Search

Supervolcanic eruptions induced abrupt global cooling (roughly at a rate of ~1ºC/year lasting for years to decades), such as the prehistoric Yellowstone eruption released, by some estimates, SO2 about 100 times higher than the 1991 Mt. Pinatubo eruption. An abrupt global cooling of several ºC, even if only lasting a few years, would present immediate and drastic stress on biodiversity and food production - posing a global catastrophic risk to human society. Using a simple climate model, this paper discusses the possibility of counteracting supervolcanic cooling with the intentional release of greenhouse gases. Although well-known longer-lived compounds such as CO2 and CH₄ are found to be unsuitable for this purpose, select fluorinated gases (F-gases), either individually or in combinations, may be released at gigaton scale to offset most of the supervolcanic cooling. We identify candidate F-gases (viz. C4F6 and CH3F) and derive radiative and chemical properties of ‘ideal’ compounds matching specific cooling events. Geophysical constraints on manufacturing and stockpiling due to mineral availability are considered alongside technical and economic implications based on present-day market assumptions. The consequences of F-gas release in perturbing atmospheric chemistry are discussed in the context of those due to the supervolcanic eruption itself. The conceptual analysis here suggests the possibility of mitigating certain global catastrophic risks via intentional intervention.

Archaeal membrane lipids are widely used for paleotemperature reconstructions, yet these molecular fossils also bear rich information about ecology and evolution of marine ammonia-oxidizing archaea (AOA). Here we identified thermal and nonthermal behaviors of archaeal glycerol dialkyl glycerol tetraethers (GDGTs) by comparing the GDGT-based temperature index (TEX86) to the ratio of GDGTs with two and three cyclopentane rings (GDGT-2/GDGT-3). Thermal-dependent biosynthesis should increase TEX86and decrease GDGT-2/GDGT-3 when the ambient temperature increases. This presumed temperature-dependent (PTD) trend is observed in GDGTs derived from cultures of thermophilic and mesophilic AOA. The distribution of GDGTs in suspended particulate matter (SPM) and sediments collected from above the pycnocline—shallow water samples—also follows the PTD trend. These similar GDGT distributions between AOA cultures and shallow water environmental samples reflect shallow ecotypes of marine AOA. While there are currently no cultures of deep AOA clades, GDGTs derived from deep water SPM and marine sediment samples exhibit nonthermal behavior deviating from the PTD trend. The presence of deep AOA increases the GDGT-2/GDGT-3 ratio and distorts the temperature-controlled correlation between GDGT-2/GDGT-3 and TEX86. We then used Gaussian mixture models to statistically characterize these diagnostic patterns of modern AOA ecology from paleo-GDGT records to infer the evolution of marine AOA from the Mid-Mesozoic to the present. Long-term GDGT-2/GDGT-3 trends suggest a suppression of today’s deep water marine AOA during the Mesozoic–early Cenozoic greenhouse climates. Our analysis provides invaluable insights into the evolutionary timeline and the expansion of AOA niches associated with major oceanographic and climate changes.

Throughout Earth's history, CO2 is thought to have exerted a fundamental control on environmental change. Here we review and revise CO2 reconstructions from boron isotopes in carbonates and carbon isotopes in organic matter over the Cenozoic—the past 66 million years. We find close coupling between CO2 and climate throughout the Cenozoic, with peak CO2 levels of ∼1,500 ppm in the Eocene greenhouse, decreasing to ∼500 ppm in the Miocene, and falling further into the ice age world of the Plio–Pleistocene. Around two-thirds of Cenozoic CO2 drawdown is explained by an increase in the ratio of ocean alkalinity to dissolved inorganic carbon, likely linked to a change in the balance of weathering to outgassing, with the remaining one-third due to changing ocean temperature and major ion composition. Earth system climate sensitivity is explored and may vary between different time intervals. The Cenozoic CO2 record highlights the truly geological scale of anthropogenic CO2 change: Current CO2 levels were last seen around 3 million years ago, and major cuts in emissions are required to prevent a return to the CO2 levels of the Miocene or Eocene in the coming century. ▪ CO2 reconstructions over the past 66 Myr from boron isotopes and alkenones are reviewed and re-evaluated. ▪ CO2 estimates from the different proxies show close agreement, yielding a consistent picture of the evolution of the ocean-atmosphere CO2 system over the Cenozoic. ▪ CO2 and climate are coupled throughout the past 66 Myr, providing broad constraints on Earth system climate sensitivity. ▪ Twenty-first-century carbon emissions have the potential to return CO2 to levels not seen since the much warmer climates of Earth's distant past.

