2023 Vol. 38, No. 1
2023, 38(1)
:1-9.
doi: 10.12187/2023.01.001
Abstract:
The effect of ionic concentration on the interaction between gelatin and amylose was investigated by spectroscopic methods. The results showed that ionic concentration could change the hydrophobic microenvironment of gelatin. With different ionic concentration, amylose could quench the endogenous fluorescence of gelatin to different degrees. The quenching mechanism was coupling quenching, which was mainly static quenching. With the increase of ionic concentration, the binding ability of gelatin and amylose was enhanced. In aqueous solution, the forces between gelatin and amylose were mainly van der Waals forces and hydrogen bonds, which were mainly driven by hydrophobic forces after sodium chloride was added. Gelatin-amylose binding caused rearrangement and conformational changes of gelatin, resulting in the change of tyrosine residues and tryptophan residues, and the binding site was closer to the tyrosine residues. The gelatin-amylose interaction was effected by the ionic concentration, the addition of sodium chloride was beneficial to the combination of gelatin and amylose and caused the change of conformation of gelatin.
The effect of ionic concentration on the interaction between gelatin and amylose was investigated by spectroscopic methods. The results showed that ionic concentration could change the hydrophobic microenvironment of gelatin. With different ionic concentration, amylose could quench the endogenous fluorescence of gelatin to different degrees. The quenching mechanism was coupling quenching, which was mainly static quenching. With the increase of ionic concentration, the binding ability of gelatin and amylose was enhanced. In aqueous solution, the forces between gelatin and amylose were mainly van der Waals forces and hydrogen bonds, which were mainly driven by hydrophobic forces after sodium chloride was added. Gelatin-amylose binding caused rearrangement and conformational changes of gelatin, resulting in the change of tyrosine residues and tryptophan residues, and the binding site was closer to the tyrosine residues. The gelatin-amylose interaction was effected by the ionic concentration, the addition of sodium chloride was beneficial to the combination of gelatin and amylose and caused the change of conformation of gelatin.
2023, 38(1)
:10-17,26.
doi: 10.12187/2023.01.002
Abstract:
With yeast cell as research objective, the effects of different amounts of gluten antifreeze polypeptides on yeast cell survival rate, cell morphology, cell membrane damage and leakage of cell contents during the freezing or repeated freezing and thawing process were studied. The results showed that a certain mass concentration (20~40 g/L) of gluten antifreeze polypeptides could improve the survival rate of yeast cells during the freezing or repeated freezing and thawing process. After repeated freezing and thawing 8 times, the cell survival rate in the yeast suspension supplemented with 40 g/L gluten antifreeze polypeptide was the highest, which was 65.63% higher than that in the blank group. Gluten antifreeze polypeptide could slow down the destruction of yeast cells by ice crystals and keep yeast cells relatively intact and smooth surface morphology. The gluten antifreeze polypeptides significantly reduced the proportion of damaged cells during the freezing or repeated freezing and thawing process, and inhibited the leakage of intracellular DNA and GSH to a certain extent. Gluten antifreeze polypeptides improved the survival rate of yeast cells by reducing the adverse effects of ice crystals on cell membranes during the freezing or repeated freezing and thawing process.
With yeast cell as research objective, the effects of different amounts of gluten antifreeze polypeptides on yeast cell survival rate, cell morphology, cell membrane damage and leakage of cell contents during the freezing or repeated freezing and thawing process were studied. The results showed that a certain mass concentration (20~40 g/L) of gluten antifreeze polypeptides could improve the survival rate of yeast cells during the freezing or repeated freezing and thawing process. After repeated freezing and thawing 8 times, the cell survival rate in the yeast suspension supplemented with 40 g/L gluten antifreeze polypeptide was the highest, which was 65.63% higher than that in the blank group. Gluten antifreeze polypeptide could slow down the destruction of yeast cells by ice crystals and keep yeast cells relatively intact and smooth surface morphology. The gluten antifreeze polypeptides significantly reduced the proportion of damaged cells during the freezing or repeated freezing and thawing process, and inhibited the leakage of intracellular DNA and GSH to a certain extent. Gluten antifreeze polypeptides improved the survival rate of yeast cells by reducing the adverse effects of ice crystals on cell membranes during the freezing or repeated freezing and thawing process.
