富硒玉米子粒中硒赋存形态研究

研究了富硒玉米子粒中硒的分布规律和赋存形态。结果表明,在供试玉米中,硒主要以有机结合态的形式存在,其含量占总硒的比例接近90%;在有机态硒中蛋白质硒含量较高,多糖中硒的含量较低;在蛋白质硒中以碱溶蛋白质中硒的含量为最高,占总硒的50.62%。因此,在富硒玉米的深度开发中,碱溶的弱酸性组分适用于深加工,成为补硒食品或添加剂。     

Selenium Accumulation and Antioxidant Status of Rice Plants Grown on Seleniferous Soil from Northwestern India

Greenhouse experiment was conducted to investigate selenium accumulation and its antioxidant response in two rice varieties(PR116 and Pusa Basmati 1121) grown on normal and seleniferous soils. The plant growth was reduced at early developmental stages and flowering was delayed by a period of 10 d on seleniferous soil. Selenium accumulation increased by 3–20 and 13–14 folds in leaves, 18 and 3 folds in grains from Pusa Basmati 1121 and PR116 varieties, respectively. Selenium accumulation in leaves from rice plants grown on seleniferous soil resulted in significant increase in chlorophyll content, hydrogen peroxide, proline, free amino acids, total phenol and tannin contents. Lipid peroxidation levels and peroxidase activities in leaves increased whereas catalase activity showed a reverse trend. It is concluded that selenium accumulation decreased dry matter content in rice during crop development but these plants were able to combat selenium toxicity by inducing alterations in their defense system.     

寒地水稻叶龄诊断植保技术研究简报

<正>黑龙江省农垦科学院水稻研究所研究员及黑龙江省八一农垦大学植物科技学院研究生,在寒地水稻“三化”栽培理论的基础上,提出寒地水稻叶龄诊断植保技术,改变过去农民靠经验施肥和防治病虫草害,使农民逐渐从过去的老方法(看日历)中解脱出来,按照水稻叶龄生育进程进行施肥和防治病虫草害等。     

寒地水稻叶龄诊断植保技术研究简报

黑龙江省农垦科学院水稻研究所研究员及黑龙江省八一农垦大学植物科技学院研究生,在寒地水稻“三化”栽培理论的基础上,提出寒地水稻叶龄诊断植保技术,改变过去农民靠经验施肥和防治病虫草害,使农民逐渐从过去的老方法（看日历）中解脱出来,按照水稻叶龄生育进程进行施肥和防治病虫草害等.     

Aluminium-tolerant regenrants from potato cell cultures

Summary Cell cultures were developed from dihaploid clones ofSolanum tuberosum L. Selection in cell suspensions as well as plating of cells on selective medium supplemented with 5 mmol Al produced tolerant cell lines. The constancy of Al-tolerance of cell lines was confirmed by culturing the calli for 3 months in Al-free medium and then transferring them back to selective medium. 4 tolerant regenerant clones were obtained which maintained Al-tolerance also after subculture in control medium. Two of the 4 clones that constantly maintained Al-tolerance, originated from cell lines subcultured for 5 months under stress conditions. However, the regeneration rate of these cell lines was low compared with that of lines obtained after a shorter selection period.     

Effectiveness of solar blinkers as a means of crop protection from wild boar damage

The population density of wild boar (Sus scrofa) in Northern Switzerland has increased dramatically during the last three decades and the species has become a major threat to agriculture, causing severe damage to crops and grassland. Vulnerable fields have to be protected from wild boar incursion, which is in most cases achieved by using electric fences. Alternatively, deterrents basing on optical, acoustical or gustative effect are available. The effectiveness of most of these systems has not previously been scientifically tested in the field. In our study we investigated the effectiveness of solar blinkers at baited luring sites. We conducted field experiments at 4 different sites with free-ranging wild boars from January 2007 to January 2008. Data from 504 inspections of the luring sites indicate that solar blinkers reduced the probability of wild boar visits at the luring sites by 8.1% compared to the control sites. We therefore evaluate deterrence effect of solar blinkers to be insufficient for effective crop protection. Probability of wild boar visits at the luring sites changed throughout the study period, showing seasonal variation of the extent of wild boar activity in the fields.     

