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Plant protection products derived from plant material are proposed to be a sustainable alternative to conventional synthetic chemical pesticides. This study determines the efficacy of a commercially available bioinsecticide based on garlic (Allium sativum L.; Asparagales: Amaryllidaceae) extract against vine weevil (Otiorhynchus sulcatus F.; Coleoptera: Curculionidae) eggs and larvae in contact, fumigation and a combination of contact and fumigation bioassays under laboratory conditions. Results showed that garlic significantly reduced egg hatch rate compared to the control group when applied as a fumigant. Similarly, the egg hatch rate was reduced compared to the control group when garlic was applied as combined contact and fumigant applications. No effect was observed when the garlic product was applied as a contact application. The bioinsecticide significantly reduced larval survival when either contact or fumigant applications were used. A combined contact and fumigant effect was shown also when vine weevil eggs were exposed to the bioinsecticide for 30 days in plastic containers containing growing media. The number of larvae recovered after this period was significantly reduced compared to the control group. This study demonstrates the potential of garlic-based bioinsecticides, such as Pitcher GR, for vine weevil control. Further studies are, however, needed to determine the efficacy of such bioinsecticides under field conditions and investigate how these products can be most effectively used as a part of a wider vine weevil integrated pest management program. [ABSTRACT FROM AUTHOR]

Aims Enteric viruses are recognized as a major concern in health care and in the food sector in Canada. Novel clean-label strategies for controlling enteric viruses are sought in the food industry. In this study, we examined the antiviral potential of plant extracts and essential oils on murine norovirus 1 (MNV-1), hepatitis A virus (HAV), and herpes simplex virus 1 (HSV-1). Methods and results Inactivation of the viruses by grape seed, blueberry, green tea, and cranberry extracts and by rosemary and thyme essential oils was measured using plaque formation assay. Concentrations ranging from 50 to 200   000 ppm with a contact time of 90 min were tested. Grape seed extract at 10 000 ppm was the most effective (P < 0.05) at reducing MNV-1 and HAV infectious titers, respectively, by 2.85 ± 0.44 log10 and 1.94 ± 0.17 log10. HSV-1 titer was reduced by 3.81 ± 0.40 log10 at 1000 ppm grape seed extract. Conclusions Among the plant products tested, grape seed extract was found the most effective at reducing the infectious titers of MNV-1, HAV, and HSV. [ABSTRACT FROM AUTHOR]

Traditional healers are often practiced in rural areas owing to cultural beliefs and are known to provide various forms of healthcare and home remedies. Patients in the Mediterranean region rely on traditional medicine to cure a variety of health concerns, like skin burns. This study was conducted to identify the various practices used by traditional healers for treating skin burns. The survey was conducted in 18 Arab countries, including Syria, Iraq, Jordan, Saudi Arabia, Egypt, United Arab Emirates, Algeria, Bahrain, Palestine, Kuwait, Oman, Qatar, Lebanon, Yemen, Tunisia, Oman, Morocco, and Sudan. Between September 2020 and July 2021, an online questionnaire was administered to 7530 participants from 12 Asian and 5 African countries. The survey was designed to gather information from common medicinal plant users and herbalists on their practices as specialists in using various herbal and medicinal plant products for diagnosis and treatment. Among the participants, 2260 had a scientific background in plant application, and the study included one phytotherapeutic professional. The crude-extraction technique was favored, by Arabic folk, for plant preparation over the maceration and decoction method. Olive oil was the most commonly used product among participants as an anti-inflammation and for scar reduction. Aloe vera , olive oil, sesame, Ceretonia siliqua , lavender, potato, cucumber, shea butter, and wheat flour are used as crude drugs to reduce pain because of their analgesic and cooling effects. The present study is the first database of medicinal plants with burn-healing properties conducted in Arab countries. These plants can be employed in the search for new bioactive substances through pharmacochemical investigations, as well as in the development of new formulations containing a combination of these plants. [ABSTRACT FROM AUTHOR]

