Molecular analyses display the increasing diversity of Podostemaceae in China

Podostemaceae(riverweed family),one of the largest aquatic plant families in the world,comprises about 350 species in 51 genera placed in three subfamilies,Podostemoideae,Weddellinoideae,and Tristichoideae(Koi et al.,2022).Most Podostemaceae genera(~38)are monotypic or oligotypic,with a high level of endemism(Koi et al.,2018,2022).Members of Podostemaceae adhere to rocks in fast-flowing rivers,streams,or waterfalls in the subtropics and tropics(Koi et al.,2018).As an adaptation to fastrunning currents,the morphological structure of river-weeds tends to be extremely reduced,including a loss or reduction of primary shoots or roots(Koi and Kato,2007).The vegetative mass of these plants resembles lichens or bryophytes,and are thus known commonly as“dream bryophytes”(Philbrick and Retana,1998).Podostemaceae plants flower when the water level drops during the dry season.In recent years,anthropogenic factors and climate change have severely affected river weed habitats,decreasing populations of these plants.

Effects of Quercetin Extracted from Flower Buds of Sophora japonica cv.jinhuai on Proliferation and Apoptosis of Human Breast Cancer MCF-7 Cells

[Objectives]To investigate the effects of quercetin extracted from flower buds of Sophora japonica cv.jinhuai on the proliferation,apoptosis and migration of human breast cancer MCF-7 cells.[Methods]MTT assay,inverted microscope observation,hoechst33342 staining,flow cytometry(FCM)and wound healing assay were adopted to investigate the proliferation,morphological changes,apoptosis level and cell migration ability of human breast cancer MCF-7 cells,respectively.[Results]The morphological changes of cells in the treatment groups included gradually decreased number,reduced volume,vague cell contour,loose intercellular connection,uneven cytoplasm distribution and increased cell debris.With the increase of drug concentration,quercetin significantly inhibited the proliferation of human breast cancer MCF-7 cells(P<0.05).The number of apoptotic bodies increased gradually.When the concentration reached 100μmol/L,a large number of nuclear fragments appeared,and the level of apoptosis was statistically different(P<0.05).The mobility and migration ability of cells showed a decreasing trend,and the differences were statistically significant(P<0.05).[Conclusions]This study can provide experimental basis for clinical application of quercetin against breast cancer.

Integrated gut microbiota,plasma metabolomics and network pharmacology to reveal the anti-ischemic stroke effect of cooked rhubarb

Background:Cooked rhubarb(CR)is obtained by steaming raw rhubarb(Rheum palmatum L.,Rheum officinale Baill.,or Rheum tanguticum Maxim.ex Balf.)with millet wine.It is used as a traditional Chinese medicine for treating cerebral stroke,where patients often face severe constipation.This study explored the pharmacological effects and mechanisms of CR against ischemic stroke(IS)in rats.We used integrated analysis of gut microbiota,metabolomics,and network pharmacology.Methods:The compounds in CR were identified using LC-MS/MS.The impact of CR on rat middle cerebral artery occlusion/reperfusion(MCAO/R)-induced cerebral infarct size and brain tissue pathology was assessed through 2,3,5-triphenyl tetrazolium chloride and HE staining.Changes in hemorheology were measured by evaluating blood viscosity,and serum levels of pro-inflammatory cytokine were also determined.Gut microbiota composition was analyzed through 16S rRNA gene sequencing.Serum metabolites were examined using untargeted metabolomics and Spearman correlation analysis.The pseudo-germ-free test was used to determine whether tumour necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)improvement in IS are dependent on gut microbiota.Results:In vivo studies showed CR enhances neurobehavioral function in MCAO/R rats and reduces cerebral infarction area.CR also ameliorates brain and intestinal barrier damage caused by stroke.It also decreased inflammation and oxidative stress in IS rats.Furthermore,CR promotes the growth of Akkermansia and Verrucomicrobia,aiding in intestinal barrier repair.Notably,CR primarily influences the primary bile acid biosynthesis pathway.The pseudo-germ-free experiment and network pharmacology confirmed TNF-αand IL-1βas potential targets.CR relies on gut microbiota for its anti-inflammatory effects to improve IS.Conclusion:Cooked rhubarb offers neuroprotective benefits by enhancing beneficial bacteria abundance and regulating bile acid metabolism.It emerges as a potential therapeutic agent for IS.

