Effect of different planting areas on the chemical compositions and hypoglycemic and antioxidant activities of mulberry leaf extracts in Southern China

Effect of growing regions on morphological characteristics, protein subfractions, rumen degradation and molecular structures of various whole-plant silage corn cultivars

Little information exists on the variation in morphological characteristics, nutritional value, ruminal degradability, and molecular structural makeup of diverse whole-plant silage corn (WPSC) cultivars among different growing regions. This study investigated the between-regions (Beijing, Urumchi, Cangzhou, Liaoyuan, Tianjin) discrepancies in five widely used WPSC cultivars in China (FKBN, YQ889, YQ23, DK301 and ZD958), in terms of 1) morphological characteristics; 2) crude protein (CP) chemical profile; 3) Cornell Net Carbohydrate and Protein System (CNCPS) CP subfractions; 4) in situ CP degradation kinetics; and 5) CP molecular structures. Our results revealed significant growing region and WPSC cultivar interaction for all estimated morphological characteristics (P < 0.001), CP chemical profile (P < 0.001), CNCPS subfractions (P < 0.001) and CP molecular structural features (P < 0.05). Except ear weight (P = 0.18), all measured morphological characteristics varied among different growing regions (P < 0.001). Besides, WPSC cultivars planted in different areas had remarkably different CP chemical profiles and CNCPS subfractions (P < 0.001). All spectral parameters of protein primary structure of WPSC differed (P < 0.05) due to the growing regions, except amide II area (P = 0.28). Finally, the area ratio of amide I to II was negatively correlated with the contents of soluble CP (δ = -0.66; P = 0.002), CP (δ = -0.61; P = 0.006), non-protein nitrogen (δ = -0.56; P = 0.004) and acid detergent insoluble CP (δ = -0.43; P = 0.008), in conjunction with a positive correlation with moderately degradable CP (PB1; δ = 0.58; P = 0.01). In conclusion, the cultivar of DK301 exhibited high and stable CP content. The WPSC planted in Beijing showed high CP, SCP and NPN. The low rumen degradable protein of WPSC was observed in Urumchi. Meanwhile, above changes in protein profiles and digestibility were strongly connected with the ratio of amide I and amide II.

Evaluating the Effects of Replacing Alfalfa with Broussonetia papyrifera Branch/Leaf Powder on Growth and Serum Indicators in Dezhou Donkeys

The purpose of this experiment was to study the apparent digestibility and the effects of Broussonetia papyrifera (BP) branch/leaf powder supplementation on growth performance and serum indicators in donkeys. The results showed that the apparent digestibility of dry matter (DM), crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), acidic detergent fiber (ADF), and digestible energy content (DE) of BP branch/leaf powder were 51.88%, 67.27%, 64.86%, 49.59%, 54.73%, 40.87%, and 6.37 MJ/kg, respectively. The average daily gain (ADG) in the 20% group was significantly higher than in the 0% and 30% groups. The serum albumin (ALB) levels in the 0% and 10% groups were significantly higher than those in the 20% and 30% groups, while the serum globulin (GLB) content in the 10% group was significantly lower than in the other groups. The 20% group showed decreased serum triglyceride (TG) levels compared to the other groups. Both the 20% and 30% groups exhibited lower total cholesterol (TC) levels and increased alanine aminotransferase (ALT) compared to the 0% and 10% groups and higher serum lactate dehydrogenase (LDH) levels than the 10% group. The 30% group had higher serum immunoglobulin A (IgA) levels than the other groups, while all three BP branch/leaf powder groups had lower serum tumor necrosis factor (TNF-α) levels than the 0% group. There was a gradual increase in serum total antioxidant capacity (T-AOC) with the increasing amount of BP branch/leaf powder added. In conclusion, the optimal supplemental proportion of BP branch/leaf powder in the diet is 20%. Furthermore, BP branch/leaf powder can improve growth performance, serum immune indices, and antioxidant capacity in Dezhou donkeys.

Evaluation of mulberry leaves’ hypoglycemic properties and hypoglycemic mechanisms