Haptophyte algal biomarkers called alkenones are widely used to reconstruct atmospheric CO2 in Earth’s Cenozoic history. This method is based on the notion that the algal carbon isotope fractionation during photosynthesis, as represented by ep37:2, is a function of seawater CO2 concentration and algal physiology. Constraining the algal physiological parameter, known as the ‘b’ term, is the key for successful applications of the alkenone-CO2 method. Using sensitivity analyses, we show that the growth rate (μ), cell size (r), and membrane permeability (P) are the most important variables to determine b. For all life on Earth, body size is a key factor that regulates metabolic rates. Exploiting the interdependence between phytoplankton cell size and growth rate, and specifically, the r – μ relationship for coccolithophores, we show that the length of fossil coccoliths (Lcoccolith) produced by ancient alkenone-synthesizers can be used to estimate r and therefore μ. Combining our new Lcoccolith data and published ep37:2 from the South China Sea Site MD01-2392, existing results from ODP Site 925, and ice core CO2, we determined the cell membrane permeability (P = 5.09 × 10−5 m s−1) for the Pleistocene community employing a bootstrap resampling technique. These new methods of constraining r, μ and P, combined with proxy-derived temperature (T), led us to rebuild b as a variable for each sample individually, which is subsequently used for alkenone-CO2 calculations. Application of this approach established pCO2 of the last 3 glacial-interglacial cycles, which turns out to be comparable with the ice core data in both the amplitude of changes and absolute values. It also reconciles the published Eocene – Oligocene alkenone-CO2 data which showed large geographical differences, with the new estimates much more consistent among different sites, and in line with other proxy-based results and ice sheet model predictions.

is an important material in the food industry, and XuanMugua is the only one which is allowed to serve as a homology of medicine and food in China. This study was conducted to develop an effective ...

Pedogenic carbonate is an invaluable archive for reconstructing continental paleoclimate and paleoecology. The δ13C of pedogenic carbonate (δ13Cc) has been widely used to document the rise and expansion of C4 plants over the Cenozoic. This application requires a fundamental presumption that in soil pores, soil-respired CO2 dominates over atmospheric CO2 during the formation of pedogenic carbonates. However, the decoupling between δ13Cc and δ13C of soil organic matter (δ13CSOM) have been observed, particularly in arid regions, suggesting that this presumption is not always valid. To evaluate the influence of atmospheric CO2 on soil δ13Cc, here we performed systematic δ13C analyses of paleosols across the Chinese Loess Plateau, with the sample ages spanning three intervals: the Holocene, the Late Pleistocene, and the mid-Pliocene warm period. Our paired δ13Cc and δ13CSOM data reveal broadly divergent trending patterns. Using a two-component CO2-mixing model, we show substantial incorporations of atmospheric CO2 (up to 60%) into soil pore space during carbonate precipitation. This result readily explains the enrichment of δ13Cc and its divergence from δ13CSOM. As a consequence, δ13C of pedogenic carbonates formed under semiarid and/or arid conditions are largely driven by regional aridity through its control on soil CO2 composition, and thus cannot be used to evaluate the relative abundance of C3 versus C4 plants. Nonetheless, these carbonates can be applied for atmospheric CO2 reconstructions, even for periods with low CO2 levels.

Organic carbon buried in marine sediment serves as a net sink for atmospheric carbon dioxide and a source of oxygen

The alkenone-pCO2 method is one of the most widely used approaches to reconstruct atmospheric CO2 in the Cenozoic. The method depends upon fractionation of stable carbon isotopes during algal photosynthesis, expressed as ep37:2, and a physiological scaling parameter, b, that accounts for biological factors such as growth rate, cell size, and membrane permeability. Alkenone-derived CO2 records for the late Pleistocene, however, are poorly correlated with ice core CO2, challenging the classic model that considers most of the CO2 used for coccolithophore photosynthesis to be acquired through simple diffusion. In this study, we investigate the nature of the b term and the underlying patterns of the sensitivity of ep37:2 to pCO2 changes. We generated two new ep37:2 records from the South China Sea (MD01-2392) and tropical Atlantic Ocean (ODP 668B) and compiled other published ep37:2 records over glacial-interglacial cycles. Using the ep37:2 data, ocean temperature estimates, and ice core CO2, we were able to back-calculate the corresponding values of b. At all locations, b varies over glacial cycles. The highest values of b correspond to peak interglacial stages, indicating that the phytoplankton growth rate is faster or cell size is smaller during interglacials than during glacial periods. We further show that the range of ep37:2 between glacial and interglacial conditions, Δep37:2, scales with growth conditions, consistent with the predictions of the carbon isotope fractionation model based on CO2 diffusion. In other words, the sensitivity of ep37:2 to pCO2 changes increases where the modern b values are large, contradicting the recommendations that oligotrophic sites are the best for alkenone-CO2 applications because of the presumed stability of b. Using the average back-calculated b value for each site, the composite pCO2 estimates from MD01-2392 and ODP 668B – the two sites with adequate Δep37:2 sensitivity – show broad agreement with the ice core CO2 record.

