灵芝三萜和多糖提取工艺研究

采用醇提法、水提法分别提取灵芝三萜和多糖,并与超声波辅助提取效果进行比较。结果,灵芝三萜的最佳提取条件为：采用10倍无水乙醇,在60℃提取60 min,提取2次,三萜提取率为0.76%;灵芝多糖的最佳提取条件为：用90℃热水提取90 min,料（g）液（mL）比1∶20,提取2次,多糖提取率为2.67%。超声波辅助提取,灵芝三萜和多糖的提取率可分别提高20.5%和13.2%。     

破壁灵芝孢子粉的制备及免疫活性研究

通过比较不同的破壁技术对灵芝孢子破壁率及有效成分溶出的影响,以期建立灵芝孢子的高效破壁工艺,并考察破壁灵芝孢子粉对小鼠免疫功能的影响。结果表明,采用超微粉碎破壁法,破壁时间30 min,破壁率达到96.97%,总三萜和总多糖的溶出量分别为34.16 mg/g和33.88 mg/g,比对照分别提高了160.2%和390.0%。此外,与未破壁灵芝孢子粉比较,破壁灵芝孢子粉的免疫活性显著增强,显著减轻小鼠脾脏的损伤,延缓迟发型变态反应,增加单核-巨噬细胞吞噬功能和血清溶血素的含量。     

不同灵芝提取液含量对冲剂颗粒质量的影响

试验设计4种提取方法:水煮、醇提、先水煮后醇提、先醇提后水煮,研究不同提取方法对灵芝(Ganoderma lucidum)活性成分的影响;设置辅料(kg)和灵芝提取液(L)的配比为8:1、10:1、12:1、14:1、16:1,通过测定颗粒成型性、堆密度、停止角、溶化率、吸湿性,研究不同灵芝提取液含量对灵芝冲剂质量影响。结果显示:灵芝多糖和蛋白含量高低的顺序均为先醇提后水煮先水煮后醇提水煮醇提,而灵芝三萜的顺序为先水煮后醇提先醇提后水煮醇提水煮。综合考虑先醇提后水煮和先水煮后醇提的方法最佳;除8∶1配比颗粒成型性不达标外,其余所有处理的所有指标均符合标准,效果最佳的配比为10∶1,本试验为灵芝颗粒冲剂的加工技术提供参考数据。     

灵芝孢子破壁前后在模拟人体消化环境中活性成分的差异

目的：研究灵芝孢子在破壁前后,其内的灵芝三萜和灵芝多糖在人体消化系统内的差异。方法：采用模拟人体消化环境,用香草醛-高氯酸法[1]和蒽酮-硫酸法[2]检测孢子内的三萜和多糖含量。结果：孢子在破壁前后的三萜含量分别为0.29%和5.94%,多糖含量则分别为10.29 mg/g和11.44 mg/g;人工胃液处理的环境下,释放到人工胃液内的破壁孢子多糖含量大于未破壁孢子（0.98 mg/mL>0.62 mg/mL）;沉淀再经过人工肠液的处理后,人工肠液的多糖均未检出。破壁孢子沉淀的三萜含量大于未破壁孢子（6.68%>1.58%）,结论：灵芝孢子破壁后其有效成分更易于在人体消化环境内释放。     

不同生长期灵芝子实体三萜酸和多糖含量测定

分别采用HPLC法和药典法测定不同生长期灵芝子实体中三萜酸和灵芝多糖的含量。HPLC法色谱条件:色谱柱为Alltech Alltima C_(18)柱(150 mm×4.6 mm,5μm),流动相为乙腈-0.04%甲酸溶液,检测波长254 nm,流速1.0 m L/min,柱温15℃。结果:灵芝酸C_2、灵芝酸G、灵芝烯酸B、灵芝酸B、灵芝烯酸A、灵芝酸A、灵芝酸D、灵芝烯酸D和灵芝酸C_1的线性范围为5.9~42.0μg/m L,r为0.999,加样回收率为96.42%~104.14%。表现方法可行、重现性好,能定量测定灵芝中三萜酸和多糖的含量。     

