A comprehensive review of edible bird's nest

Comprehensive site- and structure-specific profiling of N-glycosylation of edible bird's nest (EBN) proteome using label-free quantitative glycoproteomics

Glycoproteins, which are involved in numerous biological functions, are among the most critical functional ingredients in an edible bird's nest (EBN). To gain a comprehensive understanding of the glycoprotein species within EBN, a label-free, site-specific glycoproteomic approach was used to analyze their N-glycoproteins, N-glycopeptides, and N-glycans systematically. A total of 127 N-glycoproteins were identified in EBN, of which 72 were found in house-EBN and 63 in cave-EBN, yielding 4195 and 5649 glycopeptides, respectively. Eight N-glycoproteins were common to both types, comprising 288 intact N-glycopeptides and 235 N-glycans. The results showed a relatively high abundance of terminally sialylated and core fucosylated N-glycans in EBN. Moreover, through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, it was observed that EBN N-glycoproteins predominantly participated in neurodegeneration-multiple illness, cell adhesion molecules, TNF signaling, and TGF-beta signaling pathways. These findings provide insights into EBN glycoprotein site-specific N-glycosylation and its biological roles and processes.

Role and Mechanism of Sialic Acid in Alleviating Acute Lung Injury through In Vivo and In Vitro Models

Excessive inflammatory reactions are the most important pathological injury factor in acute lung injury (ALI). Our recent study found that sialic acid had an anti-colitis effect. In this study, the effect of sialic acid (SA) on acute lung inflammation was investigated. A lipopolysaccharide (LPS)-induced ALI animal model and LPS-stimulated HUVEC cell model were used to evaluate the anti-inflammatory effect of SA and study its molecular mechanisms. Compared with the LPS group, the lung index of the SA group decreased from 0.79 ± 0.05% to 0.58 ± 0.06% (LPS + 50 SA) and 0.62 ± 0.02% (LPS + 100 SA), with p < 0.01, suggesting that SA could improve the pulmonary edema of mice and alleviate LPS-induced lung injury. Transcriptome research identified 26 upregulated genes and 25 downregulated genes involved in the protection of SA against ALI. These genes are mainly related to the MAPK and NF-κB signaling pathways. Our study also proved that SA markedly downregulated the expression of inflammatory factors and blocked the JNK/p38/PPAR-γ/NF-κB pathway. Meanwhile, SA treatment also upregulated the expression of HO-1 and NQO1 in ALI mice. In vitro, SA obviously repressed the expressions of inflammatory cytokines and the JNK/p38-NF-κB/AP-1 pathway. SA also regulated the expression of oxidative stress-related genes through the Nrf2 pathway. Taken together, SA exhibits a protective role by modulating the anti-inflammatory and anti-oxidation pathways in ALI, and it may be a promising candidate for functional foods to prevent ALI.

Identification of the Wound Healing Activity Peptidome of Edible Bird's Nest Protein Hydrolysate and the In Silico Evaluation of Its Transport and Absorption Potential in Skin

In this study, edible bird's nest (EBN) was proven to be a suitable source of bioactive peptides via enzymatic hydrolysis. The ultrafiltration component of the EBN peptides (EBNPs, Mw < 3 000 Da) could be responsible for moderate moisture retention and filaggrin synthesis. It was found that EBNP had a great capacity to protect HaCaT keratinocytes from DNA damage caused by UVB-irradiation and enhance wound healing by increasing the migratory and proliferative potential of cells. Furthermore, the external application of EBNP could effectively repair high glycolic acid concentration-induced skin burns in mice. A total of 1 188 peptides, predominantly the hydrophobic amino acids (e.g., Leu, Val, Tyr, Phe), were identified in the EBNP by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Molecular docking showed that hydrophobic tripeptides from EBNP had a good binding affinity to proton-dependent oligopeptide transporter PepT1. Our data indicated that the hydrophobic amino acid-rich EBNP plays an important role in skin wound healing.

Effects of house-cultivated edible bird's nest on immunoglobulin and cytokine release in vitro

Background and Aim

Edible bird's nest (EBN) is known as the "Caviar of the East" because of its high nutritional and medicinal values. Nevertheless, its effect on human immunity is yet to be explored. This study examined the effects of EBN's aqueous extract (EBNE) on human immunity through the modular immune in vitro construct (MIMIC) model consisting of peripheral tissue equivalent (PTE) and lymphoid tissue equivalent (LTE) modules.

