Determination of total flavonoids content in buckwheat and inhibition of α-amylase activity

Diabetes is one of the most difficult chronic diseases to cure in the world,which seriously affects people’s health and quality of life.Flavonoids in buckwheat can regulate blood glucose levels by inhibitingα-amylase activity.Therefore,sweet buckwheat produced in Inner Mongolia was used as the research object,and buckwheat fl avonoids were extracted by ultrasonic-assisted extraction method.Total fl avonoids content was determined by ultraviolet-visible spectrophotometry.With acarbose as the positive control,the inhibition test ofα-amylase was carried out by DNS colorimetry to study the inhibition behavior of fl avonoids onα-amylase activity.The results showed that the extraction process of flavonoids was stable and reliable,and the established method for the determination of flavonoids was simple,accurate and reproducible.The total flavonoids content of buckwheat samples was 2.706 mg/g,buckwheat total fl avonoids extraction solution had an inhibitory eff ect onα-amylase,and its median inhibition concentration(IC_(50))was 38.53 mg/mL.The results of this experiment provide a technical reference for the development and utilization of fl avonoids in Inner Mongolia sweet buckwheat,and provide a theoretical reference for the development and application of flavonoid-rich hypoglycemic food.

Credible and Facile Fluorometric Detection of Soybean Trypsin Inhibitor Activity with a Water-Soluble Poly(diphenylacetylene) Derivative

Herein,a novel method for fl uorometric detection of soybean trypsin inhibitor(SBTI)activity based on a water-soluble poly(diphenylacetylene)derivative was reported.Fluorescence quenching of the polymer via p-nitroaniline,produced from the trypsin-catalyzed decomposition of N-benzoyl-DL-arginine-4-nitroanilide hydrochloride(L-BAPA),was well described using the Stern-Volmer equation.SBTI activity was quantitatively assessed based on changes in the fl uorescence intensity of the polymer.This strategy has several advantages,such as high sensitivity and ease of operation.Moreover,its applicability to other biochemical analyses is promising.

Neuroprotective effects of G9a inhibition through modulation of peroxisome-proliferator activator receptor gamma-dependent pathways by miR-128

Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative stress.Likewise,microRNAs are involved in many biological processes and diseases playing a key role in pathogenesis,especially in multifactorial diseases such as Alzheimer’s disease.Therefore,our aim has been to provide partial insights into the interconnection between G9a,microRNAs,oxidative stress,and neuroinflammation.To better understand the biology of G9a,we compared the global microRNA expression between senescence-accelerated mouse-prone 8(SAMP8)control mice and SAMP8 treated with G9a inhibitor UNC0642.We found a downregulation of miR-128 after a G9a inhibition treatment,which interestingly binds to the 3′untranslated region(3′-UTR)of peroxisome-proliferator activator receptor γ(PPARG)mRNA.Accordingly,Pparg gene expression levels were higher in the SAMP8 group treated with G9a inhibitor than in the SAMP8 control group.We also observed modulation of oxidative stress responses might be mainly driven Pparg after G9a inhibitor.To confirm these antioxidant effects,we treated primary neuron cell cultures with hydrogen peroxide as an oxidative insult.In this setting,treatment with G9a inhibitor increases both cell survival and antioxidant enzymes.Moreover,up-regulation of PPARγby G9a inhibitor could also increase the expression of genes involved in DNA damage responses and apoptosis.In addition,we also described that the PPARγ/AMPK axis partially explains the regulation of autophagy markers expression.Finally,PPARγ/GADD45αpotentially contributes to enhancing synaptic plasticity and neurogenesis after G9a inhibition.Altogether,we propose that pharmacological inhibition of G9a leads to a neuroprotective effect that could be due,at least in part,by the modulation of PPARγ-dependent pathways by miR-128.

