Sensory and Nutritional Properties and Stability of Formulated Organic Food Flavour Enhancers

Most food flavours have been shown to contain high quantities of cooking salt, followed by flavour enhancers such as sodium glutamate, disodium inosinate, disodium guanylate and hydrogenated oils. Excess of these substances is associated with cardiovascular diseases and neurodegenerative disorders. In an effort to reduce the harmful effects of these synthetic substances, this study therefore aimed to formulate organic, nutritious food flavours with good storage stability from less harmful locally available food ingredients. A survey was carried out in 130 households and restaurants in the city of Yaoundé Cameroon, in order to evaluate the level of consumption of industrial flavours. Certain ingredients such as prawns, onions, garlic, white peppers, gingers and salt were used in some households as organic flavours. These ingredients and others were used to prepare 5 organic flavours. Their sensory and nutritional analyses and stability to storage within 90 days were evaluated. The survey revealed that 74.6% of respondents consume industrial flavours, with the cube flavour being the most widely consumed (81%). Two of the 5 organic flavours (434 and 634) had highest scores for general acceptability. The nutritional analyses of the formulae retained (434 and 634), showed that they contained: 11.08% and 10.68% fresh weight for moisture, 47.63% and 43.53% protein, 16.52% and 13.62% lipids, 2.20% and 2.44% fibres, 11.69% and 16.39% carbohydrates. Formula 434, the most accepted, had higher contents of Ca (257.97), Mg (115.91), K (1163), Zn (2.98), Cu (1.02) and Fe (12.43 mg/100g DM) while the second (634) had higher contents of sodium (3270.48) and manganese (2.18 mg/100g). Their water activity during storage in polypropylene bags for 90 days ranged from 0.39 - 0.58 at a temperature of 26.6˚C - 37˚C. The oxidative stability (90 days), determined by the acid and peroxide indices, was 9.18 - 14.13 mg KOH/g and 1.98 - 6.46 meq O2/Kg, respectively indicating good stability for 90 days of storage. The high levels of proteins and minerals in our two products justify their umami taste and can be used as highly nutritional food flavour enhancers to prevent cardiovascular diseases, especially in the elderly.

The Effect of Soil Enzymes and Polysaccharides Secreted by the Roots of Salvia miltiorrhiza Bunge under Drought,High Temperature,and Nitrogen and Phosphorus Deficits

Root exudates serve as crucial mediators for information exchange between plants and soil,and are an important evolutionary mechanism for plants’adaptation to environmental changes.In this study,15 different abiotic stress models were established using various stress factors,including drought(D),high temperature(T),nitrogen deficiency(N),phosphorus deficiency(P),and their combinations.We investigated their effects on the seedling growth of Salvia miltiorrhiza Bunge and the activities of Solid-Urease(S-UE),Solid-Nitrite Reductase(S-NiR),Solid-Nitrate Reductase(S-NR),Solid-Phosphotransferase(S-PT),and Solid-Catalase(S-CAT),as well as the contents of polysaccharides in the culture medium.The results showed that the growth of S.miltiorrhiza was inhibited under 15 stress conditions.Among them,13 stress conditions increased the root-shoot ratio.These 15 stress conditions significantly reduced the activity of S-NR,two combinations significantly improved the activity of S-NIR,they were synergistic stresses of high temperature and nitrogen deficiency(TN),and synergistic stresses of drought and nitrogen deficiency(DN)(p<0.05).The activity of S-UE was significantly improved under N,D,T,synergistic stresses of drought and high temperature(DT),DN,synergistic stresses of drought and phosphorus deficiency(DP),and synergistic stresses of high temperature,nitrogen,and phosphorus deficiency(TNP)stress conditions(p<0.05).Most stress combinations reduced the activity of S-PT,but D and T significantly improved it.(p<0.05).The N,DN,and TN stress conditions significantly reduced S-CAT activity.The P,DT,and synergistic stresses of drought,high temperature,and phosphorus deficiency(DTP)significantly decreased the total polysaccharide content of the soil(p<0.05).The research suggested that abiotic stress hindered the growth of S.miltiorrhiza and altered the behavior of root secretion.Roots regulated the secretion of several substances in response to various abiotic stresses,including soil nitrogen cycle enzymes,phosphorus transport-related enzymes,and antioxidant enzymes.In conclusion,plants regulate the utilization of rhizosphere substances in response to abiotic stresses by modulating the exudation of soil enzymes and polysaccharides by the root system.At the same time,soil carbon sequestration was affected by the adverse environment,which restricted the input of organic matter into the soil.

