Dispersal patterns exhibited by group-living animals play an important role in individual reproductive success and survival, as well as population and social dynamics (Greenwood, 1980; Isbell and van Vuren, 1996; Kap...Dispersal patterns exhibited by group-living animals play an important role in individual reproductive success and survival, as well as population and social dynamics (Greenwood, 1980; Isbell and van Vuren, 1996; Kappeler and van Schaik, 2002). Dispersing individuals may emigrate voluntarily, or they may be forcibly evicted by other individuals (Pusey and Packer, 1987; Clobert et al. , 2001 ). One cause of individual dispersal is when an extra-group male compels another male to leave a group of females. This phenomenon has been well documented in primates, especially Old World monkey species ( e.g. Colobus vellerosus : Saj and Sicotte, 2005 ; Erythrocebus patas : Ohsawa, 2003 ; Macaca fascicularis : van Noordwiik and van Schaik, 2001).展开更多
By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were ...By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.展开更多
In the past decade there has been a profusion of studies highlighting covariation between individual differences in stress physiology and behavioural profiles, here called personalities. Such individual differences in...In the past decade there has been a profusion of studies highlighting covariation between individual differences in stress physiology and behavioural profiles, here called personalities. Such individual differences in ways of coping with stress are relevant both in biomedicine, since different personalities may experience a different stress and disease vulnerability, and in behavioural ecology, since their adaptive value and evolutionary maintenance are the subject of debate. However, the precise way in which individual stress differences and personalities are linked is unclear. Here we provide an updated overview of this covariation across different species and taxa, consider its functional significance and present working hypotheses for how behavioural and physiological responses to stress might be causally linked, affecting life-history traits such as dispersal and life-span [Current Zoology 56 (6): 728-740, 2010].展开更多
Inducing expression and the reaction characteristic of nitrile hydratase (NHase) from Rhodococcus sp. SHZ-1 were investigated. The results showed that the expression of NHase was greatly enhanced with the cooperatio...Inducing expression and the reaction characteristic of nitrile hydratase (NHase) from Rhodococcus sp. SHZ-1 were investigated. The results showed that the expression of NHase was greatly enhanced with the cooperation of acrylonitrile and ammonium chloride as inducer in the medium and the specific activity of NHase was increased of 44%. Then the temperature, pH, concentration of acrylonitrile and acrylamide were evaluated, which affected the activity and reaction characteristic of NHase. It was found that the temperature and concentration of acrylarnide were the most important factors for the catalyzation of NHase. The optimal catalysis temperature of NHase from Rhodococcus sp. SHZ-1 was 30℃, and the activation energy of the hydration of NHase was 90.2kJ·mol^-1 in the temperature range from 5℃ to 30℃. Kmof NHase was 0.095mol·L^-1 using acrylonitrile(AN) as substrate, and NHase activity was inhibited seriously when acrylonitrile concentration was up to 40g·L^-1, the substrate inhibition constant Ki is 0.283mol·L^-1. Moreover, the NHase from Rhodococcus sp. SHZ-1 had very strong tolerance to acrylamide, in which the final concentration of acrylamide reached to 642g·L^-1 and the residual activity of NHase still maintained 8.6% of the initial enzyme activity.展开更多
It has been documented that social isolation imparts deleterious effects on gregarious rodents species, but caging in group imparts such effects on solitary rodents. This study was attempted at examining how kinship t...It has been documented that social isolation imparts deleterious effects on gregarious rodents species, but caging in group imparts such effects on solitary rodents. This study was attempted at examining how kinship to affect body weight, behavioral interaction, mate choice and fitness when we caged male and female rat-like hamsters Tscheskia triton in pair, a solitary species. We found that females paired with nonsibling males became heavier than the females paired with sibling males, but both agonistic and amicable behavior between paired males and females did not differ between sibling and nonsibling groups. This indicated that kinship might reduce females' obesity in response to forced cohabitation, and dissociation might exist between physiological and behavioral responses. Furthermore, binary choice tests revealed that social familiarity between either siblings or nonsiblings decreased their investigating time spent in opposite sex conspeeifie of cage mates and/or their scents as compared with those of nonmates, suggesting effects of social association on mate and kin selection of the hamsters. On the other side, both females and males caged in pair with siblings show a preference between unfamiliar siblings or their scents and the counterparts of nonsiblings after two month separation, indicating that the kin recognition of the hamsters might also rely on phenotype matching. In addition, cohabitation (or permanent presence of fathers) elicited a lower survival of pups in nonsibling pairs than sibling pairs, but did not affect litter size, suggesting that kinship affects fitness when housing male and female ratlike hamsters together. Therefore, inbreeding might be adapted for rare and endangered animals.展开更多
