Effect of different drying methods on the amino acids,α-dicarbonyls and volatile compounds of rape bee pollen

The significant demand for high quality food has motivated us to adopt appropriate processing methods to improve the food nutritional quality and flavors.In this study,the effects of five drying methods,namely,pulsed vacuum drying(PVD),freeze drying(FD),infrared drying(IRD),hot-air drying(HAD)and sun drying(SD)on free amino acids(FAAs),α-dicarbonyl compounds(α-DCs)and volatile compounds(VOCs)in rape bee pollen(RBP)were determined.The results showed that FD significantly released the essential amino acids(EAAs)compared with fresh samples while SD caused the highest loss.Glucosone was the dominantα-DCs in RBP and the highest loss was observed after PVD.Aldehydes were the dominant volatiles of RBP and SD samples contained more new volatile substances(especially aldehydes)than the other four drying methods.Comprehensively,FD and PVD would be potential methods to effectively reduce the quality deterioration of RBP in the drying process.

Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens

The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods.

Allergen degradation of bee pollen by lactic acid bacteria fermentation and its alleviatory effects on allergic reactions in BALB/c mice

Food allergy as a global health problem threatens food industry.Bee pollen(BP)is a typical food with allergenic potentials,although it performs various nutritional/pharmacological functions to humans.In this study,lactic acid bacteria(LAB)were used to ferment Brassica napus BP for alleviating its allergenicity.Four novel allergens(glutaredoxin,oleosin-B2,catalase and lipase)were identified with significant decreases in LAB-fermented BP(FBP)than natural BP by proteomics.Meanwhile,metabolomics analysis showed significant increases of 28 characteristic oligopeptides and amino acids in FBP versus BP,indicating the degradation of LAB on allergens.Moreover,FBP showed alleviatory effects in BALB/c mice,which relieved pathological symptoms and lowered production of allergic mediators.Microbial high-throughput sequencing analysis showed that FBP could regulate gut microbiota and metabolism to strengthen immunity,which were closely correlated with the alleviation of allergic reactivity.These findings could contribute to the development and utilization of hypoallergenic BP products.

Effect of fermented bee pollen on metabolic syndrome in high-fat diet-induced mice

Bee pollen has potential in preventing metabolic syndrome(MetS).The present study aimed to investigate the effect of yeast-fermented wall-broken bee pollen(YB)intervention on ICR mice with MetS induced with a high-fat(HF)diet.After YB intervention in mice for 16 weeks,the effect on alleviating MetS was evaluated based on MetS serum parameters,hepatic oxidant status markers and gut microbial populations.The results of animal experiment showed that YB intervention attenuated MetS.Based on multivariate statistical analysis results,YB treatment signifi cantly increased glutathione S-transferase(GST)and catalase(CAT)activities and decreased the malondialdehyde(MDA)level in the liver.Further investigation showed that YB restored the Nrf-2-Keap-1 pathway to alleviate oxidative stress.Additionally,gut microbial community analysis revealed that YB restored the increase in the Firmicutes to Bacteroidetes(F/B)ratio(6.94 for the HF group and 3.74 for HF+YB group)and improved Lactobacillus and Lactococcus abundance induced by the HF diet.Overall,YB improved function and prevented MetS by modulating the gut microbiota and alleviating oxidative stress.

Effect of Bee Pollen on Reproductive Performance of Broiler Breeders

[Objective]The paper was to verify whether chestnut bee pollen can be used as feed for breeding chickens and its appropriate addition proportion.[Method]A total of 92444-week-old Ross 308 broiler breeders of parent generation with a male to female ratio of 1∶10 were randomly divided into 4 groups,with 3 replicates in each group and 7 cocks and 70 hens in each replicate.The broiler breeders in the control group were fed with the basal diet,and those in experimental groups were fed with the diets supplemented with 0.5%,1.0%and 1.5%chestnut bee pollen.The feeding trial lasted 35 d.[Result]Addition of chestnut bee pollen at different proportions improved the laying rate of breeder hens in different degrees.The experimental group supplemented with 1.5%chestnut bee pollen increased the laying rate by 9.1%,reduced the rate of unqualified eggs(broken eggs,cracked eggs,thin shelled eggs and hard shelled eggs)by 71.4%,increased the fertilization rate of hatching eggs and healthy chick rate by 4.4%and 5.2%,and improved the concentrations of testosterone(T),follicle stimulating hormone(FSH)and luteinizing hormone(LH)in breeder cocks by 60.8%,32.3%and 61.4%,respectively.Statistical analysis showed that the results were significantly different.[Conclusion]Addition of chestnut bee pollen at certain concentration can improve the reproductive performance of breeder cocks and breeder hens,and improve the body immunity.