The article discusses the need for reforms in pesticide regulatory practices to protect pollinators. It clarifies that the focus of the article is on global pesticide regulations, with a specific emphasis on the Environmental Protection Agency (EPA) in the United States. The authors suggest that the US should adopt the evaluation of plant protection products as formulations, similar to the European Union. They also highlight the importance of post-approval monitoring and testing the effects of pesticides on diverse pollinator species. The article calls for a broad conversation and cooperation among stakeholders to protect pollinators. [Extracted from the article]

This article responds to a previous article proposing reforms to pesticide regulations to protect pollinators. The authors, who are part of a risk assessment authority, aim to provide clarifications about the regulatory framework in Europe. They emphasize that both the active substance and formulated products undergo thorough risk assessments to ensure their safety. They also mention efforts to include non-Apis bees in risk assessments and the development of test methods for bumble bees and solitary bees. The authors welcome enhancements to regulatory testing and invite stakeholders to participate in discussions to improve risk assessment and management. [Extracted from the article]

Soybean meal (SBM) is a high-protein plant product commonly used as a primary protein source in pig diets. However, its price has been steadily increasing. Concurrently researchers were prompted to search for cost-effective, high-yield protein sources. In the earlier studies palm kernel meal (PKM), distillers dried grains solubles (DDGS), and rapeseed meal (RSM) were potentially used as substitutes for SBM. Still, no study exists on conducting a comparative analysis of replacing soybean meal with various plant extracts. Therefore, we aimed to analyze whether replacing SBM with various plant extracts could reveal comparable effects on growth performance, nutrient digestibility, and meat quality in finishing pigs. For 10 wk, n = 200 [(Yorkshire × Landrace) × Duroc] finishing pigs [body weight (BW) = 57.07 ± 3.18 kg] were assigned to one of five dietary treatments. The test treatments were control (CON) corn-SBM-based diet, and the CON diet replaced with 10% of PKM, lupin Kernel (LK), RSM, and DDGS, respectively. Each treatment has 10 replicates with 4 (2 barrows and 2 gilts) pigs/pen. The dietary treatments were as follows control (CON), a corn-SBM-based diet; and the SBM diet replaced with 10% of each PKM, Lupin Kernel (LK), RSM, and DDGS. The partial replacement of SBM with various plants reveals neither significant nor adverse effects on the overall performance in finishing pigs. In summary, we concluded that partially replacing SBM with various plant sources would serve as a better option for small farm owners to save their feed costs. [ABSTRACT FROM AUTHOR]

The objectives of this study were to study the effect of adding plant extracted saponin (PES) as phytochemical feed additive on in vitro accumulative gas production kinetics and methane (CH4) emission of blend pelleted feed products in ruminant system. Four levels of PES (0, 1, 2, 3%) were added to canola meal and pea mixtures with two different ratios (CMP1: 50:50; CMP2: 70:30) which were used to make Prairie blend pellet feed products. The accumulative gas production kinetics and CH4 were determined using in vitro systems. Ruminal fluid for in vitro studies was obtained from rumen fistulated lactation dairy cows. The experimental design was a randomized complete block design with the PES level as a fixed effect and in vitro run with fistulated animals as a random effect. The data were analyzed using Mixed Model Procedure of SAS. Polynomial contract was used to determine linear and quadratic relationship. The results showed that adding PES did not significantly affect the asymptotic production (a) with an average of 104.06 ± 12.38 (SD) mL/g DM, the gas production fractional rate (c) with an average of 1.00 ± 0.90 %/h, the average production at one-half of asymptotic production (AP) with an average 11.26 ± 0.87 mL and lag time with an average of 2.08 ± 0.81 h. As to CH4 emission at different incubation times, the result showed that at short incubation times (2 h, 4 h, 12 h), adding PES showed numerically reduced CH4 from 277 to 1.08 mL/g (at 2 h) and 4.39 to 1.59 mL/g (at 4 h). With increasing PES level, CH4 was significantly linearly reduced (P = 0.019) from 8.31 to 6.30 mL/g at 12h incubation time. At long incubation (24 h), adding PES did not have significant impact on CH4 . In conclusion, adding PES at the studied levels to Prairie blend pellet feed products did not significantly affect accumulative gas production kinetics but it had a high potential to decrease CH4 emission at short incubation times. [ABSTRACT FROM AUTHOR]