The present study was conducted to evaluate the feasibility of replacing fish meal(FM) with bioactive peptides(BPs) in diet of white shrimp(Litopenaeus vannamei). The changes in growth performance, body composition, n...The present study was conducted to evaluate the feasibility of replacing fish meal(FM) with bioactive peptides(BPs) in diet of white shrimp(Litopenaeus vannamei). The changes in growth performance, body composition, non-specific immunity, and water quality were examined after the shrimp were fed four diets, in which 0%(control), 33.3%, 66.7% and 100% of FM was replaced by BPs, respectively. The groups were designated as Con, 1/3BPs, 2/3BPs, and 3/3BPs. A total of 720 shrimp with an initial body weight of 1.46 ± 0.78 g were fed the experimental diets for 56 days. The results revealed that: 1) the weight gain rate(WGR) in 1/3BPs, 2/3BPs, and 3/3BPs was significantly higher than that in Con(P < 0.05), while no significant difference was found on survival rate and feed conversion ratio(FCR); 2) the whole-body crude protein(CP) and crude lipids(CL) were significantly different among groups, while there was no significant difference between crude ash and phosphorus contents; 3) the levels of acid phosphatase(ACP), lysozyme(LZM), superoxide dismutase(SOD), phenol oxidase(PO) and bactericidal activity increased significantly with the inclusion of BPs; 4) in terms of water quality, no significant difference was found in p H and dissolved oxygen among diets during the whole experimental period. Moreover, even though nitrite and ammonium levels tended to increase with time, there was no significant difference among groups. The results indicated that BPs is an applicable alternative of protein source, which can substitute FM in the diets of L. vannamei; it is able to effectively promote growth performance and improve immunity. Moreover, BPs in the diets had no negative impact on water quality.展开更多
The purpose of this research was to study learning retention in undergraduate biology students on the topic of enzyme properties by using simple enzyme activity from vegetables and fruits. A hands-on practical was dev...The purpose of this research was to study learning retention in undergraduate biology students on the topic of enzyme properties by using simple enzyme activity from vegetables and fruits. A hands-on practical was developed to simplify detection of enzyme activity of amylase, protease and lipase on starch agar, dry whole milk agar, and trihutyrin agar, respectively. The subjects of the study were 24 senior undergraduates who studied in the Program of General Science, Faculty of Science, Srinakharinwirot University, Bangkok, in three semesters during 2007 - 2008. The basic concepts of enzymes, e.g., substrate specificity, how to detect enzymes and optimal enzyme conditions, were taught before the practical. The first enzyme, protease, was used in the second semester of 2007, and then changed to be lipase and protease in the first and second semesters of 2008, respectively. Ten open-ended questions were used to assess students in all semesters. In agreement with the constructivist learning model, it was demonstrated that students had learning retention and applied their prior knowledge to other enzyme experiments.展开更多
The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the...The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the substrate of integrated vertical-flow constructed wetland and mainly in the 0-10 cm top layer where the activity ofdehydrogenase of the biofilm was also higher than that of other layers. The water quality could also affect the activity of the biofilm, for the TF(1,3,5-Triphenylformazan) amount reduced by the biofim incubated in water of the higher eutrophication was larger, too. The PCP (pentachlorophenol) removal rate by the substrate with biofilm was 1.5 times that without biofilm. In total, the biofilm of the down-flow chamber appeared larger biomass, higher dehydrogenase activity and stronger degradation capability of organic contamination than that in up-flow chamber and it was the major place for removal of the organic matters in waste water.展开更多
Angiotensin (Ang)-(1-7) is recognized as a new bioactive peptide in renin-angiotensin system (RAS). Ang-(1-7) is a counter-regulatory mediator of Ang-II which appears to be protective against cardiovascular di...Angiotensin (Ang)-(1-7) is recognized as a new bioactive peptide in renin-angiotensin system (RAS). Ang-(1-7) is a counter-regulatory mediator of Ang-II which appears to be protective against cardiovascular disease. Recent studies have found that Ang-(1-7) played an important role in reducing smooth muscle cell proliferation and migration, improving endothelial function and regulating lipid metabolism, leading to inhibition of atherosclerotic lesions and increase of plaque stability. Although clinical application of Ang-(1-7) is restricted due to its pharmacokinetic properties, identification of stabilized compounds, including more stable analogues and specific delivery compounds, has enabled clinical application of Ang-(1-7). In this review, we discussed recent findings concerning the biological role of Ang-(1-7) and related mechanism during atherosclerosis development. In addition, we highlighted the perspective to develop therapeutic strategies using Ang-(1-7) to treat atherosclerosis.展开更多