Bee pollen extract of Malaysian stingless bee enhances the effect of cisplatin on breast cancer cell lines

Objective: To evaluate the antioxidant and antiproliferative effect of methanolic bee pollen extract(BPE) of Malaysian stingless bee [Lepidotrigona terminata(L. terminata)]and its synergistic effect with cisplatin(a chemotherapeutic drug) on MCF-7 cancer cell line.Methods: The antioxidant activity of BPE from L. terminata was measured by using1,1-diphenyl-2-picrylhydrazyl radical(DPPH) assay. Antiproliferative activity at different concentrations of BPE and cisplatin was determined through using MTT assay on MCF-7 and L929 cell lines. An interaction effect(synergistic, additive and antagonistic) between BPE and cisplatin was determined by Compu Syn software based on MTT assay data.Results: The EC50(50% decrement of DPPH inhibition) of BPE was 0.5 mg/m L.L. terminata BPE exhibited antiproliferative activity on both cancer and normal cell lines.The IC50(concentration of drug that was required for 50% of cell inhibition in vitro) of BPE on MCF-7 was 15 mg/m L whereas in normal cell line L929 was 26 mg/m L. The IC50 for cisplatin on MCF-7 was 20 mmol/L. The combination effect of BPE and cisplatin on MCF-7 cells showed that BPE at 15 mg/m L was able to potentiate the inhibitory effect of cisplatin at all different concentrations(2.5–20.0 mg/m L). The average of cancer cells inhibition which was potentiated by BPE was around 50%. A combination index values of less than 1 reported in the Compu Syn software further proved the synergistic effect between BPE and cisplatin, suggesting that BPE was working synergistically with cisplatin.Conclusions: Our study therefore suggested that BPE of Malaysian stingless bee,L. terminata is a potential chemopreventive agent and can be used as a supplementary treatment for chemotherapy drugs. BPE might be able to be used to potentiate the effect of chemotherapy drugs with the possibility to reduce the required dose of the drugs. The molecular mechanisms of how the BPE exerts antiproliferative activity will be a much interesting area to look for in future studies.

Investigation of the nutraceutical potential of monofloral Indian mustard bee pollen

OBJECTIVE： This study was designed to investigate the nutraceutical potential of monofloral Indian mustard bee pollen （MIMBP）. METHODS： The nutritional value of MIMBP was examined in terms of proteins, fats, carbohydrates, and energy value. Its chemical composition in terms of total polyphenol and flavonoid content was determined. MIMBP was screened for free flavonoid aglycones by developing and validating a high-performance liquid chromatography-photo diode array （HPLC-PDA） method. MIMBP was analyzed for in vitro antioxidant effect in terms of 2,2-diphenyl-l-picrylhydrazyl （DPPH） radical-scavenging activity. RESULTS： MIMBP was found to be comprised of proteins （（182.2±5.9） g/kg）, fats （（137.7±6.8） g/kg） and carbohydrates （（560.6±17.4） g/kg）, which result in its high energy value （（17 616.7±78.6） kJ/kg）. MIMBP was found to contain polyphenols （（18 286.1±374.0） mg gallic acid equivalent/kg） and flavonoids （（1 223.5±53.1） mg quercetin equivalent/kg）. The HPLC-PDA analysis revealed the presence of kaempferol （（65.4±0.5） mg/kg） and quercefin （（51.4±0.4） mg/kg） in MIMBP, which can be used as markers for determining the quality of bee pollen. The MIMBP extract showed DPPH free radical-scavenging activity with a half maximal inhibitory concentration of 54.79 μg/mL. CONCLUSION： The MIMBP was found to be a rich source of nutrients providing high caloric value, which makes it a candidate for a potential nutraceutical agent. The study also illustrated the high antioxidant content of MIMBP, especially in the principle polyphenols and flavonoids, which suggests its potential role in the prevention of free radical-implicated diseases. The DPPH-scavenging effect of MIMBP further confirmed its antioxidant potential. Additionally, we developed a simple, specific and accurate HPLC-PDA method for the identification and quantification of free flavonoid aglycones. This can be applied in future screenings of the quality of pollen collected by honeybees.