The objectives of this study were to study the effect of adding plant extracted hydrolysable tanning (HT) and saponin (S) combination as a combined phytochemical feed additive (HTS) on in vitro accumulative gas production kinetics and methane (CH4 ) emission of blend pelleted feed products in ruminant systems. Four combination levels [0 (control), 1.5 (1% HT + 0.5% S), 3 (2% HT + 1%S), 4.5 (3% HT + 1.5% S)] were added to canola meal and pea mixtures with two different ratios (CMP1: 50:50; CMP2: 70:30) which were used to make Prairie blend pellet feed products. The accumulative gas production kinetics and CH4 were determined using in vitro systems. The ruminal fluid was obtained from rumen fistulated lactation dairy cows. The experimental design was a randomized complete block design with the HTS level as a fixed effect and in vitro run with fistulated animals as a random effect. The data were analyzed using SAS Mixed Procedure. Polynomial contract was used to determine linear and quadratic relationship. The results showed that adding HTS level linearly reduced asymptotic production a) from 110.5 to 82.7 mL/g DM (P = 0.043) and average production at one-half of asymptotic production (AP) from 11.9 to 9.5 mL (P = 0.069) without significantly affecting gas production fractional rate (c, %/h) with an average of 0.58 ± 0.49 %/h and lag time with an average of 1.95 ± 0.50 h. As to CH4 emission at different incubation times, the result showed that at short incubation times (2 h, 4 h, 12 h), adding HTS had numerically reduced methane emission (CH4) from 2.77 to 0.98 mL/g (at 2 h) and 4.39 to 1.38 mL/g (at 4 h). with increasing HTS level, CH4 was significantly quadratically reduced (P = 0.028) at 12 h incubation time from 8.31 to 5.76 mL/g. After long incubation (24 h), adding HTS did not have significant impact on CH4 . In conclusion, adding HTS to prairie blend pellet feed products significantly affected gas production kinetics (the asymptotic production and average production at one-half of asymptotic production). Adding HTS had an increased potential to decrease CH4 emission at short incubation times. [ABSTRACT FROM AUTHOR]

Luteolin, an abundant flavonoid in the leaves of Capsicum annuum, has antioxidant activity and is, thus, a key chemical for promoting plant residue utilization, especially for the development of healthcare products. We assessed the inhibitory effect of luteolin and its glycosides on osteoclastic differentiation in human cells and found that the differentiation was effectively inhibited at noncytotoxic concentrations. We also screened 47 varieties of C. annuum for the accumulation of luteolin and apigenin to determine the prevalence of luteolin in diverse cultivars and identify varieties with high and/or selective luteolin production. The glycosides of luteolin and apigenin were found in all the tested varieties, with luteolin predominant over apigenin in most varieties. The identification and characterization of highly productive varieties of C. annuum is expected to be beneficial for the effective development of useful luteolin-based products from plant residues. Flavonoid luteolin and glycosides inhibited osteoclast differentiation in human cell, and 47 varieties of Capsicum annuum were characterized about their productivity of flavonoids in leaf. [ABSTRACT FROM AUTHOR]