The inclusion of atrazine with 2-hydroxypropyl-β-cyclodextrin(HPCD) was synthesized by ultrasonic method, and it was characterized by UV, XRD and 1H NMR. The solubility in water and the bioactivity of the inclusion w...The inclusion of atrazine with 2-hydroxypropyl-β-cyclodextrin(HPCD) was synthesized by ultrasonic method, and it was characterized by UV, XRD and 1H NMR. The solubility in water and the bioactivity of the inclusion were also studied here. The results indicated that the UV maximum absorption wavelength of the inclusion remained at 223 nm, while its intensity decreased. The XRD peaks of atrazine disappeared, weakened and shifted in the inclusion, and the chemical shift of H-3 and H-5 of cyclodextrin inner cavity led to the upfield. The characterization data showed that the atrazine-HPCD inclusion had already formed. At the same time, the solubility of the atrazineHPCD inclusion in water became 20.08 times as that of atrazine. Moreover, the atrazine-HPCD inclusion had better herbicidal activity. When the concentration of the inclusion was 6.5 mg/mL, the inhibition ratios of the inclusion to taproot length, taproot fresh weight, sprout length and sprout fresh weight of barnyard grass were 66.96%, 57.22%, 70% and 57.53%, respectively, which were all higher than those of atrazine.展开更多
Meat and meat products are extremely perishable, so special care and handling must be exercised during slaughtering operation. Moreover, due to its high nutritive value, deterioration set in immediately after slaughte...Meat and meat products are extremely perishable, so special care and handling must be exercised during slaughtering operation. Moreover, due to its high nutritive value, deterioration set in immediately after slaughtered, therefore it is necessary to preserved meat, using simple techniques. One of such method of preservation is drying method to produced Intermediate Moisture Meat (IMM). The quality attributes and microbiological status of Kundi, a West African dried meat product (IMM) were studied over three months of storage period by comparing commercial products and laboratory Kundi products. Chemical and minerals composition and microbiological counts were reported. Moisture and water activity results indicated that the experimental Kundi was sufficiently dried to minimize microbial growth. Fat oxidation levels measured by free fatty acids (FFA, %) on extracted fats were unacceptably high for the commercial Kundi (2.64%), which may be a reflection of the oil used in spraying the products. Processing of Kundi, appears to have relative higher amounts of minerals than fresh meat but their relative solubility were lower. Aflatoxin levels far exceeded established safe limits for commercial samples while laboratory samples fell under the safe limits, resulting from the mould growth in each product, with laboratory samples having lower growth than commercial samples.展开更多
The some physical and chemical properties values ofpepino fruit were determined. The mineral elements (AI, B, Ca, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Se and Zn) of fruit were analysed by Inductively Coupled Plasma Ato...The some physical and chemical properties values ofpepino fruit were determined. The mineral elements (AI, B, Ca, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Se and Zn) of fruit were analysed by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Organic acid contents were analysed via HPLC equipped Ca (3,256.96 mg/kg), K (43,465.60 mg/kg), P (7,907.32 mg/kg) Na (1,496.13 mg/kg) and Mg (2,541.12 mg/kg) were established as major minerals in fruits. These results show that pepino fruit may be useful for the evaluation of dietary information in important food crops.展开更多
The white mulberry (Morus alba L.) had been forgotten in Europe or known only as a plant associated with breeding of mulberry silkworms (Bombyx mori L.). The initial studies have shown great potential of this plan...The white mulberry (Morus alba L.) had been forgotten in Europe or known only as a plant associated with breeding of mulberry silkworms (Bombyx mori L.). The initial studies have shown great potential of this plant in energy, food and pharmaceutical industries. The leaves and fruits contain very valuable bioactive substances, which may be used in health care. Antioxidants of plant origin include flavonoids and vitamin C (ascorbic acid), and these substances are present in high amounts in anatomical parts of white mulberry. It has also been reported on the medicinal properties of this plant and its use in preventing diseases, such as atherosclerosis, diabetes, obesity and cancer. The food industry increasingly uses the white mulberry in food to provide human organism with precious bioactive substances. Functional food, due to the presence in its composition of valuable components, is beneficial to human health. What is more, very fast growth of mulberry causes that biomass of the plant may be used as biofuel or energy plant. The aim of this paper is to present the possibility of using the white mulberry as a raw material for functional foods and as an energy plant.展开更多
