Lyophilization Process of Hydroxypropyl Tetrahydropyrantriol Liposomes

[Objectives]To enhance the skin permeability of hydroxypropyl tetrahydropyrantriol and provide a reference for the subsequent prevention or treatment of skin aging.[Methods]The lyophilization process of hydroxypropyl tetrahydropyrantriol liposomes was investigated using a single factor method,and a quality evaluation system was established based on the appearance,particle size,PDI,and re-dispersibility of the lyophilized samples.[Results]The lyophilization process of hydroxypropyl tetrahydropyrantriol liposomes was determined by single factor experiments.The pre-freezing period was 16 h at-80℃,the total drying time was 36 h,and the addition of 10%mannitol-sucrose was used as the lyoprotectant.[Conclusions]The product prepared by the lyophilization method exhibits a fluffy and full appearance,with minimal shrinkage and collapse.The volume remains consistent before and after lyophilization,and the re-dispersibility is satisfactory.The re-dissolution process is rapid,and the particle size and polydispersity index(PDI)remain largely unchanged before and after lyophilization.

Biological Characteristics of Trehalose and Its Protective Effect on Food Fermentation Starters during Lyophilization

This paper reviewed the unique biological function of trehalose and its mechanism of stabilizing biological macromolecules and the research progress in the protective effect of trehalose on lactic acid bacteria fermentation starters during lyophilization in food production.The application of trehalose in food industry was prospected.

Numerical Evaluation of Residual Water Content after Freezing during the Lyophilization of Platelets

Pre-freezing is an important stage in freeze-drying processes.For the lyophilization of a cell,freezing not only plays a role for primary dehydration,but it also determines the amount of residual(intracellular or extracellular)water,which in turn can influence the solution properties and the choice of operation parameters.The freezing of human platelets in lyoprotectant solution is theoretically investigated here.A two-parameter model and an Arrhenius expression are used to describe cell membrane permeability and its temperature dependency.It is assumed that the intracellular solution is composed of four components:sodium chloride,trehalose,serum protein and water,while the extracellular solution consists of three components.Non-ideal solution behaviors are predicted using measured data.The concentration of maximally freeze-concentrated solution is estimated on the basis of an assumption of solute hydration.The impacts of lyoprotectant composition and extracellular sub-cooling on intracellular supercooling and residual water content in the cell are analyzed.The values of activation energy of hydraulic permeability at low temperatures are tested to study their impact on the critical cooling rate.As the mass fraction extracellular lyoprotectant(trehalose+bovineserum albumin)increases from 5 wt%to 20 wt%,the intracellular water content at the end of freezing does not change,but the intracellular solution undergoes much higher super-cooling degree.Increasing the mass ratio of trehalose to bovine serum albumin does not change the intracellular water content,but can mitigate intracellular super-cooling.While 0.05 mol/kg trehalose is loaded into platelet,the total quantity of residual water at the end of freezing may raise by 4.93%.The inclusion of dimethyl sulfoxide(Me2SO)in protectant may bring negative impacts to the drying stage by increasing the residual water content and lowering the drying temperature.

Lyophilization of pharmaceutical products:From concept to reality

Freeze-drying or lyophilization is a multi-stage operation of effectively drying a material while preserving its biological properties.The material is subject to being frozen and sublimated under vacuum upon heating.Lyophillized products are more stable,easily transported and quickly reconstituted.A benefit of low-temperature operation envisages its applications in pharmaceuticals for heat-sensitive components including vaccine and biological products.To date,analyses of the freeze-drying process have been changed from physical aspects of freezing and sublimation to a more sophisticated examination of the effects of the process on the chemical structures and the biological properties of the products themselves[1].

<i>In Vivo</i>Pharmacokinetic and Hemocompatible Evaluation of Lyophilization Induced Nifedipine Solid-Lipid Nanoparticle

Nifedipine-solid-lipid nanoparticles lyophilized with trehalose (NI-SLN-Tre) were prepared by the high pressure homogenization of a roll mixture consisting of NI and hydrogenated soybean phosphatidylcholine and dipalmitoylphosphatidylglycerol, and in vivo pharmacokinetic properties and their hemocompatibility were determined and compared with those of a NI-SLN suspension. The resulting pharmacokinetic data demonstrated that although no significant differences were observed between the time of peak concentration (Tmax), peak plasma concentration (Cmax), and the area under the curve (AUC0→∞) values of both administrated samples, NI tended to be absorbed to a much greater extent from the lyophilized NI-SLN-Tre suspensions because of the enhanced solvation of NI-SLN in gastrointestinal fluid, derived from formation of hydrogen bonds between the polar head groups of the lipids and the O-H groups of trehalose. Furthermore, the results of a hemolysis assay revealed that the NI-SLN and NI-SLN-Tre suspensions showed good hemocompatibility properties with hemolysis values of less than 5%. Taken together, the results of this study demonstrate that NI-SLN-Tre exhibits suitable pharmacokinetic properties and good biocompatibility.