The effectiveness of herbal medicine in treating diabetes has grown in recent years, but the precise mechanism by which it does so is still unclear to both medical professionals and diabetics. In traditional Chinese medicine, mulberry leaf is used to treat inflammation, colds, and antiviral illnesses. Mulberry leaves are one of the herbs with many medicinal applications, and as mulberry leaf study grows, there is mounting evidence that these leaves also have potent anti-diabetic properties. The direct role of mulberry leaf as a natural remedy in the treatment of diabetes has been proven in several studies and clinical trials. However, because mulberry leaf is a more potent remedy for diabetes, a deeper understanding of how it works is required. The bioactive compounds flavonoids, alkaloids, polysaccharides, polyphenols, volatile oils, sterols, amino acids, and a variety of inorganic trace elements and vitamins, among others, have been found to be abundant in mulberry leaves. Among these compounds, flavonoids, alkaloids, polysaccharides, and polyphenols have a stronger link to diabetes. Of course, trace minerals and vitamins also contribute to blood sugar regulation. Inhibiting alpha glucosidase activity in the intestine, regulating lipid metabolism in the body, protecting pancreatic -cells, lowering insulin resistance, accelerating glucose uptake by target tissues, and improving oxidative stress levels in the body are some of the main therapeutic properties mentioned above. These mechanisms can effectively regulate blood glucose levels. The therapeutic effects of the bioactive compounds found in mulberry leaves on diabetes mellitus and their associated molecular mechanisms are the main topics of this paper’s overview of the state of the art in mulberry leaf research for the treatment of diabetes mellitus.

Fermentation Properties and Bacterial Community Composition of Mixed Silage of Mulberry Leaves and Smooth Bromegrass with and without Lactobacillus plantarum Inoculation

To evaluate the fermentation properties and bacterial community composition of mulberry leaves when ensiled with smooth bromegrass, and the effects of Lactobacillus plantarum inoculation on the mixed silage of mulberry leaves and smooth bromegrass, mulberry leaves were mixed with smooth bromegrass at ratios of 100:0, 90:10, 80:20, 70:30 and 60:40, and ensiled for 60 d with and without L. plantarum inoculant. The results showed that the sole fermentation of mulberry leaves failed to achieve optimum fermentation quality. Silage with a mulberry leaf ratio of 80% performed better fermentation quality compared with other non-inoculated groups, indicated by lower pH value, adequate lactic acid accumulation, and enriched proportion of Lactobacillus in the bacterial community. L. plantarum inoculation dramatically improved fermentation quality of mulberry leaf silage compared with the non-inoculated control. However, the fermentation quality of the inoculated silage decreased along with the reduction in the ratio of mulberry leaves. In conclusion, L. plantarum inoculation has the capability to improve the silage quality of mulberry leaves. Combined ensiling with smooth bromegrass could also aid in improving silage quality of mulberry leaves, with the optimum ratio of mulberry leaves being 80%.

Identification of geographic origins of Morus alba Linn. through surfaced enhanced Raman spectrometry and machine learning algorithms

The leaves of Morus alba Linn., which is also known as white mulberry, have been commonly used in many of traditional systems of medicine for centuries. In traditional Chinese medicine (TCM), mulberry leaf is mainly used for anti-diabetic purpose due to its enrichment in bioactive compounds such as alkaloids, flavonoids and polysaccharides. However, these components are variable due to the different habitats of the mulberry plant. Therefore, geographic origin is an important feature because it is closely associated with bioactive ingredient composition that further influences medicinal qualities and effects. As a low-cost and non-invasive method, surface enhanced Raman spectrometry (SERS) is able to generate the overall fingerprints of chemical compounds in medicinal plants, which holds the potential for the rapid identification of their geographic origins. In this study, we collected mulberry leaves from five representative provinces in China, namely, Anhui, Guangdong, Hebei, Henan and Jiangsu. SERS spectrometry was applied to characterize the fingerprints of both ethanol and water extracts of mulberry leaves, respectively. Through the combination of SERS spectra and machine learning algorithms, mulberry leaves were well discriminated with high accuracies in terms of their geographic origins, among which the deep learning algorithm convolutional neural network (CNN) showed the best performance. Taken together, our study established a novel method for predicting the geographic origins of mulberry leaves through the combination of SERS spectra with machine learning algorithms, which strengthened the application potential of the method in the quality evaluation, control and assurance of mulberry leaves.

Comparison of Nutritional Components, Ruminal Degradation Characteristics and Feed Value from Different Cultivars of Alfalfa Hay

