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Umami peptides from the enzymatic hydrolysate of Stropharia rugosoannulata were separated by ultrafiltration (UF) and gel filtration chromatography (GFC) combined with sensory evaluation and electronic tongue analysis. Fraction F3, with the strongest umami intensity, were identified by reversed-phase high performance liquid chromatography-tandem mass spectrometry (RP-HPLC-MS/MS). The identified peptides were synthesized and evaluated for their taste characteristics. The results showed that eight umami peptides were identified in fraction F3, namely ELWR, RLVDR, KPDNR, AHLRF, LDWDR, LAEWR, DDWWR and EGHKGW, and all of them possessed umami characteristics and umami-enhancing effects with thresholds ranging from 0.30 to 1.33 mmol/L and from 0.53 to 2.43 mmol/L, respectively. All peptides except LDWDR showed different degrees of umami improvement in monosodium glutamate (MSG) solution, ranging from 0.18% to 61.12%. ELWR, RLVDR, KPDNR, AHLRF and EGHKGW showed good umami-enhancing effects at low concentrations. The peak concentration of RLVDR and KPDNR for synergistic umami-enhancing effect was 5 mg/mL. LDWDR, LAEWR, DDWWR and EGHKGW reached the umami peak at 4 mg/mL. The amino acid composition and the spatial structure of umami peptides could affect their taste properties. The results of this study provide a theoretical basis for the development and utilization of umami peptides from S. rugosoannulata.

In order to explore the flavor composition profiles of fresh and dried Stropharia rugosoannulata and the key components determining its good flavor, the aroma and flavor components of fresh and dried samples prepared by four different drying methods, namely hot air drying (HAD), vacuum freeze drying (VFD), microwave drying (MWD), natural drying (ND) were analyzed. A total of 118 aroma compounds were detected. After drying, the aroma richness was significantly improved (P HAD > ND > fresh sample > MWD. A partial least squares regression model was established based on the sensory scores and the component data. The R2X, R2Y and Q2 of the first three principal components were 79.4%, 98.9%, and 0.974, respectively. The loading information showed that the interaction between aroma and taste characteristics was obvious. Variable importance in projection scores showed that sweet amino acids, 1-octene-3-ol, butyl-2-octenal and EUC were crucial for the good characteristic flavor of S. rugosoannulata. This study will provide a theoretical basis for subsequent screening of sample pretreatment methods and the development of flavor related products.

By the end of 2020, 83 silver deposits (or ore occurrences), including four super-large-scale deposits, nine large-scale deposits, 33 medium-scale deposits and 37 small-scale deposits or ore occurrences, have been proved. The amount of silver metal exceeds 86000 t with average grade of 100 g/t, which makes Daxing’ anling region one of the the most important silver ore belt in China. However, the metallogenic characteristics and metallogenesis need to be clarified. The silver deposits in the study area are classified into three main types, which are magmatic hydrothermal vein type, continental volcano-subvolcanic type and skarn type, respectively. The supergiant deposits include the Shuangjianzishan deposit (silver metal amount of 15214 t with average grade of 138 g/t), the Baiyinchagandongshan deposit (silver metal amount of 9446 t with average grade of 187 g/t), the Huaobaote deposit (silver metal amount of 6852 t with average grade of 170 g/t), and the Fuxingtun deposit (silver metal amount of 5240 t with average grade of 196 g/t). The silver deposits are mainly distributed in the central and south of the Daxing’anling area, and mainly formed in the Yanshanian period. The silver polymetallic deposits in the Daxinganling area are significantly controlled by regional faults and the junction zone of volcanic rock basins and their margins. The north-east trending deep faults are the most important ore-controlling structures in this area. The distribution of silver polymetallic deposits along the main faults is obvious, and the intersection area of multiple groups of faults often form important mine catchments. The Permian is the most important ore-bearing formation in this area, but some important silver polymetallic deposits occur in Mesozoic volcanic basins or pre-Mesozoic strata. The magmatic rocks related to mineralization are mainly intermediate acidic or acidic intrusions, intermediate acidic lavas, pyroclastic rocks, and small intrusions of ultra-shallow or shallow facies of the Yanshanian Period. The mineralization element combination is mainly determined by the elemental geochemical background of surrounding rocks or source layers. In addition, the type of deposit, the distance from the mineralization center, and the degree of differentiation of ore-forming rock mass are also important influence factors. The article analyzes the prospecting prospects of each silver deposit type in the study area, discusses the relationship between mineralization center and deep prospecting, and proposes that porphyry silver deposits should be paid attention to. In the prospecting and exploration of silver deposits, comprehensive evaluation and multi-target prospecting need to be strengthened because silver can coexist or be associated with a variety of metals.©2022 China Geology Editorial Office.