Screening for metabolic dysfunction-associated fatty liver disease:Time to discard the emperor’s clothes of normal liver enzymes?

Metabolic dysfunction-associated fatty liver disease(MAFLD)is the most prevalent chronic liver condition worldwide.Current liver enzyme-based screening methods have limitations that may missed diagnoses and treatment delays.Regarding Chen et al,the risk of developing MAFLD remains elevated even when alanine aminotransferase levels fall within the normal range.Therefore,there is an urgent need for advanced diagnostic techniques and updated algorithms to enhance the accuracy of MAFLD diagnosis and enable early intervention.This paper proposes two potential screening methods for identifying individuals who may be at risk of developing MAFLD:Lowering these thresholds and promoting the use of noninvasive liver fibrosis scores.

Timosaponin AⅢ induces drug-metabolizing enzymes by activating constitutive androstane receptor (CAR) via dephosphorylation of the EGFR signaling pathway

The current study aimed to assess the effect of timosaponin AⅢ(T-AⅢ)on drug-metabolizing enzymes during anticancer therapy.The in vivo experiments were conducted on nude and ICR mice.Following a 24-day administration of T-AⅢ,the nude mice exhibited an induction of CYP2B10,MDR1,and CYP3A11 expression in the liver tissues.In the ICR mice,the expression levels of CYP2B10 and MDR1 increased after a three-day T-AⅢ administration.The in vitro assessments with HepG2 cells revealed that T-AⅢ induced the expression of CYP2B6,MDR1,and CYP3A4,along with constitutive androstane receptor(CAR)activation.Treatment with CAR siRNA reversed the T-AⅢ-induced increases in CYP2B6 and CYP3A4 expression.Furthermore,other CAR target genes also showed a significant increase in the expression.The up-regulation of murine CAR was observed in the liver tissues of both nude and ICR mice.Subsequent findings demonstrated that T-AⅢ activated CAR by inhibiting ERK1/2 phosphorylation,with this effect being partially reversed by the ERK activator t-BHQ.Inhibition of the ERK1/2 signaling pathway was also observed in vivo.Additionally,T-AⅢ inhibited the phosphorylation of EGFR at Tyr1173 and Tyr845,and suppressed EGF-induced phosphorylation of EGFR,ERK,and CAR.In the nude mice,T-AⅢ also inhibited EGFR phosphorylation.These results collectively indicate that T-AⅢ is a novel CAR activator through inhibition of the EGFR pathway.

Engineering high amylose and resistant starch in maize by CRISPR/Cas9-mediated editing of starch branching enzymes

To improve the amylose content(AC)and resistant starch content(RSC)of maize kernel starch,we employed the CRISPR/Cas9 system to create mutants of starch branching enzyme I(SBEI)and starch branching enzyme IIb(SBEIIb).A frameshift mutation in SBEI(E1,a nucleotide insertion in exon 6)led to plants with higher RSC(1.07%),lower hundred-kernel weight(HKW,24.71±0.14 g),and lower plant height(PH,218.50±9.42 cm)compared to the wild type(WT).Like the WT,E1 kernel starch had irregular,polygonal shapes with sharp edges.A frameshift mutation in SBEIIb(E2,a four-nucleotide deletion in exon 8)led to higher AC(53.48%)and higher RSC(26.93%)than that for the WT.E2 kernel starch was significantly different from the WT regarding granule morphology,chain length distribution pattern,X-ray diffraction pattern,and thermal characteristics;the starch granules were more irregular in shape and comprised typical B-type crystals.Mutating SBEI and SBEIIb(E12)had a synergistic effect on RSC,HKW,PH,starch properties,and starch biosynthesis-associated gene expression.SBEIIa,SS1,SSIIa,SSIIIa,and SSIIIb were upregulated in E12 endosperm compared to WT endosperm.This study lays the foundation for rapidly improving the starch properties of elite maize lines.