The objective of this study was to evaluate the effects of different cultivars of alfalfa hay, including American Anderson (AA), American Golden Empress (GE), China Zhongmu No. 1 (ZM1) and China Gongnong No. 1 (GN1), on conventional nutrient composition, rumen degradation characteristics and feed value. Four healthy Holstein cows (137 ± 14 days in milk, 2.40 ± 0.50 parity) equipped with permanent ruminal cannulas were examined for the nylon-bag technique. The alfalfa hay samples were incubated in the rumen for 0, 4, 8, 12, 24, 36, 48 and 72 h according to the "gradual in/all out" schedule to detect the ruminal nutrients' degradability. Our results showed that various cultivars of alfalfa hay from different planting regions had significant differences on nutrient contents, rumen degradability and feed value. For nutritional components of alfalfa hay, the highest dry matter (DM) content was found in GE and the lowest in GN1 (p < 0.001); however, GN1 had the greatest concentration of ether extract (EE, p = 0.01), Ca (p < 0.001) and the lowest Ash (p < 0.001). Additionally, the lowest neutral detergent fiber (NDF), acid detergent fiber (ADF) and highest starch contents were observed in AA and GE (p < 0.001). Meanwhile, the cultivar of ZM1 represented the highest NDF, ADF and Ash contents, in conjunction with minimal CP and P concentrations (p < 0.001). In terms of rumen degradation characteristics, the effective degradation rate (ED) of DM in GE and ZM1 was significantly higher than that in AA and GN1 (p = 0.013). The NDF effective degradation was lower in ZM1 than the other three cultivars (p = 0.002), and in addition ZM1 also showed lower CP and ADF effective degradation than GE (p < 0.001). As far as feed value was concerned, the cultivar of alfalfa hay imported from the US, including AA and GE, exhibited higher relative feed value (RFV) and relative forage quality (RFQ) than Chinese alfalfa based on ZM1 and GN1 (p < 0.001). In conclusion, the results suggested that the cultivar of GE exhibited greater rumen degradable characteristics and feed value, while ZM1 showed the opposite status.

Elicitation of Stilbenes and Benzofuran Derivatives in Hairy Root Cultures of White Mulberry (Morus alba)

Stilbene and benzofuran derivatives isolated from the root of white mulberry (Morus alba) have shown various biological activities, including anti-inflammatory, antioxidant, and antimicrobial properties. The objectives of this study were to develop hairy root cultures and assess the effect of multiple elicitors combinations including (I) methyl-β-cyclodextrin (CD), MgCl2, methyl jasmonate (MeJA), and H2O2, (II) CD, MgCl2, and MeJA and (III) CD, MgCl2, and H2O2, on the production of these bioactive compounds. The highest yields of stilbenes and benzofurans were obtained upon co-treatment with 18 g/L CD, 3 mM H2O2 and 1 mM MgCl2. The stilbenes oxyresveratrol, resveratrol, and 3'-prenylresveratrol accumulated up to 6.27, 0.61, and 5.00 mg/g DW root, respectively. Meanwhile, the aryl benzofurans moracin M and moracin C accumulated up to 7.82 and 1.82 mg/g DW root, respectively. These stilbenes and benzofurans accumulated in the culture medium of the elicited hairy root cultures. They were not detected in the root tissue. However, the oxyresveratrol diglucoside mulberroside A was only detected in the root tissue with yields up to 10.01 mg/g DW. The results demonstrated that co-treatment of white mulberry hairy root cultures with multiple elicitors can significantly enhance production and secretion of stilbenes and benzofurans in this controlled and sustainable axenic culture system.

Effect of Mulberry Leaf TMR on Growth Performance, Meat Quality and Expression of Meat Quality Master Genes (ADSL, H-FABP) in Crossbred Black Goats

This study was conducted to examine the effect of a mulberry leaf total mixed ration (TMR) diet on growth performance, apparent digestibility, meat quality and the expression of related meat-quality genes (ADSL, H-FABP) in crossbred black goats. Forty-four Guizhou crossbred black goats (Nubian black goat ♂ × Guizhou black goat ♀), weighing 33.43 ± 0.55 kg, were chosen. The goats were randomly divided into four groups, with 11 test replicates in each group. Group I was the control group and fed with the traditional feeding method of roughage and concentrate supplement without adding mulberry leaf. Group II was fed with a 40% mulberry leaf pellet TMR diet. Group III was fed with a freshly processed 40% mulberry leaf TMR diet. Group IV was fed with a 40% mulberry leaf fermented total mixed rations (FTMR) diet. The results showed that the average daily gain (ADG) of group II was significantly higher than that of group I and III (p < 0.05). The apparent digestibility of group II of ether extract (EE) and neutral detergent fiber (NDF) was significantly higher than that of group I (p < 0.05), and the apparent digestibility of dry matter (DM) and crude protein (CP) was significantly higher than that of group I (p < 0.01). Compared with group I, meat in group II had lower meat color lightness (L*) and yellowness (b*) values (p < 0.01) in the Longissimus thoracis et lumborum. The shear force of group II was significantly lower than that of group I (p < 0.05). The total fatty acids (TFA) of group II was significantly higher than that of groups I and III (p < 0.05), but the total saturated fatty acids (SFA) of group II was significantly lower that than of group I (p < 0.01). Subsequently, the Unsaturated fatty acids (USFA), Monounsaturated fatty acids (MUFA), and Polyunsaturated fatty acids (PUFA) of group II were significantly higher than those in group I (p < 0.01). The contents of total amino acids (TAA), total essential amino acids (EAA), total non-essential amino acids (NEAA) and total of major fresh-tasting amino acids (DAA) of groups II, III and IV were significantly higher than those of group I (p < 0.05), as well as the contents of IMP (p < 0.01). The expression of the H-FABP gene in the arm triceps of group II was significantly higher than that of groups I, III and IV (p < 0.05). The expression of the ADSL gene in the Longissimus thoracis et lumborum and biceps femoris of group II was significantly higher than that of group I (p < 0.05). Collectively, the results of the current study indicated that the mulberry leaf TMR diet improved the growth performance, apparent digestibility and expression of related meat-quality master genes (ADSL, H-FABP) in crossbred black goats, which promoted the deposition of intramuscular fat (IMF) and inosinic acid (IMP) and improved the composition of fatty acids and amino acids in the muscles.