Soil microorganisms alleviate the allelopathic effect of Eucalyptus grandis × E. urophylla leachates on Brassica chinensis

Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential of these tree species. The role of soil microbes in the allelopathic effect of leaf leachates of the hybrid tree Eucalyptus grandis x E. urophylla, was tested in Petri dish assays with Brassica chinensis as a receiver plant. Soils were collected from either a local garden (soil A) or a Eucalyptus plantation (soil B) and half of each soil was sterilized to remove microbes. These soils were then treated with E. grandis x E. urophylla leachates for 0-72 h. Seed germination of B. chinensis was significantly inhibited in soils treated with leaf leachates relative to untreated soils. The inhibitory effect of the leaf leachates was more pronounced in sterilized soils. Total phenolic content was obvious lower in nonsterile leachate-treated soils than in sterile soils. Biomass of B. chinensis was negatively correlated with the total phenolic content in soils. Our findings suggest that soil microbes can alleviate the allelopathic potential of Eucalyptus and thereby its negative impact on plant growth.

Response of spikelet water status to high temperature and its relationship with heat tolerance in rice

In rice, high-temperature stress(HT) during flowering results in decreased grain yield via a reduction in spikelet fertility;however, the effect of plant water status on spikelet fertility under HT remains unknown. To investigate the relationship between spikelet water status and spikelet fertility under HT, two experiments were performed under temperature-controlled conditions using four genotypes with varying tolerance to HT. Rice plants were exposed to HT for seven consecutive days during the flowering stage under three soil water treatments(soil water potential 0, -20, and -40 kPa), as well as under hydroponic conditions in a separate experiment. HT significantly decreased spikelet fertility, pollen fertility, and anther dehiscence under each of the three water treatments. HT significantly increased the spikelet transpiration rate, and this change was accompanied by a significant decrease in the internal temperature of the spikelets. HT decreased pollen grain diameter in heat-sensitive genotypes. HT had varying effects on the water potential of panicles and anthers but increased anther soluble-sugar concentration. Different aquaporin genes showed different expression profiles under HT, and the expression levels of PIPs for plasma membrane intrinsic proteins and TIPs for tonoplast intrinsic proteins increased in anthers but decreased in glumes.Correlation analyses showed that anther dehiscence and pollen(spikelet) fertility were tightly associated with anther water status, and the expression levels of almost all anther aquaporin genes were significantly correlated with anther dehiscence under HT. In summary, an increased spikelet transpiration rate and decreased internal spikelet temperature were associated with alleviation of the effects of HT in rice genotypes with varying degrees of heat tolerance, and the response of spikelet water status to HT, involving increased total expression of aquaporins and soluble sugar content, thereby improved pollen fertility,anther dehiscence, and spikelet fertility, especially in heat-resistant genotypes. The heat-resistant genotypes N22 and SY63 may adopt different approaches to reduce heat damage.

Effect of reforestation on annual water yield in a large watershed in northeast China

A simplified water balance model in conjunc- tion with an evapotranspiration （ET） model and cumulative forest cover data were used to quantify the changes in annual water yield in response to reforestation in a large watershed, northeast China. Cumulative forest cover increased by 22 %, leading to a significant decrease in estimated annual water yield. Reforestation increased ET （P = 0.0144）, resulting in a remarkable decrease （P = 0.0001） in estimated annual water yield according to the water balance model. Reforestation increased ET by 33 mm and decreased annual water yield by 38 mm per decade. The effect of reforestation on annual water yield can be quantified using a simplified water balance model in a large watershed, although our reforestation area was small （about 20 %） in relation to the total watershed area.