Development of Fast Dissolving Tablets Containing Fexofenadine Hydrochloride Prepared by Lyophilization Technique

Objectives: To improve the aqueous solubility and dissolution of fexofenadine HCl, an attempt was made to prepare its fast dissolving tablets by lyophilization technique. Methods: For the preparation of lyophilized tablets (F1-F32), the drug was dispersed in a hydrated solution of water-soluble polymers (gelatin/maltodextrin/acacia) containing glycine and mannitol. The blend was pelted down into the patches of a blister pack, frozen down and then lyophilized. Different characterization parameters viz. differential scanning calorimetry, hardness, weight variation, X-ray diffraction (XRD), scanning electron microscopy (SEM), mercury porosimetry, solubility, wetting time and water absorption ratio, lyophilization tablet index, drug content, in vitro dissolution and stability were evaluated. Key findings: Tablets (F32) containing acacia were found to have fast disintegration and relatively higher mechanical strength with improved drug solubility. X-ray diffractogram and scanning electron micrograph indicated decrease in crystallinity of drug and a good porous structure property for prepared tablet, respectively. Dissolution study showed complete drug released within 5 min. Moreover, tablets (F32) were found to be stable for one month at 25 ± 2 °C/60 ± 5% relative humidity.

Quality by Design: Impact of Product Variables and Their Interaction on the Particle Size in Lyophilization of Sodium Fluoride

The aim of present study was to use QbD approaches to evaluate the effect of independent product variables and their interaction on particle size of sodium fluoride and then obtain the optimized experimental condition for predefined particle size of sodium fluoride. The sodium fluoride is mainly used in dental preparation for delivering the fluoride ion to the tooth enamel for that nano-particle size is required. Nowadays the milling process is used to reduce the particle size. But that process has some limitations due to crystalline nature of sodium fluoride;for overcoming those limitations, lyophilization method is used. A 43 level full factorial design was used to study the significant influence of process and product variables i.e. 1) Concentration of sodium fluoride, 2) Concentration of PVP, 3) Sample volume, 4) Drying surface, on particle size of sodium fluoride. The experimental design result shows that independent product variables significantly modify the structure and improve particle size reduction of sodium fluoride.

Lyophilized recombinant human brain natriuretic peptide for chronic heart failure:Effects on cardiac function and inflammation

BACKGROUND Chronic heart failure(CHF)is a serious and prevalent condition characterized by impaired cardiac function and inflammation.Standard therapy for CHF has limitations,prompting the exploration of alternative treatments.Recombinant human brain natriuretic peptide(BNP)has emerged as a potential therapy,with evidence suggesting that it can improve cardiac function and reduce inflammation in patients with CHF.However,further research is required to determine the efficacy and safety of lyophilized recombinant human BNP in CHF patients and its impact on microinflammatory status.This study aimed to investigate the effects of lyophilized recombinant human BNP therapy on CHF patients’cardiac function and microinflammatory status.AIM To investigate the effects of freeze-dried recombinant human BNP therapy on cardiac function and microinflammatory status in patients with CHF.METHODS In total,102 CHF patients admitted to our hospital from January 2021 to January 2022 were randomly assigned to control and observation groups(n=51 patients/group).The control patients were treated with standard HF therapy for 3 d,whereas the observational patients were injected with the recombinant human BNP for 3 d.Clinical efficacy,inflammatory factor levels,myocardial damage,cardiac function before and after the treatment,and adverse reactions during treatment were compared between the two groups.RESULTS The overall clinical efficacy was higher in the observation group than in the control group.Compared with baseline,serum hypersensitive C-reactive protein,N-terminal proBNP,and troponin I level,and physical,emotional,social,and economic scores were lower in both groups after treatment,with greater reductions in levels and scores noted in the observation group than in the control group.The overall incidence of adverse reactions in the observation group was not significantly different compared with that in the control group(P>0.05).CONCLUSION Freeze-dried recombinant human BNP therapy can improve heart function and enhance microinflammatory status,thereby improving overall quality of life without any obvious side effects.This therapy is safe and reliable.

