Pharmacokinetic Evaluation of Improved Oral Bioavailability of Valsartan: Proliposomes <Emphasis Type="Italic">Versus</Emphasis> Self-Nanoemulsifying Drug Delivery System

The objective of this study was to develop proliposomes and self-nanoemulsifying drug delivery system (SNEDDS) for a poorly bioavailable drug, valsartan, and to compare their in vivo pharmacokinetics. Proliposomes were prepared by thin-film hydration method using different lipids such as soy phosphatidylcholine (SPC), hydrogenated soy phosphatidylcholine (HSPC), distearyl phosphatidylcholine (DSPC), dimyristoylphosphatidylcholine (DMPC), and dimyristoyl phosphatidylglycerol sodium (DMPG) and cholesterol in various ratios. SNEDDS formulations were prepared using varying concentrations of capmul MCM, labrafil M 2125, and Tween 80. Both proliposomes and SNEDDS were evaluated for particle size, zeta potential, in vitro drug release, in vitro permeability, and in vivo pharmacokinetics. In vitro drug release was carried out in purified water and 0.1 N HCl using USP type II dissolution apparatus. In vitro drug permeation was studied using parallel artificial membrane permeation assay (PAMPA) and everted rat intestinal permeation techniques. Among the formulations, the proliposomes with drug/DMPG/cholesterol in the ratio of 1:1:0.5 and SNEDDS with capmul MCM (16.0% w/w), labrafil M 2125 (64.0% w/w), and Tween 80 (18.0% w/w) showed the desired particle size and zeta potential. Enhanced drug release was observed with proliposomes and SNEDDS as compared to pure valsartan. Valsartan permeability across PAMPA and everted rat intestinal permeation models was significantly higher with proliposomes and SNEDDS. Following single oral administration of proliposomes and SNEDDS, a relative bioavailability of 202.36 and 196.87%, respectively, was achieved compared to pure valsartan suspension. The study results indicated that both proliposomes and SNEDDS formulations are comparable in improving the oral bioavailability of valsartan.     

Development of Microemulsions and Microemulgels for Enhancing Transdermal Delivery of <Emphasis Type="Italic">Kaempferia parviflora</Emphasis> Extract

The purpose of this research was to develop microemulsions (ME) and microemulgels (MG) for enhancing transdermal delivery of Kaempferia parviflora (KP) extract. The methoxyflavones were used as markers. Various formulations of ME and MG containing 10% w/v KP extract were prepared, and the in vitro skin permeation and deposition were investigated. The potential ME system containing oleic acid (5% w/v), Tween 20 (20% w/v), PG (40% w/v), and water (35% w/v) was successfully formulated. ME with 10% w/v limonene (ME-L10%) showed higher methoxyflavones flux than ME-L5%, ME-L1%, ME without limonene, and KP extract in water, respectively. ME-L10% was selected for adding a gelling agent to form microemulgels (MG-L10%). However, the high viscosity of the gel formulation might control the diffusion of the compound from gel layer into the skin. Therefore, the liquid formulation provided potential ME droplets to deliver KP extract through the skin. Limonene also plays an effective role on the skin permeation, in which the histological image of the skin treated with ME-L10% exhibited larger space of each flattened keratinocyte layer in the stratum corneum compared to the skin treated with KP extract in water. Moreover, ME-L10% showed good stability. Therefore, ME-L10% was a potential formulation for improving transdermal delivery of KP extract.     

