Enzymatic recovery of glycopeptides from different industrial grades edible bird’s nest and its by-products:nutrient,probiotic and antioxidant activities,and physicochemical characteristics

This study was conducted to recover edible bird’s nest(EBN)hydrolysates from different grades of EBN,including the industrial by-products,using enzymatic treatment.The nutrient,physicochemical properties and antioxidant activities of the recovered hydrolysates at different hydrolysis times were evaluated.Results showed that the recovery yield of enzymatic hydrolysis was above 89%for all grades of EBN and the degree of hydrolysis increased over time.Nitrite content(0.321-0.433 mg/L)was below the permissible tolerance level for all samples.Interestingly,the antioxidant activities(DPPH and ABTS scavenging activities and ferric reducing antioxidant powder(FRAP)activity)were significantly higher(P≤0.05)in hydrolysates recovered from EBN by-products(EBNhC and EBNhD)as compared to the high grade EBN hydrolysates(EBNhA and EBNhB).The in-vitro probiotic activity of EBN and its hydrolysates were examined using the probiotic bacterium Lactobacillus plantarum.Evidently,EBN by-products hydrolysate(EBNhD)recorded the highest number of L.plantarum(1.1×1011 CFU/mL),indicating that low grade EBN has the potential as prebiotic material that promotes probiotic activity.This study demonstrated the concept of using EBN by-products hydrolysates for various applications,such as functional ingredients with enhanced bioactivities,to improve its economic value.

基于YOLOv5s的轻量化架空输电线路鸟巢检测网络

架空输电线路上的鸟巢侵占会对铁塔上的电力设备造成安全隐患,间接可能影响整个电力系统的稳定运行。针对目前架空输电线路鸟巢检测模型在复杂场景以及小目标场景下检测精度不高,检测效率低,模型复杂等问题。本研究提出一种基于YOLOv5s框架的轻量化架空输电线路鸟巢检测网络。首先在主干部分采用Fasternet重构YOLOv5s特征提取网络,降低模型复杂度,提高运行速度;然后在特征融合网络部分嵌入ConvMixer层,ConvMixer层的结构设计有助于在特征信息中更好的捕捉空间和通道的关系,提升模型对于小目标的检测能力;最后在特征融合网络部分引入ODConv模块,令送入检测头的特征图包含更多有效特征,提高模型对复杂场景和小目标的检测性能。实验结果表明,本文与基线模型YOLOv5s相比,计算量和模型体积分别减少了86%和72%,平均精度均值达到96.4%,检测速度达到104.2帧/s,验证了本文改进模型的有效性和可行性。

Small objects detection in UAV aerial images based on improved Faster R-CNN

In order to solve the problem of small objects detection in unmanned aerial vehicle(UAV)aerial images with complex background,a general detection method for multi-scale small objects based on Faster region-based convolutional neural network(Faster R-CNN)is proposed.The bird’s nest on the high-voltage tower is taken as the research object.Firstly,we use the improved convolutional neural network ResNet101 to extract object features,and then use multi-scale sliding windows to obtain the object region proposals on the convolution feature maps with different resolutions.Finally,a deconvolution operation is added to further enhance the selected feature map with higher resolution,and then it taken as a feature mapping layer of the region proposals passing to the object detection sub-network.The detection results of the bird’s nest in UAV aerial images show that the proposed method can precisely detect small objects in aerial images.

Cyathus tenuicorticalis(Agaricales,Basidiomycota),a new species from La Selva Biological Station,Costa Rica

Cyathus tenuicorticalis was found growing on decaying wood from La Selva Biological Station,Costa Rica.Specimens were analyzed using the methodology proposed for the group and specific literature for the genus.The fundamental diagnostic features for this new species are the very thin double-layered cortex in peridioles,exoperidium strongly hirsute,and a platinum bright endoperidium.Description,discussion and photographs of this new species are provided.

基于DSP的无线伺服清除鸟巢装置

针对变电站电气设备鸟巢清除需停电登高作业的问题,设计出一种基于DSP的无线伺服装置,可在电气设备带电情况下实施鸟巢清除作业。该装置可带电作业,避免了停电造成的负荷损失和非计划停运。