Tetronate antibiotics, a growing family of natural products featuring a characteristic tetronic acid moiety, are of importance and of particular interest for their typical structures, especially the spirotetronate str...Tetronate antibiotics, a growing family of natural products featuring a characteristic tetronic acid moiety, are of importance and of particular interest for their typical structures, especially the spirotetronate structure, and corresponding versatile biolog- ical activities. Considerable efforts have persistently performed since the first tetronate was isolated, to elucidate the biosyn- thesis of natural tetronate products, by isotope-labeled feeding experiments, genetical characterization of biosynthetic gene clusters, and biochemical reconstitution of key enzymatic catalyzed reactions. Accordingly, the biosynthesis of spirotetronates has been gradually determined, including biosynthesis of a polyketide-derived backbone for spirotetronate aglycone, incorpo- ration of a glycerol-derived three-carbon unit into tetronic acid moiety, formation of mature aglycone via Diels-AIder-like re- action, and decorations of aglycone with various deoxysugar moieties. In this paper, the biosynthetic investigations of natural tetronates are well documented and a common biosynthetic route for this group of natural products is summarized accordingly.展开更多
The strained cyclopropane and/or cyclobutane subunits occurred in many complex natural products including terpenoids, steroids and alkaloids. Natural products with cyclopropane and/or cyclobutane motifs not only furni...The strained cyclopropane and/or cyclobutane subunits occurred in many complex natural products including terpenoids, steroids and alkaloids. Natural products with cyclopropane and/or cyclobutane motifs not only furnished fascinating structures, but also exhibited versatile biological activities, such as cytotoxic, anti-HIM antimicrobial, antiviral, and immunosuppressive effects. This review covered a large array of structurally unique natural products with strained cyclopropane and/or cyclobutane motifs and summarized their structural features, distributions, biological activities, as well as biogenetic considerations.展开更多
Investigating the effects of residue chemical composition on soil labile organic carbon (LOC) will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil w...Investigating the effects of residue chemical composition on soil labile organic carbon (LOC) will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil water content on soil LOC fractions and microbial properties were investigated in a laboratory incubation experiment. Maize shoot and root residues were incorporated into soil at 40% and 70% field capacity. The soils were incubated at 20 ℃ for 150 d and destructive sampling was conducted after 15, 75, and 150 d. Respiration, dissolved organic carbon (DOC), hot-water extractable organic carbon (HEOC), and microbial biomass carbon (MBC) were recorded, along with cellulase and β-glucosidase activities and community-level physiological profiles. The results showed that the cumulative respiration was lower in root-amended soils than in shoot-amended soils, indicating that root amendment may be beneficial to C retention in soil. No significant differences in the contents of DOG, HEOC and MBC, enzyme activities, and microbial functional diversity were observed between shoot- and root-amended soils. The high soil water content treatment significantly increased the cumulative respiration, DOC and HEOC contents, and enzyme activities compared to the low soil water content treatment. However, the soil water content treatments had little influence on the MBC content and microbial functional diversity. There were significantly positive correlations between LOC fractions and soil microbial properties. These results indicated that the chemical composition of maize residues had little influence on the DOC, HEOC, and MBC contents, enzyme activities, and microbial functional diversity, while soil water content could significantly influence DOC and HEOC contents and enzyme activities.展开更多
Naturally occurring secolignans have drawn the considerable attention because of their novel structures and diverse biological activities.In recent years,various natural secolignans with extensive bioactivities have b...Naturally occurring secolignans have drawn the considerable attention because of their novel structures and diverse biological activities.In recent years,various natural secolignans with extensive bioactivities have been reported in the literatures.In the present review,we summarized all the available information regarding the biosynthesis,distributions,separation methods,chemical structures,spectral characteristics,and biological activities of natural secolignans,and provided some valuable new insights for the further study.展开更多
基金funded by Natural Science Foundation of China(No.30770375,No.30570312,No.30630016)Cosmo Oil Eco Card Fund of Japan(2005-2010)Northwest University Doctorate Dissertation of Excellence Funds(07YYB06)
文摘Dispersal patterns exhibited by group-living animals play an important role in individual reproductive success and survival, as well as population and social dynamics (Greenwood, 1980; Isbell and van Vuren, 1996; Kappeler and van Schaik, 2002). Dispersing individuals may emigrate voluntarily, or they may be forcibly evicted by other individuals (Pusey and Packer, 1987; Clobert et al. , 2001 ). One cause of individual dispersal is when an extra-group male compels another male to leave a group of females. This phenomenon has been well documented in primates, especially Old World monkey species ( e.g. Colobus vellerosus : Saj and Sicotte, 2005 ; Erythrocebus patas : Ohsawa, 2003 ; Macaca fascicularis : van Noordwiik and van Schaik, 2001).
