Search

A novel Gram-stain-negative, aerobic strain, designated Y22T, was isolated from peanut field soil in Laoshan Mountain in China. Cells of strain Y22T were rod-shaped and motile by a single flagellum. The strain was found to be oxidase- and catalase-positive. 16S rRNA gene sequence based on phylogenetic analysis indicated that strain Y22T belonged to the genus Pseudomonas, and showed the highest 16S rRNA gene sequence similarity of 99.0% to Pseudomonas pelagia JCM 15562T, followed by Pseudomonas salina JCM 19469T (98.4%), Pseudomonas sabulinigri JCM 14963T (97.9%), Pseudomonas bauzanensis CGMCC 1.9095T (97.6%) and Pseudomonas litoralis KCTC23093T (97.5%). The phylogenetic analysis based on multilocus sequence analyses with concatenated 16S rRNA, gyrB, rpoD and rpoB genes indicated that strain Y22T belonged to Pseudomonas pertucinogena lineage. The average nucleotide identity scores between strain Y22T and closely related species were 74.6–82.8%, and the Genome-to-Genome Distance Calculator scores were 16.4–44.9%. The predominant cellular fatty acids of strain Y22T were C18:1ω7c (29.6%), C17:0 cyclo (17.5%) and summed feature 3 (C16:1ω7c and/or C16:1ω6c) (17.4%). The genomic DNA G+C content was 57.9 mol%. On the basis of phenotypic characteristics, phylogenetic analyses and in silico DNA–DNA relatedness, a novel species, Pseudomonas laoshanensis sp. nov. is proposed. The type strain is Y22T (= JCM 32580T = KCTC 62385T = CGMCC 1.16552T).

Proteins are dominant executors of living processes. Compared to genetic variations, changes in the molecular structure and state of a protein (i.e. proteoforms) are more directly related to pathological changes in diseases. Characterizing proteoforms involves identifying and locating primary structure alterations (PSAs) in proteoforms, which is of practical importance for the advancement of the medical profession. With the development of mass spectrometry (MS) technology, the characterization of proteoforms based on top-down MS technology has become possible. This type of method is relatively new and faces many challenges. Since the proteoform identification is the most important process in characterizing proteoforms, we comprehensively review the existing proteoform identification methods in this study. Before identifying proteoforms, the spectra need to be preprocessed, and protein sequence databases can be filtered to speed up the identification. Therefore, we also summarize some popular deconvolution algorithms, various filtering algorithms for improving the proteoform identification performance and various scoring methods for localizing proteoforms. Moreover, commonly used methods were evaluated and compared in this review. We believe our review could help researchers better understand the current state of the development in this field and design new efficient algorithms for the proteoform characterization.

Peanut or groundnut (Arachis hypogaea L.), a legume of South American origin, has high seed oil content (45–56%) and is a staple crop in semiarid tropical and subtropical regions, partially because of drought tolerance conferred by its geocarpic reproductive strategy. We present a draft genome of the peanut A-genome progenitor, Arachis duranensis, and 50,324 protein-coding gene models. Patterns of gene duplication suggest the peanut lineage has been affected by at least three polyploidizations since the origin of eudicots. Resequencing of synthetic Arachis tetraploids reveals extensive gene conversion in only three seed-to-seed generations since their formation by human hands, indicating that this process begins virtually immediately following polyploid formation. Expansion of some specific gene families suggests roles in the unusual subterranean fructification of Arachis. For example, the S1Fa-like transcription factor family has 126 Arachis members, in contrast to no more than five members in other examined plant species, and is more highly expressed in roots and etiolated seedlings than green leaves. The A. duranensis genome provides a major source of candidate genes for fructification, oil biosynthesis, and allergens, expanding knowledge of understudied areas of plant biology and human health impacts of plants, informing peanut genetic improvement and aiding deeper sequencing of Arachis diversity.

