Effect of Quercus infectoria and Rosa damascena on lipid profile and atherosclerotic plaque formation in rabbit model of hyperlipidemia

Hyperlipidemia is the cause of many complications in the human societies. In this study, the effect of methanol extracts of Quercus infectoria (QI) galls and Rosa damascena (RD) Mill flower were studied on lipid profile and atherosclerotic plaques formation in hyperlipidemic rabbits. Thirty-six New Zeland white rabbits randomly divided into 6 groups as control (I), hyperlipidemic (II), hyperlipidemic+QI (III), hyperlipidemic+RD (IV), +Atorvastolin (V) and hyperlipidemic+Orlistat (VI) and were fed with high fat diet (0.5% cholesterol and 16% hydrogenated vegetable oil) for 45 days. At the end of the study period, lipid profile and plaque formation were assessed. Total Cholesterol (TC), Low Density Lipoprotein (LDL) and Triglyceride (TG) levels were significantly increased in hyperlipidemic group compared with control group (p < 0.001). Methanol extract consumption of Quercus infectoria significantly decreased plasma levels of TC, TG and LDL (p < 0.001). It also decreased plaques formation in semi lunar valve and thoracic aorta. Rosa damascena mill flower methanol extract moderately decreased the levels of TC, TG, LDL and plaques formation but it was not significant. HDL levels and weight of animals did not show significant difference among groups. Based on the doses used in this study, our finding indicated that QI but no RD methanol extract has anti atherogenic and hypolipidemic activities.     

The effects of harvest date,fermentation duration and Tween 20 treatment on essential oil content and composition of industrial oil rose (Rosa damascena Mill.)

The essential oil of Rosa damascena Mill. is one of the most valuable and important base material in the flavor and fragrance industry. The aim of this study was to determine the effects of harvest date, fermentation duration and Tween 20 treatment on the essential oil content and composition of the rose petals. The essential oil content and composition were significantly different in the petals harvested at various dates (May 24, June 1, 8, and 15, 2002). The highest oil content was found on May 24 harvest (0.040%), and then a gradual decrease was observed up to last harvest date (0.032%). The highest percentages of geraniol, nerol, and phenylethyl alcohol were obtained from the petals harvested on May 24. However, the highest percentages of citronellol and linalool were found from the petals harvested on June 8. The petals collected freshly were fermented for various duration (0, 12, 24, and 36 h) at 25 °C in sacks. The highest essential oil content was found in the non-fermented petals. As fermentation duration increased, essential oil content gradually decreased. The most significant changes during the fermentation were observed in citronellol and geraniol contents. Citronellol/geraniol (C/G) ratio increased from 0.57 to 10.31 throughout the fermentation. In the other experiment, Tween 20 was added into the distillation water at various concentrations (0, 1000, 2500, and 5000 ppm). Although Tween 20 generally raised the contents of essential oil, it did not significantly influence the oil composition. The highest oil content (0.045%) was obtained from the distillation treated with 2500 ppm of Tween 20. Oil content had high positive correlations with geraniol and linalool contents (r=0.55 and 0.53, respectively), but high negative correlation with citronellol content (r=−0.48).     

山刺玫果发酵保健凉茶的研制

目的优化刺玫果发酵保健凉茶的工艺。方法以单因素实验为基础,刺玫果发酵保健凉茶的总黄酮提取率为指标,采用Plackett-Burman设计筛选刺玫果发酵保健凉茶的主要影响因素;再以凉茶的总黄酮提取率和活菌数为评价标准,采用Box-Behnken设计对影响刺玫果发酵保健凉茶的主要因素进一步优化,对实验数据进行多元线性回归、二项式拟合,分析预测最佳工艺。结果刺玫果发酵保健凉茶的最佳工艺条件为:浸提时间为60 min,料液比为1:25,乳酸菌接种量为3%,发酵温度为37℃,发酵时间为14h,糖添加量为5%。结论采用Plackett-Burman设计和Box-Behnken设计法优化刺玫果发酵保健凉茶的工艺科学合理,优选的工艺稳定可靠,为其他类型中药饮料的研制和开发提供了可靠依据。     