蒸汽爆破处理灵芝饮片的工艺优化及品质分析

以灵芝子实体为原料,通过蒸汽爆破技术对灵芝饮片茶进行工艺优化。以不同参数处理灵芝饮片,将灵芝粗多糖溶出率和感官得分作为考核指标,优化得到蒸汽爆破预处理灵芝饮片的最佳工艺条件,并对处理前后粗多糖的体外抗氧化能力进行比较。结果显示,以粗多糖溶出率为考核指标,得到最佳工艺为样品含水量20%、压强0.7 MPa、时间75 s,此时灵芝粗多糖溶出率为0.473 6%,较未经处理的灵芝饮片提高43.51%。以感官评分为指标,得到最佳工艺参数为样品含水量30%、压强0.6 MPa、时间75 s,此时感官评分为92分。同时,经过处理的灵芝饮片粗多糖的DPPH·清除率IC₅₀为0.32 mg·mL^-1,与未经处理的传统灵芝饮片相比提高12.5%。     

不同浓度乙醇对灵芝功能成分浸出率的影响

借助硅胶薄层平板色谱测定方法探索了不同浓度乙醇溶液对灵芝多糖和三萜溶出效果的影响。结果表明,三萜类成分溶出率与乙醇浓度呈正相关,75°乙醇浸提液中三萜成分含量是30°乙醇浸提液的2倍;浸提液中多糖含量随乙醇浓度提高而降低,30°乙醇浸提液中多糖含量是75°乙醇浸提液的2.9倍。     

灵芝品种子实体多糖和三萜含量分析与评价

为了选育加工专用型灵芝品种,以灵芝多糖和三萜含量为评价指标,对12个灵芝品种的子实体多糖和三萜含量进行了分析评价.结果表明,不同灵芝菌株的子实体在多糖和三萜含量上存在着一定的差异,其中多糖以薄树灵芝、日本红芝、仙芝、京大、树舌灵芝含量高,三萜含量却以京大、赤芝05、惠州、信州、树舌灵芝、松杉灵芝、日本红芝含量高,并且二者的含量不存在显著的相关性,这为选育灵芝多糖、灵芝三萜含量均高,并适合精深加工专用的灵芝品种提供了理论依据.     

灵芝破壁孢子粉功效成分提取条件优化及去壁全溶高含量孢子粉的制备

以破壁灵芝孢子粉为原材料,通过提取、分离、浓缩、喷雾干燥制得一种去壁全溶高含量灵芝孢子粉,采用单因素实验研究溶剂乙醇添加量、提取温度、提取时间对多糖和三萜含量的影响,并通过正交试验优化工艺条件,结果为:影响多糖和三萜含量高低的因素依次为溶剂中乙醇添加量>提取温度>提取时间;综合分析得到提取最佳工艺组合为溶剂乙醇添加量10%,提取温度100℃,提取时间3 h(二次提取)。在此条件下制得的去壁全溶灵芝孢子粉多糖含量达到7.79%,三萜含量达到7.76%。     

六种灵芝子实体多糖含量的对比分析

采用超声波辅助热水提取法研究了6种灵芝子实体多糖的含量。结果表明:4号九龙山灵芝子实体多糖含量最高;正交实验所得灵芝子实体多糖最佳超声提取条件为:提取温度70℃、提取时间35 min、料液比1∶40。在精密度试验中,RSD在0.21%～0.61%之间,表明精密度较好;在稳定性试验中,RSD在0.70%～4.63%之间,表明在0～8 h之间的稳定性较好。     

梨组织RNA提取方法研究

借鉴荔枝果实总RNA提取方法,针对梨本身的特点利用改良 Bugos法分别对叶片、花瓣、果肉中总RNA进行提取研究.结果表明:改良Bugos法对梨不同组织中RNA的提取效果较好,花瓣中RNA的相对含量最高,叶片次之,果肉最少.     

A comparison of the combined effect of water stress and crop load on fruit growth during different phenological stages in young peach trees.