Heterointerface Engineering-Induced Oxygen Defects for the Manganese Dissolution Inhibition in Aqueous Zinc Ion Batteries

Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during the electrochemical reaction causes its electrochemical cycling stability to be undesirable.In this work,heterointerface engineering-induced oxygen defects are introduced into heterostructure MnO_(2)(δa-MnO_(2))by in situ electrochemical activation to inhibit manganese dissolution for aqueous zinc ion batteries.Meanwhile,the heterointerface between the disordered amorphous and the crystalline MnO_(2)ofδa-MnO_(2)is decisive for the formation of oxygen defects.And the experimental results indicate that the manganese dissolution ofδa-MnO_(2)is considerably inhibited during the charge/discharge cycle.Theoretical analysis indicates that the oxygen defect regulates the electronic and band structure and the Mn-O bonding state of the electrode material,thereby promoting electron transport kinetics as well as inhibiting Mn dissolution.Consequently,the capacity ofδa-MnO_(2)does not degrade after 100 cycles at a current density of 0.5 Ag^(-1)and also 91%capacity retention after 500cycles at 1 Ag^(-1).This study provides a promising insight into the development of high-performance manganese-based cathode materials through a facile and low-cost strategy.

Total Alkaloid Content, Total Phenolic Content, In Vitro Antioxidant Activity, and Preliminary Antiglycemic Potential of the Methanol Extract from Mozambican Wild Fruits of Vangueria infausta

This study investigated the antioxidant activity and alpha-amylase inhibitory potential of the methanolic extract from Vangueria infausta fruits with the aim of exploring its therapeutic and nutritional applications. Bioactive compounds such as total phenolics (TPC) and total alkaloids (TAC) were analyzed. Antioxidant activity was assessed using the DPPH, ABTS, FRAP, Ferrozine, Phosphomolybdate, and Folin-Ciocalteu methods, while alpha-amylase inhibitory activity was determined using the 3,5-Dinitrosalicylic Acid (DNSA) and 2-chloro-p-nitrophenyl-α-D-maltotrioside (CNPG3) methods. The results revealed significant variations in antioxidant activity across the methods used, with IC50 values ranging from 318.42 to 1255.56 µg/mL. Alpha-amylase inhibition was also significant, with IC50 values ranging from 140.85 to 121.06 µg/mL. The TPC was found to be 95.6 mg of gallic acid equivalent per 100 g of dry powder, and the TAC was 0.188 mg of atropine equivalent per 100 g of dry powder. These findings suggest that Vangueria infausta possesses promising antioxidant and alpha-amylase inhibitory potential, indicating its potential application in antioxidant therapies and in the management of carbohydrate digestion.

Inhibition of α/β-K_6P_2W_(18)O_(62)·10H_2O on the Activity of Mushroom Tyrosinase and Its Antimicrobial Effects

Dawson-type phosphotungstic polyoxometalate α/β-K6P2W18O62·10H2O（P2W18） was synthesized and its inhibitory effect on the mushroom tyrosinase was investigated. It could inhibit diphenolase activity of mushroom tyrosinase as an irreversible inhibitor. When the concentration of the enzyme reached 0.0176 mg/mL, the concentration of P2W18 leading to 50% activity lost（IC50） was 0.05 mmol/L for monophenolase and 0.64 mmol/L for diphenolase. In addition, the antimicrobial activity of P2W18 was evaluated by zone of inhibition test. The results show that P2W18 possesses effective antimicrobial ability against Escherichia coli, Bacillus subtilis, yeast, especially Escherichia coli and yeast.

Studying on Tyrosinase Inhibition Activity of Some Vietnamese Folk Plants Aims to Use in Skin-Whitening Cosmetics

White mulberry Morus alba and jackfruit Artocarpus heterophyllus are two of seven chosen Vietnamese folk plants which showed the highest tyrosinase inhibition activity. Besides, both of them showed antioxidant and antibacterial activities. Especially, the Sulforhodamine B (SRB) assay test result of the root core extract of M. alba figured out its non-toxicity on foreskin fibroblasts.