Effect of N. sativa oil on impaired glucose tolerance and insulin insensitivity induced by high-fat-diet and turpentine-induced trauma

The aim of this study was to investigate the effect of N. sativa oil on impaired glucose tolerance and insulin insensitivity induced by high-fat diet and trauma. Three dietary groups were used in this study; Rat-Chow (RC), N. sativa oil diet (Combination 4% N. sativa oil and 16% butter oil) (NSOD) and 20% Butter Oil Diet (BOD). Each group was subdivided in two groups; control and trauma. Diets were supplemented for five consecutive weeks body weight increase per week was calculated. At end of the dietary treatments, single dose (2 mL kg(-1) body weight) of turpentine was injected in the dorso-lumber region. Intravenous glucose tolerance test (i.v. GTT) was performed, insulinogenic index and insulin sensitivity was measured. The results showed butter oil diet significantly increased the body weights and visceral fats compared other two groups, respectively. Fasting glucose levels did not change in trauma induced rats while insulin levels increased significantly and it found highest in butter oil diet fed animals. Impaired glucose tolerance was found sever in BOD fed traumatized rats. N. sativa oil diet protected impaired glucose tolerance and insulin insensitivity induced either via saturated fatty acids or injury. In conclusion, N. sativa oil may be used in post surgery diabetic patients to prevent the long going adverse effects from surgical trauma.     

Low dose vaginal misoprostol versus prostaglandin E2 suppository for early uterine evacuation: a randomized clinical trial

Misoprostol is a cheap product of prostaglandin E1 which has gained interest in pregnancy termination. The aim of this study was to compare the effect of vaginal misoprostol and prostaglandin E2 suppository in pregnancy termination before 20 weeks of gestational age. In this clinical trial, 111 participants under 20 weeks of gestational age who needed pregnancy termination were enrolled. They were divided into two groups misoprostol and prostaglandine E2 treatment. Fifty four people received vaginal misoprostol as 25 microg per 4 h up to 3 days and 57 participants received prostaglandine E2 vaginal suppositories. Data were analyzed using SPSS software. Mean age of participants was 27.5 years and its standard deviation was 6.1 years. Mean gestational age was 13.1 weeks based on sonographic measurement and it was 14.5 weeks by LMP estimation. Mean induction to evacuation time was 3.1 days and in misoprostol group was 2.4 +/- 0.88 days. Half of the patients in control group and 70% of them in misoprostol group succeeded pregnancy termination in 48 h. Vaginal misoprostol compared to prostaglandine E2 vaginal suppository has higher efficacy in shorter time.     

Antidiabetic effect of essential oil from Artemisia sieberi growing in Jordan in normal and alloxan induced diabetic rats

The aim of this study was to evaluate the effects of essential oil extracted from aerial parts of Artemisia sieberi in normal and alloxan induced diabetic rats. Fifty rats were divided into five groups of 10 each. Group I normal rats received 1 mL day(-1) of dimethyl sulfoxide (control); group II normal rats received a single dose (80 mg kg(-1) b.wt.) of essential oil extract of Artemisia sieberi; group III diabetic rats received 1 mL day-of dimethyl sulfoxide; group IV diabetic rats received the oil extract (80 mg kg(-1) b.wt.); group V diabetic rats received metformin (14.2 mg kg(-1) b.wt.). All treatments were orally administered once a day for six weeks. Changes in blood glucose concentration, body weight and food and water intake were measured and the data obtained were compared with that of metformin. The essential oil extract significantly (p < 0.05) lowered blood glucose level as well as food and water intake in diabetic rats accompanied by an increase in body weight gain with no apparent side effect when compared with untreated diabetic rats. These effects were found to be closely similar to that of metformin, a common antidiabetic drug. On other hand, no apparent improvement on body weight gain in diabetic rats treated with metformin. In addition, for all parameters measured, the oil extract showed no effect in normal rats. In conclusion, the essential oil of Artemisia sieberi exhibited antidiabetic activity in alloxan-induced diabetic rats. Present findings support the possible use of the essential oil of Artemisia sieberi as a remedy for diabetes mellitus in humans.     

