Forests play a vital role in achieving the Sustainable Development Goals (SDGs), including SDG 13 (Climate Action) and SDG 15 (Life on Land), creating ecosystem values and reducing carbon emissions through conservation and sustainable management. These policy provisions are reflected in the international forums, such as the UNFCCC, CBD, UNCCD, the WCED Sustainability Report, Rio+20, and the SDG conference, which emphasise the importance of policy coherence for achieving sustainability and transformative policy solutions. This scholarship develops sustainability indicators and applies them in Bangladesh's community-based forest governance (CBFG) in order to assess policy performance. Applying a novel analytical framework and combining document analysis with expert opinions, the study examines whether policies and related instruments are coherent and consistent in delivering sustainability solutions within the CBFG policy area. This mixed-methods approach links overarching sectoral policies with policy instruments whilst examining sustainability performance based on policy goals, instruments, and implementation resources, thereby offering a comprehensive perspective of policy outputs and outcomes. This study captured mixed findings that highlight a potential gap in achieving sustainability policy solutions for CBFG. A lack of a robust institutional framework, faulty participatory monitoring and evaluation, inadequate funding options, and inefficient sectoral coordination hinder the sustainability of operations and limit the intended societal impact. Although policy instruments facilitate achieving policy goals, policy arrangements make the government organisation more powerful, rather than establishing an effective community-based governance mechanism. We proposed comprehensive policy recommendations for the Forest Department, in addition to the future research options.
Abstract Studying the salt tolerance mechanisms of rice under a single substrate has certain limitations. The salt tolerance strategies of rice may differ under different substrate conditions. This study established three substrate types by adjusting the proportions of laterite, peat moss, and river sand: S1 (high sand; low nutrient), S2 (medium sand; medium nutrient), and S3 (low sand; high nutrient). Compared with the respective fresh water control, the magnitude of dry weight reduction in each substrate gradually decreased (S1–S3), indicating that the salt stress was effectively alleviated. KEGG enrichment analysis of differentially expressed genes (DEGs) showed that Xiangliangyou900 may be more dependent on the remodeling of carbon metabolism pathway (compared to nitrogen metabolism) in S1, but the nitrogen metabolism pathway were more significant in S3. In S3, differential metabolites were significantly enriched in carbon and nitrogen metabolism pathways, but no such enrichment was found in S1, indicating that the S3 substrate, with its high nutrient and low river sand content, is more likely to trigger carbon and nitrogen metabolism remodeling. Under salt stress, the methylation level of C bases in the CHH type increased in S1 and decreased in S3. The methylation level of CHH-type C bases in the whole genome was more strongly correlated with the physicochemical parameters of the substrate (compared to CG and CHG types). This study speculated that rice may optimize its ability to adapt to salt stress by specifically regulating the methylation of CHH-type C bases to mediate gene expression. The results of this study help enrich the theoretical system of the rice salt stress response mechanism.
The Yunnan-Kweichow Plateau (YKP), a representative ecologically fragile zone, is subject to dual pressures from intensified climate change and anthropogenic activities. The specific mechanisms of how Net Ecosystem Productivity (NEP) responds to these changes remain unclear, whose relative contributions remain poorly quantified. This study conducts spatiotemporal quantification analysis of NEP dynamics and influencing factors in the YKP from 2001 to 2020, which integrated a linear regression, shifting center of gravity, Mann-Kendall trend test, partial correlation analysis, and random forest. The results showed an enhancement in NEP within the YKP (slope = 2.42 g C·m−2·yr−1, p < 0.05). Overall, climate change and anthropogenic activities contributed 1.86 g C·m−2·yr−1 and 0.76 g C·m−2·yr−1 to NEP variations, respectively. In terms of climate impact, temperature and precipitation are the main drivers affecting vegetation change, while radiation has the least influence. The importance of precipitation on NEP has been increasing by an upward trend, particularly in non-humid regions (slope = 0.31, p < 0.05) and grassland (slope = 0.45, p < 0.05). Besides, although the impact of climate change is dominant throughout the region, in areas affected by anthropogenic activities and climate change, the influence of anthropogenic activities is dominant and has a positive impact on the vegetation growth of YKP and NEP, especially in forest areas. The research elucidates the coupling mechanisms of how anthropogenic activities and climate change drive vegetation dynamics in the YKP region, providing key insights for boosting carbon sink capacity and promoting ecological sustainability.