Integration of acibenzolar-S-methyl with antibiotics for protection of pear and apple from fire blight caused by Erwinia amylovora

Orchard experiments on integration of acibenzolar-S-methyl (ASM) with antibiotics for protection of pear and apple from fire blight were conducted in the west coast region of the United States over a period of 5 years. In 11 pathogen-inoculated trials, a single treatment of streptomycin or oxytetracycline provided an average of 84 and 60% disease control, respectively. The addition of one or two treatments of acibenzolar-S-methyl (ASM) to the single antibiotic program contributed an additional 6 and 11% disease control, respectively, for both antibiotic materials. Among trials, ASM treatment timings were varied from early to late bloom but an effect of timing on disease control could not be determined. In mature commercial pear orchards, ASM treatments at full bloom and petal fall were superimposed onto the grower’s antibiotic program used in each orchard. For the 15 orchards with fire blight, the ASM-treated plots showed 38% fewer infections than adjoining plots that received antibiotic program only. When integrated with antibiotics, ASM provides added disease suppression to fire blight control programs, but the modest degree of protection provided will likely limit its use to high disease risk situations, which includes orchards with a previous disease history, and those planted recently to highly susceptible cultivars.     

Plant regeneration from cell suspension culture of potato (Solanum tuberosum L.)

In the present study, for callus production leaf and stem segments of potato cultivar White Desiree were cultured on MS medium supplemented with 2,4-D, NAA and Kinetin (callus production medium). Calli then were transferred in the same liquid medium for cell suspension production. In the next step cell suspensions were transferred back to the callus production medium. Finally, calli derived from cell suspension were cultured on 6 different shoot initiation media (S1-S6). However, on S6 medium with combination of GA3 and BAP more than 80% of the calli produced shoot buds and shoots. Fully grown shoots then were rooted and produced whole plants. Chromosome and morphological analysis showed no somaclonal variation among regenerated plants.     

Lipid removal enhances separation of oat grain cell wall material from starch and protein

Effects of lipid removal on the fine milling and air classification processing of oats were studied. Lipid removal by supercritical carbon dioxide (SC-CO₂) extraction enabled concentration of the main components of oats - starch, protein, lipids and cell walls - into specific fractions. Using defatted oats as raw material, the highest β-glucan concentration of the cell wall-enriched fraction was 33.9% as compared to 17.1% without lipid removal. This was probably due to more efficient milling yielding smaller particles, and release of starchy material from cellular structures during milling of defatted oats, resulting in better classification. The removal of lipids also enabled separation of an oat protein concentrate with a protein concentration of 73.0% and a mass yield of 5.0%. A trial with 2310 kg of oat groats showed that the process based on defatting and dry fractionation was also industrially applicable.     

Agronomic traits and RAPD analysis of two mutants derived from rice somatic cell culturing

Genetic variation, including agronomic trait variation, often occurs in somatic cell culturing. In this study, we compared the main agronomic traits of two rice mutants, M3 and M14, which were derived from Shenxiangjing 5 somatic cell culturing. Significant differences were found between the two mutants and the wild rice Shenxiangjing 5 (Table 1). Results were as follows:     

Anti-proliferative activity of meroditerpenoids isolated from the brown alga Stypopodium flabelliforme against several cancer cell lines

The sea constitutes one of the most promising sources of novel compounds with potential application in human therapeutics. In particular, algae have proved to be an interesting source of new bioactive compounds. In this work, six meroditerpenoids (epitaondiol, epitaondiol diacetate, epitaondiol monoacetate, stypotriol triacetate, 14-ketostypodiol diacetate and stypodiol) isolated from the brown alga Stypopodium flabelliforme were tested for their cell proliferation inhibitory activity in five cell lines. Cell lines tested included human colon adenocarcinoma (Caco-2), human neuroblastoma (SH-SY5Y), rat basophilic leukemia (RBL-2H3), murine macrophages (RAW.267) and Chinese hamster fibroblasts (V79). Antimicrobial activity of the compounds was also evaluated against Staphylococcus aureus, Salmonella typhimurium, Proteus mirabilis, Bacillus cereus, Enterococcus faecalis and Micrococcus luteus. Overall, the compounds showed good activity against all cell lines, with SH-SY5Y and RAW.267 being the most susceptible. Antimicrobial capacity was observed for epitaondiol monoacetate, stypotriol triacetate and stypodiol, with the first being the most active. The results suggest that these molecules deserve further studies in order to evaluate their potential as therapeutic agents.     