Arthroscopically-assisted vs. open surgery in repairing anterior cruciate ligament avulsion

The management of an Anterior Cruciate Ligament (ACL) avulsion is principally by surgery. There are two major techniques in this regard; fixation through open surgery (arthrotomy) or arthroscopically-assisted repair. These are not new in the literature; however, the debate regarding the better approach is still under debate. This study focused on comparing outcome and consequences of arthroscopically-assisted vs. open surgery in repairing ACL avulsion. In a randomized clinical trial, 44 patients with unilateral ACL avulsion were recruited in Tabriz Shohada teaching Centre during a 12 month period of time. These patients were randomized in two equal age and sex-matched groups underwent either arthroscopically-assisted or open ACL repair. The constructive technique was the same in both groups without using any graft. The minimum follow-up period was 6 months including 3 weeks, 3 months and 6 months postoperatively. Range of Motion (ROM), laxity, Anterior Drawer Test (ADT) result, duration of hospital stay, wound status, nonunion and return to previous work were compared between the two groups. Mean time of suture removal (p = 0.10), minimum and maximum ROM at months 3 (p = 0.43 and 0.22, respectively) and 6 (p = 0.73 and 0.77, respectively), ADT at months 3 and 6 (p = 0.16 for both), laxity at month 6 (p = 0.28) and wound status at week 3 (p = 0.35) were not significantly different between the two groups. There was no case of nonunion at month 6 in either group. The mean hospital stay was significantly shorter in the arthroscopy group (3.77 +/- 0.92 vs. 2.50 +/- 0.51 days; p < 0.001). The mean laxity score was significantly higher in the open surgery group at month 3 (4.82 +/- 0.59 vs. 4.45 +/- 0.60; p = 0.05). The rate of nonunion was significantly higher in the open surgery group at month 3 (40.9% vs. 9.1%; p = 0.02). Patients in the arthroscopically-assisted technique group returned sooner to previous work (17.41 +/- 1.53 vs. 14.82 +/- 0.96 weeks; p < 0.001). Based on our results, arthroscopically-assisted reconstruction of ACL avulsion is superior to open surgery.     

肉桂精油复合壳聚糖涂膜对采后番木瓜炭疽病的防治效果及作用机制分析

番木瓜是我国著名的热带、亚热带水果之一,但番木瓜属于呼吸跃变型果实,采后不耐贮运,其中由炭疽病引起的腐烂损失最为严重。因此,如何防治番木瓜采后炭疽病,降低番木瓜腐烂损失,延长贮藏保鲜期,成了制约番木瓜产业健康发展的瓶颈问题。本文以‘大青’番木瓜为试验材料,以绿色环保的肉桂精油-壳聚糖复合保鲜液为处理手段,研究其对采后番木瓜炭疽病的防治效果及作用机制,为我国番木瓜采后贮运保鲜产业发展提供理论依据和应用参考。分别用0.5%壳聚糖、0.5%壳聚糖+0.3%肉桂精油、0.5%壳聚糖+0.5%肉桂精油、0.5%壳聚糖+0.7%肉桂精油溶液对采后番木瓜果实进行喷雾处理,清水处理作为对照,处理后的番木瓜分为2组,其中一组处理后置于25℃下恒温贮藏,定期测定果实病情指数;另一组处理后置于25℃下恒温贮藏24 h后,在果面刺伤接种番木瓜炭疽菌,定期调查果实病斑直径,并对果皮进行取样,测定不同处理果实的抗病相关物质含量和抗病相关酶活性的变化情况。番木瓜炭疽菌的离体抑菌实验采用含药PDA平板抑菌法进行测定。研究结果表明:0.5%壳聚糖+0.3%肉桂精油处理对番木瓜炭疽病的防治效果最好,复合处理可完全抑制离体番木瓜炭疽菌的生长和产孢,复合处理显著降低了番木瓜果实的病斑直径,提高了抗病相关物质木质素、总酚(TP)和过氧化氢(H₂O₂)的含量,提高了抗病相关酶苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和β-1,3葡聚糖酶(β-1,3-GA)的活性,但对几丁质酶(CHI)活性影响不大。由此可见,肉桂精油复合壳聚糖涂膜对番木瓜炭疽菌有较好的防控效果,一方面是由于复合处理抑制了番木瓜炭疽菌的生长,另一方面是复合处理诱导番木瓜果实提高了抗病性。因此,适宜浓度的肉桂精油复合壳聚糖涂膜处理为防控番木瓜采后炭疽病提供了一种绿色新途径。     

