Production of Lectins from Marine Algae: Current Status,Challenges, and Opportunities for Non-Destructive Extraction

Marine algae are an excellent source of novel lectins. The isolation of lectins from marine algae expands the diversity in structure and carbohydrate specificities of lectins isolated from other sources. Marine algal lectins have been reported to have antiviral, antitumor, and antibacterial activity. Lectins are typically isolated from marine algae by grinding the algal tissue with liquid nitrogen and extracting with buffer and alcohol. While this method produces higher yields, it may not be sustainable for large-scale production, because a large amount of biomass is required to produce a minute amount of compound, and a significant amount of waste is generated during the extraction process. Therefore, non-destructive extraction using algal culture water could be used to ensure a continuous supply of lectins without exclusively disrupting the marine algae. This review discusses the traditional and recent advancements in algal lectin extraction methods over the last decade, as well as the steps required for large-scale production. The challenges and prospects of various extraction methods (destructive and non-destructive) are also discussed.     

Salivary cortisol in pigs following adrenocorticotrophic hormone stimulation: comparison with plasma levels

Four prepubertal pigs were prepared with venous catheters and housed in metabolism cages. Plasma and saliva samples were taken at 15-min intervals over a 105-min period and analysed by radioimmunoassay for total (i.e. free and bound) cortisol content. Adrenocorticotrophic hormone (ACTH) was given i.v. at three different doses (0.5, 1.0 and 2.0 mg) after the second sample and the cortisol responses were compared with pretreatment values and levels observed after saline vehicle administration. Basal levels of salivary cortisol were approximately 10% of those in plasma. ACTH induced significant increases in plasma and salivary cortisol but in no case was a dose/response relationship detected. Plasma cortisol showed a maximum increase of approximately 230% whereas salivary cortisol increased only by about 130%, indicating that salivary cortisol is a less sensitive indicator of adrenal activity than plasma cortisol in this species. Estimation of salivary cortisol concentrations may offer practical advantages for the assessment of stress responses in intensively housed pigs.     

金荞麦对脂多糖诱导小鼠小肠炎症的保护作用

为探究金荞麦对脂多糖（LPS）诱导的小鼠小肠炎症的保护作用,试验使用雌性ICR小鼠,前期14 d饮水添加不同浓度金荞麦和阳性对照品——芦丁（Rutin）,随后腹腔注射LPS（10 mg/kg）构建小肠急性炎症模型,通过观察小鼠行为变化、血常规检测、组织切片和炎症相关基因定量检测等评估效果。结果发现,腹腔注射10 mg/kg的LPS可成功诱导小鼠急性肠炎;添加金荞麦能够剂量依赖性地降低LPS诱导的肠炎小鼠体重损失。血常规检测显示,腹腔注射LPS后导致小鼠血液白细胞数（WBC）、红细胞数（RBC）、血红蛋白（HGB）、血小板数目（PLT）显著下降,添加金荞麦或芦丁能一定程度缓解由于LPS引起的血常规异常。小肠切片HE染色结果显示,腹腔注射LPS后小肠固有层中间出现大量灶性的炎性细胞浸润,腺上皮可见少量的炎性细胞浸润,肠道细胞排列紊乱,可见核分裂及核碎裂,同时黏膜充血、出血严重;添加金荞麦或芦丁能一定程度抑制炎性细胞浸润和黏膜出血。实时荧光定量PCR结果显示,腹腔注射LPS能显著促进小肠促炎性因子IL-6、TNF-α和IL-1β的表达,添加金荞麦能剂量依赖性下调TNF-α和IL-1β的表达水平。以上结果表明饮水添加金荞麦和芦丁可以有效缓解LPS诱导的小鼠小肠炎症,金荞麦浓度为12%的添加剂量在部分指标上可达到或接近灌胃100 mg/kg芦丁的效果。     

论河南省公路绿化植物选择

河南省境内交通发达、公路纵横,其公路绿化得天独厚、大有可为。河南省公路绿化植物的选择,应遵循交通安全、生态优先、因地制宜、多重效益兼顾、生物多样性几项原则,并且依中央隔离绿化带、快慢道隔离绿化带、路肩绿化带、边坡绿化带、边沟绿化带、主绿化带这些不同地段的立地条件和绿化要求,来选择相应的植物种类。     

Changes in pig salivary cortisol in response to transport simulation, food and water deprivation, and mixing

Cortisol concentrations in the saliva of two groups (N = 5/group) of prepubertal pigs were measured by radioimmunoassay. Samples were collected in the home pen under normal husbandry conditions and after a 24 h period when food and water were withheld. The pigs were then transferred to a transport simulator, which was left stationary (control) or set in motion (experimental), and further samples were taken 1 h later before the animals returned to their pens. In the following week, the two groups of pigs were mixed and saliva was collected over a 3 h period. Samples were also taken 2 days later after the pigs had been injected with a maximally stimulating dose of adrenocorticotrophin (ACTH). Transport simulation in deprived animals, and mixing, produced salivary cortisol levels similar to those seen after ACTH. Food and water deprivation alone also increased cortisol secretion whereas transport simulation in non-deprived animals had no effect. These results indicate that salivary cortisol estimation offers a non-invasive means of measuring stress responses in unrestrained pigs.     