Effect of Schlafen 2 on natural killer and T cell development from common T/natural killer progenitors

Natural Killer (NK) cells are thought to develop from common lymphoid progenitors in the bone marrow. Even though thymus is not essential for NK cell development, T-cell/natural killer-cell (T/NK) precursors, DN1 (CD44+CD25-) and DN2 (CD44+CD25+) when cultured on an OP9 stroma, give rise to some NK1.1 cells. Genes of the Schlafen (Slfn) family are involved in hematopoietic and immune processes. The contribution of the Slfn genes in NK cell development from Double Negative (DN) cells is unknown. We transduced DN1 and DN2 progenitors prepared from C57BL/6 (B6) mouse thymus with Schlafen 1 (Slfnl) and Schlafen 2 (Slfn2) genes using Mig retroviral vector containing the Green Fluorescent Protein (GFP) gene and cultured those transduced progenitors on OP9 and OP9 stroma expressing the Notch ligand Delta-like 1 (OP9-DL 1) with appropriate cytokines to see if they affect generating NK and T-cells differently. Maturation of both NK and T cells from immature T/NK thymocytes hampered by Slfn1 and Slfn2 transduction but we got a small number of Slfn1 and Slfn2 expressing cells upon culture of transduced DN progenitors on stroma cells. There was no difference between Slfn1 expressing (GFP+) and none expressing T cells regarding CD3 expression but all mature NK cells were from Slfn1 negative population. Slfn2 completely blocked maturation of T cells but there was no difference between Slfn2 expressing and none expressing NK cells. Based on our findings both Slfn1 and Slfn2 interfere with maturation of DN2 progenitors but T cell development is more sensitive to Slfn2 expression than NK cell.     

A lactose-binding lectin from the marine sponge Cinachyrella apion (Cal) induces cell death in human cervical adenocarcinoma cells

Cancer represents a set of more than 100 diseases, including malignant tumors from different locations. Strategies inducing differentiation have had limited success in the treatment of established cancers. Marine sponges are a biological reservoir of bioactive molecules, especially lectins. Several animal and plant lectins were purified with antitumor activity, mitogenic, anti-inflammatory and antiviral, but there are few reports in the literature describing the mechanism of action of lectins purified from marine sponges to induce apoptosis in human tumor cells. In this work, a lectin purified from the marine sponge Cinachyrella apion (CaL) was evaluated with respect to its hemolytic, cytotoxic and antiproliferative properties, besides the ability to induce cell death in tumor cells. The antiproliferative activity of CaL was tested against HeLa, PC3 and 3T3 cell lines, with highest growth inhibition for HeLa, reducing cell growth at a dose dependent manner (0.5-10 μg/mL). Hemolytic activity and toxicity against peripheral blood cells were tested using the concentration of IC(50) (10 μg/mL) for both trials and twice the IC(50) for analysis in flow cytometry, indicating that CaL is not toxic to these cells. To assess the mechanism of cell death caused by CaL in HeLa cells, we performed flow cytometry and western blotting. Results showed that lectin probably induces cell death by apoptosis activation by pro-apoptotic protein Bax, promoting mitochondrial membrane permeabilization, cell cycle arrest in S phase and acting as both dependent and/or independent of caspases pathway. These results indicate the potential of CaL in studies of medicine for treating cancer.     

Composition and molecular structure of polysaccharides released from barley endosperm cell walls by sequential extraction with water,malt enzymes,and alkali