The Effect of Hot-Melt Extrusion of Mulberry Leaf on the Number of Active Compounds and Antioxidant Activity

The aim of this study is to compare the functions of the physiologically active compounds of three types of mulberry leaf by cultivar, and to confirm the changes using hot-melt extrusion (HME-ML). The active components of mulberry leaf were analyzed using the HPLC system, and total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity were measured. Among the three varieties, the highest contents of rutin and isoquercetin were detected in Cheongil, of TPC in Cheongol, and of TFC in Cheongil. It was confirmed that this bio-accessibility was increased in HME-ML compared with the control. The DPPH radical scavenging activity of Cheongol showed greater antioxidant properties, and HME showed improvement in the antioxidant properties of all mulberry leaves. These results suggest that the application of HME technology can improve the biological activities of mulberry leaf.

The effects of mulberry (Morus alba Linn.) leaf supplementation on growth performance, blood parameter, and antioxidant status of broiler chickens under high stocking density

Background and Aim

A stocking density system in boilers is well known for increasing productivity. However, this system increases stress and affects the growth performance of broilers. Mulberry is a valuable plant with therapeutic applications in traditional medicine; moreover, it reduces free radicals and improves growth performance in broilers. This study was conducted to investigate the effects of mulberry on the blood biochemistry parameters and the antioxidant status of broilers exposed to various raising systems.

Materials and Methods

Two hundred and seventy-six 3-week-old male broilers were randomly assigned to nine categories composed of three growing systems: Semi-intensive, low stocking density, and high stocking density. Each group was fed with a control diet mixed with and without 10% mulberry leaf extract; the positive control group was provided with vitamin C. During the study, phytochemical screening of mulberry leaf extract, growth performances, hematological parameters, and antioxidant profiles were measured over the 4 weeks of the treatment.

Results

In the high stocking density group, lipid peroxidation gradually increased while antioxidant activities decreased; however, the level of lipid peroxidation was reduced, whereas catalase and superoxide dismutase activities were significantly increased. The growth performance and blood biochemistry were improved after being fed with 10% mulberry leaf extract.

Conclusion

This finding indicates that mulberry leaf extract reduced oxidative stress, activated antioxidant enzyme activities, and enhanced broilers' growth performance when raised under stress conditions.

Replacement of Maize Silage and Soyabean Meal with Mulberry Silage in the Diet of Hu Lambs on Growth, Gastrointestinal Tissue Morphology, Rumen Fermentation Parameters and Microbial Diversity

Simple Summary

A shortage of high-quality roughage jeopardises the Chinese mutton sheep industry. The development of new roughage resources is important to safeguard the health and welfare of the sheep, to save costs, increase efficiency and improve resource utilization. Mulberry leaves have high nutritional value and have been used in herbivore production for a long time in China. However, fresh mulberry leaves are not easy to preserve, and dried mulberry leaves readily lose nutrients in the conservation process. Ensiling mulberry leaves can reduce the anti-nutritional constituents, mainly phytic acid and tannin, while reducing any nutrient loss. In this study, mulberry silage replaced part of a maize silage-based diet for fattening Hu lambs. The effects of mulberry silage on the growth of the lambs, their gastrointestinal tissue morphology, rumen fermentation parameters and bacterial diversity were investigated. The results showed that using mulberry silage in place of 20–40% of the maize silage in the diet of Hu lambs promoted their growth, while maintaining satisfactory digestion.

Abstract

Maize silage has a significant environmental impact on livestock due to its high requirement for fertilizer and water. Mulberry has the potential to replace much of the large amount of maize silage grown in China, but its feeding value in the conserved form needs to be evaluated. We fed Hu lambs diets with 20–60% of the maize silage replaced by mulberry silage, adjusting the soybean meal content when increasing the mulberry silage inclusion rate in an attempt to balance the crude protein content of the diets. Mulberry silage had higher crude protein and lower acidic and neutral detergent fiber contents compared to maize silage. Replacing maize silage and soyabean meal with mulberry silage had no effect on the feed intake and growth rate of Hu lambs. However, the rumen pH increased, the acetate to propionate in rumen fluid increased, and the rumen ammonia concentration decreased as mulberry replaced maize silage and soyabean meal. This was associated with an increase in norank_f__F082 bacteria in the rumen. Rumen papillae were shorter when mulberry silage replaced maize silage, which may reflect the reduced neutral detergent fiber (NDF) content of the original silage. In conclusion, mulberry silage can successfully replace maize silage and soyabeans in the diet of Hu lambs without loss of production potential, which could have significant environmental benefits.