The world-renowned Miocene Clarkia paleolake in northern Idaho (USA) is closely associated with Columbia River Basalt Group volcanism. The flood basalt dammed a local drainage system to form the paleolake, which preserved a plant fossil Lagerstätte in its deposits. However, the precise age and temporal duration of the lake remain unsettled. We present the first unequivocal U-Pb zircon ages from interbedded volcanic ashes at the P-33 type location, constraining the deposition to 15.78 ± 0.039 Ma. Using micro–X-ray fluorescence and petrographic and spectral analyses, we establish the annual characteristics of laminations throughout the stratigraphic profile using the distribution of elemental ratios, mineral assemblages, and grain-size structures, as well as organic and fossil contents. Consequently, the ~7.5-m-thick varved deposit at the type location P-33 represents ~840 yr of deposition, coincident with the end of the main phase of Columbia River Basalt Group eruptions during the Miocene Climate Optimum. The timing and temporal resolution of the deposit offer a unique opportunity to study climate change in unprecedented detail during global warming associated with carbon-cycle perturbations.

Detailed methodology, supplemental figures, and separate data files containing raw U-Pb zircon data, μ-XRF elemental ratios, and color intensity variation.

Acromioclavicular joint dislocation is a common sports injury disease, surgical treatment to restore the acromioclavicular joint stability, including stability and vertical stability level. However, vertical stability is often neglected. So we did a retrospective study enrolled 38 patients using Endobutton reconstruction and suture repair (Group A) with those using single Endobutton (Group B). The perioperative assessments contained coracoclavicular distance (CCD), Constant-Murley shoulder joint score, University of California at Los Angeles (UCLA) shoulder joint score and the difference between bilateral CCD 12 months postoperatively. The evaluation of group A was significantly better than group B. Constant-Murley scores and UCLA shoulder scores preoperatively were significantly higher than those after operation. The postoperative CCD of the two groups was lower than that before surgery. CCD between the affected shoulder and another postoperatively was no difference in group A, but was different in group B. The difference of postoperative CCD of the two groups was different. Afterward, we evaluated the stress and deformation around the acromioclavicular joint by finite element analysis and found that the stress dispersion and displacement reduction enhanced the stability of acromioclavicular joint. Thus, reconstruction of coracoclavicular ligament with Endobutton and sutures repair can increase the stability of acromioclavicular joint.

The future in the past A major cause of uncertainties in climate projections is our imprecise knowledge of how much warming should occur as a result of a given increase in the amount of carbon dioxide in the atmosphere. Paleoclimate records have the potential to help us sharpen that understanding because they record such a wide variety of environmental conditions. Tierney et al. review the recent advances in data collection, statistics, and modeling that might help us better understand how rising levels of atmospheric carbon dioxide will affect future climate. Science , this issue p. eaay3701

When the Earth warms, the high latitudes often warm more than the low latitudes, a phenomenon commonly known as high latitude amplification. Although high latitude amplification has been observed by both climate data and models, the trajectory of high latitude amplification in our future changing climate is uncertain. Pacific-wide reconstructions of sea surface temperature variability from past climates are important for establishing the historical records of high latitude amplification. Multiple extratropical temperature records have been established for the past 10 million years (Myr). However, it is debated whether the warmest end member, the Western Pacific Warm Pool (WPWP), warmed during the late Miocene (~12 to 5 million years ago, Ma) and Pliocene (5 to 3 Ma). Here we present new multi-proxy, multi-site paleotemperature records from the WPWP. These results, based on lipid biomarkers and foraminiferal Mg/Ca, unequivocally show warmer temperatures in the past, and a secular cooling over the last 10 Myr. We combine these new data, along with the previously established paleotemperature records, to reveal a persistent pattern of change in the Pacific described by a high latitude amplification factor of ~1.7, which does not seem to be affected by the major climate changes over the past 10 Myr. The evolution of spatial temperature gradients in the Pacific is also evident in climate model output and instrumental observations covering the last 160 years, and thus appears to be a robust and predictable feature of the climate system. These results therefore confirm that climate models can capture the major features of past climate change, providing increased confidence in their predictions of future patterns that are likely to be similar to those reconstructed here.