Iron (Fe) is one of the essential micronutrients required by both plants and animals. In humans, Fe deficiency causes anemia, the most prevalent nutritional disorder. Most people rely on plant-based foods as their major Fe source, but plants are a poor source of dietary Fe. Therefore, there is a critical need to better understand the mechanisms involved in the uptake and trafficking of Fe and how plants adapt to Fe deficiency. Fe participates in key cellular functions such as photosynthesis and respiration. Perturbations of Fe uptake, transport, or storage affect plant growth as well as crop yield and plant product quality. Excess Fe has toxic effects due to its high redox activity. Plants, therefore, tightly regulate Fe uptake, distribution, and allocation. Here, we review the regulatory mechanisms involved at the transcriptional and post-translational levels that are critical to prevent Fe uptake except when plants experience Fe deficiency. We discuss the key regulatory network of basic helix–loop–helix (bHLH) transcription factors, including FIT, subgroup Ib, subgroup IVc, and URI (bHLH121), crucial for regulating Fe uptake in Arabidopsis thaliana. Furthermore, we describe the regulators of these transcription factors that either activate or inhibit their function, ensuring optimal Fe uptake that is essential for plant growth. [ABSTRACT FROM AUTHOR]

Although Aloe vera and Moringa oleifera plant extracts are known for their methane inhibition their potential has not been fully exploited in the feeding system of animals due to inconsistent results and loss of efficacy over time. Encapsulation of the plant extract and its bioactive compounds in particular with an inert material will assist to prolong the shelf life of the plant extract. Alginate is a good encapsulant (or a wall material) for encapsulation of plant extracts due to its biocompatibility and low density, among other factors. This study first evaluated A. vera and M. oleifera plant extracts encapsulated with alginate or aligante and chitosan in terms of microscopic morphological characteristics and particle density, and thereafter quantified the potential of encapsulated A. vera and M. oleifera plant extracts as dietary additive to inhibit in vitro methane production from Eragrostis curvula hay. An electron microscope scanning of the freeze-dried alginate or alginate encapsulated plant extracts of A. vera and M. oleifera revealed morphologically spongy and skin-like appearance while for chitosan a scatter particle distribution of different sizes with irregular shape were revealed (Fig. 1). A change in particle density was recorded for the encapsulated plant extracts products compared with the non-encapsulated product due to the inclusion of alginate or alginatechitosan wall material. The particle density for the encapsulated products was ranging between 4.94 g/10mL (recorded in alginate) to 8.71 g/10mL (recorded in chitosan). During the in vitro gas production study, inclusion of both the encapsulated and non-encapsulated plant extract of A. vera or M. oleifera additives significantly (P < 0.05) reduced methane emission compared with the control group. No adverse effect was observed due to the inclusion of the wall materials in terms of in vitro organic matter digestibility and total gas production (Fig. 2). However, the encapsulated A. vera plant extracts had resulted in a greater methane inhibition of 30.72% (for alginate-extract encapsulated) and 23.09% (for alginate-extract-chitosan encapsulated) against 17.55% reduction recorded for the raw plant extracts. Similarly, the encapsulated M. oleifera plant extracts inhibited methane by 30.02% (alginate-extract encapsulated) and 30.48% (alginate-extract-chitosan encapsulated) against 19.4% recorded for in M. oleifera raw plant extracts. It is revealed that alginate and/or chitosan also had methane reducing effect when tested as additives without the two plant extracts (Table 1,2). However, the differences in particle densities of the micro-particles from the encapsulated and nonencapsulated plant extract additives did not affect their methane inhibition (Fig. 3). Thus, the wall materials (alginate or alginate-chitosan) generally improved the in vitro methane inhibition of encapsulated plant extracts mainly by promoting the inhibition of methane without adverse effect on organic matter digestibility of substrates. [ABSTRACT FROM AUTHOR]

Microbial fermentation platforms offer a cost-effective and sustainable alternative to plant cultivation and chemical synthesis for the production of many plant-derived pharmaceuticals. Plant alkaloids, particularly benzylisoquinoline alkaloids and monoterpene indole alkaloids, and recently cannabinoids have become attractive targets for microbial biosynthesis owing to their medicinal importance. Recent advances in the discovery of pathway components, together with the application of synthetic biology tools, have facilitated the assembly of plant alkaloid and cannabinoid pathways in the microbial hosts Escherichia coli and Saccharomyces cerevisiae. This review highlights key aspects of these pathways in the framework of overcoming bottlenecks in microbial production to further improve end-product titers. We discuss the opportunities that emerge from a better understanding of the pathway components by further study of the plant, and strategies for generation of new and advanced medicinal compounds. [ABSTRACT FROM AUTHOR]