Strain-specific response to ampicillin in <Emphasis Type="Italic">Wolbachia-</Emphasis>infected mosquito cell lines

Wolbachia pipientis (Rickettsiales; Anaplasmataceae) is an obligate intracellular alpha proteobacterium that occurs in arthropods and filarial worms. Some strains of Wolbachia can be maintained as persistent infections in insect cell lines. C/wStr1 cells from the mosquito Aedes albopictus maintain a robust infection with Wolbachia strain wStr, originally isolated from the planthopper, Laodelphax striatellus. To explore possible functions of penicillin-binding proteins expressed from the wStr genome, C/wStr1 cells were exposed to ampicillin. Absolute levels of Wolbachia increased 3.5-fold in ampicillin-treated cells and fivefold in naive cells newly infected with wStr. Because cell numbers were depressed by ampicillin treatment, Wolbachia yield on a per-cell basis increased by 15-fold. The absence of a similar effect on wAlbB in Aa23 host cells suggests that the Wolbachia strain, the presence/absence of genes encoding penicillin-binding proteins, or the interaction between wAlbB and its host cells may modulate the effects of ampicillin.     

Preparation and Optimization of Fast-Disintegrating Tablet Containing Naratriptan Hydrochloride Using D-Optimal Mixture Design

Optimization of a lyophilized fast-disintegrating tablet (LFDT) formulation containing naratriptan hydrochloride, an antimigraine drug, was the foremost objective of the study, aiming in achieving fast headache pain relief. The Design-Expert® v10 software was used to generate formulations using D-optimal mixture design with four components: gelatin (X₁), hydrolyzed gelatin (X₂), glycine (X₃), and mannitol (X₄) of total solid material (TSM) w/w. The effect of the relative proportion of each component was determined on friability (Y₁), hardness (Y₂), and in vitro disintegration time (Y₃), which was then applied for formulation optimization. In addition, their effect on tablet porosity was determined via scanning electron microscopy (SEM). Drug-excipient interaction was evaluated using differential scanning calorimetry (DSC). A comparative dissolution study against the conventional tablets was studied. Accelerated stability study was carried out in (Al/Al) and (Al/PVC) blister packs. An in vivo pharmacokinetic study was carried out to compare the optimized formulation and the conventional tablets. The optimized formulation’s responses were 0.30%, 3.4 kg, and 6.12 s for Y₁, Y₂, and Y₃, respectively. No drug-excipient interaction was specified via DSC. The optimized formulation exhibited porous structure as determined via SEM. Dissolution study demonstrated complete dissolution within 1.5 min. Study indicated stability for 78 months in (Al/Al) blister packs. In vivo pharmacokinetic study demonstrated that C_max, AUC_last, and AUC_inf were significantly higher for the developed formulation. As well, the T_max was 1 h earlier than that of convenient tablet. An LFDT would achieve a faster onset of action for naratriptan compared to other formulations.     

Improved Skin Penetration Using <Emphasis Type="Italic">In Situ</Emphasis> Nanoparticulate Diclofenac Diethylamine in Hydrogel Systems: <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> Studies

Delivering diclofenac diethylamine transdermally by means of a hydrogel is an approach to reduce or avoid systemic toxicity of the drug while providing local action for a prolonged period. In the present investigation, a process was developed to produce nanosize particles (about 10 nm) of diclofenac diethylamine in situ during the development of hydrogel, using simple mixing technique. Hydrogel was developed with polyvinyl alcohol (PVA) (5.8% w/w) and carbopol 71G (1.5% w/w). The formulations were evaluated on the basis of field emission scanning electron microscopy, texture analysis, and the assessment of various physiochemical properties. Viscosity (163–165 cps for hydrogel containing microsize drug particles and 171–173 cps for hydrogel containing nanosize drug particles, respectively) and swelling index (varied between 0.62 and 0.68) data favor the hydrogels for satisfactory topical applications. The measured hardness of the different hydrogels was uniform indicating a uniform spreadability. Data of in vitro skin (cadaver) permeation for 10 h showed that the enhancement ratios of the flux of the formulation containing nanosize drug (without the permeation enhancer) were 9.72 and 1.30 compared to the formulation containing microsized drug and the marketed formulations, respectively. In vivo plasma level of the drug increased predominantly for the hydrogel containing nanosize drug-clusters. The study depicts a simple technique for preparing hydrogel containing nanosize diclofenac diethylamine particles in situ, which can be commercially viable. The study also shows the advantage of the experimental transdermal hydrogel with nanosize drug particles over the hydrogel with microsize drug particles.     

