scholarly journals Establishment and Characterization of Stable Zein/Glycosylated Lactoferrin Nanoparticles to Enhance the Storage Stability and in vitro Bioaccessibility of 7,8-Dihydroxyflavone

2022 ◽  
Vol 8 ◽  
Author(s):  
Yufeng Chen ◽  
Xiaojing Gao ◽  
Shucheng Liu ◽  
Qiuxing Cai ◽  
Lijun Wu ◽  
...  

In this work, the lactoferrin (LF) was glycosylated by dextran (molecular weight 10, 40, and 70 kDa, LF 10K, LF 40K, and LF 70K) via Maillard reaction as a stabilizer to establish zein/glycosylated LF nanoparticles and encapsulate 7,8-dihydroxyflavone (7,8-DHF). Three zein/glycosylated LF nanoparticles (79.27–87.24 nm) with low turbidity (<0.220) and polydispersity index (PDI) (<0.230) were successfully established by hydrophobic interactions and hydrogen bonding. Compared with zein/LF nanoparticles, zein/glycosylated LF nanoparticles further increased stability to ionic strength (0–500 mM NaCl) at low pH conditions. Zein/glycosylated LF nanoparticles had nanoscale spherical shape and glycosylated LF changed surface morphology of zein nanoparticles. Besides, encapsulated 7,8-DHF exhibited an amorphous state inside zein/glycosylated LF nanoparticles. Most importantly, zein/glycosylated LF nanoparticles had good water redispersibility, high encapsulation efficiency (above 98.50%), favorable storage stability, and bioaccessibility for 7,8-DHF, particularly LF 40K. Collectively, the above research provides a theoretical reference for the application of zein-based delivery systems.

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Farzaneh Lotfipour ◽  
Shahla Mirzaeei ◽  
Maryam Maghsoodi

This paper describes preparation and characterization of beads of alginate and psyllium containing probiotic bacteria ofLactobacillus acidophilusDMSZ20079. Twelve different formulations containing alginate (ALG) and alginate-psyllium (ALG-PSL) were prepared using extrusion technique. The prepared beads were characterized in terms of size, morphology and surface properties, encapsulation efficiency, viabilities in acid (pH 1.8, 2 hours) and bile (0.5% w/v, 2 hours) conditions, and release in simulated colon pH conditions. The results showed that spherical beads with narrow size distribution ranging from1.59±0.04to1.67±0.09 mm for ALG and from1.61±0.06to1.80±0.07mm for ALG-PSL with encapsulation efficiency higher than 98% were achieved. Furthermore, addition of PSL into ALG enhanced the integrity of prepared beads in comparison with ALG formulations. The results indicated that incorporation of PSL into alginate beads improved viability of the bacteria in acidic conditions as well as bile conditions. Also, stimulating effect of PSL on the probiotic bacteria was observed through 20-hour incubation in simulated colonic pH solution. According to ourin vitrostudies, PSL can be a suitable polymer candidate for partial substitution with ALG for probiotic coating.


Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2629
Author(s):  
Yufeng Chen ◽  
Jingchong Peng ◽  
Yueqi Wang ◽  
Daniel Wadhawan ◽  
Lijun Wu ◽  
...  

In this study, two polysaccharides [sodium alginate (ALG) and sodium carboxymethyl cellulose (CMC)] were selected to establish zein/sophorolipid/ALG (ALG/S/Z) and zein/sophorolipid/ALG (CMC/S/Z) nanoparticles to encapsulate 7,8-dihydroxyflavone (7,8-DHF), respectively. The results showed that polysaccharide types significantly affected performance of ternary nanoparticles, including CMC/S/Z possessed lower polydispersity index, particle size and turbidity, but higher zeta potential, encapsulation efficiency and loading capacity compared to ALG/S/Z. Compared to zein/sophorolipid nanoparticles (S/Z), both ALG/S/Z and CMC/S/Z had better stability against low pH (pH 3~4) and high ionic strengths (150~200 mM NaCl). Hydrophobic effects, electrostatic interactions and hydrogen bonding were confirmed in ternary nanoparticles fabrication via Fourier-transform infrared spectroscopy. Circular dichroism revealed that CMC and ALG had no evident impact on secondary structure of zein in S/Z, but changed surface morphology of S/Z as observed by scanning electron microscope. Encapsulated 7,8-DHF exhibited an amorphous state in ternary nanoparticles as detected by X-ray diffraction and differential scanning calorimetry. Furthermore, compared to S/Z, ALG/S/Z, and CMC/S/Z remarkably improved the storage stability and bioaccessibility of 7,8-DHF. CMC/S/Z possessed a greater storage stability for 7,8-DHF, however, ALG/S/Z exhibited a better in vitro bioaccessibility of 7,8-DHF. This research provides a theoretical reference for zein-based delivery system application.