Inhibition of Carcinogen Induced Activity of γ-glutamyl Transpeptidase by CertainDietary Constituents in Mouse Skin

Cancer chemoprevention, a desirable and important facet of biomedical research, provides a practical approach to identify potentially useful inhibitors of cancer development, and offers an opporiunity to study the mechanism of carcinogenesis. During the recent Past a number of compounds have been tested for their anticarcinogenic potential specially constituents of our diet. The enzyme γglutamyl transpeptidase (GGT) which catalyses the transfer of glutamyl groups of peptides to other peptides and amino acid and has been proposed as a marker of cell proliferation and neoplasia. It also serves as a tool to evaluate the carcinogenic and cocarcinogenic potential of environmental toxicants. In the present investigations, CGT activity induced by careinogenic polycyclic aromatic hydmiarbons, viz. 7, 12-dimethylbenz(a) anthracene (DMBA) and benzo(a) pyrene (BaP) was significantly inhibited by diallylsulfide (DAS) and indole-3-carbnol (I3C) in mouse skin. DAS and 13C are constituents of garlic and cruciferous vegetables respectively. A significant iIthibition in GGT levels was also observed in a strong mitogen (12-o-tetradecanoyl phorbol-13-acetate) induced activity in mouse skin by pretreatment with DAS/13C. Therefore these dietary constituents seem to be strong modifiers of chemically induced carcinogenesis

3-58 Telomerase Activity Inhibition Block DNA Damage Repair

Previous studies in malignant cells have shown that irradiation-induced upregulation of telomerase activity,not only protected damaged telomeres, but also contributed to DNA damage repair by chromosomal healing andincreased resistance to irradiation[1;2].To investigate the radiosensitizing mechanism of telomerase inhibition, the influence of telomerase inhibitor(MST-312) combined with X-ray irradiation on -H2AX foci were determined. As shown in Fig. 1(a), the combinedtreatment resulted in retention of -H2AX nuclear foci and significant decrease of DNA damage repair.

Exploration of larvicidal and adult emergence inhibition activities of Ricinus communis seed extract against three potential mosquito vectors in Kolkata,India

Objective:To determine the larvicidal and adult emergence inhibition activities of castor （Ricinus communis） seed extract against three potential mosquito vectors Anopheles stephensi（An. slephensi）,Culex quinquefasciatus（Cx.quinquefasciatus） and Aedes albopictus（Ae.albopictus） in India.Methods:The R.communis seed extract was tested,employing WHO procedure,against fourth larval instars of the three mosquito species for 24 h and larval mortalities were recorded at various concentrations（2-64μg/mL）:the 24 h LC50 values of the R.communis seed extract were determined following Probit analysis.The larval killing,antipupation and adult emergence inhibition rates of the test extract,using a single concentration of 2μLC50,were studied at different time periods（24-72 h）:the extract toxicity was tested against a fish.Oreochromis niloticus（O.niloticus）.Results:The R.communis seed extract exhibited larvicidal effects with 100%killing activities at concentrations 32-64μg/mL,and with LC50 values 7.10.11.64 and 16.84μg/mL for Cx.quinquefasciatus,An.stephensi and Ae.albopictus larvae,respectively. When the larvae were treated with the extract at a single concentration of 2×LC50,significant differences were observed,compared to control groups,in rate of pupation（P【0.001） as well as in adult formation（P【0.001）.Conclusions:The present findings suggest that the R.communis seed extract provided an excellent potential for controlling An.stephensi,Cx.quinquefasciatus and Ae. albopictus mosquito vectors.