<Emphasis Type="Italic">Flavobacterium parvum</Emphasis> sp. nov., isolated from soil polluted by sewer water

A novel Gram-stain-negative, motile by means of gliding, and short rod-shaped bacterium, designated HS916T, was isolated from soil polluted by sewer water in Cheonan-si, South Korea. Growth occurred at 10–35°C (optimum 30°C), pH 6.0–8.0 (optimum pH 7.0), and 0–1% sodium chloride (NaCl, w/v). Based on similarities of 16S rRNA gene sequences, strain HS916^T was closely related to members of the genus Flavobacterium, exhibiting the highest sequence similarities with Flavobacterium glycines Gm-149^T (96.4%), followed by F. granuli Kw05^T (96.3%), F. fluminis 3R17^T (96.3%), F. aquicola TMd3a3^T (96.2%), and F. nitratireducens N1^T (96.2%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HS916T was placed in a monophyletic cluster with F. nitratireducens N1^T and F. fluminis 3R17^T. The predominant fatty acids (> 5% of the total) of strain HS916^T were iso-C_15:0, anteiso-C_15:0, iso-C_15:0 3-OH, C_17:1ω6с, C_16:0 3-OH, iso-C_17:0 3-OH, and summed feature 3 (C_16:1ω7с and/or C_16:1ω6с). The major polar lipids of the strain comprised phosphatidylethanolamine, unidentified aminolipids, and five unidentified lipids. The predominant respiratory quinone and the major polyamine were menaquinone-6 (MK-6) and symhomospermidine, respectively. The DNA G + C content of strain HS916^T was 34.9 mol%. Based on polyphasic analyses, strain HS916^T represents a novel species belonging to the genus Flavobacterium, for which the name Flavobacterium parvum sp. nov. is proposed. The type strain is HS916T (= KACC 19448^T = JCM 32368^T).     

Oral fast-dissolving films containing lutein nanocrystals for improved bioavailability: formulation development, <Emphasis Type="Italic">in vitro</Emphasis> and <Emphasis Type="Italic">in vivo</Emphasis> evaluation

Lutein is widely used as diet supplement for prevention of age-related macular degeneration. However, the application and efficacy of lutein in food and nutritional products has been hampered due to its poor solubility and low oral bioavailability. This study aimed to develop and evaluate the formulation of oral fast-dissolving film (OFDF) containing lutein nanocrystals for enhanced bioavailability and compliance. Lutein nanocrystals were prepared by anti-solvent precipitation method and then encapsulated into the films by solvent casting method. The formulation of OFDF was optimized by Box-Behnken Design (BBD) as follows: HPMC 2.05% (w/v), PEG 400 1.03% (w/v), Cremophor EL 0.43% (w/v). The obtained films exhibited uniform thickness of 35.64 ± 1.64 μm and drug content of 0.230 ± 0.003 mg/cm² and disintegrated rapidly in 29 ± 8 s. The nanocrystal-loaded films with reconstituted particle size of 377.9 nm showed better folding endurance and faster release rate in vitro than the conventional OFDFs with raw lutein. The microscope images, thermograms, and diffractograms indicated that lutein nanocrystals were highly dispersed into the films. After administrated to SD rats, t _max was decreased from 3 h for oral solution formulation to less than 0.8 h for OFDF formulations, and C _max increased from 150 ng/mL for solution to 350 ng/mL for conventional OFDF or 830 ng/mL for nanocrystal OFDF. The AUC _0-24h of conventional or nanocrystal OFDF was 1.37 or 2.08-fold higher than that of the oral solution, respectively. These results suggested that drug nanocrystal-loaded OFDF can be applied as a promising approach for enhanced bioavailability of poor soluble drugs like lutein.     