Combining process-based models for future biomass assessment at landscape scale

We need an integrated assessment of the bioenergy production at landscape scale for at least three main reasons: (1) it is predictable that we will soon have landscapes dedicated to bioenergy productions; (2) a number of “win–win” solutions combining several dedicated energy crops have been suggested for a better use of local climate, soil mosaic and production systems and (3) “well-to-wheels” analyses for the entire bioenergy production chain urge us to optimize the life cycle of bioenergies at large scales. In this context, we argue that the new generation of landscape models allows in silico experiments to estimate bioenergy distributions (in space and time) that are helpful for this integrated assessment of the bioenergy production. The main objective of this paper was to develop a detailed modeling methodology for this purpose. We aimed at illustrating and discussing the use of mechanistic models and their possible association to simulate future distributions of fuel biomass. We applied two separated landscape models dedicated to human-driven agricultural and climate-driven forested neighboring patches. These models were combined in the same theoretical (i.e. virtual) landscape for present as well as future scenarios by associating realistic agricultural production scenarios and B2-IPCC climate scenarios depending on the bioenergy type (crop or forest) concerned in each landscape patch. We then estimated esthetical impacts of our simulations by using 3D visualizations and a quantitative “depth” index to rank them. Results first showed that the transport cost at landscape scale was not correlated to the total biomass production, mainly due to landscape configuration constraints. Secondly, averaged index values of the four simulations were conditioned by agricultural practices, while temporal trends were conditioned by gradual climate changes. Thirdly, the most realistic simulated landscape combining intensive agricultural practices and climate change with atmospheric CO₂ concentration increase corresponded to the lowest and unwanted bioenergy conversion inefficiency (the biomass production ratio over 100 years divided by the averaged transport cost) and to the most open landscape. Managing land use and land cover changes at landscape scale is probably one of the most powerful ways to mitigate negative (or magnify positive) effects of climate and human decisions on overall biomass productions.     

Influences of recovery from clear-cut, climate variability, and thinning on the carbon balance of a young ponderosa pine plantation

From 1999 to 2002, the variations in carbon flux due to management practices (shrub removal, thinning) and climate variability were observed in a young ponderosa pine forest originated from clear-cutting and plantation in 1990. These measurements were done at the Blodgett Forest Ameriflux site located in the Sierra Nevada Mountains of California. Thinning in spring 2000 decreased the leaf area index (LAI) by 34% and added 496 g C m⁻² of wood and leaf debris at the soil surface. Total ecosystem respiration was not significantly affected by thinning (1261 g C m⁻² in 1999 and 1273 g C m⁻² in 2000), while canopy photosynthesis decreased by 202 g C m⁻². As a result the ecosystem shifted from a net sink of CO₂ in 1999 (−201 g C m⁻²) to a small net source in 2000 (13 g C m⁻²). Woody and leaf debris resulting from thinning only accounted for maximum 1% and 7% of the total respiration flux, respectively. Thinning did not affect the relative proportion of the different components of respiration to an observable degree. Low soil water availability in summer 2001 and 2002 decreased the proportion of soil respiration to the total respiration. It also imposed limitations on canopy photosynthesis: as a result the ecosystem shifted from a sink to a source of carbon 1 month earlier than in a wetter year (1999). The leaf area index and biomass of the stand increased rapidly after the thinning. The ecosystem was again a sink of carbon in 2001 (−97 g C m⁻²) and 2002 (−172 g C m⁻²). The net carbon uptake outside the traditionally-defined growing season can be important in this ecosystem (NEE = −50 g C m⁻² in 2000), but interannual variations are significant due to differences in winter temperatures.     

An open circuit respirometer for metabolic studies on the domestic fowl: establishment of standard operating conditions

Details of an open circuit respirometer that allows continuous specific measurements of gaseous exchange by the fowl are given.

“ Basal” oxygen consumption of the laying hen decreases by 20% during the first 3 d of training to the experimental situation. Thereafter it remains constant.

The time required to reach the post‐absorptive state was found to be 24 h for birds weighing less than 2.5 kg and 48 h for those weighing more than 2.5 kg. The mean basal metabolic rate (BMR) of adult laying hens was 11.3 ml O₂/kg/4> min and the mean RQ was 0.709.     

彩叶南天竹新品种引进及抗逆性研究

通过对从美国引进的彩叶南天竹品种的栽培管理、性状观察及适应性、抗逆性等方面研究,结果表明新引进的南天竹品种具有生长良好、性状表现突出、适应性抗逆性强等特点。     

Seasonality of photosynthetic parameters in a multi-specific and vertically complex forest ecosystem in the Sierra Nevada of California

Understanding seasonal variations of photosynthetic parameters is critical for accurate modeling of carbon dioxide (CO2) uptake by ecosystems. Maximum carboxylation velocity (Vcmax), maximum rate of electron transport (Jmax), leaf respiration in the light (R(day)), light-saturated assimilation (Amax) and maximum quantum yield (Phi) were calculated from leaf gas exchange measurements made monthly throughout the year on leaves of three co-occuring evergreen species in a Pinus ponderosa Dougl. ex P. Laws. & C. Laws. forest with shrubs in the understory (Arctostaphylos manzanita Parry and Ceanothus cordulatus Kellogg.). The seasonality and relationships of the photosynthetic parameters with environmental and physiological variables differed among the species. The nitrogen-fixing species, C. cordulatus had the highest values of the parameters and the largest seasonal variation, whereas A. manzanita exhibited the lowest seasonality and weaker correlations with environmental variables. In general, variations in Vcmax were highly correlated with light, leaf mass per area and leaf nitrogen content on an area basis. Temporal scaling of the parameters with each other seemed possible for C. cordulatus and P. ponderosa. However, lags between these variables and Vcmax likely reflect the influences of other factors. The acclimation relationships found along vertical light gradients within canopies in other studies cannot be applied to seasonal variations. The Jmax to Vcmax ratio varied seasonally for P. ponderosa and A. manzanita, being lower at high light, high air temperature and low soil water content.