不同杀菌温度炖煮燕窝对小鼠体成分的调节作用

为研究不同杀菌温度对燕窝功能特性的影响,以不同杀菌温度炖煮燕窝为研究对象,将40只7周龄C57BL/6N雄性小鼠随机分为空白对照组、干燕窝组、95℃杀菌炖煮燕窝组、115℃杀菌炖煮燕窝组,口服给予小鼠炖煮燕窝匀浆90 d,通过测定小鼠的体成分、能量代谢及肠道菌群,探究炖煮燕窝对小鼠生长特性的影响。结果表明,95℃杀菌炖煮燕窝可以显著提升小鼠的瘦肉率,降低小鼠的脂肪含量;对小鼠基础代谢无显著影响,在属水平上,可以显著提高小鼠肠道菌群中毛螺菌和乳酸菌的相对丰度,降低脱硫弧菌的相对丰度;且小鼠体成分与肠道菌群具有显著相关性,小鼠瘦肉率含量与灌服95℃杀菌炖煮燕窝的小鼠肠道菌群相对丰度呈正相关,小鼠脂肪含量与灌服95℃杀菌炖煮燕窝的小鼠肠道菌群相对丰度呈负相关,95℃杀菌炖煮燕窝可以通过调节小鼠肠道菌群改变小鼠体成分含量。综上,95℃杀菌炖煮燕窝可改变小鼠体成分含量,提高肠道菌群的丰富度和多样性,有效改善小鼠肠道菌群结构,通过相关性分析发现肠道菌群的改善是调控体成分的潜在机制。

A comprehensive review of edible bird nests and swiftlet farming

Edible bird＇s nest （EBN） is currently widely consumed by the Chinese community as tonic food and functional food, which is believed to have many medicinal benefits. Some studies have reported the biochemical compositions of EBN, graded on the basis of colour, nitrate and nitrite contents. Other studies have shown significant biological effects, while ongoing research is in progress to explore potential pharmacological applications. The high demand for EBNs in the global market has forced the local regulatory bodies to monitor swiftlet farming activities, including the EBN cleaning process. Furthermore, numerous techniques have been developed to authenticate EBN; proteomics is likely to be the most promising of these methods. However, there are limited numbers of relevant protein sequences deposited at the database. More research is needed at the molecular level to explore the mechanisms behind the biological functions, such as bone strength improvement, skin rejuvenation, epidermal growth factor activity and cell proliferation.The current and future prospects of EBN and swiftlet farming are critically reviewed in this article.

Preliminary nitrite, nitrate and colour analysis of Malaysian edible bird’s nest

The high nitrite content in edible bird’s nests is a major concern to the local swiftlet industry.It lowers the price of the edible bird’s nests and it brings severe health hazards to consumers and farmers.This research investigated the nitrite and nitrate contents of eight types of local edible bird’s nests by using ion chromatography system and evaluating its colour using the CIE system in L^*a^*b^*parameters.The nitrite content obtained ranged from 5.7 lg/g for the house nests to 843.8 lg/g for the cave nests.The nitrate content for the house and cave nests was 98.2 lg/g and 36,999.4 lg/g,respectively.The cave nests with darker and redder colour had higher nitrite and nitrate contents than the brighter and more yellow house nests.This likely suggests that the nitrite and nitrate contents have correlations with edible bird’s nests colour.Correlations studies suggested that the nitrite content had high correlations with colour parameters,L^*a^*b^*of edible bird’s nests at significant level of P<0.10.These findings suggest that edible bird’s nests’colour may be a useful indicator for measuring nitrite and nitrate contaminations.

Characterization of edible bird’s nest by peptide fingerprinting with principal component analysis

OBJECTIVES:Proteins are the major component and play a key role in nutritious and therapeutic functions of edible bird’s nest(EBN);however,limited studies have been conducted on the protein due to difficulties in extraction,isolation as well as identification.This study aimed to provide comprehensive information for the quality evaluation of EBN peptides,which would be a valuable reference for further study on EBN proteins.METHODS:Here,we developed a quality control method using high performance liquid chromatography(HPLC)peptide fingerprints deriving from EBN being digested with simulated gastric fluid.The characteristic peptide peaks were collected and identified by LC-MS/MS.RESULTS:The characteristic peptide peaks,corresponding to the protein fragments of acidic mammalian chitinase-like,lysyl oxidase,and Mucin-5AC-like,were identified and quantified.Interestingly,the principal component analysis indicated that the fingerprints were able to discriminate colour of EBN(white/red)and production sites(cave/house)of White EBN on the same weight basis.As proposed by the model developed in this study,Muc-5AC-like and AMCaselike proteins were the markers with the highest discriminative power.CONCLUSIONS:The overall findings suggest that HPLC peptide fingerprints were able to clearly demonstrate peptide profile differences between genuine and adulterated EBN samples;and classify EBN samples by its color and production site.In addition,the protein identification results suggested that Muc-5AC-like protein was the major protein in EBN.