Locomotor synergies in fish

The kinematic characteristics {f(v), A(v), w(v)} allow a first-approximation representation of locomotor synergies in the swimming of fish: f is the frequency of the transverse oscillations, A is the amplitude of the caudal fin sweep, w is the velocity of the locomotor wave, and v is the locomotion speed. The additional compared characteristics included the step length L(v) and the wavelength λ(v), where L ≡ vT is the distance covered by the fish during the period T ≡ 1/f, and λ ≡ wT. These kinematic characteristics were derived from video recordings of swimming in six fish species. Three of the species investigated belonged to the anguilliform type, while the three others belonged to the carangiform type. The constant value of the wavelength λ at all speeds v was the common feature of the two types. The anguilliform fish performed a oneparameter version of locomotion control: the locomotion speed v changed due to the change of the wave velocity w and the undulatory amplitude remained constant. The carangioid fish used a two-parameter version of control, with changes in both the wave velocity w and the amplitude of undulations of the body and tail fin.     

Exome sequencing confirms molecular diagnoses in 38 Chinese families with hereditary spherocytosis

Hereditary spherocytosis(HS), the most common cause of congenital hemolytic anemia, is caused by deficiency of the erythrocyte membrane proteins. Five causative genes(ANK1, SPTB, SPTA1, SLC4 A1, and EPB42) have been identified. To date,molecular genetic studies have been performed in different populations, including the American, European, Brazilian, Japanese and Korean populations, whereas only a few studies have been described in the Chinese population. Here, by reanalysis of the exome data, we revealed causative mutations and established a definitive diagnosis of HS in all 38 Chinese families. We found 34 novel mutations and four reported mutations in three known HS-causing genes—17 in ANK1, 17 in SPTB and four in SLC4 A1,suggesting that ANK1 and SPTB are the major genes in Chinese patients with HS. All of the ANK1 or SPTB mutations, scattered throughout the entire genes, are non-recurrent; and most of them are null mutations, which might cause HS via a haploinsufficiency mechanism. De novo mutations in ANK1 or SPTB often occur with an unexpected high frequency(87.5% and64.2%, respectively). Our study updates our knowledge about the genetic profile of HS in Chinese and shows that family-based,especially parent-offspring trio, sequencing analysis can help to increase the diagnostic power and improve diagnostic efficiency.     

Effect of Percent Relative Humidity,Moisture Content,and Compression Force on Light-Induced Fluorescence (LIF) Response as a Process Analytical Tool

The effect of percent relative humidity (16–84% RH), moisture content (4.2–6.5% w/w MC), and compression force (4.9–44.1 kN CF) on the light-induced fluorescence (LIF) response of 10% w/w active pharmaceutical ingredient (API) compacts is reported. The fluorescent response was evaluated using two separate central composite designs of experiments. The effect of % RH and CF on the LIF signal was highly significant with an adjusted R ² ?=?0.9436 and p?<?0.0001. Percent relative humidity (p?=?0.0022), CF (p?<?0.0001), and % RH² (p?=?0.0237) were statistically significant factors affecting the LIF response. The effects of MC and CF on LIF response were also statistically significant with a p value <0.0001 and adjusted R ² value of 0.9874. The LIF response was highly impacted by MC (p?<?0.0001), CF (p?<?0.0001), and MC² (p?=?0022). At 10% w/w API, increased % RH, MC, and CF led to a nonlinear decrease in LIF response. The derived quadratic model equations explained more than 94% of the data. Awareness of these effects on LIF response is critical when implementing LIF as a process analytical tool.     