In vitro bioactivity evaluation of mulberry leaf extracts as nutraceuticals for the management of diabetes mellitus

There is an increasing need for new options to treat diabetes mellitus at its early stage and natural remedies have been recently reassessed as potential candidates owing to their low-cost and effectiveness. Genus Morus plants contain many active compounds with hypoglycaemic, hypolipidemic, and antioxidant effects. Current research on mulberry chemical composition and bioactivity has been generally carried out only on Asian cultivation, where this plant has been traditionally used in the form of leaf infusion for decades. In this work, twelve Italian mulberry cultivars were fully characterised to fill this gap of knowledge, since a strong correlation among composition, genetics and growing area was proven. Antiglycative and hypoglycaemic effects of leaf extracts were evaluated using different in vitro models. The results indicate that the inhibitory effect on carbohydrate digestive enzymes was likely mediated by 1-deoxynojirimycin, kaempferol, quercetin, and chlorogenic acid, acting in a synergistic way. Besides, the combined antiglycative and carbonyl trapping capacities, tested here for the first time, may help in preventing long-term complications related to AGEs in diabetic patients.

Mulberry leaf (Morus alba L.): A review of its potential influences in mechanisms of action on metabolic diseases

The leaves of Morus alba L. (called Sangye in Chinese, ML), which belong to the genus Morus., are highly valuable edible plants in nutrients and nutraceuticals. In Asian countries including China, Japan and Korea, ML are widely used as functional foods including beverages, noodles and herbal tea because of its biological and nutritional value. Meanwhile, ML-derived products in the form of powders, extracts and capsules are widely consumed as dietary supplements for controlling blood glucose and sugar. Clinical studies showed that ML play an important role in the treatment of metabolic diseases including the diabetes, dyslipidemia, obesity, atherosclerosis and hypertension. People broadly use ML due to their nutritiousness, deliciousness, safety, and abundant active benefits. However, the systematic pharmacological mechanisms of ML on metabolic diseases have not been fully revealed. Therefore, in order to fully utilize and scale relevant products about ML, this review summarizes the up-to-date information about the ML and its constituents effecting on metabolic disease.

Effects of Feeding Fermented Mulberry Leaf Powder on Growth Performance, Slaughter Performance, and Meat Quality in Chicken Broilers

Simple Summary

Mulberry leaf is widely used in ruminants feeding, such as sheep, beef cattle, and dairy calves. Due to the high content of crude fiber in mature mulberry leaves and branches and the presence of anti-nutritional factors such as tannin, excessive addition will affect the production performance and health of livestock and poultry, and limit its large-scale application in animal production to a certain extent. The disadvantages of woody plants can be improved by microbial fermentation, which can reduce the content of anti-nutritional factors, and increase the content of peptides and amino acids, probiotics, and bioactive components. In this study, Lactobacillus, Saccharomycetes, and Bacillus subtilis were used to make mixed strains to ferment mulberry leaf powder, and different proportions were added to the diet of yellow feathered chicken broilers. The results showed that the addition of fermented mulberry leaf in the diet could improve the digestion and absorption of nutrients, and then improve its growth performance, and increase the contents of inosine monophosphate (IMP), total amino acids, essential amino acids, and delicious amino acids in breast and thigh muscle, and improved polyunsaturated fatty acids and essential fatty acids in breast muscle; this also has a positive effect on improving meat quality.