ABSTRACT: Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs that have been implicated in mediating granulosa cell (GC) proliferation and apoptosis. CircRAB11A was found to have a significantly higher expression in normal follicles compared to atrophic follicles. In this study, we determined that the knockdown of circRAB11A resulted in the inhibition of proliferation and promotion of apoptosis in GCs of chicken. Moreover, circRAB11A was found to act as a sponge for miR-24-5p, both member RAS oncogene family (RAB11A) and epidermal growth factor receptor (EGFR) were revealed to be targets of miR-24-5p through a dual-luciferase reporter assay. RAB11A or EGFR promoted proliferation and suppressed apoptosis in GCs through the phosphatidylinositol-kinase (PI3K)/AKT or extracellular signal-regulated kinase (ERK)1/2 pathway. These findings suggest that circRAB11A may function as a competing endogenous RNA (ceRNA) by targeting the miR-24-5p/RAB11A and miR-24-5p/EGFR axes and activating the ERK1/2 and PI3K/AKT pathways, offering a potential avenue for exploring the mechanism of follicle development.
Abstract Plant Myeloblastosis (MYB) proteins function crucially roles upon variegated abiotic stresses. Nonetheless, their effects and mechanisms in rose (Rosa chinensis) are not fully clarified. In this study, we characterized the effects of rose RcMYB8 under salt and drought tolerances. For induction of the RcMYB8 expression, NaCl and drought stress treatment were adopted. Rose plants overexpressing RcMYB8 displayed enhanced tolerance to salinity and drought stress, while silencing RcMYB8 resulted in decreased tolerance, as evidenced by lowered intra-leaf electrolyte leakage and callose deposition, as well as photosynthetic sustainment under stressed conditions. Here, we further show that RcMYB8 binds similarly to the promoters of RcPR5/1 and RcP5C51 in vivo and in vitro. Inhibiting RcP5CS1 by virus-induced gene silencing led to decreased drought tolerance through the reactive oxygen species (ROS) homeostatic regulation. RcP5CS1-silenced plants showed an increase in ion leakage and reduce of proline content, together with the content of malondialdehyde (MDA) increased, lowered activities of Catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD). Our study highlights the transcriptional modulator role of RcMYB8 in drought and salinity tolerances, which bridges RcPR5/1 and RcP5CS1 by promoting ROS scavenging. Besides, it is probably applicable to the rose plant engineering for enhancing their abiotic stress tolerances. Graphical Abstract
<i>Zanthoxylum armatum</i> (<i>Z. armatum</i>) is an economic crop widely planted for both spice and medicinal purposes in Southwest China. Soil is a key environmental condition that affects seedling growth and development, and screening suitable soil types is of great significance for the large-scale cultivation of crops. This study designed growth experiments of <i>Z. armatum</i> seedlings in red soil (RS), yellow soil (YS), acidic purple soil (ACPS), alkaline purple soil (ALPS), and alluvial soil (AS) to screen for more suitable soil types. The growth traits of <i>Z. armatum</i> seedlings and the carbon (C), nitrogen (N), phosphorus (P), C:N:P stoichiometry, and non-structural carbohydrate (NSC) content of different organs were comparatively analyzed. The results showed that the morphological indexes of <i>Z. armatum</i> seedlings cultured in AS were better than those in the other four soils.AS and RS may be beneficial for the culture of <i>Z. armatum</i> seedlings due to higher nutrient levels in three organs. Two-factor ANOVA and PCA analysis showed that C, N, and P and their proportions would affect the uptake and distribution of NSC in various organs of <i>Z. armatum</i> seedlings. These results showed that soil types and plant organs significantly affected the accumulation and distribution of N, P, and NSC in <i>Z. armatum</i> seedlings. These results are conducive to screening soil types suitable for the growth and development of <i>Z. armatum</i> and provide data support for further large-scale cultivation of <i>Z. armatum</i> in suitable areas.