Colon-Targeted Delivery of IgY Against <Emphasis Type="Italic">Clostridium difficile</Emphasis> Toxin A and B by Encapsulation in Chitosan-Ca Pectinate Microbeads

This study investigated the use of a newly developed chitosan-Ca pectinate microbead formulation for the colon-targeted delivery of anti-A/B toxin immunoglobulin of egg yolk (IgY) to inhibit toxin binding to colon mucosa cells. The effect of the three components (pectinate, calcium chloride, and chitosan) used for the microbead production was examined with the aim of identifying the optimal levels to improve drug encapsulation efficiency, swelling ratio, and cumulative IgY release rate. The optimized IgY-loaded bead component was pectin 5% (w/v), CaCl₂ 3% (w/v), and chitosan 0.5% (w/v). Formulated beads were spherical with 1.2-mm diameter, and the drug loading was 45%. An in vitro release study revealed that chitosan-Ca pectinate microbeads inhibited IgY release in the upper gastrointestinal tract and significantly improved the site-specific release of IgY in the colon. An in vivo rat study demonstrated that 72.6% of biologically active IgY was released specifically in the colon. These results demonstrated that anti-A/B toxin IgY-loaded chitosan-Ca pectinate oral microbeads improved IgY release behavior in vivo, which could be used as an effective oral delivery platform for the biological treatment of Clostridium difficile infection (CDI).     

The Plant Alkaloid Camptothecin as a Novel Antifouling Compound for Marine Paints: Laboratory Bioassays and Field Trials

The extensive use of copper and booster biocides in antifouling (AF) paints has raised environmental concerns and the need to develop new AF agents. In the present study, 18 alkaloids derived from terrestrial plants were initially evaluated for AF activity using laboratory bioassays with the bryozoan Bugula neritina and the barnacle Balanus albicostatus. The results showed that 4 of the 18 alkaloids were effective in inhibiting larval settlement of B. neritina, with an EC₅₀ range of 6.18 to 43.11 μM, and 15 of the 18 alkaloids inhibited larval settlement of B. albicostatus, with EC₅₀ values ranging from 1.18 to 67.58 μM. Field trials that incorporated five alkaloids respectively into paints with 20% w/w indicated an in situ AF efficiency of evodiamine, strychnine, camptothecin (CPT), and cepharanthine, with the most potent compound being CPT, which also exhibited stronger AF efficiency than the commercial antifoulants cuprous oxide and zinc pyrithione in the field over a period of 12 months. Further field trials with different CPT concentrations (0.1 to 20% w/w) in the paints suggested a concentration-dependent AF performance in the natural environment, and the effective concentrations to significantly inhibit settlement of biofoulers in the field were ≥?0.5% w/w (the efficiency of 0.5% w/w lasted for 2 months). Moreover, CPT toxicity against the crustacean Artemia salina, the planktonic microalgae Phaeodactylum tricornutum and Isochrysis galbana, was examined. The results showed that 24 h LC₅₀ of CPT against A. salina was 20.75 μM, and 96 h EC₅₀ (growth inhibition) values of CPT to P. tricornutum and I. galbana were 55.81 and 6.29 μM, respectively, indicating that CPT was comparatively less toxic than several commercial antifoulants previously reported. Our results suggest the novel potential application of CPT as an antifoulant.     

Development,Optimization, and Evaluation of Carvedilol-Loaded Solid Lipid Nanoparticles for Intranasal Drug Delivery