Isolated and purified endosperm cell walls (CW), used in this study, were derived from a Canadian malting barley variety, AC Metcalfe, grown in three different environments in Canada in 2003, and varying in grain protein and β-glucan contents, as well as in grain hardness. The CW were initially extracted with water at 45 °C and subsequently digested with barley malt crude enzyme extract resulting in two fractions designated CW-WE45 and CW-MD, respectively. The remaining non-digested cell wall material (CW_ND) was further fractionated by sequential extraction with water at 95 °C (CW_ND-WE95), saturated barium hydroxide (CW_ND-BaE), and 1 N sodium hydroxide (CW_ND-NaE) at 25 °C. Composition and molecular structure analyses were carried out for all fractions including the remaining cell wall residue (CW_RES). Extraction of CW with water followed by digestion with malt crude enzyme extract solubilized the majority of β-glucans (∼55–70%) and glucomannans (∼60–80%) but only a small portion of arabinoxylans (∼20–30%) present in the intact CW. The CW-WE45 and CW_ND-WE95 fractions consisted mostly of β-glucans exhibiting high average molecular weights (M_w) (2–3 × 10⁶), whereas the CW_ND-BaE consisted mainly of arabinoxylans with M_w about 1–1.5 × 10⁶. The CW_ND-NaE contained almost equal amounts of β-glucans and arabinoxylans and a small amount of glucomannans, whereas the CW_RES contained approximately equal proportions of β-glucans, arabinoxylans and glucomannans. β-Glucans in CW_ND-WE95, CW_ND-NaE, and CW_RES exhibited a higher ratio of 3-O-β-d-cellobiosyl-d-glucose to 3-O-β-d-cellotriosyl-d-glucose (DP3/DP4) compared to β-glucans in CW-WE45 and CW-MD. β-Glucans in CW_ND-NaE showed the highest level of long cellulosic oligosaccharides with DP ≥ 5, whereas those in the CW_RES had the highest DP3/DP4 ratio. The CW-MD was fractionated by ultrafiltration into high (CW-MD_HMW) and low-molecular weight (CW-MD_LMW) sub-fractions, with weight-average M_w of ∼150–350 × 10³ and <10 × 10³, respectively, as confirmed by size-exclusion chromatography. The monosaccharide composition of the sub-fractions indicated a more extended enzymic degradation of β-glucans and glucomannans than arabinoxylans. Some differences in composition and molecular structure of the cell wall constituents among the three barley samples were related to their solubility and enzymic digestibility.     

Screening and quantification of an antiseptic alkylamide, spilanthol from in vitro cell and tissue cultures of Spilanthes acmella Murr.

The study revealed, for the first time, accumulation of spilanthol, an antiseptic alkylamide, in in vitro cultures of Spilanthes acmella Murr., a medicinal plant of immense commercial value. To achieve this, in vitro shoots were regenerated via direct organogenesis from leaf-disc explants of Spilanthes. Shoots were induced in the presence of N⁶-benzylaminopurine (BAP) alone or in combination with either α-naphthalene acetic acid (NAA) or Indole-3-acetic acid (IAA) in Murashige and Skoog medium. The best treatment for shoot regeneration was MS + BAP (5.0 μM) + IAA (5.0 μM), which promoted adventitious shoot proliferation in >82% cultures with an average of 5.3 shoots per explant. Regenerated shoots rooted spontaneously with a frequency of 100% on half strength MS medium (major salts reduced to half strength) containing 50 g l⁻¹ sucrose. The plantlets were acclimatized successfully with 90% survival rate. Additionally, ploidy stability of the regenerated plants was assessed by flow cytometry which showed that all investigated plants had the similar ploidy as that of the mother plant. For spilanthol identification, peaks eluted from HPLC were analyzed by mass spectrometry with its characteristic fragmentation pattern. For quantification studies, calibration curve was generated, which revealed a higher amount of spilanthol content (3294.36 ± 12.4 μg/g DW) in the leaves of in vitro plants compare to those of in vivo plants (2703.66 ± 9.6 μg/g DW of spilanthol). An efficient multiplication frequency, ploidy stability and enhanced spilanthol accumulation ensure the efficacy of the protocol developed for this industrially important medicinal plant.     

G1 phase arrest and apoptosis induction in human thyroid cancer cell line Thr.C1.PI33 by 3-hydrogenkwadaphnin isolated from Dendrostellera lessertii

BACKGROUND: Dendrostellera lessertii (Thymelaeaceae) is a toxic plant that grows in parts of Iran. The anti-proliferative properties of its crude methanol extract and one of its active components, 3-hydrogenkwadaphnin (3-HK), have been established using several cancer cell lines. METHODS: In a further attempt to determine the mode of action, two groups of synchronously growing cells were treated with a single dose of 3-HK (3.5 nM) and/or a single dose of the crude extract (equivalent to 0.36 mg plant powder). Every 8 hours, the percentages of cells within G1, S, and G2-M phases were determined by flow cytometric (FCM) analysis; electron microscopic pictures were taken after fixation with 2% glutaraldehyde. RESULTS: Twelve hours after treatments, apoptotic cell death was confirmed by the observation of marked morphological changes of the plasma membrane as microvillar disappearance and the appearance of apoptotic bodies in the treated cells. FCM analyses revealed that the G1 phase arrest was under the influence of the pure substance. CONCLUSION: The results confirmed the previously drawn conclusion that the raw material and the pure substance from D. lessertii exert their anti-tumor effects through cell cycle arrest at G1 phase and diversion of cell fate toward programmed cell death.