Combined enzymatic hydrolysis and herbal extracts fortification to boost in vitro antioxidant activity of edible bird's nest solution

Objective:Edible bird’s nest(EBN)is a popular traditional tonic food in Chinese population for centuries.Malaysia is one of the main EBN suppliers in the world.This study aims to explore the best strategy to boost the antioxidant potential of EBN solution.Methods:In this study,the raw EBN(4%,mass to volume ratio)was initially enzymatic hydrolyzed using papain enzyme to produce EBN hydrolysate(EBNH),then spray-dried into powdered form.Next,4%(mass to volume ratio)of EBNH powder was dissolved in ginger extract(GE),mulberry leaf extract(MLE)and cinnamon twig extract(CTE)to detect the changes of antioxidant activities,respectively.Results:Results obtained suggest that enzymatic hydrolysis significantly reduced the viscosity of 4%EBN solution from(68.12±0.69)m Pa·s to(7.84±0.31)m Pa·s.Besides,the total phenolic content(TPC),total flavonoid content(TFC),total soluble protein,DPPH scavenging activity and ferric reducing antioxidant power(FRAP)were substantially increased following EBN hydrolysis using papain enzyme.In addition,fortification with GE,MLE and CTE had further improved the TPC,TFC,DPPH scavenging activity and FRAP of the EBNH solution.Among the samples,MLE-EBNH solution showed the most superior antioxidant potential at(86.39±1.66)%of DPPH scavenging activity and(19.79±2.96)mmol/L FeSO;of FRAP.Conclusion:This study proved that combined enzymatic hydrolysis and MLE fortification is the best strategy to produce EBN product with prominent in vitro antioxidant potential.This preliminary study provides new insight into the compatibility of EBN with different herbal extracts for future health food production.

Edible Bird's Nest:Food or Medicine?

Edible bird＇s nest （EBN） is derived from the saliva of certain types of swiflets. It is consumed in many parts of the world for its nutritional and medicinal values. Although many claims have been made on the therapeutic and health- promoting effects of EBN, scientific documentations regarding these effects are very limited in published literature. It is not until recently that the biological effects of EBN are being investigated and evidence-based studies are being conducted. Several studies have found that EBN may enhance cell proliferation and differentiation and various beneficial effects have been reported in vitro as well as in vivo. While these studies point towards the potential use of EBN in the treatment or even prevention of several diseases, the mechanisms of action of EBN remain largely unknown and more explorations are needed. This review is one of the very few scientific reviews onEBN which focuses on recent evidence-based discoveries.

A sustainable way of agricultural livelihood:edible bird’s nests in Indonesia

Edible birds’nests(EBNs)have traditionally been produced in Southeast Asia.Indonesian farmers construct buildings for swiftlets and harvest their nests.EBN farming does not directly degrade forest resources and is therefore considered a sustainable means of production,whereas the expansion of other agricultural activities often relies on the degradation of natural resources.This study examines the relationship between natural resources and agricultural livelihoods,focusing on Indonesian EBN farmers.Using survey data that we collected in 2017,combined with satellite information on the extent of the forest in Central Kalimantan,Indonesia,we measured production efficiency and identified the natural and social factors that enhance production performance.The results show that a forest extent ranging between 2,000 and 6,000 meters from nesting building is positively associated with the production efficiency of EBN farming,perhaps because extensive forest could help swiftlets to collect food and build nests.Conversely,while EBN farming is a sustainable and profitable option,the initial costs of constructing buildings to house swiftlets may deter farmers from participating in the process.

Proteins:Neglected active ingredients in edible bird’s nest

Edible bird’s nest(EBN)is a kind of natural invigorant with a long history of consumption in Asia,especially in China.EBN is formed by mixing the saliva of swiftlets(Aerodramus)with feathers and other components during the breeding season.Proteins are the most important nutrient in EBN.By studying proteins in EBN,we can not only elucidate their components at the molecular level,but also study their bioactivities.Therefore,it is of great significance to study the proteins in EBN.Previous research on the proteins in EBN was preliminary and cursory,and no one has summarized and analyzed the proteins in EBN and correlated the bioactivities of these proteins with the biological functions of EBN.This article focused on the proteins in EBN,listed the proteins identified in different proteomic studies,and introduced the sources,structures and bioactivities of the most frequently identified proteins,including acidic mammalian chitinase,lysyl oxidase homolog 3,mucin-5AC,ovoinhibitor,nucleobindin-2,calciumbinding protein(MW:4.5×10~4)and glucose-regulated protein(MW:7.8×10~4).The properties of these proteins are closely related to the bioactivities of EBN.Therefore,this article can provide inspiration for further research on the efficacy of EBN.