基金Supported by Natural Science Foundation of Shanghai(10ZR1400300 )Central University Special Foundation of Basic Research and Operating expenses+1 种基金Creative Group Foundation of the National Natural Science Foundation of China (50721006)Key Discipline construction Project of Shanghai (B604)~~
文摘By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.
文摘In the past decade there has been a profusion of studies highlighting covariation between individual differences in stress physiology and behavioural profiles, here called personalities. Such individual differences in ways of coping with stress are relevant both in biomedicine, since different personalities may experience a different stress and disease vulnerability, and in behavioural ecology, since their adaptive value and evolutionary maintenance are the subject of debate. However, the precise way in which individual stress differences and personalities are linked is unclear. Here we provide an updated overview of this covariation across different species and taxa, consider its functional significance and present working hypotheses for how behavioural and physiological responses to stress might be causally linked, affecting life-history traits such as dispersal and life-span [Current Zoology 56 (6): 728-740, 2010].
基金Supported by the National Natural Science Foundation of China (No.20466002), the Program for New Century Excellent Talents in University (NCET-04-089) and the Key Research Projects in the Uygur Autonomous Region of Xinjiang (No.200332109).
文摘Inducing expression and the reaction characteristic of nitrile hydratase (NHase) from Rhodococcus sp. SHZ-1 were investigated. The results showed that the expression of NHase was greatly enhanced with the cooperation of acrylonitrile and ammonium chloride as inducer in the medium and the specific activity of NHase was increased of 44%. Then the temperature, pH, concentration of acrylonitrile and acrylamide were evaluated, which affected the activity and reaction characteristic of NHase. It was found that the temperature and concentration of acrylarnide were the most important factors for the catalyzation of NHase. The optimal catalysis temperature of NHase from Rhodococcus sp. SHZ-1 was 30℃, and the activation energy of the hydration of NHase was 90.2kJ·mol^-1 in the temperature range from 5℃ to 30℃. Kmof NHase was 0.095mol·L^-1 using acrylonitrile(AN) as substrate, and NHase activity was inhibited seriously when acrylonitrile concentration was up to 40g·L^-1, the substrate inhibition constant Ki is 0.283mol·L^-1. Moreover, the NHase from Rhodococcus sp. SHZ-1 had very strong tolerance to acrylamide, in which the final concentration of acrylamide reached to 642g·L^-1 and the residual activity of NHase still maintained 8.6% of the initial enzyme activity.