Identification of key enzymes in lignocellulose biosynthesis from dynamic observations in maize stalks

Maize stalk lignin and cellulose contents are linked to lodging resistance,disease resistance,feed quality and ethanol conversion efficiency.After the six-leaf stage of maize(V6),these constituents are biosynthesized and accumulated under the control of related enzymes and genes.However,the key enzymes,critical MYB transcription factors,and their dynamic alterations pattern under natural field circumstances are still unknown.Hence,we selected five cultivars with significant differences in lignocellulose content and lodging resistance as testing materials,performed field experiments for two years,and investigated the dynamics of lignin and cellulose content,related enzyme concentrations,and gene expression levels in the 3^(rd) and 5^(th) internodes above the ground after V6.The results showed that lignin and cellulose content increased after V6,stabilizing during the silking stage.This study identified COMT(caffeic acid 3-Omethyltransferase),TAL(tyrosine ammonia-lyase)and PAL(phenylalanine ammonia-lyase)as the key enzymes of lignin biosynthesis,while ZmCOMT,ZmCesA10 and ZmCesA8 were identified as essential genes.ZmMYB8,ZmMYB31 and ZmMYB39 were involved in regulating the expression of genes related to lignin synthesis,with ZmMYB31 potentially acting as a key negative regulator,while ZmMYB39 and ZmMYB8 acting as positive regulators.The study also found that around 14 d after V6 was a critical stage for regulating lignocellulose synthesis in the 3^(rd) to 5^(th) basal internode.This provides a theoretical foundation for developing regulatory techniques and breeding new cultivars to enhance lodging and disease resistance as well as the utility of maize stalks.

Effect of Different Arbuscular Mycorrhizal Fungi Strains on Mineral Nutrition and Antioxidant Enzymes of Chrysanthemum morifolium

[Objective] The purpose was to study the effects of different arbuscular mycorrhizal fungi strains（AMF）on the mineral nutrition and antioxidant enzymes of Chrysanthemum morifolium.[Method] The pot experiment was conducted in the greenhouse,C.morifolium ＇Jinba＇ was inoculated with five kinds of AMF,N,P,K,malondial dehyde（MDA）content,as well as the superoxide dismutase（SOD）,peroxidase（POD） and catalase（CAT） activity in roots,leaves and petals of C.morifolium were measured at seedling and flowering stages.[Result] The G.i,G.e and G.m treatments could promote mineral nutrient absorption,increase N,P,K content in roots,leaves and petals of C.morifolium compared with the control without inoculation.The G.d、G.e and G.m treatments could significantly reduce MDA content in roots and petals,thus alleviating membrane permeability and lipid peroxidation.The G.i treatments could also improve the SOD,POD and CAT activities of C.morifolium,thereby increasing the capability of scavenging oxygen free radicals.[Conclusion] According to the comprehensive analysis,G.i was screened out as the best strain to improve mineral nutrition and antioxidant enzyme activities of C.morifolium.

Expression level of myocardial enzymes in patients with schizophrenia: Predictive value in the occurrence of violence