2023, 38(1)
:18-26.
doi: 10.12187/2023.01.003
Abstract:
In order to investigate the effects of hydrophilic colloid (Artemisia sphaerocephala Krasch.gum (ASKG)) on the gelatinization and rheological properties of waxy rice starch, ASKG was mixed with waxy rice starch at different ratio (0.1%, 0.3%, 0.5%, 0.7% and 0.9%).The results showed that the addition of ASKG could increase the gelatinization viscosity and swelling degree of waxy rice starch, and decrease the gel strength and water fluidity of waxy rice starch. Waxy rice starch had the properties of pseudoplastic fluid. The addition of ASKG could increase the apparent viscosity, consistency coefficient (K) and flow characteristic index (n), indicating that ASKG had synergistic thickening effect. ASKG could improve the elastic modulus (G'), viscosity modulus (G″) and loss angle tangent value (tan δ) of waxy rice starch, but the overall performance was to enhance the fluidity of the system.
In order to investigate the effects of hydrophilic colloid (Artemisia sphaerocephala Krasch.gum (ASKG)) on the gelatinization and rheological properties of waxy rice starch, ASKG was mixed with waxy rice starch at different ratio (0.1%, 0.3%, 0.5%, 0.7% and 0.9%).The results showed that the addition of ASKG could increase the gelatinization viscosity and swelling degree of waxy rice starch, and decrease the gel strength and water fluidity of waxy rice starch. Waxy rice starch had the properties of pseudoplastic fluid. The addition of ASKG could increase the apparent viscosity, consistency coefficient (K) and flow characteristic index (n), indicating that ASKG had synergistic thickening effect. ASKG could improve the elastic modulus (G'), viscosity modulus (G″) and loss angle tangent value (tan δ) of waxy rice starch, but the overall performance was to enhance the fluidity of the system.
2023, 38(1)
:27-33.
doi: 10.12187/2023.01.004
Abstract:
Nano-starch with different mass concentration was added into the potato starch-chitosan composites containing citronellol, and the effect of nano-starch mass concentration on the multi-scale structure (the molecular force, crystalline structure, section morphology and water contact angle) and thermal stability were investigated. The results showed that the molecular forces of each component in the composites did not change significantly with the addition of nano-strach. Exfoliated structure was formed with nano-starch and composites matrix, and the whole matrix displayed amorphous. As the mass concentration of nano-starch increased, the surface of composites presented smooth, while the section morphology showed certain wrinkle. The water contact angle increased from (77.50±0.50)° without nano-starch to (85.50±1.25)° with 9.1%, indicating that the hydrophilicity decreased. The characteristic pyrolysis peak temperature of the composites slightly increased, which showed that the thermal stability was slightly improved.
Nano-starch with different mass concentration was added into the potato starch-chitosan composites containing citronellol, and the effect of nano-starch mass concentration on the multi-scale structure (the molecular force, crystalline structure, section morphology and water contact angle) and thermal stability were investigated. The results showed that the molecular forces of each component in the composites did not change significantly with the addition of nano-strach. Exfoliated structure was formed with nano-starch and composites matrix, and the whole matrix displayed amorphous. As the mass concentration of nano-starch increased, the surface of composites presented smooth, while the section morphology showed certain wrinkle. The water contact angle increased from (77.50±0.50)° without nano-starch to (85.50±1.25)° with 9.1%, indicating that the hydrophilicity decreased. The characteristic pyrolysis peak temperature of the composites slightly increased, which showed that the thermal stability was slightly improved.
2023, 38(1)
:34-44.
doi: 10.12187/2023.01.005
Abstract:
Wet alkaline noodles was set as the object, and the changes in the characteristics of the protein and starch characteristics of wet alkaline noodles during processing were investigated. The effects of standing time after oil sprinkle on the quality of wet alkaline noodles were studied. The results indicated that the contents of free sulfhydryl group and low molecular weight protein submit in gluten were decreased, and the content of glutenin macropolymer(GMP) was increased during noodle processing. Pasting properties showed that most viscosity parameters were reduced; relative crystallinity was first decreased and then increased. The lightness in noodle color and hardness in noodle texture were gradually reduced, but the content of less-strongly bound water in water distribution was increased. Moreover, as the standing time after oil sprinkle prolonged, the lightness of noodle was reduced, noodle hardness was first increased and then reduced, and the score of sensory evaluation was enhanced.