Materials and Methods

One hundred twenty mL of full blood was obtained from four healthy human volunteers. The human immune system was simulated using an in vitro model, called MIMIC. Under EBNE treatment, monocyte transendothelial migration through reversed endothelial layers was observed. Using PTE and LTE modules, monocytes were differentiated into dendritic cells with lipopolysaccharide, then co-cultured with T- and B-cells for cytokine and immunoglobulin (Ig) production. The human cytokine array G2000 and quantitative human Ig isotyping array were used to identify the cytokine profile and Ig isotypes, respectively.

Results

IgE, IgA, and IgG3 levels were significantly raised by EBNE. These cytokines, including brain-derived neurotrophic factor, ciliary neurotrophic factor, glial cell line-derivative neurotrophic factor, insulin-like growth factor 1, and insulin-like growth factor binding protein 4, were generated.

Conclusion

For the first time, this work uses a MIMIC model to illustrate the impact of EBNE on human immune response. This new understanding of EBN's immunoregulatory effect allows for further exploration of how EBN interacts with the human immune system.

Interaction of prenatal maternal selenium and manganese levels on child neurodevelopmental trajectories-the Shanghai birth cohort study

OBJECTIVE

The fetal brain is particularly plastic, and may be concurrently affected by chemical exposure and malnutritional factors. Selenium is essential for the developing brain, and excess manganese exposure may exert neurotoxic effects. However, few epidemiological studies have evaluated the interaction of manganese and selenium assessed in different prenatal stages on postnatal neurodevelopmental trajectories.

METHODS

This study contained 1024 mother-child pairs in the Shanghai-birth-cohort study from 2013 to 2016 recruited since early/before pregnancy with complete data on manganese and selenium levels in different prenatal stages and infant neurodevelopmental trajectories. Whole blood manganese and selenium in early pregnancy and around birth were measured by inductively-coupled-plasma-mass-spectrometry (ICP-MS), children's cognitive development was evaluated at 6, 12, and 24 months of age using Age & Stage-Questionnaire (ASQ)-3 and Bayley-III. Multiple linear regression was used to investigate the interaction of prenatal selenium and manganese on neurodevelopmental trajectories.

RESULTS

The prenatal manganese and selenium levels were 1.82 ± 0.98 μg/dL and 13.53 ± 2.70 μg/dL for maternal blood in early pregnancy, and 5.06 ± 1.67 μg/dL and 11.81 ± 3.35 μg/dL for umbilical cord blood, respectively. Higher prenatal Se levels were associated with better neurocognitive performances or the consistently-high-level trajectory (P < 0.05), with more significant associations observed in early pregnancy than around birth. However, such positive relationships became non-significant or even adverse in high (vs. low) manganese status, and the effect differences between low and high manganese were more significant in early pregnancy.

CONCLUSIONS

Prenatal Selenium was positively associated with child neurodevelopment, but prenatal high manganese may mitigate such favorable effects. The effects were mainly observed in earlier prenatal stage.

Revealing Edible Bird Nest as Novel Functional Foods in Combating Metabolic Syndrome: Comprehensive In Silico, In Vitro, and In Vivo Studies

Metabolic dysfunction, which includes intra-abdominal adiposity, glucose intolerance, insulin resistance, dyslipidemia, and hypertension, manifests into metabolic syndrome and related diseases. Therefore, the discovery of new therapies in the fight against metabolic syndrome is very challenging. This study aims to reveal the existence of an edible bird nest (EBN) as a functional food candidate that may be a new alternative in fighting metabolic syndrome. The study included three approaches: in silico molecular docking simulation, in vitro, and in vivo in rats fed on cholesterol- and fat-enriched diets. Four terpenoids of Bakuchiol, Curculigosaponin A, Dehydrolindestrenolide, and 1-methyl-3-(1-methyl-ethyl)-benzene in EBN have been identified through LCMS/MS-QTOF. In molecular docking simulations, Bakuchiol and Dehydrolindestrenolide are considered very potent because they have higher inhibitory power on the four receptors (iNOS, ROS1 kinase, FTO, and lipase) than standard drugs. In vitro tests also provide insight into the antioxidant, antidiabetic, and antiobesity activities of EBN, which is quite feasible due to the smaller EC50 value of EBN compared to standard drugs. Interestingly, in vivo studies also showed significant improvements (p < 0.05) in the lipid profile, blood glucose, enzymatic levels, and inflammatory biomarkers in rats given high-dose dietary supplementation of EBN. More interestingly, high-dose dietary supplementation of EBN upregulates PGC-1α and downregulates HMG-CoA reductase. Comprehensively, it has been revealed that EBN can be novel functional foods for combating metabolic syndrome.