Abstract

This study was conducted to investigate the effects of feeding fermented mulberry leaf powder (FMLP) on growth performance, slaughter performance, and meat quality of broilers. A total of 360 1-day-old chickens were randomly divided into 5 groups. The control group was fed basal diet (CON), 3% FMLP, 6% FMLP, 9% FMLP, and 3% unfermented mulberry leaf powder. The (MLP) group was fed basal diet supplemented with 3%, 6%, 9% fermented mulberry leaf powder, and 3% MLP, respectively. The experiment lasted for 56 days, with 1–28 days as the starter phase and 29–56 days as the grower phase. The results on the growth performance showed that diets supplemented with 3% FMLP significantly increased the ratio of villus height to crypt depth in the duodenum, jejunum, and ileum of broilers, enhanced the activity of intestinal amylase and digestibility of dry matter and crude protein, improved the average daily gain (ADG), and decreased the feed to gain ratio (F/G) (p < 0.05). Compared with the control group diet, the 3% FMLP group diet significantly increased the breast muscle yield (p < 0.05), reduced the abdominal fat ratio (0.1 < p < 0.05), and improved the slaughter performance of broilers. The 3% MLP group diet increased the shear force of breast muscle (p < 0.05) and thigh muscle of broilers compared to the control group, and adding FMLP could reverse the above results. Additionally, relative to the control group, FMLP supplementation improved the contents of inosine monophosphate (IMP), total amino acids (TAA), essential amino acids (EAA), and delicious amino acids (DAA) in breast and thigh muscle, and improved polyunsaturated fatty acids (PUFA) and essential fatty acids (EFA) in breast muscle; the 6% and 9% FMLP groups showed preferably such effects (p < 0.05). In conclusion, dietary supplementation of FMLP can improve the digestion and absorption of nutrients, and then improve the growth performance of broilers; it also has a positive effect on improving slaughter performance and meat quality.

Evaluation and development of a novel pre-treatment method for mulberry leaves to enhance their bioactivity via enzymatic degradation of GAL-DNJ to DNJ

Mulberry leaves are rich in 1-deoxynojirimycin (DNJ) and 2-O-α-D-galactopyranosyl-deoxynojirimycin (GAL-DNJ). Compared to DNJ, the bioactive potency of GAL-DNJ is low. We proposed that the conversion of GAL-DNJ into DNJ may improve its bioavailability. We evaluated this hypothesis and constructed a novel enzymatic-based method to induce the hydrolysis of GAL-DNJ to DNJ in order to improve the therapeutic potency of mulberry leaves.

A comprehensive review on the production, pharmacokinetics and health benefits of mulberry leaf iminosugars: Main focus on 1-deoxynojirimycin, d-fagomine, and 2-O-ɑ-d-galactopyranosyl-DNJ

Mulberry leaves are rich in biologically active compounds, including phenolics, polysaccharides, and alkaloids. Mulberry leaf iminosugars (MLIs; a type of polyhydroxylated alkaloids), in particular, have been gaining increasing attention due to their health-promoting effects, including anti-diabetic, anti-obesity, anti-hyperglycemic, anti-hypercholesterolemic, anti-inflammatory, and gut microbiota-modulatory activities. Knowledge regarding the in vivo bioavailability and bioactivity of MLIs are crucial to understand their role and function and human health. Therefore, this review is aimed to comprehensively summarize the existing studies on the oral pharmacokinetics and the physiological significance of selected MLIs (i.e.,1-deoxynojirimycin, d-fagomine, and 2-O-ɑ-d-galactopyranosyl-DNJ). Evidence have suggested that MLIs possess relatively good uptake and safety profiles, which support their prospective use for oral intake; the therapeutic potential of these compounds against metabolic and chronic disorders and the underlying mechanisms behind these effects have also been studied in in vitro and in vivo models. Also discussed are the biosynthetic pathways of MLIs in plants, as well as the agronomic and processing factors that affect their concentration in mulberry leaves-derived products.

Effects of enzymatic hydrolysis on physicochemical property and antioxidant activity of mulberry (Morus atropurpurea Roxb.) leaf protein

To improve the antioxidant efficiency of mulberry leaf protein (MLP), alcalase, protamex, papain, flavourzyme, neutrase, and trypsin were used to hydrolyze MLP. The yield of soluble peptides, secondary structures, molecular weight distributions, and antioxidant activities of MLP hydrolysates (MLPHs) were investigated. Results showed that the native MLP was rich in the fraction above 6.5 kDa and was mainly composed of β-sheets, while MLPHs were abundant in the fractions of 0.3-0.6 kDa and 0.6-6.5 kDa and were mainly composed of disordered coils and β-folds. Limited hydrolysis of MLP could lead to better antioxidant activity than extensive hydrolysis. After enzymatic hydrolysis, the content of total sugar and total phenol in MLP increased significantly. MLP hydrolysates prepared with neutrase, alcalase, and protamex were preferable to other enzymes. Meanwhile, an enzyme to substrate level of 1% and a hydrolysis time of 2 hr were the optimum conditions to obtain higher antioxidant hydrolysates using neutrase.

Combined enzymatic hydrolysis and herbal extracts fortification to boost in vitro antioxidant activity of edible bird’s nest solution

Objective

Edible bird’s nest (EBN) is a popular traditional tonic food in Chinese population for centuries. Malaysia is one of the main EBN suppliers in the world. This study aims to explore the best strategy to boost the antioxidant potential of EBN solution.