Carvedilol, a beta-adrenergic blocker, suffers from poor systemic availability (25%) due to first-pass metabolism. The aim of this work was to improve carvedilol bioavailability through developing carvedilol-loaded solid lipid nanoparticles (SLNs) for nasal administration. SLNs were prepared by emulsion/solvent evaporation method. A 2³ factorial design was employed with lipid type (Compritol or Precirol), surfactant (1 or 2% w/v poloxamer 188), and co-surfactant (0.25 or 0.5% w/v lecithin) concentrations as independent variables, while entrapment efficiency (EE%), particle size, and amount of carvedilol permeated/unit area in 24 h (Q ₂₄) were the dependent variables. Regression analysis was performed to identify the optimum formulation conditions. The in vivo behavior was evaluated in rabbits comparing the bioavailability of carvedilol after intravenous, nasal, and oral administration. The results revealed high drug EE% ranging from 68 to 87.62%. Carvedilol-loaded SLNs showed a spherical shape with an enriched core drug loading pattern having a particle size in the range of 66 to 352 nm. The developed SLNs exhibited significant high amounts of carvedilol permeated through the nasal mucosa as confirmed by confocal laser scanning microscopy. The in vivo pharmacokinetic study revealed that the absolute bioavailability of the optimized intranasal SLNs (50.63%) was significantly higher than oral carvedilol formulation (24.11%). Hence, we conclude that our developed SLNs represent a promising carrier for the nasal delivery of carvedilol.     

Bacterial metabolites from intra- and inter-species influencing thermotolerance: the case of <Emphasis Type="Italic">Bacillus cereus</Emphasis> and <Emphasis Type="Italic">Geobacillus stearothermophilus</Emphasis>

Bacterial metabolites with communicative functions could provide protection against stress conditions to members of the same species. Yet, information remains limited about protection provided by metabolites in Bacillus cereus and inter-species. This study investigated the effect of extracellular compounds derived from heat shocked (HS) and non-HS cultures of B. cereus and Geobacillus stearothermophilus on the thermotolerance of non-HS vegetative and sporulating B. cereus. Cultures of B. cereus and G. stearothermophilus were subjected to HS (42 or 65 °C respectively for 30 min) or non-HS treatments. Cells and supernatants were separated, mixed in a combined array, and then exposed to 50 °C for 60 min and viable cells determined. For spores, D values (85 and 95 °C) were evaluated after 120 h. In most cases, supernatants from HS B. cereus cultures added to non-HS B. cereus cells caused their thermotolerance to increase (D ₅₀ 12.2–51.9) when compared to supernatants from non-HS cultures (D ₅₀ 7.4–21.7). While the addition of supernatants from HS and non-HS G. stearothermophilus cultures caused the thermotolerance of non-HS cells from B. cereus to decrease initially (D ₅₀ 3.7–7.1), a subsequent increase was detected in most cases (D ₅₀ 18–97.7). In most cases, supernatants from sporulating G. stearothermophilus added to sporulating cells of B. cereus caused the thermotolerance of B. cereus 4810 spores to decline, whereas that of B. cereus 14579 increased. This study clearly shows that metabolites in supernatants from either the same or different species (such as G. stearothermophilus) influence the thermotolerance of B. cereus.     

Thermosensitive Poloxamer 407/Poly(Acrylic Acid) Hydrogels with Potential Application as Injectable Drug Delivery System

Thermosensitive hydrogels are of great interest for in situ gelling drug delivery. The thermosensitive vehicle with a gelation temperature in a range of 30–36°C would be convenient to be injected as liquid and transform into gel after injection. To prepare novel hydrogels gelling near body temperature, the gelation temperature of poloxamer 407 (PX) were tailored by mixing PX with poly(acrylic acid) (PAA). The gelation behaviors of PX/PAA systems as well as the interaction mechanism were investigated by tube inversion, viscoelastic, shear viscosity, DSC, SEM, and FTIR studies. The gelation temperature of the plain PX solutions at high concentration of 18, 20, and 22% (w/w) gelled at temperature below 28°C, which is out of the suitable temperature range. Mixing PX with PAA to obtain 18 and 20% (w/w) PX with 1% (w/w) PAA increased the gelation temperature to the desired temperature range of 30–36°C. The intermolecular entanglements and hydrogen bonds between PX and PAA may be responsible for the modulation of the gelation features of PX. The mixtures behaved low viscosity liquid at room temperature with shear thinning behavior enabling their injectability and rapidly gelled at body temperature. The gel strength increased, while the pore size decreased with increasing PX concentration. Metronidazole, an antibiotic used for periodontitis, was incorporated into the matrices, and the drug did not hinder their gelling ability. The gels showed the sustained drug release characteristic. The thermosensitive PX/PAA hydrogel could be a promising injectable in situ gelling system for periodontal drug delivery.     