Enzyme-Digested Edible Bird’s Nest (EBND) Prevents UV and arid Environment-Induced Cellular Oxidative Stress, Cell Death and DNA Damage in Human Skin Keratinocytes and Three-Dimensional Epithelium Equivalents

The aim of this study is to investigate the repressive effects of enzyme-digested edible bird’s nest (EBND) on the combination of arid environment and UV-induced intracellular oxidative stress, cell death, DNA double-strand breaks (DSBs) and inflammatory responses in human HaCaT keratinocytes and three-dimensional (3D) epithelium equivalents. An oxygen radical antioxidant capacity assay showed that EBND exhibited excellent peroxyl radical scavenging activity and significantly increased cellular antioxidant capacity in HaCaT cells. When EBND was administered to HaCaT cells and 3D epitheliums, it exhibited significant preventive effects on air-drying and UVA (Dry-UVA)-induced cell death and apoptosis. Dry-UVA markedly induced intracellular reactive oxygen species (ROS) generation in HaCaT cells and 3D epitheliums as quantified by CellROX® Green/Orange reagents. Once HaCaT cells and 3D epitheliums were pretreated with EBND, Dry-UVA-induced intracellular ROS were significantly reduced. The results from anti-γ-H2A.X antibody-based immunostaining showed that EBND significantly inhibited Dry-UVA-induced DSBs in HaCaT keratinocytes. Compared with sialic acid, EBND showed significantly better protection for both keratinocytes and 3D epitheliums against Dry-UVA-induced injuries. ELISA showed that EBND significantly suppressed UVB-induced IL-6 and TNF-α secretion. In conclusion, EBND could decrease arid environments and UV-induced harmful effects and inflammatory responses in human keratinocytes and 3D epithelium equivalents partially through its antioxidant capacity.

Investigation of Structural Characteristics and Solubility Mechanism of Edible Bird Nest: A Mucin Glycoprotein

In this study, the possible solubility properties and water-holding capacity mechanism of edible bird nest (EBN) were investigated through a structural analysis of soluble and insoluble fractions. The protein solubility and the water-holding swelling multiple increased from 2.55% to 31.52% and 3.83 to 14.00, respectively, with the heat temperature increase from 40 °C to 100 °C. It was observed that the solubility of high-Mw protein increased through heat treatment; meanwhile, part of the low-Mw fragments was estimated to aggregate to high-Mw protein with the hydrophobic interactions and disulfide bonds. The increased crystallinity of the insoluble fraction from 39.50% to 47.81% also contributed to the higher solubility and stronger water-holding capacity. Furthermore, the hydrophobic interactions, hydrogen bonds, and disulfide bonds in EBN were analyzed and the results showed that hydrogen bonds with burial polar group made a favorable contribution to the protein solubility. Therefore, the crystallization area degradation under high temperature with hydrogen bonds and disulfide bonds may be the main reasons underlying the solubility properties and water-holding capacity of EBN.

Qualitative and Quantitative Analysis of Edible Bird's Nest Based on Peptide Markers by LC-QTOF-MS/MS

Edible bird's nest (EBN) is an expensive health food. There are many adulterants in the market. It remains challenging to discriminate EBN from its adulterants due to a lack of high-specificity markers. Besides, the current markers are confined to soluble fraction of EBN. Here, both soluble and insoluble fractions were analyzed by LC-QTOF-MS/MS. A total of 26 high-specificity peptides that were specific to EBN were selected as qualitative authentication markers. Among them, 10 markers can discriminate EBN from common adulterants, 13 markers discriminate white EBN from grass EBN/common adulterants, and 3 markers discriminate grass EBN from white EBN/common adulterants. Three of them, which showed high signal abundance (Peak area ≥ 10⁶) and satisfactory linearity (R² ≥ 0.995) with EBN references, were selected as the assay marker; and their peptide sequences were confidently identified by searching database/de novo sequencing. Based on these markers, a qualitative and quantitative analytical method was successfully developed and well-validated in terms of linearity, precision, repeatability, and accuracy. The method was subsequently applied to detect EBN products on the market. The results indicated that more than half of EBN products were not consistent with what the merchants claimed.