Summary

The combined effect of fruit load and water stress on fruit water content and dry-matter accumulation was analysed for three phenological stages of fruit growth. Irrigation treatments were no irrigation during Stage I (NI-SI), Stage II (NI-SII), or Stage III (NI-SIII) compared with a fully irrigated control. Three thinning treatments were imposed within each irrigation treatment resulting in fruit loads ranging from low to high. Fruit harvests at the end of Stage I, II and III were used to determine total tree fruit fresh and dry matter after each stage of fruit development. Fruit water accumulation was highly sensitive to the effect of water stress at high fruit loads in all fruit developmental phases, but reductions in fruit water content were more apparent during Stages II and III than during Stage I. On the other hand, fruit dry-matter accumulation was relatively insensitive to water stress at any fruit load level and developmental stage. However, reductions in dry-matter accumulation were obtained during Stage III from those trees that were not irrigated during Stage I (NISI). Since these reductions occurred only for mid-to-high fruit load conditions, the decreases in fruit growth during Stage III appeared to be related to a carbon source limitation. The possible reasons for this source limitation are discussed.     

Mitigation of severe water stress by fruit thinning in ‘O’Henry’ peach: Implications for fruit quality

Fruit thinning can be used to relieve water stress in peach but it is not known how fruit quality will respond under water limited conditions. To elucidate this, we applied, over the growing seasons of 2003 and 2004, irrigation and fruit thinning treatments to ‘O’Henry’ peach at the onset of Stage III of fruit development. The treatments were full irrigation (FI) and no irrigation (NI) with each receiving three crop load levels: light, commercial and heavy. Fruit size and fruit skin colouration were lower in NI than in FI but the following were higher in NI fruit: firmness, juice titratable acidity and electrical conductivity, and concentrations of dry matter and soluble solids. All the quality parameters were significantly correlated with tree water status, expressed as midday stem water potential. NI fruit matured 5–10 days later than FI fruit. The increased dry matter concentration, juice acidity, and electrical conductivity in NI fruit were indicative of lower quality at harvest. Choosing a light crop load was not effective in improving NI fruit quality except for the size. Since fruit size is the most important fruit quality attribute, its increase might compensate for yield losses resulting from heavy fruit thinning. Nevertheless, when heavy thinning is performed for mitigation of water stress in Stage III, the overall fruit quality will suffer if severe water stress is inevitable because of shortage or lack of irrigation water.     

果树水分亏缺指标的探讨

探讨了以叶片水势((?)_L)、气孔阻力(Rs)、蒸腾速率(Tr)作为果树水分亏缺指标的可行性.结果表明:黎明前(?)_L与上午10时左右的净光合速率(Pn)Tr以及果实直径、土壤水分含量明显相关;晴朗天气下,上午10时左右的Rs、Tr对水分亏缺反应明显,与(?)_L、Pn、果实直径增长、土壤含水量明显相关.三个指标较好地反映出与树体水分亏缺相联系的生理过程及土壤含水量,可作为评估树体水分状况适宜程度的良好指标.研究也证明:相同条件下,树体各部分三指标的大小不同,根据灌溉应满足树体水分竞争代谢“弱者”的原则,(?)L的取样部位应为树冠上部枝条的下位叶,而Rs、Tr则为内膛无果短梢叶.     

Response of some horticultural crops to irrigation in the semi-arid region of Tunisia

Response to a limited water supply was determined for 3 horticultural crops, pepper, melon (cantaloup) and tomato, in the Nebhana Valley, Tunisia. Varying fractions of potential evapotranspiration (PET), as calculated by Penman, were used to define 4 irrigation treatments which were replicated 4 times. The study was conducted on a shallow sandy loam soil in the lower Nebhana Valley, near Monastir. For each of the crops the following production parameters were evaluated: marketable yield; average fruit weight; number of fruits per unit land area. For socio-political reasons, the cost price of the irrigation water to the farmers in the Nebhana Valley is of negligible importance, and thus the economic threshold could be drawn from the relationship between yield and total available water. The marketable yield for pepper, melon and tomato crops was not significantly affected by rationing the seasonal water application volumes to 57, 47 and 67%, respectively, of the calculated PET. To increase the water-use efficiency for the crops studied, limited irrigation is advisable.     