A Gram-stain-negative, aerobic, mobile, and rod-shaped bacterium, designated JJ3T, was isolated from peanut rhizospheric soil in Qingdao, Shandong Province, China, and was characterized using a polyphasic approach. Strain JJ3T grew at 4–40 °C, at pH 5.0–9.0 and 0–4% NaCl. The strain was positive for both catalase and oxidase tests, and was able to degrade aflatoxin B1. According to the 16S rRNA gene sequence comparisons, the strain JJ3T was identified as a member of the genus Pseudomonas and was most closely related to Pseudomonas japonica JCM 21532T and Pseudomonas alkylphenolica JCM 16553T with sequence similarity of 99.0% and 98.9%, respectively. A multilocus sequence analysis (MLSA) of concatenating 16S rRNA, gyrB and rpoD gene sequences showed that strain JJ3T belonged to the Pseudomonas putida subcluster. Genomic comparison of strain JJ3T with its closest phylogenetic type strain using average nucleotide index (ANI) and digital DNA–DNA relatedness revealed 76.7–82.9% and 20.2–37.1%, respectively. All values were distinctly lower than the thresholds established for species differentiation. The predominant cellular fatty acids of strain JJ3T were C17:0 cyclo (24.0%), C16:0 (21.4%), summed features 3 (C16:1ω7c and/or C16:1ω6c) (11.5%) and summed features 8 (C18:1ω7c and/or C18:1ω6c) (10.5%). The major polar lipids of strain JJ3T were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The physiological, biochemical, and genetic characteristics support the assignment of JJ3T to the genus Pseudomonas, but are different to those of phylogenetically neighboring species to represent a novel species. The name Pseudomonas qingdaonensis sp. nov. is proposed, with JJ3T (= JCM 32579T = KCTC 62384T = CGMCC 1.16493T) as the type strain.

The best enzyme to prepare peanut peptides, papain, coupled with microwave irradiation was selected from five common proteases according to the results of the yield of peanut peptides [nitrogen solution index (NSI) in trichloroacetic acid (TCA), TCA-NSI] and the degree of hydrolysis (DH). The main factors that influenced the microwave-coupled enzymatic digestion method were optimized by response surface analysis. The optimal conditions obtained were as follows: microwave extraction time, 9.5 min; power, 600 W; substrate concentration, 4%; enzymatic reaction temperature, 50 °C; enzyme quantity, 6,500 U/g; pH, 7.1 (phosphate buffer, 0.05 mol/L). Under these conditions, TCA-NSI was 62.00% and DH was 25.89%, which is higher than that obtained with either protease hydrolysis or microwave hydrolysis alone.

Insect chitin was isolated from adult Holotrichia parallela by treatment with 1 M HCl and 1 M NaOH, following by 1% potassium permanganate solution for decolorization. The yield of chitin from this species is 15%. This insect chitin was compared with the commercial a-chitin from shrimp, by infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and elemental analysis. Both chitins exhibited similar chemical structures and physicochemical properties. Adult H. parallela is thus a promising alternative source of chitin.

A natural lectin from the seed of peanut Arachis hypogaea was purified by singlestep affinity chromatography using galactoside-coupled agarose. The native molecular mass of purified A. hypogaea lectin (PN-L) was 29 kDa. The lectin PN-L was detected for agglutinating activity, glycoinhibiting action and thermostability. The influence of pH on those activities was also tested. The results showed that PN-L could not agglutinate three kinds of human erythrocytes. But it showed a strong affinity to human A, B and O erythrocytes (RBC) treated by neuraminidase. Agglutinating activity of PN-L to neuraminidase treated human O erythrocytes was inhibited by lactose, raffinose, melibiose and D-galactose. The agglutinating activity of peanut seed lectin was stable up to 55°C and at pH 5.0-11.0. The results of MALDI-TOF- TOF analysis indicated that the protein PN-L showed highly homology with the Peanut Lectin Chain A protein (gi|1942899).

In order to exploit and utilize peanut industry resources and produce additional high value products, the use of microwave-assisted technology for extracting water soluble dietary fiber (SDF) from peanut hull was investigated. The factors that influence the SDF extraction were studied via response surface methodology. Regression models for the relationships between these factors and SDF extraction yield as well as the percentage content of non-starch polysaccharides (NSP) were established. The optimum parameters were a liquid-to-solid ratio of 1:16, microwave power of 700W, heating time of 6min, and heating temperature of 90°C. Under these conditions, the SDF extraction yield and NSP percentage content reached 2.68% and 56.06%, respectively. The IC50 values for SDF scavenging of hydroxyl free radicals, superoxide anion free radicals, and DPPH free radicals were 0.78 mg/mL, 6.66 mg/mL, and 5.12 mg/mL, respectively. Moreover, the iron and molybdenum reduction capacities were similar to 8.015 μg/mL and 28.505 μg/mL ascorbic acid reduction capacities, respectively.

The adult edible beetle Holotrichia parallela Motschulsky (Coleoptera: Scarabaeoidea) represents a traditional food source in China. Based on nutritional analyses, adult H. parallela is high in protein (70%) and minerals and low in fat. H. parallela contained approximately 10% chitin; the corrected protein content was 66%. Oleic acid and linoleic acid were the most abundant fatty acids. Of the total amino acids in H. parallela , 47.4% were essential amino acids. The amino acid scores were 87 and 100, based on the corrected crude and net protein contents, respectively; threonine was the limiting amino acid. In vitro protein digestibility was 78%, and the protein digestibility-corrected amino acid score was 89 based on the net protein content. Adult H. parallela may be a potential source of proteins and minerals for humans and animals.