Determination and level investigation of 45 hormones in edible bird's nest by solid phase extraction-high performance liquid chromatography-tandem mass spectrometry

建立了固相萃取-高效液相色谱-串联质谱(SPE-HPLC-MS/MS)同时测定食用燕窝中皮质激素、雌激素、雄激素及孕激素等5类45种激素的多残留分析方法。采用乙腈-乙酸乙酯(1∶1, v/v)超声辅助提取、亲水亲脂平衡固相萃取柱净化,甲醇洗脱。分别在正、负电喷雾电离源、多反应监测模式下检测45种激素。正离子模式下的流动相为乙腈-0.1%甲酸水溶液,负离子模式下的流动相为乙腈-水,色谱柱为Phenomenex Kinetex C₁₈柱(100 mm×2.1 mm, 2.6 μm)。在优化条件下,45种激素在0.20~20.0 μg/L范围内线性关系良好,相关系数(R²)≥0.9990,方法的检出限(LOD)为0.04~0.70 μg/kg,定量限(LOQ)为0.16~2.00 μg/kg。按三水平(2.0、4.0、20.0 μg/kg)进行加标回收试验,氟米龙、布地奈德、醛固酮、醋酸氟轻松、炔雌醇的回收率为40.2%~63.6%,可对这5种激素进行定性分析,其余40种激素的平均加标回收率为72.2%~112.3%,相对标准偏差(RSD)为2.5%~11.6%,该方法可对40种激素进行准确定性定量,精密度好,灵敏度高,简便、快速。从2017~2021年,通过研究建立的方法对来自马来西亚、印度尼西亚、泰国和越南等国家的1021个燕窝样品进行监测,仅勃地酮、雄烯二酮、孕酮有检出(大于检出限),其他激素均小于检出限。孕酮检出率为100%,勃地酮、雄烯二酮检出率分别为79%和89%, 3种激素含量范围分别为0.097~3.58、0~0.096和0~1.77 μg/kg。与同为动物源性食品的鸡蛋、纯牛奶、乳制品相比,所有测定的鸡蛋样品中均检出雄烯二酮,含量比其他3类产品略高;勃地酮在4类产品中的含量差别不大,均为微量;孕酮含量在鸡蛋中最高,其次是纯牛奶,燕窝中含量最低。研究结果表明,食用燕窝带入的激素种类少,含量低,对健康影响小。

Anti-Wrinkle Efficacy of Edible Bird's Nest Extract: A Randomized, Double-Blind, Placebo-Controlled, Comparative Study

This study aimed to evaluate skin health's functional improvement, such as wrinkles, elasticity, moisture, and whitening, and safety following the consumption of "edible bird's nest extract" for 12 weeks by women. This single-center, double-blinded, parallel-group, placebo-controlled study included women aged 40-60 years. Our primary purpose was to assess improvement in skin wrinkles, elasticity, and moisture after 12 weeks using an SV700, cutometer, and corneometer, respectively, compared to baseline measurements. Our secondary purpose was to evaluate skin wrinkle, elasticity, and moisture changes at 4 and 8 weeks from baseline using the aforementioned equipment, and measure transdermal water loss and melanin and erythema indexes using a tewameter and mexameter, respectively. Experts performed the visual evaluation of skin wrinkles at 4, 8, and 12 weeks from baseline. The participants were randomly allocated in a 1:1 ratio into the edible bird's nest extract or the placebo group with 43 participants each, where they consumed 100 mg of the extract or placebo, respectively, daily for 12 weeks. The outcomes were measured at every visit. In this study, upon comparing changes in the skin elasticity value between the two intake groups at 12 weeks of ingestion, skin elasticity in the edible bird's nest extract group decreased significantly compared with that in the placebo group. Adverse reactions were absent in both groups. In the case of laboratory test results, changes before and after the ingestion of the extract were within the normal range, thus indicating no clinically significant difference. The edible bird's nest extract was effective in improving skin wrinkles. Moreover, it is beneficial for skin health and can be used as a skin nutritional supplement. Compared with the placebo, the edible bird's nest extract was identified as safe. Clinical Trial Registration: https://cris.nih.go.kr/cris/search/detailSearch.do?search_lang=E&search_page=M&pageSize=10&page=undefined&seq=21007&status=5&seq_group=20330, identifier KCT0006558.

Why the importance of geo-origin tracing of edible bird nests is arising?