基金supported by the grants from International Partnership Project of CAS Innovative Researches(CXTDS2005-4)Ministry of Science and Technology(2005BA529A05)Chinese NSF(30670268)
文摘It has been documented that social isolation imparts deleterious effects on gregarious rodents species, but caging in group imparts such effects on solitary rodents. This study was attempted at examining how kinship to affect body weight, behavioral interaction, mate choice and fitness when we caged male and female rat-like hamsters Tscheskia triton in pair, a solitary species. We found that females paired with nonsibling males became heavier than the females paired with sibling males, but both agonistic and amicable behavior between paired males and females did not differ between sibling and nonsibling groups. This indicated that kinship might reduce females' obesity in response to forced cohabitation, and dissociation might exist between physiological and behavioral responses. Furthermore, binary choice tests revealed that social familiarity between either siblings or nonsiblings decreased their investigating time spent in opposite sex conspeeifie of cage mates and/or their scents as compared with those of nonmates, suggesting effects of social association on mate and kin selection of the hamsters. On the other side, both females and males caged in pair with siblings show a preference between unfamiliar siblings or their scents and the counterparts of nonsiblings after two month separation, indicating that the kin recognition of the hamsters might also rely on phenotype matching. In addition, cohabitation (or permanent presence of fathers) elicited a lower survival of pups in nonsibling pairs than sibling pairs, but did not affect litter size, suggesting that kinship affects fitness when housing male and female ratlike hamsters together. Therefore, inbreeding might be adapted for rare and endangered animals.
基金supported by the Science-Technology Supporting Project of the National Twelfth Five-YearPlan of China (No. 2012BAD25B01)
文摘The present study was conducted to evaluate the feasibility of replacing fish meal(FM) with bioactive peptides(BPs) in diet of white shrimp(Litopenaeus vannamei). The changes in growth performance, body composition, non-specific immunity, and water quality were examined after the shrimp were fed four diets, in which 0%(control), 33.3%, 66.7% and 100% of FM was replaced by BPs, respectively. The groups were designated as Con, 1/3BPs, 2/3BPs, and 3/3BPs. A total of 720 shrimp with an initial body weight of 1.46 ± 0.78 g were fed the experimental diets for 56 days. The results revealed that: 1) the weight gain rate(WGR) in 1/3BPs, 2/3BPs, and 3/3BPs was significantly higher than that in Con(P < 0.05), while no significant difference was found on survival rate and feed conversion ratio(FCR); 2) the whole-body crude protein(CP) and crude lipids(CL) were significantly different among groups, while there was no significant difference between crude ash and phosphorus contents; 3) the levels of acid phosphatase(ACP), lysozyme(LZM), superoxide dismutase(SOD), phenol oxidase(PO) and bactericidal activity increased significantly with the inclusion of BPs; 4) in terms of water quality, no significant difference was found in p H and dissolved oxygen among diets during the whole experimental period. Moreover, even though nitrite and ammonium levels tended to increase with time, there was no significant difference among groups. The results indicated that BPs is an applicable alternative of protein source, which can substitute FM in the diets of L. vannamei; it is able to effectively promote growth performance and improve immunity. Moreover, BPs in the diets had no negative impact on water quality.
文摘The purpose of this research was to study learning retention in undergraduate biology students on the topic of enzyme properties by using simple enzyme activity from vegetables and fruits. A hands-on practical was developed to simplify detection of enzyme activity of amylase, protease and lipase on starch agar, dry whole milk agar, and trihutyrin agar, respectively. The subjects of the study were 24 senior undergraduates who studied in the Program of General Science, Faculty of Science, Srinakharinwirot University, Bangkok, in three semesters during 2007 - 2008. The basic concepts of enzymes, e.g., substrate specificity, how to detect enzymes and optimal enzyme conditions, were taught before the practical. The first enzyme, protease, was used in the second semester of 2007, and then changed to be lipase and protease in the first and second semesters of 2008, respectively. Ten open-ended questions were used to assess students in all semesters. In agreement with the constructivist learning model, it was demonstrated that students had learning retention and applied their prior knowledge to other enzyme experiments.
文摘The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the substrate of integrated vertical-flow constructed wetland and mainly in the 0-10 cm top layer where the activity ofdehydrogenase of the biofilm was also higher than that of other layers. The water quality could also affect the activity of the biofilm, for the TF(1,3,5-Triphenylformazan) amount reduced by the biofim incubated in water of the higher eutrophication was larger, too. The PCP (pentachlorophenol) removal rate by the substrate with biofilm was 1.5 times that without biofilm. In total, the biofilm of the down-flow chamber appeared larger biomass, higher dehydrogenase activity and stronger degradation capability of organic contamination than that in up-flow chamber and it was the major place for removal of the organic matters in waste water.
基金This work was supported by National Natural Science Foundation of China (NSFC) (No. 81400265 and No. 81270274), and Peking University People's Hospital Research and Development funds (RDB2014-16).
