of a single oral administration of mulberry leaf aqueous extract (MLE) on postprandial glucose responses was determined using maltose or glucose as substrate. With maltose-loading, MLE reduced peak responses of blood glucose significantly in both GK and Wistar rats (P < 0.05), supporting the inhibition of alpha-glucosidase by MLE in the small intestine. With glucose-loading, MLE also significantly reduced blood glucose concentrations, measured at 30 min, in both animal models (P < 0.01), proposing the inhibition of glucose transport by MLE. Next, dried mulberry leaf powder (MLP) was administered for 8 weeks by inclusion in the diet. By MLP administration, fasting blood glucose was significantly reduced at weeks 4 and 5 (P < 0.05), but then returned to values that were similar to those of the control at the end of experimental period in GK rats. Insulin, HOMA-IR, C-reactive protein, and triglycerides tended to be decreased by MLP treatment in GK rats. All other biochemical parameters were not changed by MLP administration in GK rats. Collectively, these findings support that MLE has significant postprandial hypoglycemic effect in both non-obese diabetic and healthy animals, which may be beneficial as food supplement to manage postprandial blood glucose. Inhibitions of glucose transport as well as alpha-glucosidase in the small intestine were suggested as possible mechanisms related with the postprandial hypoglycemic effect of MLE.

Study on TLC Identification for Tangfuping Capsule / 中国中医药信息杂志

Objective To establish a TLC method of identification for Tangfuping Capsule. Methods Mulberry leaf, Ginseng, Bee glue in Tangfuping Capsule were identified by TLC. Results Mulberry leaf, Ginseng, Bee glue in Tangfuping Capsule could be identified by TLC. Conclusion The method is simple and sensitive with strong specificity and reproducibility, and can be used for the quality control of Tangfuping Capsule.

Study on hypoglycemic effect of mulberry leaf powder in diabetic experimental mice

We extracted, determined preliminary chemical compounds and antioxidant activity of mulberry leaf exttact powder in a our previous research. This continous research is on evaluation of hypoglycemic effect of mulberry leaf extract powder in experimental animals. Objectives: (1) Evaluation of hypoglycemic effect of mulberry leaf extract powder in mice after drinking starch; (2) Evaluation of hypoglycemic effect of mulberry leaf extract powder in diabetic experimental mice. Methods: evaluation of hypoglycemic effect of mulberry leaf extract powder at doses 600mg/kg and 300mg/kg in two mice experimental models: mice after drinking starch and diabetic experimental mice. Results: mulberry leaf extract powder at doses 600 mg/kg and 300 mg/kg have a hypoglycemic effect in starch drunk mice. It is best at second hour with reduces of glucocemia of 18.6 % and 9.2 % after drinking starch, respectively. Mulberry leaf extract powder at both doses of 600 mg/kg and 300 mg/kg have hypoglycemic effects at levels of 29.6 %; 18.5 % in diabetic mice injected STZ of 150 mg/kg. But mulberry leaf extract powder at both doses of 600 mg/kg and 300 mg/kg have not hypoglycemic effect in diabetic mice injected STZ of 300 mg/kg. Conclusion: Mulberry leaf extract powder at doses of 600 mg/kg, 300 mg/kg have hypoglycemic effects in starch drunk mice and diabetic mice injected STZ of 150 mg/kg.

Extraction, determination of polyphenol concentration and antioxidant activities of mulberry leaf extract powders

It has been being some studies on biomedical effects of mulberry leaves in the world. Mulberry trees are widly cultivated in VietNam to take leaves for fed of silkworm. However, there were few studies on extraction, determination and antioxidation of mulberry leaves in VietNam. Objectives: extraction and determination of polyphenol from mulberry leaves. Evaluation of antioxidant capacities of mulberry leaf extract powders. Methods: Mulberry leaf extract powder were extracted from mulberry leaves by five solvens: methanol 100%, methanol 75%, n-hexan 100%, ethylacetat 100%. Polyphenol concentration of the extracts are determined by ferrous sulphate and follin reagent assay. Antioxidant capacities of the powders are based on peroxidation of linoleic acid at 40oC. Results: Among five solvens, the extract by methanol 75% from 50g dried leaves is best. The powder is 1.94g with 2.62% of polyphenol. Polyphenol concentraion of the extract powders are determined by two methods: ferrous sulphate and follin reagent. The result with ferrous sulphate method is more accurate than follin reagent method. The mulberry leave extract powders inhibited linoleic acid peroxidation at the 1h and 12h of reaction (only 15.5% to 42.2% linoleic acid peroxidated) in comparison with control (100% linoleic acid peroxidated). Conclusions: Polyphenol from mulberry leaves was extracted by some solvens. Among them extraction of polyphenol by methanol 75% is best. Polyphenol concentration of extract powders can be dedermined by ferrous sulphat. The extract powders from mulberry leaves exhibited antioxidant capacities in vitro. The extract powder by methanol 75% showed highest antioxidant capacitiy.

Effects of Mulberry Leaf Powder Supplementation on Lead Status and Minerals content in Pb-administered Rats

This study was designed to investigate the effects of mulberry leaf powder supplementation on lead (Pb) status and mineral (Ca, Fe, Cu and Zn) content in Pb-administered rats for 4 weeks. Thirty two male rats were divided into 4 groups: a control, Pb, Pb5M (500 ppm Pb + 5% mulberry leaf powder), and Pb10M (500 ppm Pb + 10% mulberry leaf powder). There were no significant differences in food intake and initial body weight among groups. Mulberry leaf powder treatments showed significant decreases in food efficiency ratio and body weight gain. But FER of Pb5M% and Pb10M were significantly increases than that of Pb group. The levels of serum aspartate transaminase (AST) and creatinine were decreased by mulberry leaf powder treatment. Minerals content of liver and kidney were significantly decreased in the Pb groups than that of control group. Whereas, fecal minerals content were significantly increased in the Pb5M and Pb10M than those of control group. Pb content of serum, liver and kidney was significantly increased in the Pb group than those of control group. However, by mulberry leaf powder administration (Pb5M and Pb10M), Pb level of serum, liver and kidney were lowered than that of Pb group. And fecal Pb excretion was significantly increased in the Pb5M and Pb10M than that of Pb group. These results showed mulberry leaves were effective for lowing Pb accumulation in serum, organs, which may have potential to prevent Pb toxicity.

Extraction and isolation technology of polysaccharide from mulberry leaves / 中草药

ZHANG Lin-hua, GAO Rui-chang, XU Ming-li (School of Chemical Engineering, Tianjin University, Tianjin 300072, China)