Wheat-yellow pumpkin composite flour: Physico-functional,rheological, antioxidant potential and quality properties of pan and flat bread

The impact of yellow pumpkin powder (YP) substitution (5, 10, and 15%) on wheat flour's physico-functional, pasting, gel texture, and dough rheology was studied. Moreover, the nutritional, organoleptic properties and bioactivity of the composite pan and pita bread were evaluated. An improved water holding capacity was noticed for the blended flour than for control. The pasting parameters were declined significantly (p < 0.05) with increasing YP. Composite flours presented a softer gel texture in the presence of YP. Reduced water absorption, increased dough development time, and lower stability for combined flour dough. The bread with YP depicted increased protein, fat, fiber, and mineral contents, while a reduced volume and specific volume were noticed for pan bread. YP incorporated 5% and did not compromise pan and pita bread's color and overall acceptability. Additionally, composite bread depicted higher total phenolics with enhanced antioxidant activities at the higher substitution of YP.     

富肌醇南瓜种质资源的创新与利用

采用杂交、回交与定向自交系统选育方法,借助高效液相色谱检测技术,创新育成一批富肌醇南瓜新种质,并利用杂种优势技术,育成富肌醇南瓜新品种一串红。经检测,一串红的肌醇含量达661mg/100g,比普通南瓜品种高出120%以上;多糖含量达45.8mg/g,比普通南瓜品种高出30%以上;葡萄糖含量小于50mg/g,且鲜食品质好,兼具丰产、抗病等优良性状,春秋两季均可栽培,适合糖尿病、高血压、高血脂等人群作为日常食疗保健食品。     

南瓜种子超氧化物歧化酶某些性质的研究

采用NBT光化还原法,分别研究了不同缓冲溶液、pH值、温度及抑制剂等因素对南瓜种子SOD活性的影响,并对其类型进行了鉴定,结果表明:南瓜种子萌芽过程中SOD的合成以Mn-SOD为主,其热稳定性很高,在酸性条件下活性完全丧失,在pH8.0 Na2HPO4-NaH2PO4缓冲溶液下酶活性最高;酶活性容易被β-巯基乙醇抑制,对脲及DMSO有一定的耐受性。     

南瓜果肉色素的提取及稳定性的研究

本文研究了从南瓜果肉中提取色素的方法,并对它的光、热、酸、碱稳定性进行了研究,发现其性质较稳定,且原料来源广泛,提取工艺简单,着色效果好,是食品、医药、化妆品等领域的理想添加剂。     

Salting-in characteristics of globular proteins

Protein solubility, and the formation of various solid phases, is of interest in both bioprocessing and the study of protein condensation diseases. Here we examine the the phase behavior of three proteins (chymosin B, β-lactoglobulin B, and pumpkin seed globulin) previously known to display salting-in behavior, and measure their solubility as a function of pH, ionic strength, and salt type. Although the phase behavior of the three proteins is quantitatively different, general trends emerge. Stable crystal nucleation does not occur within the salting-in region for the proteins examined, despite the crystal being observed as the most stable solid phase. Instead, two types of amorphous phases were found within the salting-in region; additionally, an analog to the instantaneous clouding curve was observed within the salting-in region for chymosin B. Also, protein solutions containing sulfate salts resulted in different crystal morphologies depending on whether Li₂SO₄ or (NH₄)₂SO₄ was used.     

NaCI胁迫下不同南瓜幼苗耐盐性研究

研究了300mmol／L NaCl胁迫对19个不同类型南瓜品种幼苗盐害指数、电解质渗透率、脯氨酸及可溶性糖含量的影响。结果表明,随NaCl胁迫时间延长,南瓜幼苗盐害指数、电解质渗透率、脯氨酸含量和可溶性糖含量均呈升高趋势。盐害指数和电解质渗透率能较好反映南瓜幼苗的耐盐性,可作为南瓜品种耐盐性的筛选指标。在NaCl胁迫下,青栗南瓜（Q1）表现出很强的耐盐性,黑蛮南瓜（H2）和黑籽南瓜（H3）为盐敏感品种,而其他为耐盐性中等品种。     