Idesia polycarpa Maxim is a native dioecious tree from East Asia cultivated for its fruits and as an ornamental plant throughout temperate regions. Given the economic potential, comparative studies on cultivated genotypes are of current interest. This study aims to discover the dynamic changes and potential functions of endogenous hormones in I. polycarpa, as well as the differences in endogenous hormone contents in different growth stages among different I. polycarpa provenances. We used High-Performance Liquid Chromatography (HPLC) to measure and compare the levels of abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellin A3 (GA3), and trans-Zeatin-riboside (tZR) in the leaves, flowers, and fruits of I. polycarpa from various provenances between April and October. Our findings indicated that changes in the ABA and GA3 content of plants from Jiyuan and Tokyo were minimal from April to October. However, the levels of these two hormones in Chengdu plants vary greatly at different stages of development. The peak of IAA content in the three plant materials occurred primarily during the early fruit stage and the fruit expansion stage. The concentration of tZR in the three plant materials varies greatly. Furthermore, we discovered that the contents of endogenous hormones in I. polycarpa leaves, flowers, and fruits from Chengdu provenances were slightly higher than those from Tokyo and Jiyuan provenances. The content of IAA was higher in male flowers than in female flowers, and the content of ABA, GA3, and tZR was higher in female flowers than in male flowers. According to the findings, the contents of these four endogenous hormones in I. polycarpa are primarily determined by the genetic characteristics of the trees and are less affected by cultivation conditions. The gender of I. polycarpa had a great influence on these four endogenous hormones. The findings of this study will provide a theoretical foundation and practical guidance for artificially regulating the flowering and fruiting of I. polycarpa.
AbstractNorthern leaf blight (NLB) (Exserohilum turcicum) is the most important among disease of maize in cold and humid areas in Nepal. Environmental factors, particularly temperature and relative humidity, have a significant impact on the development of diseases. With the objective to correlate weather parameters with disease development, the experiment was conducted using three distinct varieties: Popcorn Gorkha 3 (Susceptible check), Rampur Composite (Standard and Local Check), and Rampur Hybrid 10 (Resistant Check). Numerous disease-related variables, including disease incidence percent, percent disease index (PDI), area under the disease progress curve (AUDPC), and the number of infected leaves per sample plant (IL/S), were correlated with mean relative humidity (RH), maximum temperature, and lowest temperature. The disease severity raised from 22.22% to 88.89% in Pop Corn Gorkha 3, from 11.54% to 30.77% in Rampur Composite, and from 3.33% to 10% in Rampur Hybrid 10, when the minimum temperature dropped from 11.2°C to 6.2°C. Correlation coefficient and principal component analysis showed that minimum and maximum temperature were negatively correlated while RH was positively correlated. According to the coefficient of determination (R2), certain meteorological factors contributed 94%–99% to the severity of the condition. The crucial step in developing disease management methods is a systematic examination of the correlation between meteorological variables and disease severity.