The phenols in Diaphragma juglandis fructus (DJF), walnut pellicle (WP), and flowers of Juglans regia (FJR) from walnut were extracted using three methods (methanolic condensation reflux extraction, ultrasonic wave extraction, and enzyme assisted-extraction), and phenolics and antioxidant capacities of different extractions were compared. Overall, 50 phenolics were identified by HPLC-MS/MS with 41 compounds in DJF, 32 in WP, and 29 in FJR. It was observed that tannins in WP was higher than those in DJF and FJR. As for PCA, more than 70% of the variance was explained with the obvious comparison between the phenolic constituents. The phenolics in walnut contributed to remarkable antioxidant effect, with the highest effect observed in WP. This study presents the analysis and comparison of the phenols can be further extended for the development of functional walnut instant foods.

The first of the ‘Big Five’ Phanerozoic mass extinctions occurred in tandem with an episode of glaciation during the Hirnantian Age of the Late Ordovician. The mechanism or change in the carbon cycle that promoted this glaciation, thereby resulting in the extinction, is still debated. Here we report new, coupled nitrogen isotope analyses of bulk sediments and chlorophyll degradation products (porphyrins) from the Vinini Creek section (Vinini Formation, Nevada, USA) to show that eukaryotes increasingly dominated marine export production in the lead-up to the Hirnantian extinction. We then use these findings to evaluate changes in the carbon cycle by incorporating them into a biogeochemical model in which production is increased in response to an elevated phosphorus inventory, potentially caused by enhanced continental weathering in response to the activity of land plants and/or an episode of volcanism. The results suggest that expanded eukaryotic algal production may have increased the community average cell size, leading to higher export efficiency during the Late Katian. The coincidence of this community shift with a large-scale marine transgression increased organic carbon burial, drawing down CO2 and triggering the Hirnantian glaciation. This episode may mark an early Palaeozoic strengthening of the biological pump, which, for a short while, may have made eukaryotic algae indirect killers. Enhanced algal productivity during the Late Ordovician may have led to carbon drawdown and the inception of the Hirnantian glaciation, according to sediment geochemistry and carbon cycle modelling.

Objective To design a WeChat mini program called Chinese Syndrome Differentiation Learning Platform (CSDLP) on smartphone to improve health literacy.Methods The developer tools of WeChat (Version: v1.01.170925) were used for designing and debugging the mini program. SPSS17.0 was used for statistical purposes. “View container”“Basic content”“Form component”“Navigation” and “Media components” were used for the development of the WeChat mini program. The detailed method was referred to https://mp.weixin.qq.com/debug/wxadoc/dev/.Results A WeChat mini program called CSDLP was developed. This program has three major functions which are WeChat reading, WeChat class and WeChat syndrome differentiation. The official test report showed that there were no functionality errors for the seven android smartphones (referred to as A, B, C, D, E, F and G) that CSDLP was tested on. Statistical analysis results showed that the average memory in D, E, F and G was lower than in A, B and C. Average ratio was the highest in F and the lowest in G. The average loading time was the same for all smartphones. The audio database for diagnostics using traditional Chinese medicine (TCM) and a lecture video database were based on diagnostic textbook. Our team built a syndrome differentiation database which included 51 diseases.Conclusion CSDLP can improve knowledge visualization, studying process, and information sharing in terms of the training and development of new techniques for syndrome differentiation and treatment in TCM, and it can provide a better illustration for people to understand TCM. Keywords: Syndrome differentiation and treatment, Learning platform, Smartphone, WeChat Program