文摘Angiotensin (Ang)-(1-7) is recognized as a new bioactive peptide in renin-angiotensin system (RAS). Ang-(1-7) is a counter-regulatory mediator of Ang-II which appears to be protective against cardiovascular disease. Recent studies have found that Ang-(1-7) played an important role in reducing smooth muscle cell proliferation and migration, improving endothelial function and regulating lipid metabolism, leading to inhibition of atherosclerotic lesions and increase of plaque stability. Although clinical application of Ang-(1-7) is restricted due to its pharmacokinetic properties, identification of stabilized compounds, including more stable analogues and specific delivery compounds, has enabled clinical application of Ang-(1-7). In this review, we discussed recent findings concerning the biological role of Ang-(1-7) and related mechanism during atherosclerosis development. In addition, we highlighted the perspective to develop therapeutic strategies using Ang-(1-7) to treat atherosclerosis.
基金Supported by the National Natural Science Foundation of China(No.31370709)
文摘The inclusion of atrazine with 2-hydroxypropyl-β-cyclodextrin(HPCD) was synthesized by ultrasonic method, and it was characterized by UV, XRD and 1H NMR. The solubility in water and the bioactivity of the inclusion were also studied here. The results indicated that the UV maximum absorption wavelength of the inclusion remained at 223 nm, while its intensity decreased. The XRD peaks of atrazine disappeared, weakened and shifted in the inclusion, and the chemical shift of H-3 and H-5 of cyclodextrin inner cavity led to the upfield. The characterization data showed that the atrazine-HPCD inclusion had already formed. At the same time, the solubility of the atrazineHPCD inclusion in water became 20.08 times as that of atrazine. Moreover, the atrazine-HPCD inclusion had better herbicidal activity. When the concentration of the inclusion was 6.5 mg/mL, the inhibition ratios of the inclusion to taproot length, taproot fresh weight, sprout length and sprout fresh weight of barnyard grass were 66.96%, 57.22%, 70% and 57.53%, respectively, which were all higher than those of atrazine.
文摘Meat and meat products are extremely perishable, so special care and handling must be exercised during slaughtering operation. Moreover, due to its high nutritive value, deterioration set in immediately after slaughtered, therefore it is necessary to preserved meat, using simple techniques. One of such method of preservation is drying method to produced Intermediate Moisture Meat (IMM). The quality attributes and microbiological status of Kundi, a West African dried meat product (IMM) were studied over three months of storage period by comparing commercial products and laboratory Kundi products. Chemical and minerals composition and microbiological counts were reported. Moisture and water activity results indicated that the experimental Kundi was sufficiently dried to minimize microbial growth. Fat oxidation levels measured by free fatty acids (FFA, %) on extracted fats were unacceptably high for the commercial Kundi (2.64%), which may be a reflection of the oil used in spraying the products. Processing of Kundi, appears to have relative higher amounts of minerals than fresh meat but their relative solubility were lower. Aflatoxin levels far exceeded established safe limits for commercial samples while laboratory samples fell under the safe limits, resulting from the mould growth in each product, with laboratory samples having lower growth than commercial samples.
文摘The some physical and chemical properties values ofpepino fruit were determined. The mineral elements (AI, B, Ca, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, P, Se and Zn) of fruit were analysed by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). Organic acid contents were analysed via HPLC equipped Ca (3,256.96 mg/kg), K (43,465.60 mg/kg), P (7,907.32 mg/kg) Na (1,496.13 mg/kg) and Mg (2,541.12 mg/kg) were established as major minerals in fruits. These results show that pepino fruit may be useful for the evaluation of dietary information in important food crops.
文摘The white mulberry (Morus alba L.) had been forgotten in Europe or known only as a plant associated with breeding of mulberry silkworms (Bombyx mori L.). The initial studies have shown great potential of this plant in energy, food and pharmaceutical industries. The leaves and fruits contain very valuable bioactive substances, which may be used in health care. Antioxidants of plant origin include flavonoids and vitamin C (ascorbic acid), and these substances are present in high amounts in anatomical parts of white mulberry. It has also been reported on the medicinal properties of this plant and its use in preventing diseases, such as atherosclerosis, diabetes, obesity and cancer. The food industry increasingly uses the white mulberry in food to provide human organism with precious bioactive substances. Functional food, due to the presence in its composition of valuable components, is beneficial to human health. What is more, very fast growth of mulberry causes that biomass of the plant may be used as biofuel or energy plant. The aim of this paper is to present the possibility of using the white mulberry as a raw material for functional foods and as an energy plant.