Isoprenoids constitute the largest class of plant natural products and have diverse biological functions including in plant growth and development. In potato (Solanum tuberosum), the regulatory mechanism underlying the biosynthesis of isoprenoids through the mevalonate pathway is unclear. We assessed the role of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) homologs in potato development and in the metabolic regulation of isoprenoid biosynthesis by generating transgenic lines with down-regulated expression (RNAi- hmgr) or overexpression (OE) of one (StHMGR1 or StHMGR3) or two genes, HMGR and farnesyl diphosphate synthase (FPS ; StHMGR1/StFPS1 or StHMGR3/StFPS1). Levels of sterols, steroidal glycoalkaloids (SGAs), and plastidial isoprenoids were elevated in the OE- HMGR1 , OE- HMGR1/FPS1 , and OE- HMGR3/FPS1 lines, and these plants exhibited early flowering, increased stem height, increased biomass, and increased total tuber weight. However, OE- HMGR3 lines showed dwarfism and had the highest sterol amounts, but without an increase in SGA levels, supporting a rate-limiting role for HMGR3 in the accumulation of sterols. Potato RNAi- hmgr lines showed inhibited growth and reduced cytosolic isoprenoid levels. We also determined the relative importance of transcriptional control at regulatory points of isoprenoid precursor biosynthesis by assessing gene–metabolite correlations. These findings provide novel insights into specific end-products of the sterol pathway and could be important for crop yield and bioenergy crops. [ABSTRACT FROM AUTHOR]

l -arabinofuranose is a ubiquitous component of the cell wall and various natural products in plants, where it is synthesized from cytosolic UDP-arabinopyranose (UDP-Ara p). The biosynthetic machinery long remained enigmatic in terms of responsible enzymes and subcellular localization. With the discovery of UDP-Ara p mutase in plant cytosol, the demonstration of its role in cell-wall arabinose incorporation and the identification of UDP-arabinofuranose transporters in the Golgi membrane, it is clear that the cytosolic UDP-Ara p mutases are the key enzymes converting UDP-Ara p to UDP-arabinofuranose for cell wall and natural product biosynthesis. This has recently been confirmed by several genotype/phenotype studies. In contrast to the solid evidence pertaining to UDP-Ara p mutase function in vivo, the molecular features, including enzymatic mechanism and oligomeric state, remain unknown. However, these enzymes belong to the small family of proteins originally identified as reversibly glycosylated polypeptides (RGPs), which has been studied for >20 years. Here, we review the UDP-Ara p mutase and RGP literature together, to summarize and systemize reported molecular characteristics and relations to other proteins. [ABSTRACT FROM AUTHOR]

Microorganisms are intentionally added at different stages of the food and feed chain (food or feed additive, novel food or plant protection product) and are subjected to regulation and safety assessment by the European Food Safety Authority. Safety evaluation is based on application dossiers for market authorisation to the European Commission. The qualified presumption of safety (QPS) concept was developed in 20032 to provide a harmonised generic safety pre-appraisal of the above microorganisms. Unambiguously defined biological taxonomic units (TUs) are assessed for their body of knowledge, their safety and their end use. Identified safety concerns for a certain TU can be, where reasonable in number and not universally present, reflected as 'qualifications.' Strains belonging to TUs having QPS status may benefit of a fast track evaluation. The lowest TU for which the QPS status is granted is the species level for bacteria and yeasts and the family for viruses. The QPS concept is also applicable to genetically modified microorganisms used for production purposes. Based on the current body of knowledge and/or the ambiguous taxonomic position, some TUs, such as filamentous fungi, bacteriophages, Enterococcus faecium, Escherichia coli, Streptomyces spp. and Oomycetes, are not considered liable for QPS status. [ABSTRACT FROM AUTHOR]