Edible bird's nest (EBN) swiftlet existed naturally 48,000 years ago in caves as their natural dwellings. Nowadays, edible bird's nest has become a very important industry due to its high nutritional, medicinal and economic value. Additionally, edible bird's nest has a long quality guarantee period. Obviously, the nutritional components and medicinal functions vary depending on geographical origins. Recently, the global demand for edible bird's nest has markedly increased, accompanied by the increasing attention of all key players of the global food trade system, i.e., producers, consumers, traders and the authorities to obtain safe and high-quality edible bird's nest. Hence, this target can be accomplished via the enforcement of an efficient and universal geo-tracing technique. Current methods of the geo-tracking of edible bird's nest, i.e., automation, physical and analytical techniques have several limitations and all of them fail to discriminate different quality grades of edible bird's nest. Meanwhile, in many studies and applications, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) has proven to be a "cutting edge" technique for greatly enhance food traceability from field to fork through its ability in distinguishing the food products in terms of their quality and safety. This article provides an overview of (1) edible bird's nest as a multiuse strategic food product, (2) quality issues associated with edible bird's nest including implications that the site of acquisition of the edible bird's nest has food safety implications, (3) current regulations and geo-tracking approaches to ensure the safety and quality of edible bird's nest with the special focus on polymerase chain reaction-denaturing gradient gel electrophoresis technique as a vigorous and universal geo-tracing tool to be suggested for edible bird's nest geo-traceability.

Edible Bird's Nest: Recent Updates and Industry Insights Based On Laboratory Findings

Edible bird’s nest (EBN) is a traditional Chinese delicacy made of the saliva of swiftlets found in Southeast Asia. With increasing demands for EBN, quality control of EBN products is important for safe consumption. The processing steps are particularly important for efficient extraction of bioactive compounds. Geographical location, collection place, and harvesting season contribute to differences in nutritional contents in EBN. Concerns regarding presence of adulterant, chemical, and microbial contaminants in EBN as well as authentication and chemical composition measuring methods are discussed in this review. Recent discoveries of beneficial health functions of EBN in antimicrobial and antiviral actions, immunomodulation, cancer prevention and treatment, tissue regeneration, cardiometabolic maintenance, antioxidant action and neuroprotection are also reviewed. Our review provides an update on the recent research on 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) mPa·s to (7.84 ± 0.31) mPa·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 FeSO₄ 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.

Study on sialic acid binding state in stewed bird's nest and optimization of enzymatic extraction of free and oligosaccharide-bound sialic acid

BACKGROUND

As a traditional Chinese health food, edible bird's nest (EBN) has high medicinal value, which is mostly attributed to the high content of sialic acid (SA). SA mainly exists in protein-bound, oligosaccharide-bound and free forms and the binding forms of SA are closely related to the functions of EBN.

OBJECTIVE

To establish a simple but robust method to distinguish and determinate the free and oligosaccharide-bound SA content and the protein-bound SA content, and investigate the changes of SA binding state in EBN during different processing.

METHODS

Protein-bound SA in EBN was separated from other forms of SA by trichloroacetic acid precipitation, and SA content was determined by high performance liquid chromatography (HPLC). The effects of stewing conditions on the distribution of SA in EBN were investigated and response surface methodology was used to explore the optimal conditions for enzymatic extraction of free and oligosaccharide-bound SA from EBN.

RESULTS

The average recoveries of free and oligosaccharide-bound SA and protein-bound SA were 97.82%-98.92% and 94.67%-95.75%. The content of free and oligosaccharide-bound SA in stewed EBN was proportional to the stewing temperature, stewing time and liquid to material ratio, while that of protein-bound SA was inversely proportional to those factors. Through response surface analysis, we found that the optimum technological parameters were as follows: liquid to material ratio was 60: 1, enzymolysis time was 2 h, enzyme dosage was 12000 U/g (alkaline protease), pH was 11, enzymolysis temperature was 60 °C.

CONCLUSION

This method can not only distinguish free and oligosaccharide-bound SA and protein-bound SA effectively, but also determine the contents of them. The results of investigation on stewing conditions and response surface analysis can be used as the theoretical basis for the further pharmacological research of EBN, and can also provide theoretical guidance for the development of EBN products.

HIGHLIGHTS

A method for the determination of free and oligosaccharide-bound SA and protein-bound SA in EBN by HPLC was established, and the extraction process of free and oligosaccharide-bound SA was optimized.