Wet alkaline noodles was set as the object, and the changes in the characteristics of the protein and starch characteristics of wet alkaline noodles during processing were investigated. The effects of standing time after oil sprinkle on the quality of wet alkaline noodles were studied. The results indicated that the contents of free sulfhydryl group and low molecular weight protein submit in gluten were decreased, and the content of glutenin macropolymer(GMP) was increased during noodle processing. Pasting properties showed that most viscosity parameters were reduced; relative crystallinity was first decreased and then increased. The lightness in noodle color and hardness in noodle texture were gradually reduced, but the content of less-strongly bound water in water distribution was increased. Moreover, as the standing time after oil sprinkle prolonged, the lightness of noodle was reduced, noodle hardness was first increased and then reduced, and the score of sensory evaluation was enhanced.
2023, 38(1)
:45-53.
doi: 10.12187/2023.01.006
Abstract:
Shandong tobacco leaves were fermented by Enterobacter cloacae F8-2 and Acinetobacter nosocomialis 7S-2 mixed bacteria. The sensory quality, chemical composition and chemical composition of tobacco smoke and microbial community on tobacco leaf surface before and after fermentation were studied. The results showed that when Enterobacter and Acinetobacter were mixed in 1:1 fermentation for 24 h, the aroma of the tobacco leaf increased and the impurity of the tobacco leaf decreased most significantly. After fermentation, methylheptenone, dihydrotomarone and 5-methylfurfural increased by 89.22%, 35.67% and 33.93%, respectively. Nerolol, solanone and acyl alcohol in tobacco smoke increased by 78.01%, 46.83% and 45.95%, respectively. Mixed fermentation had a great impact on the bacterial community on the surface of tobacco leaves, and the microorganisms cooperated with each other in fermentation and symbiosis. At the same time, Enterobacter and Acinetobacter may be related to the production of aromatic substances such as benzaldehyde and methyl heptene ketone.
Shandong tobacco leaves were fermented by Enterobacter cloacae F8-2 and Acinetobacter nosocomialis 7S-2 mixed bacteria. The sensory quality, chemical composition and chemical composition of tobacco smoke and microbial community on tobacco leaf surface before and after fermentation were studied. The results showed that when Enterobacter and Acinetobacter were mixed in 1:1 fermentation for 24 h, the aroma of the tobacco leaf increased and the impurity of the tobacco leaf decreased most significantly. After fermentation, methylheptenone, dihydrotomarone and 5-methylfurfural increased by 89.22%, 35.67% and 33.93%, respectively. Nerolol, solanone and acyl alcohol in tobacco smoke increased by 78.01%, 46.83% and 45.95%, respectively. Mixed fermentation had a great impact on the bacterial community on the surface of tobacco leaves, and the microorganisms cooperated with each other in fermentation and symbiosis. At the same time, Enterobacter and Acinetobacter may be related to the production of aromatic substances such as benzaldehyde and methyl heptene ketone.
2023, 38(1)
:54-62.
doi: 10.12187/2023.01.007
Abstract:
After dilution centrifugation, enrichment culture, and gradient plate screening, a series of strains that can adapt to concentrated tobacco waste water extract (TWE) and exhibit metabolic activity were isolated from concentrated TWE during the paper-making reconstituted tobacco process. Their morphological, physiological and biochemical characteristics were identified. The isolated strains were added into concentrated TWE for fermentation. The growth and metabolism characteristics and their effects on the composition of metabolites in TWE were investigated. The results showed that a yeast strain MC-9A1 resistant to high stress was isolated from concentrated TWE, which belonged to the species Zygosaccharomyces bailii. The strain MC-9A1 could grow in concentrated TWE and carried out normal metabolic activities, consuming a lot of sugar. At the same time, MC-9A1 consumed a large number of strongly polar substances and a small number of moderately polar substances in concentrated TWE, and generated a large number of weakly polar or non-polar substances. More than 310 metabolites were significantly up-regulated or down-regulated. For example, acetamide and xylitol increased significantly, while arbutin and D-galacturonic acid decreased significantly. The sensory evaluation results showed that the sensory effect was improved by fermentation of MC-9A1 in concentrated TWE, which increased aroma quality, while decreased odor and the residual.