NE TIGER Premieres New Hua Fu At Bird’s Nest

On the evening of September 25, China’s leading luxury fashion brand NE TIGER presented its premiere fashion show of Hua Fu(Chinese national dress) at a concert of superstars from China, Japan and South Korea,

体视镜在燕窝鉴别中的应用

目的:研究体视镜在燕窝鉴别中的可行性。方法:观察白燕碎、血燕盏、银耳碎及涂胶白燕盏在体视镜下的特征区别。结果:体视镜可区分燕窝碎与伪品银耳,主要区别在于两者的透明度及表面纹理:体视镜还可根据燕窝的表面纹理及绒羽的存在状态识别出涂胶燕窝。讨论:体视镜可用于燕窝的鉴别,尤适于在研究初期对大量商品作普查时使用。

燕窝对正常小鼠肠道菌群的影响

观察燕窝对正常小鼠肠道菌群的影响,评价其对肠道微生态调节的作用。昆明种小鼠40只,分成4组,即正常对照组,燕窝高、中、低剂量组。灌胃给药28d后,选用厌氧及需氧菌选择性培养基测定盲肠内容物标本中代表性菌种肠杆菌、肠球菌、产气荚膜梭菌、拟杆菌、双歧杆菌和乳酸杆菌数量。与空白对照组相比,燕窝各剂量组小鼠肠道肠杆菌含量显著降低(P<0.01或P<0.05);燕窝高剂量组产气荚膜梭菌含量显著下降(P<0.05);燕窝中、高剂量组肠球菌含量显著下降(P<0.05或P<0.01);燕窝中、高剂量组小鼠拟杆菌含量显著增加(P<0.05);燕窝高剂量组双歧杆菌、乳酸杆菌含量显著上升(P<0.05)。说明燕窝可通过扶植肠道有益菌、抑制有害菌来调节小鼠肠道菌群。

燕窝中唾液酸的含量测定

目的:建立燕窝中N-乙酰神经氨酸的分离分析方法。方法:燕窝中的N-乙酰神经氨酸在0.5mol·L^(-1)硫酸氢钠溶液中水解30min后,以邻苯二氨盐酸盐(10mg·mL^(-1))为衍生化试剂,80℃水浴中衍生40min。采用Alltima C_(18)柱(250mm×4.6mm,5μm);流动相为1.0%四氢呋喃水溶液(含0.2%磷酸)-乙腈(92:8);流速为1.0mL·min^(-1);柱温:35℃;紫外检测波长230nm。结果:N-乙酰神经氨酸在40～320μg·mL^(-1)范围内线性良好;平均回收率分别为96.82%;RSD为1.2%(n =6)。结论:本方法具有灵敏度高、重复性好等特点,可准确测定燕窝中N-乙酰神经氨酸的含量,同时也为真假燕窝的鉴别提供了一种行之有效的方法。

响应曲面法优化燕窝糖蛋白提取工艺研究

通过水浸提法提取燕窝糖蛋白,以蛋白质提取率及多糖提取率为考察指标,研究浸提时间、料液比、浸提次数对燕窝糖蛋白提取效果的影响,并利用响应曲面法对燕窝糖蛋白提取工艺进行优化。结果表明:燕窝糖蛋白提取的最佳工艺条件为:浸提时间为2.6 h,料液比为1:47,浸提次数为2次,得到的蛋白质提取率为3.96%,多糖提取率为1.54%,提取液经浓缩沉淀,透析冻干后得到糖蛋白粗品,其得率为3.01%。另外,通过此法制备的糖蛋白粗品中蛋白质含量和多糖含量分别为59.06%和19.2%。

燕窝糖蛋白纯化及多克隆抗体的制备

燕窝经60℃水浴提取、醇析,得糖蛋白粗品,再经DEAE-Sepharose Fast Flow离子交换层析、SephacrylS-200凝胶过滤层析分离纯化得到了成分均一的燕窝特征组分—燕窝糖蛋白,经SDS-PAGE凝胶电泳测定其分子量约为60k Da;通过β消去反应,表明燕窝糖蛋白中存在O型糖肽键。经一定程序免疫新西兰大白兔,获得了兔抗燕窝糖蛋白抗血清,采用Protein A-Sepharose 4B亲和层析纯化,获得抗燕窝糖蛋白抗体。本实验为进一步利用抗原抗体特异性识别的性质,建立燕窝特征糖蛋白组分的酶联免疫检测方法及燕窝的鉴伪奠定了基础。