The objective of this work is to obtain a new phosphate modified peanut protein (PMPP) with good physicochemical properties by using a simple and reliable method. For this purpose, response surface methodology (RSM), based on a Box-Behnken design, was used to optimise conditions for the microwave-assisted formation of phosphate modified peanut protein isolate (PPI) with sodium tripolyphosphate (STP) as the substrate. The results indicate that emulsification activity index (EAI) was optimised at 65.04 m(2)/g under the following conditions: substrate mass fraction of 10%, initial pH of 9.90, STP mass fraction of 7.70%, microwave power of 800 W, reaction temperature of 43.0 °C, and incubation time of 3.15 min. The emulsification activity of PPI improved after phosphate modification. Phosphatisation of both the Ser and Thr hydroxyl groups and the Lys amino groups was confirmed for the reaction between STP and PPI according to analysis of FTIR, XRD, TG/DTA, NMR-(31)P and SEM of the product. Physicochemical properties of PMPP were better than those of PPI.

The objective of this work is to provide a theoretical basis for preparing peanut antioxidant hydrolysate in order to improve its antioxidant activities. Therefore, response surface methodology (RSM) based on the Box-Behnken design was used to optimize ultrasonic-assisted enzymolysis for the purpose of preparing peanut antioxidant hydrolysate. Results indicated that the DPPH free radical scavenging activity of peanut hydrolysate could reach 90.06% under the following optimum conditions: ultrasonic power of 150.0 w, reaction temperature of 62.0 °C, incubation time of 25.0 min, and initial pH value of 8.5. The DPPH free radical scavenging rate of peanut hydrolysate from ultrasonic-assisted enzymolysis improved comparing with that of peanut hydrolysate from protease hydrolysis alone. The peanut antioxidant hydrolysate was found to display eight improved kinds of antioxidant activities. In conclusion, the optimal ultrasonic-assisted enzymolysis technology conditions described in this paper, appear to be beneficial for preparing peanut antioxidant hydrolysate.

Fruits of Broussonetia papyrifera from South China were analyzed for their total chemical composition, and antioxidant activities in ethanol and aqueous extracts. In the fruit of this plant, the crude protein, crude fat and carbohydrates was 7.08%, 3.72% and 64.73% of dry weight, respectively. The crude protein, crude fat and carbohydrates were 15.71%, 20.51% and 36.09% of dry weight, respectively. Fatty acid and amino acid composition of the fruit were analyzed. Unsaturated fatty acid concentration was 70.6% of the total fatty acids. The percentage of the essential amino acids (EAAs) was 40.60% of the total amino acids. Furthermore, B. papyrifera fruit are rich in many mineral elements and vitamins. Total phenolic content was assessed using the Folin-Ciocalteau assay, whereas antioxidant activities were assessed by measuring the ability of the two extracts to scavenge DPPH radicals, inhibit peroxidation, and chelate ferric ions. Their reducing power was also assessed. Results indicated that the aqueous extract of B. papyrifera was a more potent reducing agent and radical-scavenger than the ethanol extract. GC-MS analysis of the ethanol extract showed the presence of some acid-containing compounds. The changes in total phenolic content and antioxidant capacity in B. papyrifera from four different regions grown under normal conditions were assessed. The antioxidant activity of different extracts was positively associated with their total phenolic content. These results suggest that the fruit of B. papyrifera could be used in dietary supplement preparations, or as a food additive, for nutritional gain, or to prevent oxidation in food products.

Insects have been relatively unexplored as potential sources of natural antioxidants. We report the antioxidant activity of extracts of the adult large black chafer beetle Holotrichia parallela Motschulsky, a common crop pest in China. The antioxidant activity of the ethanolic extract (EE) and the water extract (WE) of adult H. parallela were evaluated by four different in vitro assays. EE showed potent metal-chelating activity and inhibition of lipid peroxidation. WE proved to be an excellent antioxidant in the scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and metal-chelating activity. Catechin was identified in the ethanolic extract and proteins were the main components in the water extracts. Both compounds could contribute to the antioxidant activity of the species. These results suggest that adult H. parallela might be used as a nutraceutical to alleviate oxidate-induced diseases and as a natural antioxidant additive in the food industry.