After dilution centrifugation, enrichment culture, and gradient plate screening, a series of strains that can adapt to concentrated tobacco waste water extract (TWE) and exhibit metabolic activity were isolated from concentrated TWE during the paper-making reconstituted tobacco process. Their morphological, physiological and biochemical characteristics were identified. The isolated strains were added into concentrated TWE for fermentation. The growth and metabolism characteristics and their effects on the composition of metabolites in TWE were investigated. The results showed that a yeast strain MC-9A1 resistant to high stress was isolated from concentrated TWE, which belonged to the species Zygosaccharomyces bailii. The strain MC-9A1 could grow in concentrated TWE and carried out normal metabolic activities, consuming a lot of sugar. At the same time, MC-9A1 consumed a large number of strongly polar substances and a small number of moderately polar substances in concentrated TWE, and generated a large number of weakly polar or non-polar substances. More than 310 metabolites were significantly up-regulated or down-regulated. For example, acetamide and xylitol increased significantly, while arbutin and D-galacturonic acid decreased significantly. The sensory evaluation results showed that the sensory effect was improved by fermentation of MC-9A1 in concentrated TWE, which increased aroma quality, while decreased odor and the residual.
2023, 38(1)
:63-70.
doi: 10.12187/2023.01.008
Abstract:
The bacterial community composed by Bacillus subtilis and Lactobacillus plantarum was used to ferment tobacco stem, the degradation of cell wall components, the structural properties and thermal reaction characteristics, the changes of aroma components and bacterial community structure of tobacco stem by solid-state anaerobic fermentation were studied. Results showed that after 5 days of anaerobic fermentation, the degradation rate of lignin in tobacco stem was 50.55%. Degradation of lignin was enhanced mainly by the breakdown of covalent bond between lignin and hemicellulose, demethylation, benzene ring decomposition, etc. After anaerobic fermentation, the pyrolysis weight loss of tobacco stem was increased by 4.85% and the maximum pyrolysis rate was increased by 13.28%, which was more conducive to the pyrolysis reaction. The content of total aroma components in tobacco stem after fermentation was increased by 7.88%, and the content of degraded carotene products increased significantly. In addition to Bacillus subtilis and Lactobacillus plantarum, the relative abundance of functional bacteria related to lignin degradation was greatly increased, and the degradation and transformation of tobacco stem lignin was improved by the synergistic fermentation with microbial community.
The bacterial community composed by Bacillus subtilis and Lactobacillus plantarum was used to ferment tobacco stem, the degradation of cell wall components, the structural properties and thermal reaction characteristics, the changes of aroma components and bacterial community structure of tobacco stem by solid-state anaerobic fermentation were studied. Results showed that after 5 days of anaerobic fermentation, the degradation rate of lignin in tobacco stem was 50.55%. Degradation of lignin was enhanced mainly by the breakdown of covalent bond between lignin and hemicellulose, demethylation, benzene ring decomposition, etc. After anaerobic fermentation, the pyrolysis weight loss of tobacco stem was increased by 4.85% and the maximum pyrolysis rate was increased by 13.28%, which was more conducive to the pyrolysis reaction. The content of total aroma components in tobacco stem after fermentation was increased by 7.88%, and the content of degraded carotene products increased significantly. In addition to Bacillus subtilis and Lactobacillus plantarum, the relative abundance of functional bacteria related to lignin degradation was greatly increased, and the degradation and transformation of tobacco stem lignin was improved by the synergistic fermentation with microbial community.
2023, 38(1)
:71-78,89.
doi: 10.12187/2023.01.009
Abstract:
By high-throughput sequencing and metabolomics, the physicochemical metabolites and microbial community structure during cigar tobacco fermentation were analyzed, and then functional microorganisms and cooccurring taxa were identified by correlation analysis and network analysis to reveal the impact of microbiota on the quality of cigar tobacco. The results showed that the relative abundances of the dominant microbial genera Staphylococcus and Aspergillus increased first and then decreased during fermentation, and dominated the bacterial and fungal communities on the 21st day, respectively. Aspergillus, Staphylococcus, Filobasidium might have direct or indirect effects on the production of total and reducing sugars. Bacillus might have degradation effect on nitrogenous substances. In particular, Candida, as co-occurring taxa and biomarker in the later stage of fermentation, could not only degrade nitrogenous substances, synthesize flavor substances, but also play an important role in maintaining the stability of microbial community structure.