Waste-to-wealth:Functional biomass carbon dots based on bee pollen waste and application

Waste utilization is not only the protection of the environment and the practice of green chemistry,but also one of the ways to develop new materials.Herein,we report two biomass carbon dots which prepared from bee pollen waste by one-step hydrothermal method.The new two carbon dots were used in sensing,cell imaging and plant growth regulation.The differences in the structure and properties of the two carbon dots were evaluated by TEM,XPS,TG and various spectroscopic methods.Both two carbon dots contain abundant functional groups,polyatomic doping,excellent water solubility and stable photoluminescence.Due to these good properties,we have demonstrated its versatile applications in Fe3+sensing,cell imaging and plant growth regulation.It shows sensitive and specific Fe^(3+) responsiveness and good biocompatibility.This research provides a green and simple method for the recycling and reuse of bee pollen waste,and also provides a reference for the application of biomass carbon dots.

Flavonoids from rape bee pollen on the clinical effects of antioxidant activity

Background Flavonoids from fruits, vegetables and plants have been widely studied on their improving lipidemia, anti-inflammation, anti-platelet aggregation and anti-oxidative activities. However, t know if flavonoids from rape bee pollen have the same effects in patients with dyslipidemia （DL）, effects of we don＇ type 2 diabetes mellitus（T2DM）, and cerebral infarction（CI）. Methods The study involved with patients selected and divided into 4 groups, 30 cases of DL, of T2DM, of CI and health control （HC） for each. Forty mg flavonoids from rape bee pollen administrated orally twice a day for two months. Blood sugar （BG）, total cholesterol （TC）, triglyceride （TG）, high density lipoprotein-cholesterol （HDL-C）, low white blood-cell counts （WBC）, platelet counts （PLT）, high-sens malondialdehyde （MDA） were analyzed in four groups before and after density lipoprotein-cholesterol （LDL-C）, itivity C-reactive protein （hsCRP） and taking flavonoids for two months. Results （1） Basic levels of TC, BG, WBC, PLT and hsCRP in groups of T2DM, CI, and TG and MDA in groups of DL, PLT, T2DM and CI were significantly higher than those in HC （P 〈 0.05-0.001）. （2） The levels of hsCRP and MDA were significantly decreased, flavonoids for two months （P 〈 0.05-0.001） in group of while HDL-C was remarkably increased DL, T2MD, and CL These indexes were not the group of HC after taking flavonoids （P 〉 0.05）. Conclusions The results could indieat disturbance, inflammation, and high oxidative stress in patients with dyslipidemisa, type 2 diabet TG, WBC, after taking different in e metabolic es mellitus, and cerebral infarction. The flavonoids from rape bee pollen may have effects of antioxidant activity, improving lipids, and anti-inflammation on these patients.

3种功能食品原料提取物毒性研究及安全性评价

目的 研究3种功能食品原料(红景天、五味子和蜂花粉)醇/醇水提取物毒性并评价其安全性。方法 利用小鼠急性毒性实验、遗传毒性实验(小鼠骨髓细胞微核实验、雄性小鼠精子畸形实验)和大鼠30 d喂养实验对3种提取物的毒性进行考察。结果 小鼠对红景天、五味子和蜂花粉提取物的最大耐受量都大于20 g/(kg·bw);3种提取物在遗传毒性实验均呈阴性反应;给予大鼠5.0 g/(kg·bw)红景天、五味子、蜂花粉提取物(分别相当于成人日推荐量250倍、250倍、500倍)连续灌胃30d,大鼠生长正常,无中毒症状、异常症状和死亡,各试食组动物体重、进食量、饲料利用率、血常规指标、常见血液生化指标、脏器重量以及病理组织学等指标与阴性对照组比较,无毒性反应。结论 红景天、五味子、蜂花粉提取物属无毒物质,无遗传毒性和长期毒性。本研究为以红景天、五味子和蜂花粉提取物为原料的功能食品开发和应用提供了一定的安全性依据。