Cold, nutrient- and CO2-rich waters upwelling in the eastern equatorial Pacific (EEP) give rise to the Pacific cold tongue. Quasi-periodic subsidence of the thermocline and attenuation in wind strength expressed by El Nino conditions decrease upwelling rates, increase surface-water temperatures in the EEP, and lead to changes in regional climates both near and far from the equatorial Pacific. EEP surface waters have elevated CO2 concentrations during neutral (upwelling) or La Nina (strong upwelling) conditions. In contrast, approximate air–sea CO2 equilibrium characterizes El Nino events. One hypothesis proposes that changes in physical oceanography led to the establishment of a deep tropical thermocline and expanded mixed-layer prior to 3 million years ago. These effects are argued to have substantially reduced deep-water upwelling rates in the EEP and promoted a “permanent El Nino-like” climate state. For this study, we test this supposition by reconstructing EEP “excess CO2” and upwelling history for the past 6.5 million years using the alkenone-pCO2 methodology. Contrary to previous assertions, our results indicate that average temporal conditions in the EEP over the past ∼6.5 million years were characterized by substantial CO2 disequilibrium and high nutrient delivery to surface waters — characteristics that imply strong upwelling of deep waters. Upwelling appears most vigorous between ∼6.5 to 4.5 million years ago coinciding with high accumulation rates of biogenic material during the late Miocene – early Pliocene “biogenic bloom”.

The Asian monsoon has long been argued to be a product of the Himalaya–Tibetan Plateau, and simulation experiments have confirmed the key role of the Himalaya–Tibetan Plateau in transforming regional atmospheric and oceanic circulations. However, temporal constraints on the strengthening of the Asian monsoon inferred from foraminifer isotopic and faunal data and terrestrial climatic and ecological records are inconsistent with each other, which has obscured the tectonic-climatic linkage. In particular, discriminating the post-middle Miocene global cooling from the monsoon upwelling cooling is critical, but poorly understood due to the lack of adequate constraints for monsoonal upwelling. Here we present new middle to late Miocene biomarker-based reconstructions of sea-surface temperature (SST) for the western Arabian Sea. Our new SSTs capture a long-term ocean cooling since ca. 14.8 Ma and a major drop in SST in the period 11–10 Ma after which the SSTs reached similar values as the Holocene. The new SST record is consistent with planktonic foraminifer, siliceous biota, and geochemical tracer studies, suggestive of ocean cooling and high productivity associated with monsoonal upwelling. The 11–10 Ma ocean cooling is not clearly expressed in other tropical oceans, indicating that the ocean cooling in the western Arabian Sea is not a simple reflection of global cooling. We interpret the 11–10 Ma ocean cooling as representing the establishment of monsoonal upwelling in the western Arabian Sea, triggered by strong cyclonic activities as a result of the Neogene outward expansion of the Himalaya–Tibetan Plateau.

The early Eocene (56 to 48 million years ago) is inferred to have been the most recent time that Earth's atmospheric CO2 concentrations exceeded 1000 ppm. Global mean temperatures were also substantially warmer than present day. As such, study of early Eocene climate provides insight into how a super-warm Earth system behaves and offers an opportunity to evaluate climate models under conditions of high greenhouse gas forcing. The Deep Time Model Intercomparison Project (DeepMIP) is a systematic model-model and model-data intercomparison of three early Paleogne time slices: latest Paleocene, Paleocene-Eocene thermal maximum and early Eocene climatic optimum. A previous article outlined the model experimental design for climate model simulations. In this article, we outline the methodologies to be used for the compilation and analysis of climate proxy data, primarily proxies for temperature and CO2. This paper establishes the protocols for a concerted and coordinated effort to compile the climate proxy records across a wide geographic range. The resulting climate atlas will be used to constrain and evaluate climate models for the three selected time intervals, and provide insights into the mechanisms that control these warm climate states. We provide version 0.1 of this database, in anticipation that this will be expanded in subsequent publications.

Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are thought to be produced by as yet unknown bacteria on land, and their distribution in soils, peats, and lake sediments has been shown to correlate with mean annual air temperature (MAAT). Recently, an increasing number of studies have shown that in situ production of brGDGT in marine environments is likely. However, the influence of environmental factors on marine-derived brGDGT distributions is still unknown. In this study, we assessed the sources of brGDGTs preserved in a sediment core from the Chukchi Sea shelf using multiple brGDGT-based indices, including the branched and isoprenoid tetraethers (BIT) index, the ratio of IIIa/IIa, cyclization degree of branched tetraethers (CBT), and #rings indices, and discuss the influence of seawater temperature changes over the last 70 years on the distribution of brGDGT isomers. The low BIT and CBT values, high IIIa/IIa ratios, and significant correlations between different #rings indices suggest that these brGDGTs primarily have a marine source. With increasing sea surface temperatures (SSTs), the fractional abundances of 5-Me IIIa (IIIa5) showed an increased trend, while there was no obvious trend in 6-methyl IIIa (IIIa6). This finding indicates different behaviors of 5-Me and 6-Me isomers in marine-derived brGDGTs, similar to what has been observed in soils, peats and lakes. In addition, we found a significant correlation between IIIa5 and IIIa7 (a novel isomer of IIIa), indicating that they might share the same bacterial source and/or are controlled by the same environmental factors (e.g., temperature). Finally, the fractional abundances of IIIa5 and IIIa7 are significantly correlated with SST (r2 = 0.64 and 0.49, respectively), which suggests that marine-derived brGDGTs have the potential to reconstruct seawater temperature.