Adult emergence inhibition and adulticidal activities of medicinal plant extracts against Anopheles stephensi Liston

Objective:To determine the adult emergence inhibition（EI） and adulticidal activities of hexane,chloroform,ethyl acetate,and acetone leaves extracts of Anisomeles malabarica（A. malabarica）,Euphorbia hirta（E,hirta）,Ocimum basilicum（0.basilicum）,Ricinus communis（R. communis）,Solanum trilobatum（S.trilobatum）,Tridax procumbens（T.procumbens） and seeds of Gloriosa superba（G.superba） against Anopheles stephensi（An,stephensi）.Methods:The EI and adulticidal trials were carried out according to World Health Organization（WHO） procedures with slight modifications.The extracts were diluted in dimethyl sulphoxide in order to prepare a serial dilution of test dosages（15.625,31.25,62.5,125,250,500 and 1 000μg/mL）.Five duplicate trials were carried out for every sample concentration,and for each trial a negative control was included and the mortality was determined after 24 h of exposure.Results:The highest EI activity was found in ethyl acetate extracts of A malabarica,chloroform extracts of O.basilicum, S.trilobatum,acetone of extract of R.communis,T.procumbens,and seed extract of G.superba with EI50 values 143.12,119.82.157.87,139.39,111.19,and 134.85μg/mL,and the effective adulticidal activity was observed in chloroform,acetone extracts of G.superba,T.procumbens,R. communis,S.trilobatum and ethyl acetate extract of 0.basilicum with LD50 values 120.17,108.77, 127.22,163.11,118.27,and 93.02μg/mL,respectively.Chi-square value was significant at P【0.05 level.Conclusions:These results should encourage further efforts to investigate the compounds that might possess good EI and adulticidal properties when isolated in pure form.

Synthesis, Characterization and Biological Activity Evaluation of Schiff Bases Derived from 1,8-Diaminonaphtalène

The compounds have been synthesized and characterized by routine MS, IR and NMR spectrometry methods. The compounds are all active on bacterial strains with the exception of Salmonella typhimirium, with a MIC value of 7.5 mg/mL. They show a percentage of anti-radical activity of 75.476 ± 5.070 for the compound DAN-S and of 68.142 ± 6.539 for the compound DAN-OV. The compounds are sensitive to the two champions used. DAN-S compound is then the most active.

Inhibitory activity of an extract from a marine bacterium Halomonas sp.HSB07 against the red-tide microalga Gymnodinium sp.(Pyrrophyta)

In recent years,red tides occurred frequently in coastal areas worldwide.Various methods based on the use of clay,copper sulfate,and bacteria have been successful in controlling red tides to some extent.As a new defensive agent,marine microorganisms are important sources of compounds with potent inhibitory bioactivities against red-tide microalgae,such as Gymnodinium sp.(Pyrrophyta).In this study,we isolated a marine bacterium,HSB07,from seawater collected from Hongsha Bay,Sanya,South China Sea.Based on its 16S rRNA gene sequence and biochemical characteristics,the isolated strain HSB07 was identified as a member of the genus Halomonas.A crude ethyl acetate extract of strain HSB07 showed moderate inhibition activity against Gymnodinium sp.in a bioactive prescreening experiment.The extract was further separated into fractions A,B,and C by silica gel column chromatography.Fractions B and C showed strong inhibition activities against Gymnodinium.This is the first report of inhibitory activity of secondary metabolites of a Halomonas bacterium against a red-tide-causing microalga.

Synthesis,algal inhibition activities and QSAR studies of novel gramine compounds containing ester functional groups

2,5,6-Tribromo-l-methylgramine （TBG）, isolated from bryozoan Zoobotryon pellucidum was shown to be very efficient in preventing recruitment of larval settlement. In order to improve the compatibility of TBG and its analogues with other ingredients in antifouling paints, structural modification of TBG was focused mainly on halogen substitution and N-substitution. Two halogen-substitute gramines and their derivatives which contain ester functional groups at N-position of gramines were synthesized. Algal inhibition activities of the synthesized compounds against algae Nitzschia cIosterium were evaluated and the Median Effective Concentration （EC50） range was 1.06-6.74 lag ml^-1. Compounds that had a long chain ester group exhibited extremely high antifouling activity. Quantitive Structure Activity Relationship （QSAR） studies with multiple linear regression analysis were applied to fred correlation between different calculated molecular descriptors and biological activity of the synthesized compounds. The results show that the toxicity （log （I/EC50）） is correlated well with the partition coefficient log P. Thus, these products have potential function as antifouling agents.