By high-throughput sequencing and metabolomics, the physicochemical metabolites and microbial community structure during cigar tobacco fermentation were analyzed, and then functional microorganisms and cooccurring taxa were identified by correlation analysis and network analysis to reveal the impact of microbiota on the quality of cigar tobacco. The results showed that the relative abundances of the dominant microbial genera Staphylococcus and Aspergillus increased first and then decreased during fermentation, and dominated the bacterial and fungal communities on the 21st day, respectively. Aspergillus, Staphylococcus, Filobasidium might have direct or indirect effects on the production of total and reducing sugars. Bacillus might have degradation effect on nitrogenous substances. In particular, Candida, as co-occurring taxa and biomarker in the later stage of fermentation, could not only degrade nitrogenous substances, synthesize flavor substances, but also play an important role in maintaining the stability of microbial community structure.
2023, 38(1)
:79-89.
doi: 10.12187/2023.01.010
Abstract:
The dynamic changes of surface microorganisms were monitored during the fermentation of tobacco by Enterobacter hormaechei F8-1, and mechanism of tobacco fermentation by F8-1 was studied combined with neutral aroma components of tobacco leaves and sensory analysis. The results showed that after fermentation the aroma quality and sweet taste were improved, the offensive odor and irritation were reduced. The contents of megastigmatrienone, solanone, (E)-β-damascenone and dihydrodamascenone were increased respectively by 37.40%, 59.87%, 53.02% and 46.61%. During the fermentation, the predominant species were E hormaechei F8-1, Pseudomonas aeruginosa, and Enterobacter cloacae; the highest number of glycoside hydrolases accounted for 78.3% of the microbial carbohydrate-active enzymes on the surface of the tobacco filaments during fermentation; the abundance of Enterobacter spp. was positively correlated with the content of solanone, megastigmatrienone, (E)-β-damascenone and dihydrodamascenone, and the abundance of glycoside hydrolase family 1 (GH1) was positively correlated with the content of solanone, megastigmatrienon and farnesylacetone. Glycoside hydrolases in the GH1 might be key factors for sensory enhancement after tobacco fermentation.
The dynamic changes of surface microorganisms were monitored during the fermentation of tobacco by Enterobacter hormaechei F8-1, and mechanism of tobacco fermentation by F8-1 was studied combined with neutral aroma components of tobacco leaves and sensory analysis. The results showed that after fermentation the aroma quality and sweet taste were improved, the offensive odor and irritation were reduced. The contents of megastigmatrienone, solanone, (E)-β-damascenone and dihydrodamascenone were increased respectively by 37.40%, 59.87%, 53.02% and 46.61%. During the fermentation, the predominant species were E hormaechei F8-1, Pseudomonas aeruginosa, and Enterobacter cloacae; the highest number of glycoside hydrolases accounted for 78.3% of the microbial carbohydrate-active enzymes on the surface of the tobacco filaments during fermentation; the abundance of Enterobacter spp. was positively correlated with the content of solanone, megastigmatrienone, (E)-β-damascenone and dihydrodamascenone, and the abundance of glycoside hydrolase family 1 (GH1) was positively correlated with the content of solanone, megastigmatrienon and farnesylacetone. Glycoside hydrolases in the GH1 might be key factors for sensory enhancement after tobacco fermentation.
2023, 38(1)
:90-100.
doi: 10.12187/2023.01.011
Abstract:
In torder to explore the mechanisms of fermentative medium on the flavor enrichment and quality improvement of cigar tobacco leaves, the influence of fermentative medium on conventional chemical components, non-volatile organic acids, aroma components and microbial communities of cigar tobacco leaves was analyzed. The results showed that the contents of alkaloids in control group and experimental group decreased by 13.42% and 15.80%, respectively. The addition of fermentative medium delayed the degradation of alkaloids and reduced sugars in the early stage of fermentation. The organic acid composition in medium-group during 14~21 days was beneficial to improve the mellowness and reduce the stimulation of cigar tobacco leaves. The contents of aroma compounds and ketone aromatic compounds increased by 10.10% and 19.20% with the addition fermentative medium, respectively. During the fermentation process of 3 d, the content of aroma substances increased first and then decreased, indicating that excessive fermentation was not conducive to the accumulation of aroma components, and 21 days might be the optimal fermentation period. Fermentative medium could improve the diversity of microbial community in cigar tobacco leaves, and delay the succession rate of bacterial community. Besides, the succession of bacterial communities slowed down. As a result, the metabolic processes of alkaloids and sugars were changed, and the content of aroma components in cigar tobacco leaves increased so as to improve the quality of cigar.