Structure-Thermal Conductivity Tentative Correlation for Hybrid Aerogels Based on Nanofibrillated Cellulose-Mesoporous Silica Nanocomposite

Hybrid aerogels have been prepared by freeze-drying technique after mixing water dispersions of cellulose microfibers or cellulose nanofibers and silica(SiO2)of type SBA-15(2D-hexagonal).The prepared composites were characterized by different analysis techniques such as SEM,hot-filament,DMA,etc.These composites are compared to those previously prepared using nanozeolites(NZs)as mineral charge.The morphology studied by SEM indicated that both systems have different structures,i.e.,individual fibers for cellulose microfibers WP-based aerogels and films for nanofibrillated cellulose NFC-based ones....These differences seem to be driven by the charge of the particles,their aspect ratio and concentrations.These hybrid materials exhibit tunable thermal conductivity and mechanical properties.The thermal conductivity values range between^18 to 28 mW.m^-1.K^-1 and confirm the superinsulation ability of these fibrous aerogels.Synergism on the thermal insulation properties and mechanical properties was shown by adjunction of mineral particles to both cellulose-based aerogels by reaching pore size lower than 100 nm.It significantly reduces the thermal conductivity of the hybrid aerogels as predicted by Knudsen et al.Furthermore,the addition of mineral fillers to aerogels based on cellulose microfibers induced a significant increase in stiffness.

Preparation and Characterization of Low Density Poly(Imino Imino Ketone)Foam

Poly（Imino Ketone） （PIK） is a group of novel high performance polymer material with excellent thermal properties and dissolubility. Aiming at the requirements of inertial confined fusion （ICF） studies on low density polymer foams, we firstly synthesized poly（imino imino ketone） （PIIK） by palladium catalyzed C-N cross-coupling reaction, and successfully prepared the PIIK foam material with a density of 80-300 mg/cm3 by using PIIK as the raw material with thermal-induced phase separation and lyophilization technique. Mercury injection method was used to determine the structure of PIIK foams, and the results indicated that the mean pore diameter was lower than 5 ~tm and it had relatively high voidage and specific surface area.

Extending the Shelf-Life of <i>Myrothecium verrucaria</i>, a Bioherbicide

The shelf-life of a bioherbicide product is an important factor with regard to its commercial potential. The bioherbicidal efficacy of freshly fermented Myrothecium verrucaria (strain IMI 368023) (MV) mycelia formulations and MV mycelia preparations that had been freeze-dried and then stored at -20&deg;C for 8 years was compared. Two concentrations of each formulation (1.0x and 0.5x) were tested, utilizing bioassays on seedlings of the weed, hemp sesbania (Sesbania exaltata) under greenhouse conditions or in darkness utilizing hydroponically grown seedlings. Freeze drying of freshly prepared MV mycelium produced a light, brownish-colored powder. Efficacy tests of this reconstituted 8-year-old dried material showed that some bioherbicidal activity was lost during long-term storage, i.e., ~20% and ~60% seedling dry weight reduction at the 1.0x and 0.5x rate, respectively. Although plant mortality was greater in the fresh mycelial preparations treatments versus the freeze-dried and stored samples at all time points in the time-course, the stored material still caused >80% mortality, 15 days after treatment. Comparative disease progression ratings also showed a similar trend. Overall results show that freeze-drying MV is a useful method to reduce the bulk and cumbersomeness of storing heavy liquid fermentation product, while retaining bioherbicidal activity. These findings increase the utility of this bioherbicide and offer the potential to use the dried material in soil treatments or in a more concentrated form than attainable via the fermented product.