Objective To investigate the clinical symptoms and molecular biological characteristics in a family with oculopharyngeal muscular dystrophy (OPMD). Methods Clinical data of the family members were collected. Genomic DNA were isolated from peripheral blood of 6 family members including the probands for polymerase chain reaction (PCR). TA cloning followed by Sanger DNA sequencing was conducted for detecting PABPN1 gene mutations. Results The first symptom of the 4 family members in OPMD pedigree was ptosis at 50⁃years⁃old. The clinical symptoms of pharyngeal muscles involved in gradually dysphagia. Genetic testing found: the proband (Ⅱ3), the second sister of the proband (Ⅱ2), the fourth brother of the proband (Ⅱ4), and the fifth sister of the proband (Ⅱ5) had abnormal amplification of (GCN) repeat, (GCN)10/(GCN)13 in exon 1 of PABPN1 gene, which was identified in 4 members of the family who conducted the genetic testing. There was a dominant inheritance pattern in the lineage. The final diagnosis was OPMD, and the family was diagnosed as OPMD. Conclusions Clinical symptoms play a decisive role in the detection of the disease, thus genetic testing is the ctritical factor to the diagnosis and prevention of oculopharyngeal muscular dystrophy, which provides necessary information for choosing treatments and genetic counseling.

Litsea cubeba belongs to the Lauraceae family within the Magnoliids clade. Here, the authors assemble its genome and reveal divergence of inflorescence and sexual differentiation, the phylogenetic relationships across the Lauraceae and related species, and biosynthetic genes related to essential oil synthesis.

Abstract. Background:. Advanced technology has become a valuable tool in etiological studies of intellectual disability/global developmental delay (ID/GDD). The present study investigated the role of genetic analysis to confirm the etiology in ID/GDD patients where the cause of the disease was uncertain in central China. Methods:. We evaluated 1051 ID/GDD children aged 6 months to 18 years from March 2009 to April 2017. Data concerning basic clinical manifestations were collected, and the method of etiology confirmation was recorded. Genome-wide copy number variations (CNVs) detection and high-throughput sequencing of exons in the targeted regions was performed to identify genetically-based etiologies. We compared the incidence of different methods used to confirm ID/GDD etiology among groups with differing degrees of ID/GDD using the Chi-square or Fisher exact probability test. Results:. We recruited 1051 children with mild (367, 34.9%), moderate (301, 28.6%), severe (310, 29.5%), and profoundly severe (73, 6.9%) ID/GDD. The main causes of ID/GDD in the children assessed were perinatal factors, such as acquired brain injury, as well as single gene imbalance and chromosomal gene mutation. We identified karyotype and/or CNVs variation in 46/96 (47.9%) of cases in severe ID/GDD patients, which was significantly higher than those with mild and moderate ID/GDD of 34/96 (35.4%) and 15/96 (15.6%), respectively. A total of 331/536 (61.8%) patients with clear etiology have undergone genetic analysis while 262/515 (50.9%) patients with unclear etiology have undergone genetic analysis (χ2 = 12.645, P