In torder to explore the mechanisms of fermentative medium on the flavor enrichment and quality improvement of cigar tobacco leaves, the influence of fermentative medium on conventional chemical components, non-volatile organic acids, aroma components and microbial communities of cigar tobacco leaves was analyzed. The results showed that the contents of alkaloids in control group and experimental group decreased by 13.42% and 15.80%, respectively. The addition of fermentative medium delayed the degradation of alkaloids and reduced sugars in the early stage of fermentation. The organic acid composition in medium-group during 14~21 days was beneficial to improve the mellowness and reduce the stimulation of cigar tobacco leaves. The contents of aroma compounds and ketone aromatic compounds increased by 10.10% and 19.20% with the addition fermentative medium, respectively. During the fermentation process of 3 d, the content of aroma substances increased first and then decreased, indicating that excessive fermentation was not conducive to the accumulation of aroma components, and 21 days might be the optimal fermentation period. Fermentative medium could improve the diversity of microbial community in cigar tobacco leaves, and delay the succession rate of bacterial community. Besides, the succession of bacterial communities slowed down. As a result, the metabolic processes of alkaloids and sugars were changed, and the content of aroma components in cigar tobacco leaves increased so as to improve the quality of cigar.
2023, 38(1)
:101-109.
doi: 10.12187/2023.01.012
Abstract:
The community structure and functional gene succession of surface microorganisms in Yunnan tobacco leaves at different aging stages were analyzed based on metagenomics. The changes of neutral aroma components during the aging of tobacco leaves were traced. The correlation between microorganisms, enzyme gene and neutral aroma components was explored, and a screening method for tobacco-derived functional microorganisms was established. The results showed at the 3rd, 6th, 9th and 12th month of aging, the dominant genera were Sphingomonas, Enterobacter, Pantoea, and Acinetobacter,respectively. The neutral aroma components in tobacco leaves such as benzyl alcohol, phenylacetaldehyde, 2-acetylpyrrole, solanone, damascenone and megastigmatrienone had an increasing trend. Furfural and β-cyclocitral had a first increase and then decrease trend. The content of hydrocarbons decreased. Klebsiella had a significant positive correlation with β-damascenone, megastrienone and solanone. Acinetobacter had a significant positive correlation with 2-acetylfuran, linalool and megastrienone. Phenylethylaldehyde, benzaldehyde, furfuryl alcohol and cypressene were negatively correlated with almost all carbohydrate synthase, and most glycosidase families were positively correlated with neutral aroma components. A total of 75 strains of microorganisms were screened during tobacco leaf aging, and the microbial types and functions were basically consistent with the results of metagenome analysis, indicating that the analysis results of metagenome could guide microbial screening, enhance the purpose of screening, and improve screening efficiency.
The community structure and functional gene succession of surface microorganisms in Yunnan tobacco leaves at different aging stages were analyzed based on metagenomics. The changes of neutral aroma components during the aging of tobacco leaves were traced. The correlation between microorganisms, enzyme gene and neutral aroma components was explored, and a screening method for tobacco-derived functional microorganisms was established. The results showed at the 3rd, 6th, 9th and 12th month of aging, the dominant genera were Sphingomonas, Enterobacter, Pantoea, and Acinetobacter,respectively. The neutral aroma components in tobacco leaves such as benzyl alcohol, phenylacetaldehyde, 2-acetylpyrrole, solanone, damascenone and megastigmatrienone had an increasing trend. Furfural and β-cyclocitral had a first increase and then decrease trend. The content of hydrocarbons decreased. Klebsiella had a significant positive correlation with β-damascenone, megastrienone and solanone. Acinetobacter had a significant positive correlation with 2-acetylfuran, linalool and megastrienone. Phenylethylaldehyde, benzaldehyde, furfuryl alcohol and cypressene were negatively correlated with almost all carbohydrate synthase, and most glycosidase families were positively correlated with neutral aroma components. A total of 75 strains of microorganisms were screened during tobacco leaf aging, and the microbial types and functions were basically consistent with the results of metagenome analysis, indicating that the analysis results of metagenome could guide microbial screening, enhance the purpose of screening, and improve screening efficiency.