肉桂精油复合壳聚糖涂膜对采后番木瓜炭疽病的防治效果及作用机制分析

番木瓜是我国著名的热带、亚热带水果之一,但番木瓜属于呼吸跃变型果实,采后不耐贮运,其中由炭疽病引起的腐烂损失最为严重。因此,如何防治番木瓜采后炭疽病,降低番木瓜腐烂损失,延长贮藏保鲜期,成了制约番木瓜产业健康发展的瓶颈问题。本文以‘大青’番木瓜为试验材料,以绿色环保的肉桂精油-壳聚糖复合保鲜液为处理手段,研究其对采后番木瓜炭疽病的防治效果及作用机制,为我国番木瓜采后贮运保鲜产业发展提供理论依据和应用参考。分别用0.5%壳聚糖、0.5%壳聚糖+0.3%肉桂精油、0.5%壳聚糖+0.5%肉桂精油、0.5%壳聚糖+0.7%肉桂精油溶液对采后番木瓜果实进行喷雾处理,清水处理作为对照,处理后的番木瓜分为2组,其中一组处理后置于25℃下恒温贮藏,定期测定果实病情指数;另一组处理后置于25℃下恒温贮藏24 h后,在果面刺伤接种番木瓜炭疽菌,定期调查果实病斑直径,并对果皮进行取样,测定不同处理果实的抗病相关物质含量和抗病相关酶活性的变化情况。番木瓜炭疽菌的离体抑菌实验采用含药PDA平板抑菌法进行测定。研究结果表明:0.5%壳聚糖+0.3%肉桂精油处理对番木瓜炭疽病的防治效果最好,复合处理可完全抑制离体番木瓜炭疽菌的生长和产孢,复合处理显著降低了番木瓜果实的病斑直径,提高了抗病相关物质木质素、总酚(TP)和过氧化氢(H₂O₂)的含量,提高了抗病相关酶苯丙氨酸解氨酶(PAL)、过氧化物酶(POD)和β-1,3葡聚糖酶(β-1,3-GA)的活性,但对几丁质酶(CHI)活性影响不大。由此可见,肉桂精油复合壳聚糖涂膜对番木瓜炭疽菌有较好的防控效果,一方面是由于复合处理抑制了番木瓜炭疽菌的生长,另一方面是复合处理诱导番木瓜果实提高了抗病性。因此,适宜浓度的肉桂精油复合壳聚糖涂膜处理为防控番木瓜采后炭疽病提供了一种绿色新途径。     

Common carotid artery intima-media thickness and atherosclerotic plaques in carotid bulb in patients with chronic kidney disease on hemodialysis: a case-control study