花菇菌棒新型保水膜应用

以应用较为广泛的石蜡保水膜为对照，比较了三种菌兴保水膜和免割袋对花菇菌棒保水效果、花菇产量和花菇发生率的影响。出菇前保水结果表明，应用菌兴102保水膜的花菇菌棒日均失水量为4．6g，比对照石蜡膜低0．8g，差异达到极显著水平；应用免割袋的花菇菌棒日均失水量为6．8g，比对照石蜡膜高1．4g，差异达极显著水平。应用各种保水膜的干花菇袋单产均可达到70g以上。应用菌兴100、101、102保水膜和免割袋与对照石蜡膜的花菇发生率分别为50．9％、51．0％、54．1％、42．9％和53．7％，差异显著性分析表明，菌兴系列保水膜与石蜡膜的差异不显著，而免割袋与石蜡膜的差异达到了极显著水平。从保水效果、花菇产量、花菇发生率和生产成本来看，菌兴102保水膜可替代石蜡保水膜用于花菇生产，具有广阔的应用前景。     

果实乃日中储水库:一个长期争议的问题(英文)

20世纪初创立的所谓"果实乃日中储水库"的理论,在70—80年代受到了挑战。反对者认为原来理论创立者所采用的是切枝试材而非完整植株,属于试验方法上的错误。他们怀疑切枝试材会迫使形成一种非自然的水势梯度,导致蒸腾的叶片能够从果实获取水分。本文报道氚水示踪法在完整植株上的试验结果,证明果实的水分完全可以被叶片抽走,此外,"去果实"和"留果实"的对比试验证明果实的存在有利于降低叶片在昼间的缺水程度,即叶水势相对较高。作者指出果实在夜间对水分的竞争力往往超过叶片,所以结果多的果树植株反而容易受旱而死。因此,单纯把果实比喻为"储水库",作为科学用语似不恰当。     

妃子笑荔枝早花大果和晚花小果与营养竞争的关系

对同一穗上的妃子笑早花大果和晚花小果的对比研究发现,各时期处于大体相同发育阶段的早花果果实争夺水分和溶质的能力均大于晚花果。14C-蔗糖标记实验更证实早花果比晚花果具有大得多的争夺碳水化合物能力。对矿质营养的吸收差异总体看来,早花果争夺矿质营养的能力明显强于晚花果,具体表现为:果皮中Zn、K、N、Mg和P的含量和果肉中N、K、Zn和Ca含量均是早花果明显大于晚花果。据此认为,早花果的果实大与其具有强大的竞争库力有关;果实中K、Zn和N的水平可能与荔枝大果性状呈明显的正相关。     

Analysis of blueberry (Vaccinium corymbosum L.) fruit water dynamics during growth using an ecophysiological model

Blueberry (Vaccinium corymbosum L.) fruits exhibit three growth stages associated with distinct biological processes. During these periods, water and carbon accumulate in the fruit, determining quality traits such as fruit size and sugar concentration. We adapted the Fishman-Génard model to blueberry and used it to analyse the effect of fruit load on fruit fresh mass and water dynamics, based on empirical observations of dry mass and sugar content performed throughout the fruit growth period. Different fruit load treatments were imposed during two seasons on ‘Brigitta’ blueberry plants growing under different culture systems. Increasing fruit load significantly reduced the fresh mass of the fruits at harvest, but did not affect sugar concentration, which was simulated and validated with a mean error of 7% for fresh mass and 15% for sugar concentration for the tested conditions. The most sensitive model parameters were those related to cell wall extensibility and sugar uptake. The simulations indicated that larger fresh mass of the fruit was mainly caused by increases in water fluxes rather than pressure differences. The model implementation provides the first estimates of a set of parameters which govern blueberry fruit water dynamics from fruit set to harvest.     

调亏灌溉条件下鸭梨营养生长、产量和果实品质反应的研究

调亏灌溉条件下的研究结果表明,无论在1期(萌芽至盛花后25d)还是在2期(盛花后25～80d)进行调亏灌溉,树体营养生长受到显著抑制,新梢长度较对照下降15%～25%,夏季修剪量减少18%～33%,树体叶片的相对含水量显著下降,对成龄叶片叶面积和比叶重的影响差异不显著。各处理其花朵坐果率均大于85%,没有显著抑制果径和果实鲜重的增长。在水分胁迫处理结束时,2期胁迫和1+2胁迫处理果实的可溶性固形物含量、还原糖含量和全K含量显著高于对照,1+2胁迫处理的果径和果实鲜重也受到了显著抑制。在采收时各水分胁迫处理与对照相比,在产量、单果重和果实可溶性固形物含量方面无显著差异。