Structural Characteristics of Vessels in Three Families of Cycadopsida

The pinna of Cycasferruginea F.N. Wei （Cycadaceae）, pinnas or rachises ofStangeria eriopus （Kune） Baill. （Stangeriaceae）, Dioon holmgrenii De Luca, Sabato ＆ Vazq. Torres, Macrozamia moorei F. Muell. ex C. Moore （Zamiaceae） were macerated and dissociated by Jeffrey＇s technique, rinsed with water, dehydrated and gold-plated for observation with scanning electron microscopes. The results showed that the pinna and rachis of the leaf tissues of the four cycad species possess many vessel elements and a few tracheid elements in the conducting tissue of the xylem. Annular, spiral, scalariform, pitted and reticulate vessels and some transitional types, including scalariform-pitted, scalariform-reticulate and reticulate-pitted vessels, were observed in the conducting tissues. The characteristics of the vessels of each species, and the evolutionary relation of four genera of cycads were analyzed. Compared with those of angiosperms, the structural characters of vessels of cycad are at the moderate level of evolution and more advanced than some primitive taxa of angiosperms and ferns. Vessels have been discovered in many genera of ferns, which are even more primitive than cycads. In many ferns, only vessel elements, but no tracheids are found in vascular tissue. In the present study, the authors discovered vessels in different genera of three families ofcycads which showed that the existence of vessels in primitive plant taxa is a widespread phenomenon. Vessel elements in vascular tissues of cycads have probably allowed cycads to adapt to various environmental stresses and enabled their persistence over their long evolutionary history. Cycads are the most primitive of the extant seed plants and the widespread existence of vessels in the group has broad implications for plant systematics, evolution and comparative morphology.

Research Progress of Triterpenoid Secondary Metabolites in Cucurbitaceae Plants

In this paper,the advances in study on triterpenoids in Trichosanthes,Hemsleya,Gynostemma,Actinostemma and Siraitia Merr. plants were reviewed.Terpenoids are the main secondary metabolites of Cucurbitaceae and have obvious pharmacological activity. It is noteworthy that in these plants,there are a variety of triterpenoids,which are diverse in structure. Triterpenoid saponins have greater potential for development.

Advances in the studies on symbiotic arbuscular mycorrhizal fungi of traditional Chinese medicinal plants

Arbuscular mycorrhizal(AM)fungi reside in the rhizosphere and form mutualistic associations with plant roots.They promote photosynthesis,improve stress resistance,and induce secondary metabolite biosynthesis in host medicinal plants.The AM fungi that are symbiotic with medicinal plants comprise a wide array of species and have abundant germplasm resources.Though research on the AM fungi in medicinal plants began relatively recently,it has nonetheless become an investigative hot spot.Several scholars have explored the diversity and the growth-promoting effects of mycorrhizal fungi in hundreds of medicinal plants.Current research on symbiotic AM fungi in medicinal plants has focused mainly on the effects of inoculating host plants with symbiotic mycorrhizal fungi.However,research on the symbiotic AM fungi in medicinal plants continues to expand,and further study is required to determine the mechanisms by which AM fungi interact with host plants.This paper introduces the diversity of symbiotic AM fungi of medicinal plants and the effects of AM fungi on rhizosphere soil of medicinal plants,including soil structure,microbiota,enzyme activities,etc.This review focuses on the effects of AM fungi on medicinal plants,including antioxidant enzyme systems,drought resistance,nutrient absorption profiles of macroand micronutrients,accumulation of secondary metabolites such as terpenes,phenolic compounds,and nitrogenous compounds,and prevention of diseases.This review is expected to provide a reference for the application of AM fungi in medicinal plant cultivation,biological control,resource conservation,and the sustainable development of the traditional Chinese medicine industry.