Inhibition of Micro RNA 219 Expression Protects Synaptic Plasticity via Activating NMDAR1, Ca MKIIγ,and p-CREB after Microwave Radiation

In recent decades,the potential health hazards of microwave exposure have been attracting increasing attention.Our previous studies have demonstrated that microwave exposure impaired learning and memory in experimental animal models[1,2].

Enzymes inhibitory property,antioxidant activity and phenolics profile of raw and roasted red sorghum grains in vitro

Whole grain cereals are important dietary sources for management of metabolic diseases due to the bioactive components they contain.Hence,this study investigated enzymes(pancreatic lipase,-amylase,-glucosidase,xanthine oxidase and angiotensin 1-converting enzyme)inhibitory property,antioxidant activity and phenolics profile of raw and roasted red sorghum(Sorghum bicolor)grains in vitro.Extracts of flours of raw and roasted(150◦C and 180◦C,for 20 min)grains were assayed for enzymes inhibitory and antioxidant activities using spectrophotometric methods;while their phenolic constituents were characterized using HPLC-DAD.The raw grains exhibited strong enzymes inhibitory and antioxidant activities,and contained phenolic acids(gallic,chlorogenic,caffeic,ellagic and p-coumaric acids)and flavonoids(quercetin,luteolin and apigenin).However,whereas the enzymes inhibitory activity and levels of the phenolic compounds in the grains decreased significantly(p<0.05)with increasing roasting temperature,the antioxidant activity increased.Hence,roasting at high temperature may not be recommended for the optimum retention of the enzymes inhibitory property and phenolic compounds of red sorghum grains.

In Vitro Evaluation of the Antifungal Activity of Essential Oils of Thymus vulgaris and Cymbopogon citratus on Some Strains of Sclerotinia sclerotiorum, Agent Responsible for White Rot of Beans

The present work was aimed to the study of the antifungal activity of essential oils of two aromatic plants against three strains of Sclerotinia sclerotiorum responsible for white rot of bean. The two essential oils (EO) of the studied plants: Thymus vulgaris (HET) and Cymbopogon citratrus (HEC), used at different concentrations: C1 (0.75 ml/ml), C2 (1.5 ml/ml) and C3 (3 ml/ml) presented significant inhibitory activities on the three tested fungal strains namely Bia 1, Bia 2, and Njo 2. Two control treatments (T-: containing no antifungal substance and T+: synthetic fungicide) were also used. The antifungal activity here is related to the inhibition of mycelial growth especially with high concentrations of essential oils. Thus, against S. sclerotiorum, HET showed the highest activity comparable to that of T+ (100% inhibition) at all concentrations on the Bia 1 and Bia 2 strains and at concentration C3 on the Njo 2 strain compared to that of HEC, which certainly inhibited the mycelial growth of the different strains considerably (with a maximum of 78.15% on the Njo 2 strain) but not completely. According to their sensitivity, the Bia 2 strain showed a higher sensitivity to essential oils than the others while the Njo 2 strain was more aggressive. On the basis of MIC50 and MIC90 obtained on the Njo 2 strain, the HET turns out to be the most efficient with respective lower values of (1.73 and 23.34 ml/ml) against (4.76 and 26.03 ml/ml) for the HEC. These EO could thus be exploited as biodegradable antifungal substances, likely to control white rot of bean.