基金supported by the Research Fund for the Doctoral Program of Higher Education of Chinathe Research and Development Program of Hubei Province,and the China Postdoctoral Science Foundation(2012M521461)
文摘Tetronate antibiotics, a growing family of natural products featuring a characteristic tetronic acid moiety, are of importance and of particular interest for their typical structures, especially the spirotetronate structure, and corresponding versatile biolog- ical activities. Considerable efforts have persistently performed since the first tetronate was isolated, to elucidate the biosyn- thesis of natural tetronate products, by isotope-labeled feeding experiments, genetical characterization of biosynthetic gene clusters, and biochemical reconstitution of key enzymatic catalyzed reactions. Accordingly, the biosynthesis of spirotetronates has been gradually determined, including biosynthesis of a polyketide-derived backbone for spirotetronate aglycone, incorpo- ration of a glycerol-derived three-carbon unit into tetronic acid moiety, formation of mature aglycone via Diels-AIder-like re- action, and decorations of aglycone with various deoxysugar moieties. In this paper, the biosynthetic investigations of natural tetronates are well documented and a common biosynthetic route for this group of natural products is summarized accordingly.
基金supported by the National Natural Science Foundation of China (21532007)
文摘The strained cyclopropane and/or cyclobutane subunits occurred in many complex natural products including terpenoids, steroids and alkaloids. Natural products with cyclopropane and/or cyclobutane motifs not only furnished fascinating structures, but also exhibited versatile biological activities, such as cytotoxic, anti-HIM antimicrobial, antiviral, and immunosuppressive effects. This review covered a large array of structurally unique natural products with strained cyclopropane and/or cyclobutane motifs and summarized their structural features, distributions, biological activities, as well as biogenetic considerations.
基金supported by the National Key Research Program of China(Nos.2016YFD0200107and 2016YFD0300802)the National Natural Science Foundation of China(No.41271311)+1 种基金the Earmarked Fund for China Agriculture Research System(No.CARS-03)the Science and Technology Service Network Initiative of Chinese Academy of Sciences(Nos.KFJ-SW-STS-142-03 and KFJ-EW-STS-083-2)
文摘Investigating the effects of residue chemical composition on soil labile organic carbon (LOC) will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil water content on soil LOC fractions and microbial properties were investigated in a laboratory incubation experiment. Maize shoot and root residues were incorporated into soil at 40% and 70% field capacity. The soils were incubated at 20 ℃ for 150 d and destructive sampling was conducted after 15, 75, and 150 d. Respiration, dissolved organic carbon (DOC), hot-water extractable organic carbon (HEOC), and microbial biomass carbon (MBC) were recorded, along with cellulase and β-glucosidase activities and community-level physiological profiles. The results showed that the cumulative respiration was lower in root-amended soils than in shoot-amended soils, indicating that root amendment may be beneficial to C retention in soil. No significant differences in the contents of DOG, HEOC and MBC, enzyme activities, and microbial functional diversity were observed between shoot- and root-amended soils. The high soil water content treatment significantly increased the cumulative respiration, DOC and HEOC contents, and enzyme activities compared to the low soil water content treatment. However, the soil water content treatments had little influence on the MBC content and microbial functional diversity. There were significantly positive correlations between LOC fractions and soil microbial properties. These results indicated that the chemical composition of maize residues had little influence on the DOC, HEOC, and MBC contents, enzyme activities, and microbial functional diversity, while soil water content could significantly influence DOC and HEOC contents and enzyme activities.
基金National Natural Science Foundation of China(Grant No.81374067)Shanghai Municipal Health Commission(Grant No.2018ZY002)
文摘Naturally occurring secolignans have drawn the considerable attention because of their novel structures and diverse biological activities.In recent years,various natural secolignans with extensive bioactivities have been reported in the literatures.In the present review,we summarized all the available information regarding the biosynthesis,distributions,separation methods,chemical structures,spectral characteristics,and biological activities of natural secolignans,and provided some valuable new insights for the further study.