Unequivocal evidence on the antagonistic effects of endophytic fungi associated with woody plants against insect herbivores has been documented in only a few cases so far. Experimental evidence of the significance of needle endophytes to coniferous trees has remained scant because it is difficult to obtain trees with needles free of endophytes that could be used as comparable controls for trees infected with endophytes. Previously we reported a new methodology to get Norway spruce (Picea abies (L.) Karst.) saplings without needle endophytes and to inoculate them with a needle endophyte Lophodermium piceae (Fuckel) Höhn. Here we describe the first trial where spruce saplings with and without needle endophytes were provided as substrate for insect larvae. We transferred larvae of two sawfly species, Neodiprion sertifer Geoffroy and Gilpina pallida Klug, to the seedlings. Even though the main host of these sawfly species is not Norway spruce, but Scots pine (Pinus sylvestris L.), they are also known to occasionally feed on spruce. In this experiment the larvae did not develop to pupae with the provided spruce substrate but consumed measurable amounts of needles. No significant difference was found between the extent of needles consumed by either of the two sawfly species in inoculated and uninoculated saplings.
The spatial distribution pattern of species diversity and its driving variables are essential to understanding how biodiversity will respond to the threat of future climatic instability. This study examines how the alpha and beta diversity indices vary along the elevation gradient and which factors are more responsible for arid and semi-arid plant diversity and community assembly. There were 121 species from 90 genera and 42 families found at elevations ranging from 1,200 to 2,600 m within the Ningxia Helan Mountain National Nature Reserve in China. These were primarily shrubs and herbs with characteristics adapted to extreme temperatures. The diversity of both the shrub layer and the herb layer was highest at mid-elevation, underscoring the importance of protecting mid-elevation ecosystems. Climatic distance and topographic distance were more influential than spatial distance in driving the species composition change of shrubs and herbs. In the herb layer, climatic, topographic, and spatial factors contributed more to community assembly than shrub communities. In this case, improving the environment in the community or introducing herbs could help the restoration of these places. These findings provide insight into biogeographic patterns, biodiversity growth mechanisms, and community formation processes. Moreover, it can improve projections of climate change within and across ecosystems and provide the scientific basis for the use and management of plant resources in arid and semi-arid regions.
Chemical hybridization and genic male sterility systems are two main methods of hybrid wheat production; however, complete sterility of female wheat plants cannot be guaranteed owing to the influence of the growth stage and weather. Consequently, hybrid wheat seeds are inevitably mixed with few parent seeds, especially female seeds. Therefore, seed purity is a key factor in the popularization of hybrid wheat. However, traditional seed purity detection and variety identification methods are time-consuming, laborious, and destructive. Therefore, to establish a non-destructive classification method for hybrid and female parent seeds, three hybrid wheat varieties (Jingmai 9, Jingmai 11, and Jingmai 183) and their parent seeds were sampled. The transmittance and reflectance spectra of all seeds were collected via hyperspectral imaging technology, and a classification model was established using partial least squares-discriminant analysis (PLS-DA) combined with various preprocessing methods. The transmittance spectrum significantly improved the classification of hybrids and female parents compared to that obtained using reflectance spectrum. Specifically, using transmittance spectrum combined with a characteristic wavelength-screening algorithm, the Detrend-CARS-PLS-DA model was established, and the accuracy rates in the testing sets of Jingmai 9, Jingmai 11, and Jingmai 183 were 95.69%, 98.25%, and 97.25%, respectively. In conclusion, transmittance hyperspectral imaging combined with a machine learning algorithm can effectively distinguish female parent seeds from hybrid seeds. These results provide a reference for rapid seed purity detection in the hybrid production process. Owing to the non-destructive and rapid nature of hyperspectral imaging, the detection of hybrid wheat seed purity can be improved by online sorting in the future.
Putri Alifa Kholil, Mochamad Arief Budihardjo, Fuad Muhammad
et al.