Response of soil catalase activity to chromium contamination

The impact of chromium（Ⅲ） and （Ⅵ） forms on soil catalase activity was presented. The Orthic Podzol, Haplic Phaeozem and Mollic Gleysol from different depths were used in the experiment. The soil samples were amended with solution of Cr（Ⅲ） using CrCl3, and with Cr（Ⅵ） using K2Cr2O7 in the concentration range from 0 to 20 mg/kg, whereas the samples without the addition of chromium served as control. Catalase activity was assayed by one of the commonly used spectrophotometric methods. As it was demonstrated in the experiment, both Cr（Ⅲ） and Cr（Ⅵ） have an ability to reduce soil catalase activity. A chromium dosage of 20 mg/kg caused the inhibition of catalase activity and the corresponding contamination levels ranged from 75% to 92% for Cr（Ⅲ） and 68% to 76% for Cr（Ⅵ）, with relation to the control. Catalase activity reached maximum in the soil material from surface layers （0-25 cm）, typically characterized by the highest content of organic matter creating favorable conditions for microorganisms.

Antioxidant and antibacterial activity of different parts of Leucas aspera

Objective:To evaluate antioxidant,antimicrobial and cytotoxic activity of different parts(root, flower,leaf and stem)of Leucas aspera(L.aspera)(Labiatae).Methods:Different parts of L.aspera were extracted with 80%(v/v)methanol.The methanol extracts were subjected to antioxidant, antimicrobial and brine shrimp lethality assay.Results:All the extracts showed moderate to potent antioxidant activity,among which the root extract demonstrated the strongest antioxidant activity with the IC_(50)value of 6.552μg/mL.Methanol extract of root possessed antioxidant activity near the range of vitamin E and thus could be a potential rich source of natural antioxidant.In case of antimicrobial screening,crude extracts of root,flower,leaf and stem showed notable antibacterial activity against tested microorganisms.The root extract showed the highest mean zone of inhibition ranging from 9.0-11.0 mm against tested microorganisms,at a concentration of 100 mg/mL.In the brine shrimp lethality bioassay,it was evident that the methanol root extract did not show significant toxicity.The LC_(50)value for 12 h and 24 h observation was 2.890 mg/mL and 1.417 mg/mL,respectively.Conclusions:The present finding suggests that the methanol root extract of L.aspera could be developed as pharmaceutical products.

Combined antibacterial activity of stingless bee(Apis mellipodae)honey and garlic(Allium sativum)extracts against standard and clinical pathogenic bacteria

Objective:To investigate the synergic antibacterial activity of garlic and tazma honey against standard and clinical pathogenic bacteria.Methods:Antimicrobial activity of tazma honey,garlic and mixture of them against pathogenic bacteria were determined.Chloramphenicol and water were used as positive and negative controls,respectively.Minimum inhibitory concentration(MIC)and minimum bactericidal concentration of antimicrobial samples were determined using standard methods.Results:Inhibition zone of mixture of garlic and tazma honey against all tested pathogens was significantly(P≤0.05)greater than garlic and tazma honey alone.The diameter zone of inhibition ranged from(18±1)to(35±1)mm for mixture of garlic and tazma honey,(12±1)to(20±1)nun for tazma honey and(14±1)to(22±1)mm for garlic as compared with(10±1)to(30±1)mm for chloramphenicol.The combination of garlic and tazma honey(30-35 mm)was more significantly(P≤0.05)effective against Salmonella(NCTC 8385),Staphylococcus aureus(ATCC 25923),Lyesria moncytogenes(ATCC 19116)and Streptococcus pneumonia(ATCC 63).Results also showed considerable antimicrobial activity of garlic and tazma honey.MIC of mixture of garlic and tazma honey at 6.25%against total test bacteria was 88.9%.MIC of mixture of garlic and tazma honey at6.25%against Gram positive and negative were 100%and 83.33%,respectively.The bactericidal activities of garlic,tazma honey,and mixture of garlic and tazma honey against all pathogenic bacteria at 6.25%concentration were 66.6%,55.6%and 55.6%,respectively.Conclusions:This finding strongly supports the claim of the local community to use the combination of tazma honey and garlic for the treatment of different pathogenic bacterial infections.Therefore,garlic in combination with tazma honey can serve as an alternative natural antimicrobial drug for the treatment of pathogenic bacterial infections.Further in vivo study is recommended to come up with a comprehensive conclusion.