Clinical Non-inferiority Trial on Treatment of Coronary Heart Disease Angina Pectoris of Xin-blood Stasis Syndrome Type with Lyophilized Salvia Salt of Lithospermic Acid Powder for Injection

Objective： To evaluate the effectiveness and safety of lyophilized Salvia salt of lithospermic acid powder for injection （SSLA） in treating coronary heart diseases angina pectoris （CHD-AP） of Xin-blood stasis syndrome type, and to conduct the non-inferiority trial with Danshen injection （丹参注射液, DSI） as positive control. Methods： An non-inferiority clinical layered, segmented, randomized, and blinded trial on three parallel and multiple centered groups was conducted in 480 patients with stable effort angina grade Ⅰ , Ⅱand Ⅲ, who had two or more times of attack every week. The 240 patients in test group A were treated with SSLA 200 mg added in 250 ml of 5% glucose solution for intravenous dripping every day; the 120 patients in test group B were treated with SSLA but the dosage doubled; and the 120 patients in the control group were treated with DSI 20 ml daily in the same method as SSLA was given. The clinical effectiveness and safety were evaluated after the patients were treated for 14 days. Results： The results showed that the markedly effective rate in test groups A, B and control group was 37.45 %, 36.75 % and 30.09 % respectively, while the total effective rate in them was 88.09%, 89.74% and 67.26% respectively. Statistical significance was shown in comparisons of the therapeutic effect between control group with test group A and test group B, with that in the two test groups superior to that in the control group, and non-inferiority trial showed eligibility （P〈0.01）. Adverse reaction appeared in 8 patients in the test groups and 2 in the control group. Conclusion： SSLA has definite therapeutic effect in treating patients with CHD-AP, with its effect not inferior to that of DSI, and no evident toxic-adverse reaction.

Immunogenicity of Lyophilized MVA Vaccine for HIV-1 in Mice Model

Highly attenuated modified vaccinia Ankara（MVA） is sensitive to repeat freeze-thaw cycle and easy to lose activity. In order to make the activity of MVA vaccine remain stable during its manufacturing, storage, and administration, the lyophilization as a good option could be resorted to; through screening, the right stabilizer composition and its production procedure were obtained. The final moisture content of freezing-dried recombinant MVA-HIV vaccine was lower than 3%. It can be reconstituted quickly and shows regular physical appearance and stable potency. In vivo functional experiment, mice were divided randomly into the liquid vaccination group, the lyophilized vaccination group, and the control group. Having been DNA vaccine priming, the mice were boosted with a dose of 10^7 pfu MVA- HIV vaccine, which produced indistinguishable antibody titer and cytotoxic T-lymphocyte（CTL） level compared with those of liquid vaccination group （ P 〉 0.05 ）. These results demonstrate that lyophilized MVA vaccine can induce high immunogenicity in mice.

Reconstruction of Rabbit Corneal Layer Composed of Corneal Fibroblasts and Corneal Epithelium on the Lyophilized Amniotic Membrane

Many researchers have employed the cryopreserved amniotic membrane（CAM） and corneal epithelial cells in the treatment of a severely damaged burned cornea, with corneal epithelial cells cultured on an amniotic membrane （AM）. The lyophilized amniotic membrane（LAM） has a higher graft take and a longer shelf life; it is easier to store and safer because of gamma irradiation. Two Teflon rings（ Ahn＇s supporter） were made for culturing the cells on the LAM, and were then used to support the LAM. To reconstruct a corneal layer composed of corneal fibroblasts and epithelium, the corneal fibroblasts were first cultivated on the stromal side of LAM for five days, foUowed by epithelial cells culture on the epithelial side, by using the air-liquid interface culture. The reconstructed corneal layer composed of corneal fibroblasts and corneal epithelial cells has a much healthier basal layer of corneal epithelium than the reconstructed corneal epithelium, which was got by using only corneal epithelial cells, and resembles the epithelium of normal corneas, without the horny layer. Thus, the reconstruction of the corneal layer by using a LAM is considered to be a good in vitro model, not only for its application in toxicological test kits, but also for transplantation in patients with a severely damaged cornea.

In Vitro Study on the Repair Effect of Fibronectin Lyophilized Powder

Fibronectin has a good repair effect on skin,but its practical application is limited by its easy degradation and difficult preservation.Freeze-drying technology can extend the shelf life of biological products,but may cause damage to some of their biological activities.Therefore,it is necessary to conduct comprehensive and scientific testing of fibronectin lyophilized powder prepared by freeze-drying technology to evaluate its actual efficacy.In this study,by means of in vitro cell experiment,zebrafish animal model experiment and the experiment on the human skin,the safety of fibronectin lyophilized powder prepared by the new formula and the actual efficacy of skin repair were preliminarily and multidimensionally evaluated,so as to provide reference and basis for further research,human clinical trial and application.The results showed that fibronectin lyophilized powder prepared by the new formula had low cytotoxicity,significant ability of promoting cell migration and proliferation,and had stronger skin repair effect.The new Fibronectin lyophilized powder has the characteristics of good safety and strong skin repair effect,which shows that it has good development prospects.These results provide a new strategy for the development of skin repair products.