Methods

In this study, the raw EBN (4%, mass to volume ratio) was initially enzymatic hydrolyzed using papain enzyme to produce EBN hydrolysate (EBNH), then spray-dried into powdered form. Next, 4% (mass to volume ratio) of EBNH powder was dissolved in ginger extract (GE), mulberry leaf extract (MLE) and cinnamon twig extract (CTE) to detect the changes of antioxidant activities, respectively.

Results

Results obtained suggest that enzymatic hydrolysis significantly reduced the viscosity of 4% EBN solution from (68.12 ± 0.69) mPa·s to (7.84 ± 0.31) mPa·s. Besides, the total phenolic content (TPC), total flavonoid content (TFC), total soluble protein, DPPH scavenging activity and ferric reducing antioxidant power (FRAP) were substantially increased following EBN hydrolysis using papain enzyme. In addition, fortification with GE, MLE and CTE had further improved the TPC, TFC, DPPH scavenging activity and FRAP of the EBNH solution. Among the samples, MLE-EBNH solution showed the most superior antioxidant potential at (86.39 ± 1.66)% of DPPH scavenging activity and (19.79 ± 2.96) mmol/L FeSO₄ of FRAP.

Conclusion

This study proved that combined enzymatic hydrolysis and MLE fortification is the best strategy to produce EBN product with prominent in vitro antioxidant potential. This preliminary study provides new insight into the compatibility of EBN with different herbal extracts for future health food production.

Determination of 1-Deoxynojirimycin (1-DNJ) in Leaves of Italian or Italy-Adapted Cultivars of Mulberry (Morus sp.pl.) by HPLC-MS

Recently, 1-DNJ has been widely studied by scientists for its capacity to inhibit α-glucosidase and reduce postprandial blood glucose and fat accumulation. To the best of our knowledge, this is the first analytical determination of 1-DNJ in Morus sp.pl. leaves carried out on Italian crops, and it could be used as a reference to assess the quality of the plant material in comparison to Far Eastern Asia cultivations. The effects of two thermal treatments were compared to test the incidence of the drying process on the 1-DNJ extractability. In addition, two harvesting seasons in the same year (2017) and two subsequent harvesting years (2017-2018) were considered. The amount of 1-DNJ herein found was comparable to that reported in the scientific literature for Asian cultivations. The increase in 1-DNJ along the summer and the higher level of this compound in the apical leaves also complies with previous findings. However, a strong implication for the climatic conditions in the different years and a significant interaction between climate and genotypes suggest exploring very carefully the agronomic practices and selecting cultivars according to different environmental conditions with a view to standardize the 1-DNJ amount in leaves.

Effects of mulberry (Morus alba L.) Leaf extracts on growth, immune response, and antioxidant functions in nile tilapia (Oreochromis niloticus)

This study evaluates how white mulberry (Morus alba L.) leaf extracts affect the growth, antioxidant activity, and immune response in Nile tilapia Oreochromis niloticus. Mulberry leaf extracts were obtained through aqueous extraction (AE) and ethanol extraction (EE). Powder of mulberry leaf (PML) was added directly to feed and compared with the effects of feeds supplemented with the different extracts. Fish were divided into eight groups for an 8-week feeding trial where they were fed the basal diet or supplementation with 10% PML, 10% AE, 20% AE, 40% AE, 10% EE, 20% EE, or 40% EE. The inclusion of mulberry leaf extract obtained with either method showed better effects on fish growth performance, antioxidant activities and acid phosphatase activity (ACP) in serum, immune cytokine expression, and intestinal morphology as compared with controls or fish fed the 10% PML diet. The specific growth rate was significantly higher in the 10% AE, 10% EE, and 20% EE groups compared with all other groups (P<0.05). Catalase activity was significantly greater in most groups fed an extract, and in the 10% PML group, when compared with controls. Similarly, ACP, interleukin (IL)-1, and IL-2 expression was significantly increased in groups fed an extract, and in the 10% PML group, when compared with controls (P<0.05). IL-1, IL-2, IL-10, and Toll-like receptor 2 expression was significantly greater in the 10% EE group than in the 10% PML and 10% AE groups (P<0.05). Villus length in the middle intestine was significantly increased in the 10% AE and 10% EE groups compared with controls and the 10% PML group (P<0.05). Thus, 10% mulberry leaf ethanol extract added to feed is recommended for enhancing the growth rate and health of cultured Nile tilapia.