The Common Carotid artery Intima-Media Thickness (CCIMT) can reflect systemic atherosclerosis in renal patients on hemodialysis. This study aimed to compare CCIMT measured by color Doppler ultrasonography between two groups including dialytic patients and normal subjects. In this case-control setting, 48 patients with Chronic Kidney Disease (CKD) on hemodialysis (case group) and 46 age and sex-matched healthy subjects (control group) were enrolled in this study. Color Doppler ultrasound was used to measure CCIMT and determine presence of atherosclerotic plaques in carotid bulb in both groups. Various laboratory parameters were also determined. Serum levels of triglyceride, total cholesterol, low-density lipoprotein, fasting sugar, ionized calcium, inorganic phosphorus and magnesium were comparable between the two groups. Hypertension and elevated levels of serum C-reactive protein, as well as the mean levels of serum non-fasting homocysteine and phosphate were significantly higher in the case group. Mean levels of serum high-density lipoprotein and albumin were significantly higher in the controls. Mean maximum CCIMT was significantly higher in the case group than in controls (0.73 +/- 0.15 vs. 0.68 +/- 0.08 mm, p = 0.01) even after adjusting for other confounding variables. Frequency of patients with atherosclerotic plaques in carotid bulbs was not significantly different between case and controls. In conclusion, this study showed that CCIMT is significantly higher in CKD patients on hemodialysis comparing with matched normal counterparts. Furthermore, this difference was independent of other conventional risk factors for atherosclerosis.     

Metformin as an adjunct to insulin for glycemic control in patients with type 2 diabetes after CABG surgery: a randomized double blind clinical trial

Perioperative hyperglycemia is common in patients with type 2 diabetes undergoing Coronary Artery Bypass Graft (CABG) surgery and there is a direct relation between postoperative hyperglycemia and mortality rate in these patients. The aim of the present study is to determine the efficacy of metformin on glycemic control in diabetic patients after CABG surgery. In a randomized double blind clinical trial, 100 patients with type 2 diabetes admitted in open heart ICU after CABG surgery in Mazandaran Heart Center were enrolled. They were randomly assigned to two intervention and control groups. Three hours after extubation, therapeutic antiglycemic regimens were applied in these two groups and continued for three days. Intervention group received regular insulin infusion along with two metformin 500 mg tablets per twelve hours while control group received regular insulin infusion with two placebo tablets per twelve hours. Blood glucose level and other parameters were measured and recorded in determined intervals. To analyze the data, independent T-test, paired T-test, Mann-Whitney and repeated measure ANOVA tests were employed. Mean blood glucose level was not significantly different in the two groups at the beginning of the ICU admission; however, mean glucose level in insulin-metformin group, twelve hours after the initiation of the study, was significantly lower than insulin group (p < 0.05). In addition, mean doses of potassium and insulin demand as well as mean number of episodes of hyperglycemia, hypoglycemia and glucose levels out of the accepted range were significantly lower in insulin-metformin group (p < 0.05). Alterations in mean levels of lactate, BE, pH and creatinine were not statistically significant in these two groups. It seems that adding metformin to insulin leads to a better glycemic control in type two diabetic patients undergoing CABG surgery without causing metabolic acidosis. Therefore, it might be a potential option in blood glucose control protocol in this group of patients.     

Effect of oral administration of fenitrothion on biochemical and hematological parameters in rats

The aim of this study was to evaluate the effects of acute exposure to various doses of fenitrothion (FNT) on level of serum glucose, total protein, triglycerides (TG), total cholesterol (TC) and some hematological parameters. The study was conducted on 8-week-old male Wistar rats that divided into four groups (three experimental groups and one control group), were treated orally with different doses (25, 50 and 100 mg kg(-1)) of fenitrothion for 28 consecutive day. After treatment, blood samples were collected for biochemical and hematological studies. Present results demonstrated that exposed groups led to significant dose-dependent increase in serum glucose and cholesterol levels. Significant decrease was observed in some hematological parameters [Red Blood Cell (RBC) counts, Hemoglobin (Hb), Haematocrite (Ht) and Mean Corpuscular Hemoglobin (MCH) values]. Serum total protein and triglycerides were also decreased not significantly in exposed groups when compared with control. Generally, the degrees of observed variations were found to be dose dependent.     