Network Pharmacology-Based Dissection of the Bioactive Compounds and Pharmacological Mechanisms of Yiqi Fumai Lyophilized Injection for the Treatment of Heart Failure

Objective:Yiqi Fumai Lyophilized Injection(YQFM),a Chinese medicine injection,has been widely used for the treatment of cardiovascular diseases,especially heart failure(HF).However,bioactive compounds and underlying mechanisms of YQFM in treating HF remain poorly understood.Materials and Methods:Network pharmacology was employed to investigate the bioactive compounds and mechanisms of YQFM.A compound-target network was constructed to screen bioactive compounds based on contribution index calculation.Then,an adriamycin-induced HF rat model was established to evaluate the cardio-protective effects of YQFM by hematoxylin and eosin staining and enzyme-linked immunosorbent assays.Results:Network pharmacology indicated that YQFM may alleviate HF through 36 compounds and 109 targets.Particularly,ginsenosides Rb1,Rg1,Re,Rf,Rb2,Rh1,schisandrin,and ginsenoside Rc were indicated as the top contributors of YQFM in treating HF.YQFM was predicted to act on multiple targets such as vascular endothelial growth factor A,interleukin-2(IL-2),IL-6,and IL-1β,as well as to regulate signaling pathways such as hypoxia-inducible factor 1,tumor necrosis factor,VEGF,and PI3K-Akt.The pharmacological study suggested that YQFM could attenuate cardiac injury and up-regulate plasma concentrations of VEGFR-1 and NO in HF rats.Ginsenoside Rb1,as the major contributor from network pharmacology analysis,also showed a cardioprotective effect and up-regulation of VEGFR-1 in plasma.Conclusions:Ginsenosides and schisandrin were predicted as the most important contributors to the cardioprotective effect of YQMF.Ginsenoside Rb1 was proved to alleviate HF and increase the plasma concentration of VEGFR-1.

Preparation of slow-release regulated Rs-198 bilayer microcapsules and application of its lyophilized bacterial inoculant on Capsicum annuum L.under salt stress

The survival adaptation of bacteria in saline soil is poor.The bilayer microcapsules were prepared by secondary embedding of monolayer sodium alginate(NaAlg)-bentonite(Bent)-sodium carboxy-methylcellulose(CMC)microcapsules wrapped with plant growth promoting rhizobacteria(PGPR)Pseudomonas putida Rs-198 by chitosan solution to promote the synergistic effect of bilayer microen-capsulation and PGPR.The characterization of the Rs-198 bilayer microcapsules showed that the amino and carboxyl groups were cross-linked and a thin layer of chitosan was formed on the outside of the microcapsule.The bilayer microcapsule(Ch-d)with a chitosan concentration of 0.8 wt%and pH 6 showed a slow release of bacteria with a maximum release of 6.06 × 10^(9) cfu/g on the 7th day.The viable bacteria of Ch-d increased by 4.42%after 60 days of storage compared with monolayer microcapsules.The 0.9 wt%L-cysteine,10 wt%glycerinum,10 wt%trehalose and 12 wt%soluble starch were added as bacterial protective agents during the process of preparing the Ch-d lyophilized bacterial inoculant(Ch-d LBI).Pot experiments showed that Ch-d LBI exhibited better growth promotion of Capsicum annuum L.under salt stress.Therefore,the bilayer microcapsule as slow-release bacterial inoculant is a potential alternative for sustainable agriculture.