BACKGROUND Schizophrenic patients are prone to violence,frequent recurrence,and difficult to predict.Emotional and behavioral abnormalities during the onset of the disease,resulting in active myocardial enzyme spectrum.AIM To explored the expression level of myocardial enzymes in patients with schizo-phrenia and its predictive value in the occurrence of violence.METHODS A total of 288 patients with schizophrenia in our hospital from February 2023 to January 2024 were selected as the research object,and 100 healthy people were selected as the control group.Participants’information,clinical data,and labo-ratory examination data were collected.According to Modified Overt Aggression Scale score,patients were further divided into the violent(123 cases)and non-violent group(165 cases).RESULTS The comparative analysis revealed significant differences in serum myocardial enzyme levels between patients with schizophrenia and healthy individuals.In the schizophrenia group,the violent and non-violent groups also exhibited different levels of serum myocardial enzymes.The levels of myocardial enzymes in the non-violent group were lower than those in the violent group,and the patients in the latter also displayed aggressive behavior in the past.CONCLUSION Previous aggressive behavior and the level of myocardial enzymes are of great significance for the diagnosis and prognosis analysis of violent behavior in patients with schizophrenia.By detecting changes in these indicators,we can gain a more comprehensive understanding of a patient’s condition and treatment.

Research on Activities of Antioxidant Enzymes during Pigment Gland Morphogenesis in Cotton

[Objective] This study aimed to determine activities of antioxidant enzymes during gland morphogenesis in cotton, thoroughly explore physiological changes of cotton and provide a scientific basis for the cultivation of excellent cotton varieties. [Method] Based on determination of gossypol contents and antioxidant enzymes ac- tivities during gland morphogenesis in three cotton varieties （Chuanmian2802, Xiang- mian18 and XianwuN5）, metabolism of gossypol and morphogenesis of gland in cot- ton were explored. [Result] After gland morphogenesis, the content of gossypol in Chuanmian2802 was gradually reduced in the early period of seed germination, which slowly increased since the 5th d after germination; however, during the seed germination period, the content of gossypol in Xiangmian18 had a slowly increasing trend and was gradually close to the content of gossypol in Chuanmian2802. The results showed that activities of SOD, POD and CAT increased in seed germination, which was contributive to remove the superoxide radicals, decrease the peroxide lev- el, reduce damages to the membrane, enhance the body＇s resistance to lipid oxida- tion and increase resistance ability to stress. [Conclusion] This study laid the scientif- ic foundation for understanding the characteristics of gland morphogenesis in cotton and cotton cultivation by using gland traits.

Flavourzyme-Papain复合蛋白酶水解龙虾副产物工艺条件的研究

以底物浓度为10%、Flavourzyme与Papain复合酶比为1:1的条件,利用单因素试验和正交试验,研究了pH值、加酶量、温度、酶解时间对龙虾副产物蛋白质水解度的影响,在此基础上进一步确定了合适的底物浓度。结果表明,Flavourzyme-Papain复合蛋白酶水解龙虾副产物的最佳条件为:pH7.0、加酶量1.5%、温度50～55℃、时间5h,在底物浓度25%的条件下水解,最大水解度为26.2%。

Effects of Spores and Crude Toxins of Helminthosporium gramineum Rabenh f.sp.echinochloae on the Activity of Defensive Enzymes in Barnyardgrass

[Objective] This study aimed to explore the effects of spores and crude toxins of Helminthosporium gramineum Rabenh f. sp. echinochloae（HGE） on the ac- tivity of defensive enzymes of barnyardgrass [Echinochloa crus-galli （L.） Beauv.]. [Method] The effects of spores and crude toxins of HGE, as well as the mixture of spores and crude toxins on the activity of defensive enzymes in barnyardgrass were determined under laboratory conditions. [Result] Spores and crude toxins of HGE had varying degrees of effects on PAL and POD activity, and no obvious effect on SOD activity in barnyardgrass. In addition, spores and toxins had some similar im- pacts on the defensive enzymes in barnyardgrass. [Conclusion] Since toxins have similar effects on the hosts as spores of fungal pathogen do, they can be a substi- tute for the fungal pathogen in studying the partial pathogenic mechanism of this pathogen due to its complexity in pathogenic process.