The Authentication and Grading of Edible Bird's Nest by Metabolite, Nutritional, and Mineral Profiling

Edible bird's nest (EBN) produced by Aerodramus fuciphagus has a high demand for nutritional and medicinal application throughout the world. The present study was to evaluate the authentication of a man-made house EBN, which are half cup and stripe-shaped by FTIR. Next, both samples were compared according to their metabolite, nutritional, and mineral composition. The results indicated that the FTIR spectra of both EBN samples were identical and similar to the reference, suggesting the authenticity of the EBN used. The metabolites that contribute to the possible medicinal properties of EBN were found by using GC-MS. The results of the proximate analysis, followed by the standard AOAC method, inferred that both EBN shapes to be rich in crude protein and carbohydrate contents. However, the proximate composition between the half cup and stripe-shaped EBN showed significant differences. Major mineral elements detected were calcium and sodium, and magnesium contents were significantly different between both EBN. Additionally, the half cup and stripe-shaped EBN had a low level of heavy metal content than the maximum regulatory limit as set by the Malaysian Food Act 1983. This study concludes that the nutritional composition varied between the samples and thus suggests that nutrient content should be considered as criteria for the grading requirement of commercialized EBN.

The Anti-Viral and Anti-Inflammatory Properties of Edible Bird's Nest in Influenza and Coronavirus Infections: From Pre-Clinical to Potential Clinical Application

Edible bird's nest (BN) is a Chinese traditional medicine with innumerable health benefits, including anti-viral, anti-inflammatory, neuroprotective, and immunomodulatory effects. A small number of studies have reported the anti-viral effects of EBN against influenza infections using in vitro and in vivo models, highlighting the importance of sialic acid and thymol derivatives in their therapeutic effects. At present, studies have reported that EBN suppresses the replicated virus from exiting the host cells, reduces the viral replication, endosomal trafficking of the virus, intracellular viral autophagy process, secretion of pro-inflammatory cytokines, reorient the actin cytoskeleton of the infected cells, and increase the lysosomal degradation of viral materials. In other models of disease, EBN attenuates oxidative stress-induced cellular apoptosis, enhances proliferation and activation of B-cells and their antibody secretion. Given the sum of its therapeutic actions, EBN appears to be a candidate that is worth further exploring for its protective effects against diseases transmitted through air droplets. At present, anti-viral drugs are employed as the first-line defense against respiratory viral infections, unless vaccines are available for the specific pathogens. In patients with severe symptoms due to exacerbated cytokine secretion, anti-inflammatory agents are applied. Treatment efficacy varies across the patients, and in times of a pandemic like COVID-19, many of the drugs are still at the experimental stage. In this review, we present a comprehensive overview of anti-viral and anti-inflammatory effects of EBN, chemical constituents from various EBN preparation techniques, and drugs currently used to treat influenza and novel coronavirus infections. We also aim to review the pathogenesis of influenza A and coronavirus, and the potential of EBN in their clinical application. We also describe the current literature in human consumption of EBN, known allergenic or contaminant presence, and the focus of future direction on how these can be addressed to further improve EBN for potential clinical application.

Genetic Identification of Edible Bird's Nest in Thailand Based on ARMS-PCR

Edible bird’s nest (EBN) is a popular delicacy in the Asian Pacific region originating from Indonesia, Malaysia, Thailand and Vietnam, which consist of various potential medicine value in Traditional Chinese Medicine (TCM). Thailand is one of the main exporters of EBN. However, the genetic information of EBN, a key part of molecular biology, has yet to be reported in Thailand. It is necessary to explore the genetic information of EBN in Thailand based on a quick and simple method to help protect the rights and interests of consumers. This research aimed to systematically evaluate different methods of extracting EBN DNA to improve the efficiency of the analysis of cytochrome b (Cytb) and NADH dehydrogenase subunit 2 (ND2) gene sequences, the establishment of phylogenetic trees, and the genetic information of EBN in Thailand. Additionally, we aimed to develop a quick and simple method for identifying EBN from different species based on the genetic information and amplification-refractory mutation system PCR (ARMS-PCR). By comparing the four methods [cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), kit and guanidinium isothiocyanate methods] for EBN extraction, we found that the guanidinium isothiocyanate method was the optimal extraction method. Phylogenetic trees generated on the basis of Cytb and ND2 gene analyses showed that 26 samples of house EBN and 4 samples of cave EBN came from Aerodramus fuciphagus and Aerodramus maximus, respectively. In addition, to distinguish different samples from different species of Apodiformes, we designed 4 polymerase chain reaction (PCR) amplification primers based on the ND2 gene sequences of A. fuciphagus and A. maximus. The ARMS-PCR results showed band lengths for A. fuciphagus EBN of 533, 402, and 201 bp, while those for A. maximus EBN were 463, 317, and 201 bp. Collectively, the results showed that ARMS-PCR is a fast and simple method for the genetic identification of EBN based on designing specific original identification primers.