广陈皮原料茶枝柑与其他典型柑橘成分差异分析

本文以广陈皮原料茶枝柑为对照,探究了其他典型的柑橘原料在可溶性糖、可溶性蛋白质、总黄酮、总多酚等方面的差异,分析其他橘皮作为茶枝柑替代品的可行性。结果表明,温州蜜柑、脐橙、湖北柑果皮的可溶性糖、可溶性蛋白质、总黄酮、总多酚含量与茶枝柑果皮相比均差异显著;采用GC-MS法检测出茶枝柑果皮精油的成分主要是D-柠檬烯、萜品烯、γ-松油醇、2-甲氨基-苯甲酸甲酯等,3种典型柑橘皮原料中的精油特征成分及D-柠檬烯含量与茶枝柑最为接近的均为脐橙。综合以上分析可知,脐橙作为广陈皮原料的替代品是最具前景的。     

Improvement of essential oil yield of oil-bearing (Rosa damascena Mill.) due to surfactant and maceration

The essential oil content of the oil-bearing rose (Rosa damascene Mill.) is relatively low, around 0.3-0.4 mL kg⁻¹ in fresh flowers. There is a need to increase essential oil yield of oil-bearing rose. The objective was to examine the effect of Tween 20 (polyoxyethylene sorbitan monolaurate) applied with, or without, maceration of flowers on oil content and composition of oil-bearing rose harvested at beginning of flowering, full bloom, and end of flowering. Addition of Tween 20 at 1000 mL L⁻¹ and 2500 mL L⁻¹ increased essential oil yield by 26% (to 0.44 mL kg⁻¹) and 54% (to 0.54 mL kg⁻¹) respectively relative to the untreated control that gave 0.35 mL kg⁻¹ yield. Maceration, in combination with the addition of Tween 20 at 1000 mL L⁻¹ and Tween 20 at 2500 mL L⁻¹, increased oil yield by 69% (to 0.59 mL kg⁻¹) and 94% (to 0.68 mL kg⁻¹) respectively. Among the three phenological phases of harvest, harvesting at the beginning of flowering gave the highest yield followed by the full bloom and then by the end of flowering phases. Since the interaction effect was not significant, the differences obtained among the treatments were regardless of the phase, and vice versa. Treatments did not significantly alter composition of the essential oil. Postharvest pre-extraction application of Tween 20 in combination with maceration could be used in the rose industry for increasing the essential oil yield.     

Effect of planting date on growth, development, aerial biomass partitioning and essential oil productivity of wild marigold (Tagetes minuta) in mid hills of Indian western Himalaya

A field investigation was conducted at the Institute of Himalayan Bioresource Technology, Palampur during the year 2005 to study the effect of planting dates on duration of growth and development in wild marigold (Tagetes minuta). Duration of growth phases (vegetative phase to budding phase and budding phase to 50% flowering phase), aerial biomass partitioning and essential oil production were analysed. Plantings were done in seven consequent meteorological standard weeks (MSWs) starting from the 30th MSW (30 July–5 August). Planting time coincided with distinct changes in weather parameters and consequently significant variation in the performance of the crop. The results indicated that the crop planted in the 30th and 31st MSW had the longest duration of growth and highest aerial biomass. But it partitioned more biomass towards the stem, whereas the crop planted in the 35th MSW produced significantly less biomass than the former and partitioned more towards leaf and flower and had maximum essential oil content and production. The crop planted at the 36th MSW had the minimum field duration of growth of 50 days, but the partitioning towards leaf and flower were higher than the longest field duration of growth (30th MSW). The study clearly indicated that planting dates had profound influence on growth and development of T. minuta as reflected from the significant variation on growth phase duration, aerial biomass partitioning, herb and essential oil yield.     

The effects of volatile oils on in vitro potato sprout growth

Summary The effects of 10 volatile oils and their main compounds on potato sprout growth were investigated in vitro. Sprout growth was inhibited especially by the volatile oils fromOriganum onites, Rosa damascena, Carum carvi, Mentha piperita, Echinophora tuneifolia andCoriandrum sativum. The major compound of volatile oils was carvacrol (78.2%) inO. onites, citronellol (46.7%) inR. damascena, S-(+)-carvone (54.9%) inC. carvi, menthol (44.1%) inM. piperita, α phelladrene (45.9%) inE. tuneifolia and linalool (76.5%) inC. sativum. The results showed that some volatile oils rich in monoterpenic compounds such as carvacrol, citronellol, geraniol, nerol and S-(+)-carvone were able to prevent the growth of sprouts and extend the storage-life of the potato tubers.     