Formulation and <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> Evaluation of Lipid-Based Terbutaline Sulphate Bi-layer Tablets for Once-Daily Administration

The objective of this study was to prepare and evaluate terbutaline sulphate (TBS) bi-layer tablets for once-daily administration. The bi-layer tablets consisted of an immediate-release layer and a sustained-release layer containing 5 and 10 mg TBS, respectively. The sustained-release layer was developed by using Compritol®888 ATO, Precirol® ATO 5, stearic acid, and tristearin, separately, as slowly eroding lipid matrices. A full 4?×?2² factorial design was employed for optimization of the sustained-release layer and to explore the effect of lipid type (X ₁), drug–lipid ratio (X ₂), and filler type (X ₃) on the percentage drug released at 8, 12, and 24 h (Y ₁, Y ₂, and Y ₃) as dependent variables. Sixteen TBS sustained-release matrices (F1–F16) were prepared by melt solid dispersion method. None of the prepared matrices achieved the targeted release profile. However, F2 that showed a relatively promising drug release was subjected to trial and error optimization for the filler composition to develop two optimized matrices (F17 and F18). F18 which consisted of drug–Compritol®888 ATO at ratio (1:6 w/w) and Avicel PH 101/dibasic calcium phosphate mixture of 2:1 (w/w) was selected as sustained-release layer. TBS bi-layer tablets were evaluated for their physical properties, in vitro drug release, effect of storage on drug content, and in vivo performance in rabbits. The bi-layer tablets showed acceptable physical properties and release characteristics. In vivo absorption in rabbits revealed initial high TBS plasma levels followed by sustained levels over 24 h compared to immediate-release tablets.     

<Emphasis Type="Italic">Flavobacterium zaozhuangense</Emphasis> sp. nov., a new member of the family <Emphasis Type="Italic">Flavobacteriaceae</Emphasis>, isolated from metolachlor-contaminated soil

Strain ZZ-8^T, a Gram-negative, aerobic, non-spore-forming, non-motile, yellow-pigmented, rod-shaped bacterium, was isolated from metolachlor-contaminated soil in China. The taxonomic position was investigated using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain ZZ-8^T is a member of the genus Flavobacterium and shows high sequence similarity to Flavobacterium humicola UCM-46^T (97.2%) and Flavobacterium pedocola UCM-R36^T (97.1%), and lower (<?97%) sequence similarity to other known Flavobacterium species. Chemotaxonomic analysis revealed that strain ZZ-8^T possessed MK-6 as the major respiratory quinone; and iso-C_15:0 (28.5%), summed feature 9 (iso-C_17:1 w9c/C_16:0 10-methyl, 22.9%), iso-C_17:0 3-OH (17.0%), iso-C_15:0 3-OH (8.9%), iso-C_15:1 G (8.6%) and summed feature 3 (C_16:1 w7c/C_16:1 w6c, 5.7%) as the predominant fatty acids. The polar lipids of strain ZZ-8^T were determined to be lipids, a glycolipid, aminolipids and phosphatidylethanolamine. Strain ZZ-8^T showed low DNA–DNA relatedness with F. pedocola UCM-R36^T (43.23?±?4.1%) and F. humicola UCM-46^T (29.17?±?3.8%). The DNA G+C content was 43.3 mol%. Based on the phylogenetic and phenotypic characteristics, chemotaxonomic data and DNA–DNA hybridization, strain ZZ-8^T is considered a novel species of the genus Flavobacterium, for which the name Flavobacterium zaozhuangense sp. nov. (type strain ZZ-8^T?=?KCTC 62315 ^T?=?CCTCC AB 2017243^T) is proposed.