Pada tahun 2020, PT Pertamina (Persero) Fuel Terminal Parepare telah mendistribusikan BBM sebesar 498.270,317 kiloliter (KL). Proses distribusi BBM tersebut menghasilkan emisi dan limbah yang berpotensi berdampak pada lingkungan sekitar. Tujuan dari penelitian ini adalah menganalisis potensi dampak lingkungan dari proses distribusi BBM di PT Pertamina (Persero) Fuel Terminal Parepare dan mengetahui unit proses yang paling berdampak terhadap lingkungan menggunakan metode Life Cycle Assessment (LCA). LCA dilakukan dengan ruang lingkup gate-to-gate dimulai dari proses penerimaan BBM hingga pendistribusian BBM mengacu pada SNI ISO 14040:2016 dan SNI ISO 14044:2017. Perhitungan penilaian dampak dilakukan menggunakan software Microsoft Excel dengan metode CML IA Baseline dengan unit fungsi yang digunakan adalah 1 KL BBM. Kategori dampak potensi pemanasan global, potensi penipisan ozon, potensi hujan asam, dan potensi eutrofikasi dipilih berdasarkan relevansi dengan aktivitas perusahaan dan yang termasuk dampak kategori utama berdasarkan Peraturan Menteri Lingkungan Hidup dan Kehutanan Nomor 1 Tahun 2021 tentang Program Penilaian Peringkat Kinerja Perusahaan dan Pengelolaan Lingkungan Hidup. Hasil interpretasi menunjukkan seluruh dampak yang dikaji memiliki isu penting (hotspot) pada unit proses distribusi yang disebabkan oleh penggunaan listrik untuk pompa elmot dengan nilai karakterisasi untuk potensi pemanasan global sebesar 3,01 x 10-1 kg CO2 ek/KL, potensi penipisan ozon sebesar 8,79 x 10-9 kg CFC-11 ek/KL, potensi hujan asam sebesar 1,34 x 10-3 kg SO2 ek/KL, dan potensi eutrofikasi sebesar 1,65 x 10-3 kg PO4 ek/KL. Rekomendasi yang dapat diberikan adalah dengan melakukan efisiensi penggunaan listrik pompa atau dengan mengganti sumber energi listrik dari PLN menjadi energi terbarukan seperti menggunakan panel surya atau turbin angin.
ABSTRACT
In 2020, PT Pertamina (Persero) Fuel Terminal Parepare has distributed fuel amounting to 498,270,317 kiloliters (KL). The fuel distribution process produces emissions and waste that have the potential to have an impact on the surrounding environment. The purpose of this study is to analyze the potential environmental impact of the fuel distribution process at PT Pertamina (Persero) Fuel Terminal Parepare and find out the process units that have the most impact on the environment using the Life Cycle Assessment (LCA) method. LCA is carried out with a gate-to-gate scope starting from the process of receiving fuel to distributing fuel referring to SNI ISO 14040: 2016 and SNI ISO 14044: 2017. The calculation of impact assessment is carried out using Microsoft Excel software with the CML IA Baseline method with the function unit used is 1 KL BBM. Categories including global warming potential, ozone depletion potential, acid rain potential, and eutrophication potential were selected based on relevance to the company's activities and which included the impact of the main categories based on the Minister of Environment and Forestry Regulation No. 1 of 2021 concerning the Company Performance Rating Assessment Program and Environmental Management. The results of the interpretation showed that all the impacts studied had important issues (hotspots) on the distribution process unit caused by the use of electricity for elmot pumps with a characterization value of 3.01 x 10-1 kg of CO2 eq/KL, ozone depletion potential of 8.79 x 10 -9 kg CFC-11 eq/KL, acid rain potension of 1.34 x 10-3 kg SO2 eq/KL, and eutrophication potential of 1.65 x 10-3 kg PO4 eq/KL. Recommendations that can be given are to make efficiency of the use of pump electricity or by replacing the source of electrical energy from PLN to renewable energy such as using solar cells or wind turbines.