Responses of soil enzymes to long-term CO_2 enrichment in forest ecosystems of Changbai Mountains

A study was conducted to determine the responses of soil enzymes （invertase, polyphenol oxidase, catalase, and dehydrogenase） to long-term CO2 enrichment at the Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences （42°24＇N, 128°28＇E; 738 m in elevation） in the northeast China during 1999-2006. Three treatments of the CO2 enrichment, designed as 500 μmol·mol-1 CO2 open-top chamber （OTC）, ambient control chamber and unchambered field （approx. 370 μmol·mol^-1CO2）, were conducted with Pinus koraiensis and Pinus sylvestriformis tree species. Soil sampling was made and analyzed separately in spring, summer and autumn in 2006 after the soil enzymes were exposed to elevated CO2 concentration （500 μmol·mol^-1） for eight growing seasons. Results showed that, at elevated CO2 concentration （500 μmol·mol^-1）, the activities of invertase （except for the summer samples of P. koraiensis） presented a remarkable decline in all growing seasons, while the activities of dehydrogenase had an increase but only part of the results was remarkable; the activities of polyphenol oxidase in P. sylvestriformis rhizosphere showed a remarkable decrease; the catalase activities increased in spring, while in turn were decline in other seasons. This study also revealed that the soil enzyme activities are significantly correlated with the tree species under the CO2 enhancement.

Effects of Ethametsulfuron on Protective Enzymes and Endogenous Hormones of Rice Seedling

[Objective] The aim was to explore physiological mechanism effects in growth promotion by ethametsulfuron of lower concentration through research on content variations of protective enzymes and endogenous hormones by ethametsulfuron of low concentration. [Method] Rice of different leaf ages were treated in ethametsulfuron of two concentrations through soil culture. Leaves of rice were col- lected after 15 d. POD activity, PPO activity, and contents of GA, ZR, and ABA were measured by guaiacol-hydrogen peroxide method, catechol method, and ELISA method, respectively. [Result] After treatment by ethametsulfuron at 2 μg/kg, activity of PPO was greatly enhanced, of POD was a little lower than that of control group; contents of GA and ZR increased a lot and of ABA decreased much; GA/ABA val- ues were higher than that of control group. In contrast, with treatment of ethamet- sulfuron at 20 μg/kg, activity of POD was greatly increased, of PPO was a little low- er than that of control group; contents of GA, ZR increased a lot and of ABA was greatly decreased; ratio of GA and ABA was smaller than that of control group. Among treated leaves during the period when the seventh leaf grew, three hormones contents were so close to that of control group. [Conclusion] If rice was tested with ethametsulfuron of 2 μg/kg, value of GA/ABA in leaves was higher than that of con- trol group, for which rice growth would be promoted. When the concentration was 20 μg/kg, ratio of GA and ABA was smaller than that of control group, for which, rice growth would be inhibited, and during the seventh leaf growing, ethametsul- furon＇s effect on rice growth was weaker than that of term before the fourth one growing.

Effects of Heavy-ion Beams Irradiation on Survival Rate and Antioxidant Enzymes of Sweet Sorghum Seedlings

[Objective] This study aimed to investigate the effects of heavy-ion beams irradiation on the seed germination potential, survival rate, antioxidant enzyme activi- ties and lipid peroxidation of sweet sorghum. [Method] The dry seeds were irradiated by ＇2（36. heavy ion beams with absorbed doses： 0, 40, 80, 120, 160 and 200 Gy, respectively. Then, the seed germination potential, survival rate, antioxidant enzyme activities and lipid peroxidation of sweet sorghum were measured. [Result] Heavy-ion beams irradiation exhibited different influence on germination potential and survival rates. Germination rate showed a downward trend, but the corresponding survival curve of seedlings was saddle-shaped. The activities of SOD, POD, CAT and ASA- POD changed in different trends as well. The MDA content rose toward increasing irradiation dose, suggesting that high dose of heavy-ion beams irradiation enhanced the damage to membrane of sweet sorghum seedlings. [Conclusion] After being irra- diated, germination potential and survival rates of sweet sorghum were decreased, and antioxidant enzymes activity changed greatly. This study laid the basis for fur- ther work on breeding and improvement of sweet sorghum irradiated by ,^（12）C^（6＋） heavy ion beams.