Productivity and the Survival Rate after Winter Management of Seven Tropical Forage Accessions in Subtropical Region of China

Forage production and quality of five tropical grass accessions (Guimu-1 hybrid elephant grass (PG1), Mulato II (M II), Ubon paspalum (PU), hybrid elephant grass (PH) and Reyan 11 paspalum (PR11)) and two tropical legume accessions (Reyan 5 stylo (SR5) and Ubon stylo (SU)) were evaluated in a field experiment in a subtropical area with hot summers and cold winters in Guangxi, China. Three forage stubble cover managements: no cover (CK), dry mass cover (MC) and plastic cover (PC) were applied at the end of the summer period to evaluate cold tolerance and accession survival over the winter. Photosynthesis measurements were taken from the forages in mid-summer. The results showed that PG1 accession produced significantly higher dry matter yields (67.0 t·ha-1) than the other grass and legume accessions. Legume accessions SU and SR5 produced much less dry matter (6.4 - 7.2 t·ha-1) compared to the grasses. M II, PU and PR11 contained the largest proportion of leaf. PG1 and PH showed good cold tolerance (survival rate >85%) under -1°C conditions without any cover management. PR11 had better cold tolerance than PU. M II exhibited very poor winter survival under no cover and with massive cover, and only survived well under plastic cover. The two stylo accessions died completely under all winter cover management treatments. In the growing season, under a given photosynthesis photon flux density (PPFD) = 1500 μmol m-2 s-1, the net photosynthesis rate Pn of all the seven accessions was above 28 μmol m-2 s-1, of which hybrid elephant grass and M II were above 42 μmol m-2 s-1. Though these 7 tropical accessions yielded high production in the grow season, stylo and M II are sensitive to cold in subtropical region of Guangxi. The result suggests that PG1 and PU are good accessions and can be used as productive perennial pasture, while stylo and M II are simply considered as annual one. Additionally, if paspalum was trained in cool region before being introduced to subtropical region, it may present both productivity and enhancive cold tolerance.

Optimization of Solid-state Fermentation Conditions of Sophora japonica cv.jinhuai by Response Surface Methodology

[Objectives]To optimize the solid-state fermentation process of Flos Sophorae Immaturus by Penicillium with Sophora japonica cv.jinhuai as raw material.[Methods]The fermentation conditions were optimized by single factor experiment and response surface methodology with quercetin content as the dependent variable.[Results]According to the established model,the optimal fermentation process of Flos Sophorae Immaturus was obtained as follows:temperature 29.97℃,time 6.88 d,rotation speed 180.86 rpm,inoculation amount 3.93 mL,and the expected content of quercetin was 34.8053 mg/g.Based on this,the fermentation parameters were adjusted,and the actual content was 33.67 mg/g,which was close to the predicted value.[Conclusions]The optimization of fermentation process of Flos Sophorae Immaturus by response surface methodology provides a reference for the development and utilization of this medicinal material.

Diurnal Variation of Photosynthetic Physiological Characteristics of Kadsura coccinea(Lem.)A.C.Smith

[Objectives]This study was conducted to investigate the diurnal variations of photosynthetic and physiological characteristics in 3-year-old Kadsura coccinea(Lem.)A.C.Smith plants.[Methods]A Li-6400 portable photosynthetic system was used to study the diurnal variations of the photosynthetic physiological characteristics of K.coccinea.[Results]The diurnal variation of the net photosynthetic rate(Pn)of K.coccinea leaves showed a"double peak"curve,and there was a lunch break at noon.The maximum value of Pn[4.51 mmol/(m^(2)·s)]appeared at 10:00,and the daily average Pn was 3.98 mol/(m^(2)·s);and the stepwise regression analysis showed that photosynthetically active radiation(PAR)and stomatal conductance(Gs)were the main factors affecting Pn.The partial correlation analysis and path analysis showed that the order of effects on Pn was Gs>PAR.[Conclusions]This study provides a reference for further research on the development and utilization of K.coccinea.

