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.

Insights on the molecular mechanism of neuroprotection exerted by edible bird’s nest and its bioactive constituents

Neurodegenerative diseases are often associated with the accumulation of oxidative stress and neuroinflammation.Edible bird’s nest(EBN)is a glycoprotein(sialylated mucin glycopeptides)found to be beneficial against neurodegenerative diseases.Antioxidative,anti-inflammatory,and anti-apoptotic properties of EBN in preserving neuronal cells were widely researched using in vitro and in vivo models.Functional effects of EBN are often linked to its great number of antioxidants and anti-inflammatory glycopeptides.Bioactive compounds in EBN,especially sialic acid,add value to neurotrophic potential of EBN and contribute to neuronal repair and protection.Various studies reporting the neuroprotective effects of EBN,their molecular mechanisms,and neuroactive composition were gathered in this review to provide better insights on the neuroprotective effects of EBN.

Plant Composition of Skuas Nests at Hennequin Point, King George Island, Antarctica

We investigate the plant composition in the Skuas nest at Hennequin Point, located in the Admiralty Bay Area, King George Island, Antarctica. Sample of 61 activity nests were analyzed. 21 plant and lichenized fungi species were found in the nest composition, being the mosses Sanioniauncinata (Hedw.) Loeske and Polytrichastrumalpinum (Hedw) G. S. Smith the most frequent species found in the Skuas nests. Usneaantarctica Du Rietz was the most frequent lichen and the grass Deschampsiaantarctica Desv was the most frequent flowering plant found in the nests. These results contribute for the environmental menagement of the Admiralty Bay area research activities.

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.

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.

Effects of Sialic Acid from Edible Bird Nest on Cell Viability Associated with Brain Cognitive Performance in Mice

Background:Edible bird nest(EBN)is a natural food product rich in glycoprotein such as sialic acid,which has been reported to improve brain functions.The EBN is widely consumed due to its higher nutritional contents and antioxidant status;however,an interaction of EBN on brain cell metabolic activity and viability are still unclear.Objective:The objectives of this study were to identify the effect of sialic acid from EBN on the cell viability and to determine the appropriate concentration of sialic acid on cognitive performance in mice.Materials and Methods:The viability of pheochromocytoma and neuroblastoma cell lines were tested using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay.For in vivo study,7-week-old female BALB/c mice were randomly assigned into four treatment groups and were treated with sialic acid for 21 days.At day 22,all mice were tested on cognitive performance by Y-maze test.Results:Treatment concentration of sialic acid extract and sialic acid standard at 60μg/mL(0.6 ppm)increased cell viability and showed no cytotoxicity effects in pheochromocytoma and neuroblastoma cell lines.In addition,an administration of higher dose of sialic acid at 0.6 ppm in animals improved Y-maze test performance,which they showed significantly higher number of entries and time spent in the novel arm.Conclusion:Thus,the current study shows that the sialic acid extract at 0.6 ppm improved brain cognitive performance in mice associated with an increased viability of pheochromocytoma and neuroblastoma cell lines.

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.