Background: Ayurveda, the traditional Indian therapeutic system, involves herbs and spices as drug ingredients and a kind of food intake regulation. The health and curative aspects of plant products are often ascribed to their antimicrobial and antioxidant activities (AA). However, it seems somewhat possible to correlate the AA of herbal extracts or plant isolates with their phenolic contents (PC). Objective: Indian researchers have carried out some tests for the determination of AA and PC of plant products that are worth mentioning. Methods: Among the herbal analysis techniques, the important contributions of Indians and people of Indian origin in this field include the remarkable separation of phenolic compounds, including the use of reversed-phase columns, on-line HPLC, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay to effectively screen and identify antioxidant compounds from herbal extracts, and other chromatographic, spectrographic, and spectroscopic techniques, in the analysis of complex biological matrices. Results: The aim of this paper is to present an overview of such arguments with reference to herbal drugs and food intake regulation for specific ailments. Conclusions: The lack of uniformity in the use of test protocols for antioxidant assays (particularly using the DPPH free radical) and differences in in vitro mechanisms of antiradical activity and in vivo metabolism of polyphenols have been the issues associated with these experiments that have been raised by researchers in the period from 2000 onward. [ABSTRACT FROM AUTHOR]

Glycosylation of small molecules is critical for numerous biological processes in plants, including hormone homeostasis, neutralization of xenobiotics, and synthesis and storage of specialized metabolites. Glycosylation of plant natural products is usually performed by uridine diphosphate-dependent glycosyltransferases (UGTs). Triterpene glycosides (saponins) are a large family of plant natural products that determine important agronomic traits such as disease resistance and flavor and have numerous pharmaceutical applications. Most characterized plant natural product UGTs are glucosyltransferases, and little is known about enzymes that add other sugars. Here we report the discovery and characterization of AsAAT1 (UGT99D1), which is required for biosynthesis of the antifungal saponin avenacin A-1 in oat (Avena strigosa). This enzyme adds l -Ara to the triterpene scaffold at the C-3 position, a modification critical for disease resistance. The only previously reported plant natural product arabinosyltransferase is a flavonoid arabinosyltransferase from Arabidopsis (Arabidopsis thaliana). We show that AsAAT1 has high specificity for UDP-β- l -arabinopyranose, identify two amino acids required for sugar donor specificity, and through targeted mutagenesis convert AsAAT1 into a glucosyltransferase. We further identify a second arabinosyltransferase potentially implicated in the biosynthesis of saponins that determine bitterness in soybean (Glycine max). Our investigations suggest independent evolution of UDP-Ara sugar donor specificity in arabinosyltransferases in monocots and eudicots. [ABSTRACT FROM AUTHOR]

Objectives: The goal of this study was to determine several beneficial and antinutritional compounds in the commercial products of some protein-rich crops. Materials and Methods: Samples of faba bean (Vicia faba), lupin (Lupinus angustifolius), rapeseed press cake (Brassica rapa/napus subsp. Oleifera), flaxseed (Linum usitatissimum), oil hemp seed (Cannabis sativa), buckwheat (Fagopyrum esculentum), and quinoa (Chenopodium quinoa) were purchased from the grocery stores and from the producers. The phytochemicals were analyzed using various validated methods. Results: Rape seed press cake contained the highest contents of phenolics. The highest contents of proanthocyanidins were found in faba bean (470 ± 14 mg/100g DW). Secoisolariciresinol-diglucoside content in the flaxseeds was 138 ± 32 mg/100 g DW and the lignanamide content of hemp seeds was 77 ± 22 mg/100 g DW. The content of phytic acid in rapeseed cake, hemp seed and flaxseed samples was 3.9 ± 0.1, 3.5 ± 0.2, and 1.9 ± 0 g/100 g DW, respectively. Rape seed cake contained glucosinolates 2.08 ± 0.74 umol/g DW and faba bean contained vicine and convicine 0.77 ± 0.11 and 0.42 ± 0.02 g/100 g DW, respectively. Quinoa contained saponins 557 mg/100 g DW and after abrasive milling/pearling the content was 36 mg/100 g DW. Generally, the phytochemicals were concentrated in the outer shell of the seed. Inhibitory activities against proteolytic enzymes, trypsin and α-chymotrypsin, varied among the samples analyzed. Highest activity was found in buckwheat samples, whereas lupin and rapeseed press cake had no inhibitory activity against tested enzymes. Conclusions: This paper presented new findings on the contents of phytochemicals in various underused plant protein sources. [ABSTRACT FROM AUTHOR]