Development and structure-activity relationships of tanshinones as selective 11β-hydroxysteroid dehydrogenase 1 inhibitors

11β-Hydroxysteroid dehydrogenase 1(11β-HSD1)represents a promising drug target for metabolic syndrome,includ-ing obesity and type 2 diabetes.Our initial screen of a collection of natural products from Danshen led to the identi-fication of tanshinones as the potent and selective 11β-HSD1 inhibitors.To improve the druggability and explore the structure-activity relationships(SARs),more than 40 derivatives have been designed and synthesized using tanshinone IIA and cryptotanshinone as the starting materials.More than 10 derivatives exhibited potent in vitro 11β-HSD1 inhibitory activity and good selectivity over 11β-HSD2 across human and mouse species.Based on the biological results,SARs were further discussed,which was also partially rationalized by a molecular docking model of 1 bound to the 11β-HSD1.Remarkably,compounds 1,17 and 30 significantly inhibited 11β-HSD1 in 3T3-L1 adipocyte and in livers of ob/ob mice,which merits further investigations as anti-diabetic agents.This study not only provides a series of novel selective 11β-HSD1 inhibitors with promising therapeutic potentials in metabolic syndromes,but also expands the boundaries of the chemical and biological spaces of tanshinones.

Technical Regulations for Standardized Planting of Rare and Multi-purpose Wild Fruit Kadsura coccinea

The cultivation technology were standardized for improving the yield and quality,and the commodity value and the competitiveness of fruit market,and solving the bottleneck problem—fruit quality and yield that affect the industrial development of rare and multi-purpose wild fruit Kadsura coccinea(Lem.)A.C.Smith.Through the investigation of K.coccinea production area and planting area,collection and analysis of fruit samples,it was found that in most planting area,the varieties of K.coccinea were mixed,with great differences in fruit quality and yield,which makes it impossible to realize large-scale planting.In view of these problems,a series of studies have been carried out and the technical regulations for standardized planting of rare and multi-purpose wild fruit K.coccinea were formulated.

Effects on Zinc Stress on Stress-Resistance Physiological and Biochemical Indexes of Jatropha curcas seedlings

Jatropha curcas seedlings were cultured for 21 d under 6 zinc concentrations of 0,25,50,100,200,400 mg/l to study the effects of ZnS O4 stress on the mechanism of resistance to heavy metal stress of J. curcas seedlings. The results showed that with the increase of stress concentration,the content of chlorophyll-a decreased and the activity of POD first increased and then maintained at a certain level or decreased slowly. The contents of soluble sugar,malondialdehyde,soluble protein and free proline increased,and the root activity increased first and then decreased. The relative conductivity of J. curcas seedlings decreased first and then increased,which indicated that the leaves of J. curcas seedlings had some adaptability and self-repairing capability under zinc toxicity stress,but the adaptability and self-repair ability were limited.

Primulina titan sp.nov.(Gesneriaceae)from a Limestone Area in Northern Guangxi,China

A new species of Gesneriaceae,Primulina titan,is described and photographed from northern Guangxi,China.It resembles P.hunanensis,but can be distinguished by combined morphological characters of leaf,bract,corolla,stamen and pistil.We found only one population with approx.800 mature individuals at the type locality.This species is provisionally assessed as vulnerable[VU D1]using IUCN criteria.

Spatial-temporal Distribution and Influencing Factors of Urban Carbon Emissions under the Background of Carbon Emission Reduction:A Case Study of Guangxi Autonomous Region