At present, the phenomenon of excessive pesticide residues in vegetables is prominent, causing widespread concern among all sectors of society. Excavate the influencing factors in the farmers themselves, government, market and society that affect vegetable farmers' green pesticide application behavior, clarify the influence mechanism of influencing factors on vegetable farmers' green pesticide application behavior. The study includes two parts: First, Grounded theory is used to construct a conceptual model that illustrates vegetable farmers' green pesticide application behavior. The second part applies the structural equation modeling to verify the research hypotheses, and reveals various factors in vegetable farmers' green pesticide application behavior (GB). The Results: Behavioral attitude (BA) and behavioral feedback perception (BP) are precursor variables that determine vegetable farmers' green pesticide application motivation (GM), and thus affect vegetable farmers' GB. Government supervision and regulation (GR), and market adjustment guidance (MG) are external factors that regulate the strength of the relationship between GM and GB. It is necessary to further strengthen the reference and normative role of society in vegetable farmers' GB, and provide a driving strategy for vegetable farmers' GB. Thus, it can better improve the quality of pesticide application and ensure vegetable safety.
Jenna M. Hartley, Kathryn T. Stevenson, M. Nils Peterson
et al.
Many of the most sweeping social movements throughout history have been youth-led, including those related to environmental challenges. Emerging research suggests youth can build environmental concern among parents via intergenerational learning, in some cases overcoming socio-ideological differences that normally stymie attempts at collective action. What has not been studied is the potential for youth to also influence adults outside their immediate families. This study based in North Carolina, USA, explores the potential of today's young people as environmental change-agents in their communities on the topic of marine debris. Specifically, this evaluation examines responses from voters and local officials after participating in youth-led civic engagement events. After engaging with a youth-led civic engagement event, voters, and local officials completed a retrospective pretest survey that asked questions about levels of marine debris concern and their likelihood of supporting a local marine debris ordinance. Young people encouraged both concern and policy support among both voters and officials, and that concern and policy support increased independently of whether adults were voters or officials, liberals or conservatives, or knew the students personally. Further, participation in the youth-led engagement event reduced political differences in marine debris concern. This study suggests youth can play a critical role addressing marine debris challenges by promoting support for marine debris management policy, and doing so across political barriers.
Following up on a thesis, this article re-examines the role of the landscape in two bodies of forestry documents dating from 2006 to 2018. Based on recent publications of the review Revue forestière française and forestry charters signed in the Provence-Alpes-Côte d’Azur (PACA) region, the definition and implementation of the notion of the landscape by forestry stakeholders is examined. This notion of the landscape is increasingly employed as a theoretical tool for analysing a territory and its evolution, however it does not seem to have acquired an operational dimension. References to landscape management, which were prevalent in the 1980s and 1990s, are becoming rarer, whereas landscape ecology, which is used in scientific research on forests, is hardly ever referred to in the more operational documents. In this sense, the documents studied appear to be consistent with the broader changes in the way the landscape is considered in scientific research and land use planning. The literature bears witness to gradual change over a long period of time which, from a methodological point of view, justifies going back into the “field" or more precisely re-examining the research "object" at regular intervals.
Most streptococci are commensals, pathogens, or opportunistic pathogens for humans and animals. Therefore, it is important for streptococci to adapt to the various challenging environments of the host during the processes of infection or colonization, as well as to in vitro conditions for transmission. Stringent response (SR) is a special class of adaptive response induced by the signal molecules (p)ppGpp, which regulate several physiological aspects, such as long-term persistence, virulence, biofilm formation, and quorum sensing in bacteria. To understand the roles of SR in streptococci, the current mini-review gives a general overview on: (1) (p)ppGpp synthetases in the genus of Streptococcus, (2) the effects of (p)ppGpp on the physiological phenotypes, persistence, and pathogenicity of streptococci, (3) the transcriptional regulation induced by (p)ppGpp in streptococci, and (4) the link between (p)ppGpp and another nutrient regulatory protein CodY in streptococci.
Yadeta Teshome, Birhanu Biazin, Kebede Wolka
et al.