Thaumarchaeota, the major sources of marine glycerol dibiphytanyl glycerol tetraether lipids (GDGTs), are believed to fix the majority of their carbon directly from dissolved inorganic carbon (DIC). The δ13C values of GDGTs (δ13CGDGT) may be powerful tools for reconstructing variations in the ocean carbon cycle, including paleoproductivity and water mass circulation, if they can be related to values of δ13CDIC. To date, isotope measurements primarily are made on the C40 biphytane skeletons of GDGTs, rather than on complete tetraether structures. This approach erases information revealed by the isotopic heterogeneity of GDGTs within a sample and may impart an isotopic fractionation associated with the ether cleavage. To circumvent these issues, we present δ13C values for GDGTs from twelve recent sediments representing ten continental margin locations. Samples are purified by orthogonal dimensions of HPLC, followed by measurement of δ13C values by Spooling Wire Microcombustion (SWiM)-isotope ratio mass spectrometry (IRMS) with 1σ precision and accuracy of ±0.25‰. Using this approach, we confirm that GDGTs, generally around −19‰, are isotopically “heavy” compared to other marine lipids. However, measured δ13CGDGT values are inconsistent with predicted values based on the 13C content of DIC in the overlying water column and the previously-published biosynthetic isotope fractionation for a pure culture of an autotrophic marine thaumarchaeon. In some sediments, the isotopic composition of individual GDGTs differs, indicating multiple source inputs. The data appear to confirm that crenarchaeol primarily is a biomarker for Thaumarchaeota, but its δ13C values still cannot be explained solely by autotrophic carbon fixation. Overall the complexity of the results suggests that both organic carbon assimilation (ca. 25% of total carbon) and multiple source(s) of exogenous GDGTs (contributing generally

The TEX86 (tetraether index of 86 carbon atoms) sea surface temperature proxy has been increasingly applied in the reconstruction of Mesozoic and Cenozoic ocean temperatures. However, the archaeal lipids that compose TEX86 indices, glycerol dialkyl glycerol tetraethers (GDGTs), can derive from water column production, terrestrial sources, and/or within sediments. TEX86-sea surface temperature estimates can also be influenced by non-temperature factors, such as growth phase and nutrient levels. Here we show that the weighted average of cyclopentane moieties, known as the Ring Index (RI), can be used to determine if TEX86 temperature estimates are influenced by non-thermal factors and/or deviate from modern analogues. We demonstrate that RI and TEX86 indices from the published global core top data set and mesocosm cultures are significantly correlated, as predicted through the influence of temperature on lipid biochemistry. We further show that when RI and TEX86 indices in modern or ancient records deviate from the modern global TEX86-RI relationship, GDGT distributions are not solely controlled by environmental temperature and/or TEX86-based temperature reconstructions are questionable.

The fruits of Gardenia jasminoides Ellis are folk medicines in China and their major components are geniposide and water soluble pigment crocins. This study compared the chemical profiles and free radical scavenging activities of two Zhizi species from five provinces of China, including Jiangxi, Anhui, Hunan, Sichuan and Henan. The results showed that Jiangxi Zhizi contained higher levels of volatiles (71.84%), crocins (20.38 mg/g), geniposide (31.36 mg/g) and flavonoids (84.42 μg quercetin/mg) than four other Zhizi fruits; whereas Hunan Zhizi provided higher total phenolics (33.81 μg catechin/mg) and ABTS/DPPH radical scavenging activities. These findings implied that Jiangxi Zhizi would be suitable for extraction of gardenia yellow and geniposide, as well as preparation of essential oil. This information may provide valuable guidance for application of Zhizi fruits to biomedicine industry in China., Food science; Food engineering; Food technology; Food processing; Food analysis; Food composition; Food chemistry; Gardenia jasminoides; Volatiles; Active components; Different regions; Antioxidative activities.