Effect of Botryosphaeria berengeriana f.sp.piricola and Biocontrol Bacteria on the System of Antioxidant Enzymes in Pears

[Objective] The aim was to understand defense mechanism of pear after inoculated Botryosphaeria berengeriana f. sp. piricolan and mechanism of antioxidant enzymes of biocontrol bacteria. [Method] Pears were treated by Botryosphaeria berengeriana f. sp. piricolan and bio control bacteria, and the change of antioxidant enzymes were determined. [Result] The biocontrol bacteria had little effect on MDA;the content of MDA treated by B. berengeriana reached high peak in 48 h, was 10.22nmol/g which was 1.86 times of CK; the content of MDA treated by B. berengeriana and biocontrol bacteria reached high peak in 24 h, was 8.92 nmol/g which was1.62 times of CK. The content of SOD treated by biocontrol bacteria reached high peak in 48 h, was 126.69 U/[g（FW）·min] which was 1.54 times of CK; the contents of SOD treated by B. berengeriana as well as B. berengeriana and biocontrol bacteria reached high peak in 24 h, were 122.10 and 135.32 U/[g（FW）·min] which were 1.48 and 1.65 times of CK respectively; the contents of POD on biocontrol bacteria treatment, B. ana treatment as well as B. berengeriana and biocontrol bacteria treatment reached high peak in 24 h, were 385.34, 342.50 and 290.00 U/[g（FW）·min] which were 1.83, 1.62 and 1.38 times of CK respectively. The contents of CAT on biocontrol bacteria treatment, B. rengeriana treatment as well as B. berengeriana and biocontrol bacteria treatment reached high peak in 6 h, were 133.33,114.17 and 113.35 U/[g（FW）·min] which were 1.33, 1.14 and 1.13 times of CK respectively. The biocontrol bacteria had little difference in CK; the content of PPO of B. berengeriana treatment reached high peak in 12 h, was 81.86 U/[g（FW）·min]which was 1.76 times of CK; B. berengeriana and biocontrol bacteria treatment reached high peak in 24 h, was 70.00 U/[g（FW）·min] which was 1.50 times of CK.[Conclusion] B. berengeriana and biocontrol bacteria had more effect on MDA; both B. berengeriana and biocontrol bacteria could increase the excitation of SOD enzyme activity; both B. berengeriana and biocontrol bacteria could increase the excitation of POD enzyme activity; both B. berengeriana and biocontrol bacteria could increase the excitation of CAT enzyme activity; using biocontrol bacteria alone had not obvious effect on PPO, B. berengeriana could increase the excitation of PPO enzyme activity.

Effects of Exogenous Salicylic Acid Derivative on the Resistance to TMV and Activity of Defense Enzymes of Tobacco

[Objective] This study aimed to evaluate the effects of exogenous salicylic acid derivatives on tobacco resistance to TMV and activity of defense enzymes. [Method] The tobboco leaves were treated by exogenous salicylic acid derivatives. Then, the disease occurrence was observed, and the activity of phenylalanin ammo- nia lyase （PAL） and peroxidase （POX） were measured. [Result] Exogenous salicylic acid derivative increased the activities of PAL and POX, while did not influence the resistance to TMV. [Conclusion] The result provides a theoretical basis for the study of plant disease resistance mechanisms.

Recent advances in immobilized enzymes on nanocarriers

Recent progress in nanotechnology has provided high-performance nanomaterials for enzyme immobilization.Nanobiocatalysts combining enzymes and nanocarriers are drawing increasing attention because of their high catalytic performance,enhanced stabilities,improved enzyme-substrate affinities,and reusabilities.Many studies have been performed to investigate the efficient use of cellulose nanocrystals,polydopamine-based nanomaterials,and synthetic polymer nanogels for enzyme immobilization.Various nanobiocatalysts are highlighted in this review,with the emphasis on the design,preparation,properties,and potential applications of nanoscale enzyme carriers and nanobiocatalysts.