Based on the panel data of Guangxi from 2005 to 2017,the spatiotemporal characteristics and determinants of urban carbon emissions in Guangxi were analyzed using the extended STIRPAT model and the Geographically and Temporally Weighted Regression(GTWR)model.The main findings of our research can be summarized as follows.While the total carbon emissions of cities in Guangxi consistently increased from 2005 to 2014,the growth trend slowed after 2014,leading to a stabilization in the total emissions.In addition,there are significant differences in the total carbon emissions among the cities.The central and northeastern regions have higher emissions,while the southwestern region has lower emissions.Finally,there are variations in the degrees and directions of the impacts that factors have on carbon emissions among the different time periods and cities.Urban land use is a key factor driving carbon emissions,and it has a negative impact on most cities in Guangxi.Meanwhile,factors such as industrial structure,population urbanization,population concentration,and economic growth have significant positive effects on carbon emissions in Guangxi.The influence of urban roads on carbon emissions is generally positive,while the degree of openness to the outside world and environmental regulations has relatively weaker impacts on emissions.In summary,in order to promote the low-carbon transition of Guangxi and achieve high-quality development,the cities in Guangxi should implement differentiated urban carbon reduction strategies that are focused on optimizing urban land use and industrial structure.

Genomic divergence and mutation load in the Begonia masoniana complex from limestone karsts

Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.However,these effects are rarely studied in limestone karst plants.Here,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(B.liuyanii,B.longgangensis,B.masoniana and B.variegata)and investigated genomic divergence and genetic load for these four species.Our analyses revealed four distinct clusters corresponding to each species within the complex.Notably,there was only limited admixture between B.liuyanii and B.longgangensis occurring in overlapping geographic regions.All species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate fluctuations.We detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic isolation.We found that isolated populations of B.masoniana have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious mutations.These findings underscore the urgency to prioritize conservation efforts for these isolated population.This study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of inbreeding.Moreover,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.

Fresh Processing Technology in Polygonatum odoratum Production Area and Its Comparison with Traditional Processing

[Objectives]To compare the effects of traditional processing and fresh processing on the quality of Polygonatum odoratum decoction piece.[Methods]The effects of fresh processing and traditional processing on the quality of P.odoratum decoction piece were compared and analyzed with appearance characteristics,total ash content,extract content,total polysaccharides content,and total flavonoids content as the evaluation indexes.[Results]Fresh processing method in different production areas has different effects on P.odoratum decoction piece.P.odoratum was dried in oven of 50℃.When moisture content was 41.44%-59.67%,it was cut.After complete drying at 50℃,the moisture content of dried P.odoratum was 8.94%-9.60%,and ethanol-soluble extract content was 77.29%-78.20%,and water-soluble extract was 77.7%-78.14%.At this time,the appearance characteristics of section of P.odoratum decoction piece were better than that of traditional processing,which was yellowish white.The total polysaccharide content was higher than that of traditional processing,and the content of total flavonoids was statistically significant different from that of traditional processing.[Conclusions]The quality of P.odoratum decoction piece by fresh processing is better than that of the traditional processing,and it is feasible to use fresh processing.

Interactions between Two Fungi Strains during Litter Decomposition through a Microcosm Experiment: Different Degradative Enzyme Activities

Fungi are the key agents in litter decomposition in forest ecosystems. However, the specific roles of the interactions between different fungal species during litter decomposition process are unclear. To evaluate the interactions, two fungi strains with significantly different morphs were isolated from the soils of Quercus acutissima forest and Pinus massoniana forest, and inoculated in the litter powder of Quercus acutissima leaves and Pinus massoniana needles with grown separately and in coexistence equally through a microcosm experiment. The enzyme activities were determined as a proxy for microbial activities. The results showed that the degradative enzymes involved in litter decomposition showed varying dynamics pattern during the incubation period. The interactions between the two fungi strains are synergism, and benefit to each other according to enzyme activities, suggesting that a fungi strain growth was accelerated by the presence of other fungi strain during litter decomposition process. However, the interactions of the two fungi strains were bilateral antagonism inoculated in the litter powder of Quercus acutissima leaves according to cellobiohydrolase activities. The synergism, despite bilateral antagonism in an exceptional case, may be an important factor controlling the fungal colonization and growth on litter substrate. The results implied that more fungal species may accelerate litter decomposition rates due to their mutual cooperation.