NANO ◽  
2013 ◽  
Vol 08 (04) ◽  
pp. 1350042 ◽  
Author(s):  
JING WANG ◽  
LI GUO ◽  
LI FANG MA

In this paper, we firstly synthesized glycyrrhetinic acid-modified double amino-terminated poloxamer 188 (GA–NH–POLO–NH–GA). The structure of the synthesized compound was confirmed by 1H-NMR and Fourier transform infrared (FT-IR) spectroscopy. Then the nanoparticles composed of GA–NH–POLO–NH–GA/chitosan (GA–NH–POLO–NH–GA/CTS) were prepared by an ionic gelation process. The characterization of the nanoparticles was measured by dynamic light scattering (DLS) and scanning electron microscope (SEM). The results showed that the nanoparticles were well dispersed with a spherical shape and the particle size was distributed between 100 nm and 300 nm. The cytotoxicity based on MTT assay against cells (QGY-7703 cells and L929 cells) showed that the nanoparticles had low toxicity and good biocompatibility. The encapsulation efficiency and drug loading of 5-fluorouracil-loaded nanoparticles (5-FU nanoparticles) were measured by high-performance liquid chromatography (HPLC) and fluorescence spectroscopy, ultraviolet-visible (UV-vis) absorbance. The encapsulation of 5-Fu-loaded CTS nanoparticles was 12.8% and the drug loading was 2.9%, while the encapsulation of 5-Fu-loaded GA–NH–POLO–NH–GA/CTS nanoparticles was 20.9% and the drug loading was 3.36%. The release profile showed that the GA–NH–POLO–NH–GA/CTS nanoparticles were available for sustained release of 5-Fu. The GA–NH–POLO–NH–GA/CTS nanoparticles have a higher affinity to the QGY-7703 cells, so indicated that the GA–NH–POLO–NH–GA/CTS nanoparticles have the capacity of liver-targeting in vitro.


Radiocarbon ◽  
2008 ◽  
Vol 50 (2) ◽  
pp. 289-307 ◽  
Author(s):  
N R Rebollo ◽  
I Cohen-Ofri ◽  
R Popovitz-Biro ◽  
O Bar-Yosef ◽  
L Meignen ◽  
...  

Chemical and structural similarities between poorly preserved charcoal and its contaminants, as well as low radiocarbon concentrations in old samples, complicate 14C age determinations. Here, we characterize 4 fossil charcoal samples from the late Middle Paleolithic and early Upper Paleolithic strata of Kebara Cave, Israel, with respect to the structural and chemical changes that occur when they are subjected to the acid-base-acid (ABA) treatment. Differential thermal analysis and TEM show that acid treatment disrupts the structure, whereas alkali treatment results in the reformation of molecular aggregates. The major changes are ascribed to the formation of salt bridges at high pH and the disruption of the graphite-like crystallites at low pH. Weight losses during the treatments are consistently greater for older samples, implying that they are less well preserved. Based on the changes observed in vitro due to pH fluctuations, various methods for removing contamination, as well as a mechanism for preferential preservation of charcoal in nature, are proposed.


2017 ◽  
Vol 4 (2) ◽  
pp. 263
Author(s):  
Ida Ayu Ketut Ariningsih ◽  
Yan Ramona ◽  
Nyoman Semadi Antara