荞麦蜂花粉多酚对α-淀粉酶的抑制作用

蜂花粉多酚是一类能够有效降低血糖的天然物质。α-淀粉酶是高等生物体内血糖控制的关键酶,抑制其活性有助于控制餐后血糖。为探究蜂花粉多酚抑制α-淀粉酶发挥降糖活性的机制,本文以荞麦蜂花粉多酚(buckwheat bee pollen polyphenol,BBPP)为对象,采用比色法、荧光分光光度法研究BBPP对α-淀粉酶活性影响及其抑制机理。结果表明,BBPP能对α-淀粉酶产生较强的抑制作用,半抑制浓度(IC_(50))为2.00±0.06 mg/mL,抑制类型为可逆性混合型抑制。高温、强碱、光照以及高浓度氧化剂与还原剂等处理,均能降低BBPP对α-淀粉酶的抑制作用。在273~298 K和298~310 K时其结合过程分别为动态猝灭和静态猝灭。随着BBPP浓度增加,α-淀粉酶荧光最大发射波长产生蓝移,表明α-淀粉酶构象改变,疏水性增加。本研究发现荞麦蜂花粉多酚对α-淀粉酶具有较强抑制作用,对荞麦蜂花粉多酚的临床开发利用具有重要的理论参考价值。

The difference in pollen harvest between Apis mellifera and Apis cerana in a Tibetan alpine meadow

To explore the difference in pollen harvest between the western honey bee Apis mellifera and a native eastern honey bee A.cerana in the Zoige alpine meadows in the northeastern part of the QinghaiTibetan Plateau,we investigated species diversity of the harvested pollen and the amount of harvested pollen per bee for both species,and calculated the niche overlap(in terms of similarity in harvested pollen)between the two bee species during the flowering season from June to August 2016.Results showed that the species diversity of the harvested pollen was indistinguishable between the two bee species.Nevertheless,A.mellifera carried more(although not significant)pollens per bee than A.cerana.Moreover,pollen composition differed between the two bee species:A.mellifera mainly foraged on Anemone rivularis,Saussurea nigrescens and Anemone trullifolia,while A.cerana foraged on Anemone rivularis,Stellera chamaejasme,and Pedicularis longiflora.Consistently,the niche overlap between the two honeybee species was particularly small in several observations.Our results indicate a niche separation in pollen resource between the two honeybee species in a Tibetan alpine meadow.

未破壁蜂花粉对绵羊生长性能、免疫力和经济效益的影响

试验旨在研究未破壁蜂花粉对绵羊生长性能、免疫力和经济效益的影响。试验选取体重(36.53±3.81) kg的湖羊母羊30只,随机分成5组,每组3个重复,每个重复2只羊。对照组(CK组)羊饲喂基础日粮,各试验组羊分别饲喂添加2 (A组)、5 (B组)、8 (C组)、11 g/(只·d)(D组)的未破壁蜂花粉的基础日粮。试验期40 d,其中预试期10 d,正式试验期30 d。结果显示,与CK组对比,B组湖羊平均日采食量极显著降低(P<0.01)。与CK组相比,A组湖羊血清免疫球蛋白A (IgA)含量显著上升(P<0.05),免疫球蛋白G(IgG)含量极显著上升(P<0.01);B组和C组血清IgG含量显著上升(P<0.05)。与CK组对比,A组、B组、C组和D组饲料总成本分别增加-1.29%、3.99%、17.83、31.66%,增重收益分别增加33.33%、6.67%、-6.67%和-11.79%,经济效益分别增加124.61%、13.72%、-71.23%、-126.33%。研究表明,绵羊适当饲喂未破壁蜂花粉可降低饲料投入,提升绵羊生长性能、血清免疫功能和经济效益,建议在湖羊生产添加2 g/(只·d)未破壁蜂花粉。