Effect of ^(12)C^(6+) Ions Beam Irradiation on Seed Germination and Enzymes Activity in Seedlings of Sweet Sorghum

[ Objective] The aim was to study the effect of 12C6 ＋ ions beam irradiation to two varieties of sweet sorghum on seed germination and some enzymes activity in seedlings with different doses, and provided a theoretical foundation for sweet sorghum breeding. [ Method] After germination, the germination potential, germination fraction and enzyme activity were detected, respectively. [ Result] The results showed that with the dose increased, the germination potential of sweet sorghum increased first and then decreased, while their germination fraction presented ＂shoulder like shape＂ ; the activity of LDH, SOD, CAT and GSH-Px increased first and then decreased with doses, they presented slight differences among different enzymes. [ Conclusion] Low dose radiation could accelerate germination of sweet sorghum seeds and enzyme activity could remain at a relatively high level. Enzyme activity decreased with high doses and the growth of sweet sorghum was inhibited.

Changes of Proline Content,Activity,and Active Isoforms of Antioxidative Enzymes in Two Alfalfa Cultivars Under Salt Stress

The plants of two elfalfa （Medicago sativa L.） cultivars differing in salt tolerance were subjected to three salt treatments, 70, 140, and 210 mM NaCl for 7 days. Root, shoot, and leaf growths were inhibited by increased salt treatments in both cultivars, and at 140 and 210 mM salt treatments, Zhongmu 1 had significantly higher root, shoot, and leaf dry weights per plant than Deft. The malondialdehyde （MDA） accumulation in Deft was considerably greater than in Zhongmu 1, indicating a higher degree of lipid peroxidation at 140 and 210 mM salt treatments. The changes in the activity and active isoforms of antioxidant enzymes such as superoxide dismutase （SOD, EC 1.15.1.1）, catalase （CAT, EC 1.11.1.6）, peroxidase （POD, EC 1.11.1.7）, and ascorbate peroxidase （APOX, EC 1.11,1.11）, accumulation of free proline, and rate of lipid peroxidation in leaves of two alfalfa cultivars were also investigated. After stress, the activity and active isoforms of antioxidative enzymes were altered and the extent of alteration varied between the cultivar Deft and Zhongmu 1. The proline accumulation in Deft was considerably greater than in Zhongmu 1 at 210 mM salt treatment. This indicated that proline accumulation may be the result, instead of the cause, of salt tolerance.

Effects of melatonin on lipid peroxidation and antioxidant enzymes in streptozotocin-induced diabetic rat testis

Aim： To examine the effects of melatonin treatment on lipid peroxidation （LPO） and the activities of antioxidant enzymes in the testicular tissue of streptozotocin （STZ）-induced diabetic rats. Methods： Twenty-six male rats were randomly divided into three groups as follows： group Ⅰ, control, non-diabetic rats （n = 9）; group Ⅱ, STZ-induced, untreated diabetic rats （n = 8）; group Ⅲ, STZ-induced, melatonin-treated （dose of 10 mg/kg·day） diabetic rats （n = 9）. Following 8-week melatonin treatment, all rats were anaesthetized and then were killed to remove testes from the scrotum. Results： As compared to group Ⅰ, in rat testicular tissues of grouap Ⅱ, increased levels of malondialdehyde （MDA） （P 〈 0.01） and superoxide dismutase （SOD） （P 〈 0.01） as well as, decreased levels of catalase （CAT） （P 〈 0.01） and glutathione peroxidase （GSH-Px） （P 〉 0.05） were found. In contrast, as compared to group Ⅱ, in rat testicular tissues of group Ⅲ, levels of MDA decreased （but this decrease was not significant, P 〉 0.05） and SOD （P 〈 0.01） as well as CAT （P 〈 0.05） increased. GSH-Px was not influenced by any of the treatment. Melatonin did not significantly affect the elevated glucose concentration of diabetic group. At the end of the study, there was no significant difference between the melatonin-treated group and the untreated group by means of body and testicular weight. Conclusion： Diabetes mellitus increases oxidative stress and melatonin inhibits lipid peroxidation and might regulate the activities of antioxidant enzymes of diabetic rat testes.