Ribosome-inactivating proteins in edible plants and purification and characterization of a new ribosome-inactivating protein from Cucurbita moschata

The basic protein fraction of tissue extracts from 40 edible plants inhibited cell-free protein synthesis and released adenine from herring sperm DNA, thus having adenine glycosylase activity. This suggested the presence of ribosome-inactivating proteins (RIPs) in the plant extracts. This indication was further strengthened by the presence of the two activities after a partial chromatographic purification of three extracts, including that from Lycopersicon esculentum (tomato), which had very low activity. From the extract of Cucurbita moschata (pumpkin), the most active one, a glycoprotein of 30,665 Da was purified which had the properties of a RIP, in that (i) it inhibited protein synthesis by a rabbit reticulocyte lysate with IC₅₀ (concentration giving 50% inhibition) 0.035 nM (1.08 ng ml⁻¹) and by HeLa, HT29 and JM cells with IC₅₀ in the 100 nM range, (ii) deadenylated hsDNA and other polynucleotidic substrates, and (iii) depurinated yeast rRNA at a concentration of 0.1 ng ml⁻¹, all values being comparable to those of other RIPs. The C. moschata RIP gave a weak cross-reaction only with an antiserum against dianthin 32, but not with antisera against other RIPs, and had superoxide dismutase, antifungal and antibacterial activities.     

不同品种南瓜POD及PPO同工酶的比较研究

采用垂直平板聚丙烯酰胺凝胶电泳技术,对美洲南瓜（Cucurbita pepo L.）和中国南瓜（C.moschata Duch.）共10个不同栽培品种的过氧化物酶（POD）及多酚氧化酶（PPO）同工酶进行了分析研究,并采用聚类分析法对其亲缘关系进行了比较和分类。结果表明,10个不同品种的南瓜根POD共分离出10条酶带,其中el、e4、e5、e6和e9为2个栽培种所共有;e4、e5、e6分离清晰,可作为2个栽培种的特征酶带;PPO同工酶分离出6条酶带,其中e′1和e′4分离清晰,为2个栽培种所共有。     

Biochemical characterization of the RNA-hydrolytic activity of a pumpkin 2S albumin

A pumpkin 2S albumin with ribonuclease (RNase) activity was purified from pumpkin seeds (Cucurbita sp.) by liquid chromatographic techniques. It manifested potent RNase activity toward baker’s yeast RNA and calf liver RNA, and some polyhomoribonucleotides, including poly(A), poly(U) and poly(C) but not poly(G). Moreover, it was able to hydrolyze total RNA of both animal and plant origins. Ions such as Na⁺, Mg²⁺, Ca²⁺, and Zn²⁺ inhibited its RNase activity. Since RNase activity has not been previously reported in 2S albumins, this work may shed further light on the biological importance of this group of proteins.     

Biochemical systematic,population structure and genetic variability studies among Iranian Cucurbita (Cucurbita pepo L.) accessions,using genomic SSRs and implications for their breeding potential

In this study, SSR markers were used to detect genetic diversity among and within accessions of Cucurbita pepo L. 26 landraces, belonging to four groups, were studied using 14 primers SSR, to investigate the genetic structure between accessions for different part of regions in Iran. Percentage of polymorphic loci, estimated using Nei's genetic diversity index and Shannon's information index revealed moderate or high levels of genetic variations within each landraces. Biochemical characters, including seed oil, protein, sitosterol, β-sitosterol, potassium and zinc content were evaluated among accessions. Results showed a great genetic variation for biochemical traits. Seed oil and protein content were from 26.5 to 45.8% and 21.0 to 28.6% respectively. β-Sitosterol content had a high positive correlation (r = 0.97) with oil content. It ranged from 15.1 to 26.5 mg/100 g oil. There was no significant difference for biochemical traits between naked seed pumpkin and vegetable marrow morphotypes.