Effect of growth stage on the content and composition of the essential oil and phenolic fraction of sweet marjoram (Origanum majorana L.)

The variation in the content and composition of Origanum majorana L. essential oil has been studied. Plant material has been harvested at four phenological stages (early vegetative, late vegetative, budding and full-flowering). Essential oil yield varied from 0.04 to 0.09% reached during the full-flowering stage. Analysis of the essential oils by GC and GC/MS revealed the presence of 38 components represented mainly by oxygenated monoterpenes (64.01–71.4%), monoterpene hydrocarbons (21.73–29.92%) and sesquiterpene hydrocarbons (1.47–4.05%). The main components were terpinen-4-ol (29.13–32.57%), cis-sabinene hydrate (19.9–29.27%), trans-sabinene hydrate (3.5–11.61%), γ-terpinene (2.11–8.20%), bornyl acetate (1.52–2.94%) and linalool (1.05–1.39%). On the other hand, phenolic contents varied from 2.706 to 6.834 mg/g of dry weight obtained during the later vegetative stage. RP-HPLC analysis of the methanolic extract of O. majorana L. dried aerial parts showed the predominance of phenolic acids during the early vegetative stage whereas flavonoids predominate during the other stages of growth. The main phenolic acids identified were trans-2-hydroxycinnamic, rosmarinic, vanillic, chlorogenic, gallic and cinnamic whereas the main flavonoids were amentoflavone, apigenin, quercetin, luteolin, coumarin and rutin. Results obtained showed that later vegetative stage is characterized by the highest contents of bioactive compounds and therefore it could be considered as the best stage for harvesting marjoram plants.     

藤茶总黄酮提取物HPLC指纹图谱的研究

目的:建立藤茶总黄酮提取物的HPLC指纹图谱,更有效地监控其质量。方法:采用梯度洗脱法,对藤茶总黄酮提取物进行HPLC测定,流动相为乙腈-10%冰醋酸梯度洗脱,检测波长为270 nm,记录时间为30 min。采用中南大学指纹图谱相似度评价系统软件进行比较计算。结果:运用梯度洗脱能分离藤茶总黄酮提取物的各种成分,通过相似度评价比较,藤茶总黄酮提取物的指纹图谱相似度均大于0.90。结论:此法可作为藤茶总黄酮提取物的指纹图谱,有助于藤茶总黄酮提取物的质量控制。     

CO2倍增对霍山石斛光合特性和生长的影响

为评估CO₂倍增对霍山石斛光合特性和生长的影响,本研究以霍山石斛幼苗为试材,比较了CO₂浓度400 μmol/mol（大气浓度,对照组）和800 μmol/mol（处理组）栽培180 d对霍山石斛光合特性、生长和有效成分的影响。结果表明,CO₂倍增处理显著提高了霍山石斛的净光合速率（P_n）、气孔导度（G_s）、蒸腾速率（T_r）和水分利用率（WUE）,但霍山石斛未出现“光合适应”现象。栽培30 d后,处理组的存活率、着根率和新芽数始终显著高于对照组,而60 d后,处理组的叶片可溶性蛋白含量显著低于对照组。栽培180 d后,CO₂倍增处理组显著提高了霍山石斛的茎鲜重、茎干重、茎长、单株叶片数和叶片厚度,而对茎粗和单叶面积无显著影响。同时,处理组也显著提高了茎的多糖含量,比对照组提高94%,但生物碱含量则显著下降。茎的总氨基酸含量与总黄酮含量在两组间无显著差异。综上,CO₂倍增处理能显著促进霍山石斛的生长,提高成活率及其主要药用部位茎的产量和多糖含量。