Candidacies in female reproductive tract are mainly caused by Candida albicans. This infection often causes serious problems, particularly on their reproductive tract (genital part). Until recently, control of this infection has relied on the use of antibiotics. However due to numerous bad side effects of antibiotics, lactic acid bacteria have been proposed as an alternative method to control the growth of Candida albicans. Therefore, this research was aimed to isolate, screen, and characterize lactic acid bacterial isolates (LAB) antagonistic against Candida albicans (the causative agent of candidacies infection in reproductive tract of human). LABs were isolated from various fermented foods, such as tape ketan and kimchi. Isolation of LABs was conducted by applying dilution and spread plate method on MRS agar medium supplemented with BCP indicator to distinguish LABs from non acid-producing bacteria. Colonies with indication to produce acid were screened for antagonistic activity against C. albicans on MRS agar and followed by characterization of those isolates (Gram stain, catalase production test, oxydase production, gas production test, resistance test to low pH conditions and to high level of NaDC (sodium deoxicolic), and test for ability to convert colic acid (CA) into deoxicolic acid (DCA)). The results showed that 46 LAB isolates were successfully isolated from samples of tape ketan and kimchi. Among those, 7 isolates showed antagonistic activity against C. albicans in in vitro tests. All these 7 candidates were also found to be resistance to low pH conditions (up to pH 2) and to high level of NaDC (up to 0.6 mM). Four most potential isolates were further testes for ability to convert colic acid into deoxycolic acid and none showed positive result, indicating that they all showed initial potential and safe for future human probiotic development (especially to be used to treat patients infected by C. albicans).


Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1133 ◽  
Author(s):  
Zhu Zhu ◽  
Tiantian Min ◽  
Xueji Zhang ◽  
Yongqiang Wen

Thymol has been shown to be a safe and effective broad-spectrum antimicrobial agent that can be used as a food preservative. However, its volatile characteristics and strong odor limit its use in food products. The microencapsulation of this essential oil in biopolymers could overcome these disadvantages. In this work, thymol-loaded poly(lactide-co-glycolide) (PLGA) microparticles were successfully prepared and the optimal encapsulation efficiency was obtained at 20% (w/w) thymol. Microparticles containing thymol presented a spherical shape and smooth surface. Microencapsulation significantly improved the thermal and storage stability of thymol. In vitro release profiles demonstrated an initial fast release followed by a slow and sustained release. Thymol-loaded microparticles had strong antibacterial activity against Escherichia coli and Staphylococcus aureus, and the effectiveness of their antibacterial properties was confirmed in a milk test. Therefore, the thymol-loaded microparticles show great potential for use as an antimicrobial and as preservation additives in food.


2013 ◽  
Vol 684 ◽  
pp. 57-62 ◽  
Author(s):  
Zhi Hua Xing

Folic acid-chitosan (FA-CTS) and 10-hydroxycamptothecin (HCPT)-loaded folate-conjugated chitosan (FA-CTS/HCPT) microspheres were prepared by the ionic crosslinking method.The morphological characteristics of microspheres were examined using a scanning electron microscope (SEM). The average particle size and size distribution were determined by dynamic light scattering. The drug encapsulation efficiency (EE) , loading capacity (LC)and release characteristics in vitro were determined using ultraviolet spectrophotometer.The results shown that the microspheres are uniform spherical and regular with a size between 19.79 and81.40μm.Optimized preparation parameters lead to the successful preparation of hydroxycamptothecin-loaded folate-conjugated chitosan microspheres characterized with encapsulation efficiency and loading capacity up to (86.8±0.1)% and 20.6±0.3 % respectively. More then 90% of 10-hydroxycamptothecin was released from microspheres in 4 h at artificial gastric juice, 8h at artificial small intestinal fluid with a good delayed release effect.


1999 ◽  
Vol 4 (2) ◽  
pp. 19
Author(s):  
K.P. Akhtar ◽  
M. Asif ◽  
M.A. Khan ◽  
M.J. Jaskani ◽  
I.A. Khan

Mango malformation occurs in most mango growing regions of the world. Floral and vegetative malformation have been reported. There is general agreement that the fungal pathogen Fusarium moniliforme var. subglutinans or Fusarium subglutinans is the causal agent. Healthy and malformed samples of both floral and vegetative tissues were collected from different varieties of mango grown in several locations to verify the association of F.moniliforme with mango malformation disease in Pakistan. The fungus was isolated and cultured. Frequency of fungal association with the disease ranged between 90- 94%, There was less recovery of fungus from asymptomatic tissue (12- 15%). There was no difference among the commercial mango varieties in the level of susceptibility to this disease. However, seedling germplasm and land races showing resistance to mango malformation were identified. The in vitro growth characters of the fungus were determined on different culture media, at varying temperatures, light and pH conditions. Mycelial growth on potato dextrose agar was better than nine other media tested. At pH 7.00, the ideal temperature for growth was between 25-30° C. Normally, the malformation is not controlled by fungicide application. The in vitro sensitivity of fungus to six fungicides at three concentrations was determined to seek potential means of chemical control.


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