Changes on membrane integrity and ultrastructure of human sperm after freeze-drying

Objective To observe changes on membrane integrity and ultrastructure of human sperm after freeze-drying.Methods Semen samples from both normospermic donors（group A, n=15） and infertile men with abnormal sperm parameters（group B, n=15） were enrolled into this study. These samples were freeze-dried by using a freeze-drying method. The membrane integrity in the head and tail regions of individual spermatozoon was examined by using the combined hypo-osmotic swelling-eosin Y exclusion test. Sperm ultrastructure in groups A（n=3） and B（n=3） was observed by scanning electron microscopy（SEM）.Results After freeze-drying, all spermatozoa were types I（damaged both head and tail membranes） and III（damaged head membrane and intact tail membrane） membrane integrity in groups A and B. Type III of group B had lower value than that of group A（P〈0.01）. Under SEM, intact freeze-dried spermatozoa including abnormal morphology and normal-looking morphology were observed in both groups A and B. A few freezedried sperm heads had unsmooth or fuzzy surface. Isolated sperm heads, bent tails,broken sperm tails or fragmentary tails were more frequently seen in group B than those in group A.Conclusion Freeze-dried human spermatozoa could have intact structural components. However, freeze-drying resulted in severe damage on membrane integrity and ultrastructure of sperm. Samples from infertile men would have less resistance to freeze-drying.

Facile preparation of unique three-dimensional(3D)α-MnCh/MWCNTs macroporous hybrid as the high-performance cathode of rechargeable Li-O2 batteries

Un doubtedly,there remai ns an urge nt prerequisite to achieve sign ifica nt adva nces in both the specific capacity and cyclability of Li-O2 batteries for their practical application.In this work,a series of unique three-dimensional(3D)α-MnO2/MWCNTs hybrids are successfully prepared using a facile lyophilization method and investigated as the cathode of Li-O2 batteries.Thereinto,cross-1 inkedα-MnO2/MWCNTs nano composites are first syn thesized via a modified chemical route.Results dem on strate that MnO2 nano rods in the nano composites have a length of 100-400 nm and a diameter ranging from 5 to 10 nm,and more attractively,the as-lyophilized 3D MnO2/MWCNTs hybrids is uniquely constructed with large amounts of interconnected macroporous channels.The U-O2 battery with the 3D macroporous hybrid cathode that has a mass percentage of 50%ofα-MnO2 delivers a high discharge specific capacity of 8,643 mAh·g^-1 at 100 mA·g^-1,and main tains over 90 cycles before the discharge voltage drops to 2.0 V un der a controlled specific capacity of 1,000 mAh·g^-1.It is observed that when being recharged,the product of toroidal Li2O2 particles disappears and electrode surfaces are well recovered,thus confirming a good reversibility.The excellent performanee of Li-O2 battery with the 3Dα-MnO2/MWCNTs macroporous hybrid cathode is ascribed to a syn ergistic com bination betwee n the unique macroporous architecture and highly efficient bi-fun ctionalα-MnO2/MWCNTs electrocatalyst.

Preservation of nucleic acids by freeze-drying for next generation sequencing analyses of soil microbial communities

Aims Soil sample preservation is a challenging aspect in molecular studies on soil microbial communities.The demands for specialized sample storage equipment,chemicals and standardized protocols for nucleic acid extraction often require sample processing in a home laboratory that can be continents apart from sampling sites.Standard sampling procedures,especially when dealing with RNA,comprise immediate snap freezing of soils in liquid nitrogen and storage at−80℃until further processing.For these instances,organizing a reliable cooling chain to transport hundreds of soil samples between continents is very costly,if possible at all.In this study we tested the effect of soil sample preservation by freeze-drying with subsequent short-term storage at 4℃or ambient temperatures compared to−80℃freezing by comparative barcoding analyses of soil microbial communities.Methods Two grassland soil samples were collected in Central Germany in the Biodiversity Exploratory Hainich-Dün.Samples were freeze-dried or stored at−80℃as controls.Freeze-dried samples were stored at 4℃or ambient temperature.Investigated storage times for both storage temperatures were 1 and 7 days.Total DNA and RNA were extracted and bacterial and arbuscular mycorrhizal(AM)fungal communities were analyzed by amplicon 454 pyrosequencing of the 16S(V4-V5 variable region)and 18S(NS31-AM1 fragment)of ribosomal RNA(rRNA)marker genes,respectively.Important Findings Bacterial communities were sufficiently well preserved at the rDNA and rRNA level although storage effects showed as slightly decreased alpha diversity indices for the prolonged storage of freeze-dried samples for 7 days.AM fungal communities could be studied without significant changes at the rDNA and rRNA level.Our results suggest that proper sampling design followed by immediate freeze-drying of soil samples enables short-term transportation of soil samples across continents.