2023, 38(1)
:110-118.
doi: 10.12187/2023.01.013
Abstract:
Adhesive polydopamine nanocapsules containing hexamidine diisethionate (PDA@HD nanocapsules) were prepared using W1/O/W2 emulsion templating to enhance wet adhesion capacity of HD. Thereafter, the morphological structure, loading and release properties, adhesion properties and acute toxicity to zebrafish embryos of PDA were investigated. The results showed that the PDA@HD nanocapsules were spherical with a distinct core-shell structure whose average particle size was 353 nm. The loading ratio of PDA@HD nanocapsules could be effectively increased by increasing the concentration of HD in W1 phase of W1/O/W2 emulsion. Specifically, by increasing the concentration of HD to 18 mg/mL,the loading ratio of PDA@HD nanocapsules increased to 17.1%. The release of HD in PDA@HD nanocapsules exhibited a clear pH dependence and PDA@HD nanocapsules showed better release properties in acidic environment. The adhesion force of PDA@HD nanocapsules was effectively increased about 3 times that of HD. The PDA@HD nanocapsules reduced the acute toxicity to zebrafish embryos. When the concentration of HD in PDA@HD nanocapsules was 0.5 mg/mL, all zebrafish embryos survived till 96 hpf.
Adhesive polydopamine nanocapsules containing hexamidine diisethionate (PDA@HD nanocapsules) were prepared using W1/O/W2 emulsion templating to enhance wet adhesion capacity of HD. Thereafter, the morphological structure, loading and release properties, adhesion properties and acute toxicity to zebrafish embryos of PDA were investigated. The results showed that the PDA@HD nanocapsules were spherical with a distinct core-shell structure whose average particle size was 353 nm. The loading ratio of PDA@HD nanocapsules could be effectively increased by increasing the concentration of HD in W1 phase of W1/O/W2 emulsion. Specifically, by increasing the concentration of HD to 18 mg/mL,the loading ratio of PDA@HD nanocapsules increased to 17.1%. The release of HD in PDA@HD nanocapsules exhibited a clear pH dependence and PDA@HD nanocapsules showed better release properties in acidic environment. The adhesion force of PDA@HD nanocapsules was effectively increased about 3 times that of HD. The PDA@HD nanocapsules reduced the acute toxicity to zebrafish embryos. When the concentration of HD in PDA@HD nanocapsules was 0.5 mg/mL, all zebrafish embryos survived till 96 hpf.
2023, 38(1)
:119-126.
doi: 10.12187/2023.01.014
Abstract:
Based on the application prospects of virtual screening for the discovery of cosmetic efficacy ingredients, the primary methods of virtual screening were reviewed, the development trends of virtual screening in recent years and its application cases in cosmetic efficacy ingredients were overviewed. It was concluded that virtual screening had ligand-based and receptor-based methods. The hybrid method combining diverse virtual screening was becoming increasingly used in bioactive compounds discovery, and it had achieved initial success in the functional ingredients, such as whitening, anti-acne, anti-aging, etc. However, virtual screening was still in the stage of continuous development and improvement, some lead compounds found by virtual screening had low transdermal absorption rate, and the external application characteristics of efficacy ingredients were not considered. In the future, the skin permeability and safety risk assessment of cosmetic efficacy ingredients should be incorporated into the principles of virtual screening, and the virtual screening methods should be selected reasonably, in order to promote the practical application of virtual screening in the development of cosmetics efficacy ingredients.
Based on the application prospects of virtual screening for the discovery of cosmetic efficacy ingredients, the primary methods of virtual screening were reviewed, the development trends of virtual screening in recent years and its application cases in cosmetic efficacy ingredients were overviewed. It was concluded that virtual screening had ligand-based and receptor-based methods. The hybrid method combining diverse virtual screening was becoming increasingly used in bioactive compounds discovery, and it had achieved initial success in the functional ingredients, such as whitening, anti-acne, anti-aging, etc. However, virtual screening was still in the stage of continuous development and improvement, some lead compounds found by virtual screening had low transdermal absorption rate, and the external application characteristics of efficacy ingredients were not considered. In the future, the skin permeability and safety risk assessment of cosmetic efficacy ingredients should be incorporated into the principles of virtual screening, and the virtual screening methods should be selected reasonably, in order to promote the practical application of virtual screening in the development of cosmetics efficacy ingredients.
Journal Information
Founded in 1986， bimonthly
Administered by：The Education Department Henan Province
Sponsored by：Zhengzhou University of Light Industry
Editor-in-chief：Wei Shizhong
Executive Editor-in-Chief：Zou Lin
Deputy Editor-in-Chief：Qu Shuanghong
Edited & published by：Editorial Department of Journal of Light Industry
CN 41-1437/TS
ISSN 2096-1553
Address：136 Science Avenue, Zhengzhou City, Henan Province, China
Postal Code：450001
Tel：(086)0371-86608635
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