Abstract Unpredictability by local farmers, insufficiency and seasonality of rainfall have severely affected productivity of rain-fed agriculture in Cheleleka watershed. Thus, irrigated agriculture has a paramount role in lifesaving and insuring food security. Mismanagement of irrigation water influences agricultural productivity and efficiency of water uses. This study aimed to assess performance and potential of traditional surface irrigation schemes and to survey conflicts resulting from irrigation water use and management. Three major rivers in Cheleleka watershed (Wesha, Worka and Wodesa) where traditional irrigation has been widely practiced were selected purposively. The irrigable areas of each river were identified and categorized into upper, middle and lower parts based on its related location in the watershed. The soil samples, infiltration rate, long time meteorology, conveyance efficiency, irrigable areas and discharge at diversion points were analyzed. In addition, 49 households in irrigable areas of the three rivers were interviewed and three focus group discussions were held. About 0.16 and 0.14 m3/s of discharge were recorded in irrigation areas of the middle Wodesa and upper Worka rivers, respectively. The conveyance efficiency of the traditional surface irrigation canals at middle Wodesa and upper Wesha and Worka was less than 50%. The general potentials of surface irrigation water across the three perennial rivers were greater than 23 million cubic meters per year. The moisture stored in root zone or readily available water in existing farmers’ practices was found far beyond the carrying capacity of the soils, especially in middle Wodesa and upper Wesha and Worka areas. Performances of the traditional surface irrigation schemes are very low and had aggravated irrigation water losses and contributed to crop water scarcity and conflicts. The results also showed that farmers in the upper parts of the area and close to the diversion points excessively irrigate the cropland, whereas those far away and in lower watersheds of each river receive irrigation water insufficiently and irregularly. Even though there was irrigation management system/committee, the set principle was not respected.
Quality of service (QoS) is an important performance indicator for Web applications and bandwidth is a key factor affecting QoS. Current methods use network protocols or ports to schedule bandwidth, which require tedious manual configurations or modifications of the underlying network. Some applications use dynamic ports and the traditional port-based bandwidth control methods cannot deal with them. A new QoS control method based on local bandwidth scheduling is proposed, which can schedule bandwidth at application level in a user-transparent way and it does not require tedious manual configurations. Experimental results indicate that the new method can effectively improve the QoS for applications, and it can be easily integrated into current Web applications without the need to modify the underlying network.
Francisc Vasile DULF, Mihaela Ligia UNGURESAN, Dan Cristian VODNAR
et al.
The unsaponifiable lipid fraction of plant-based foods is a potential source of bioactive components such as phytosterols, triterpenoids, carotenoids, tocopherols and various hydrocarbons. The free and esterified sterol concentrations in four Romanian edible oils (corn germ, wheat germ, sweet almond and grape seed oil) were determined, including individual values for β-sitosterol, campesterol, stigmasterol, Δ5-avenasterol, sitostanol, campestanol, and cholesterol. Free and esterified sterols were separated by solid-phase extraction (SPE), saponified, and analyzed as trimethylsilyl ether derivatives using gas-chromatography (GC) with flame ionization detector (FID). Differences in total sterol content and the proportion of esterified (ES) and free sterols (FS) were evident for studied oil samples. In general, β-sitosterol was the most prevalent phytosterol, ranging in concentration from 158.3 mg/100 g in grape seed oil to 478.5 mg/100 g in corn germ oil. Only in these two vegetable oil, we identified trace amount of cholesterol (<3 mg/100g). The total sterol concentrations ranged from 199.9 mg/100g (sweet almond oil) to 745.2 mg/100 g (corn germ oil). In corn germ and wheat germ oil, the dominant form of sterols was the esterified one (60.7% ES and 55.6% ES, respectively, of total sterols). This study consolidates the view that vegetable oils are good natural sources of phytosterols. The analyses of these components provide rich information about the identity and quality of vegetable oils. The corn germ and wheat germ oils proved to be the richest sources in phytosterols, being recommended as functional oils.<br />