Morus alba L. Plant: Bioactive Compounds and Potential as a Functional Food Ingredient

Morus alba L. (M. alba) is a highly adaptable plant that is extensively incorporated in many traditional and Ayurveda medications. Various parts of the plant, such as leaves, fruits, and seeds, possess nutritional and medicinal value. M. alba has abundant phytochemicals, including phenolic acids, flavonoids, flavonols, anthocyanins, macronutrients, vitamins, minerals, and volatile aromatic compounds, indicating its excellent pharmacological abilities. M. alba also contains high nutraceutical values for protein, carbohydrates, fiber, organic acids, vitamins, and minerals, as well as a low lipid value. However, despite its excellent biological properties and nutritional value, M. alba has not been fully considered as a potential functional food ingredient. Therefore, this review reports on the nutrients and bioactive compounds available in M. alba leaves, fruit, and seeds; its nutraceutical properties, functional properties as an ingredient in foodstuffs, and a microencapsulation technique to enhance polyphenol stability. Finally, as scaling up to a bigger production plant is needed to accommodate industrial demand, the study and limitation on an M. alba upscaling process is reviewed.

Simultaneous optimization of ultrasound-assisted extraction for total flavonoid content and antioxidant activity of the tender stem of Triarrhena lutarioriparia using response surface methodology

The asparagus of Triarrhena lutarioriparia (TL) is a popular vegetable with abundant chemical compounds in China. This study aims to optimize the ultrasound-assisted extraction (UAE) method for its content of total flavonoid and antioxidant activities by response surface methodology (RSM). Box-Behnken design was adopted to evaluate the influences of ethanol concentration, extraction time and solvent-to-sample ratio on the extraction yield of total flavonoid and the antioxidant activity. Considering the maximum content of extracted total flavonoids and antioxidant activity, the optimal extraction conditions were acquired with 70% (v/v) ethanol by UAE for 60 min at a solvent-to-sample ratio of 40 mL/g. The proportion of the extraction of total flavonoid was 15.88 mg/g and antioxidant activity reached 79.53%. The RSM would be recommended as an appropriate model for simultaneous optimization of the UAE conditions for the content of total flavonoid and the antioxidant activity of asparagus of TL.

Supplementation ofBacillus amyloliquefaciensAS385 culture broth powder containing 1-deoxynojirimycin in a high-fat diet altered the gene expressions related to lipid metabolism and insulin signaling in mice epididymal white adipose tissue

Supplementation ofBacillus amyloliquefaciensAS385 culture broth powder in high-fat diet restored adiposity, glucose tolerance and insulin sensitivity in mice.

Novel Antioxidant Peptides Purified from Mulberry (Morus atropurpurea Roxb.) Leaf Protein Hydrolysates with Hemolysis Inhibition Ability and Cellular Antioxidant Activity

Neutrase-hydrolysates hydrolyzed from mulberry leaf proteins were separated by ion exchange chromatography, gel filtration chromatography, and semipreparative reverse-phase HPLC. Purified fractions were analyzed for their radical scavenging activity, hemolysis inhibition ability, and cellular antioxidant activity (CAA). Three new antioxidant peptides, P1 (SVL, 317 Da), P2 (EAVQ, 445 Da), and P3 (RDY, 452 Da), were obtained from the most active HPLC fraction (R1) and identified using UPLC-QTOF-MS. These three peptides were then synthesized, and their antioxidant activities were analyzed. P1 and P2 had no ability to inhibit hemolysis of erythrocytes but did show antioxidant activity on HepG2 cells. P3 showed the highest hemolysis inhibition ability (92%) and CAA value (2204 μM QE/100 g peptide). The Tyr residues at the C-terminal region play an important role in the antioxidant activity in P3. Thus, the natural peptide R1 and synthesized P3 could be used as antioxidants and might be promising components of functional foods.

UPLC-DAD-QTOF/MS Analysis of Flavonoids from 12 Varieties of Korean Mulberry Fruit

Mulberry (Morus alba L.) has been used in East Asia (Korea, China, and Japan) as a medicine because of its various pharmacological effects including the excellent antioxidant properties of its fruit. This study analyzed extracts from 12 varieties of Korean mulberry fruit for flavonoids using ultrahigh-performance liquid chromatography coupled with diode array detection and quadrupole time-of-flight mass spectrometry (UPLC-DAD-QTOF/MS). Six quercetin derivatives were identified by mass spectrometry (MS) based on the [quercetin + H]+ ion (m/z 303), while four kaempferol derivatives were identified based on the [kaempferol + H]+ ion (m/z 287). Two new compounds (morkotin A and morkotin C, quercetin derivatives) were identified for the first time in mulberry fruit. The total flavonoid contents of the mulberry fruits ranged from 35.0 ± 2.3 mg/100 g DW in the Baek Ok Wang variety (white mulberry) to 119.9 ± 7.0 mg/100 g DW in the Dae Shim variety. This study has, for the first time, evaluated the flavonoid chromatographic profiles of 12 varieties of Korean mulberry fruits in a following quali-quantitative approach, which will contribute to improved utilization of these fruits as health foods.