蜂花粉中新烟碱农药的残留分析及膳食摄入风险评估

该研究探讨了我国不同植物源66个蜂花粉样品中8种新烟碱农药的残留情况,并根据残留结果进行普通人群膳食摄入风险评估。结果发现,样品检出率为50.0%,共检出5种新烟碱农药,包括啶虫脒、吡虫啉、噻虫嗪、噻虫胺和呋虫胺,检出率最高的为噻虫嗪(31.8%),残留浓度最高为啶虫脒(195.1 ng/g)。4种植物源的蜂花粉中新烟碱农药的残留存在显著差异:茶花粉的检出率显著高于其他3种花粉;杂花粉的残留浓度显著高于茶花粉和油菜花粉,残留浓度从高到低依次为杂花粉、荞麦粉、茶花粉、油菜花粉。来自6个主要地区的蜂花粉残留情况也有所不同,这可能跟我国不同地区和不同作物中新烟碱农药的施用情况相关。依据新烟碱农药的残留浓度进行人类膳食摄入风险评估,评估结果(风险商值均小于1%)说明蜂花粉中的新烟碱农药残留风险可接受。

蜂花粉和蜂蜜的添加及焙烤条件对曲奇品质及功能特性的影响

通过单因素和正交试验,研究蜂花粉添加量、蜂蜜添加量、焙烤温度和焙烤时间对曲奇的色泽(明亮度L*)、硬度和感官品质的影响,确定曲奇的最佳制备工艺,并通过聚类分析确定曲奇硬度等级。结果表明,曲奇的最佳制备工艺为蜂花粉添加量20%(以小麦粉干基计),蜂蜜添加量10%,焙烤温度170℃,焙烤时间18 min,1级曲奇硬度为360 g~420 g。DPPH自由基和羟基自由基清除能力及总还原能力测试结果表明,同时添加蜂花粉和蜂蜜能显著提高曲奇的抗氧化能力。

油菜蜂花粉的生物活性及其开发利用现状

人们健康理念日益增强,油菜蜂花粉作为一种天然保健原料,研究开发价值极高。文章介绍了油菜蜂花粉富含的多种营养成分和活性物质,主要总结油菜蜂花粉在抗氧化、抗炎、增强免疫、抗菌、保护前列腺、抗糖尿病并发症、抗肿瘤、调节保护肠道、保护卵巢等方面的生物活性和药理作用,以及油菜蜂花粉在蜂产品、保健品、食品、医药、化妆品中的应用,并对油菜蜂花粉的发展方向进行了展望。

蜜生假丝酵母LGL-2发酵油菜蜂花粉酵素工艺优化及品质评价

以油菜蜂花粉为主要原料,以蜂蜜中选育出的蜜生假丝酵母LGL-2为试验菌株,研究不同发酵时间、发酵温度、接种量和底物含量对油菜蜂花粉酵素总酚含量的影响。以总酚含量为指标,采用响应面法优化油菜蜂花粉酵素发酵工艺条件。在此条件下,进一步比较分析油菜蜂花粉及其酵素的酚类化合物、挥发性风味成分和抗氧化活性。结果表明:油菜蜂花粉酵素的最佳发酵工艺参数为发酵时间48 h、发酵温度30℃、接种量20%、底物含量30%,此时油菜蜂花粉酵素总酚含量可达11.48 mg GAE/g。采用高效液相色谱(HPLC)分析酚类化合物,发现其内包含没食子酸、对香豆酸、芦丁、鞣花酸和槲皮素,各酚类化合物含量经蜜生假丝酵母LGL-2发酵后均有所提高。采用相对气味活度值法(ROAV)结合顶空固相微萃取-气相色谱-质谱技术(HS-SPME-GC-MS)对油菜蜂花粉及其酵素的挥发性香气成分进行测定分析,共检测出26种挥发性香气成分,其中7种被鉴定为油菜蜂花粉酵素关键性挥发性香气成分,部分醇类和酯类物质含量提升为产品带来优良风味。抗氧化活性试验表明,相比于发酵前,油菜蜂花粉酵素具有更强的DPPH自由基清除能力(DPPH·)、ABTS^(+)自由基清除能力(ABTS^(+)·)以及铁离子还原能力(FRAP)。综上,经蜜生假丝酵母LGL-2发酵能有效提高油菜蜂花粉的酚类物质含量、风味品质及抗氧化活性。