Aims The potential of Dicranopteris linearis leaves' extract and its bioactive components were investigated for the first time for its disrupting ability against Staphylococcus aureus biofilms. Methods and Results The leaves of D. linearis were subjected to sonication-assisted extraction using hexane (HEX), dichloromethane, ethyl acetate and methanol (MeOH). It was found that only the MeOH fraction exhibited antimicrobial activity using broth microdilution assay; while all four fractions do not exhibit biofilm inhibition activity against S. aureus ATCC 6538P, S. aureus ATCC 43300, S. aureus ATCC 33591 and S. aureus ATCC 29213 using crystal violet assay. Among the four fractions tested, only the HEX fraction showed biofilm disrupting ability, with 60-90% disruption activity at 5 mg ml−1 against all four S. aureus strains tested. Bioassay-guided purification of the active fraction has led to the isolation of α-tocopherol. α-Tocopherol does not affect the cells within the biofilms but instead affects the biofilm matrix in order to disrupt S. aureus biofilms. Conclusions α-Tocopherol was identified to be the bioactive component of D. linearis with disruption activity against S. aureus biofilm matrix. Significance and Impact of the Study The use of α-tocopherol as a biofilm disruptive agent might potentially be useful to treat biofilm-associated infections in the future. [ABSTRACT FROM AUTHOR]

Plants produce diverse specialized metabolites (SMs), but the genes responsible for their production and regulation remain largely unknown, hindering efforts to tap plant pharmacopeia. Given that genes comprising SM pathways exhibit environmentally dependent coregulation, we hypothesized that genes within a SM pathway would form tight associations (modules) with each other in coexpression networks, facilitating their identification. To evaluate this hypothesis, we used 10 global coexpression data sets, each a meta-analysis of hundreds to thousands of experiments, across eight plant species to identify hundreds of coexpressed gene modules per data set. In support of our hypothesis, 15.3 to 52.6% of modules contained two or more known SM biosynthetic genes, and module genes were enriched in SM functions. Moreover, modules recovered many experimentally validated SM pathways, including all six known to form biosynthetic gene clusters (BGCs). In contrast, bioinformatically predicted BGCs (i.e. those lacking an associated metabolite) were no more coexpressed than the null distribution for neighboring genes. These results suggest that most predicted plant BGCs are not genuine SM pathways and argue that BGCs are not a hallmark of plant specialized metabolism. We submit that global gene coexpression is a rich, largely untapped resource for discovering the genetic basis and architecture of plant natural products. [ABSTRACT FROM AUTHOR]

The qualitative and quantitative analysis of the major bioactive components in traditional Chinese medicines (TCM) and their preparations is essential to evaluate their quality. However, the scarcity and high cost of chemical reference standards are common obstacles for quantitative analysis, especially for determining multicomponents. In this study, an effective and sensitive qualitative method to identify flavonol glycosides in Ginkgo leaves (Ginkgo Folium), and their preparations have been developed. Meanwhile, a simple, convenient and reproducible method for the quantitative analysis of multicomponents by a single marker (QAMS) has been established to simultaneously determine the major flavonol glycosides in Ginkgo leaves and their preparations. Among the 15 favonol glycosides that were found, 7 major flavonol glycosides with high contents were simultaneously determined by the QAMS and traditional external standard method (TES). Rutin was selected as the single marker, and the quantitative analysis was performed on a TSK gel ODS-100V C18 column using a gradient system of acetonitrile and water, with a variable wavelength detector (265 nm) within 50 min. The method validation was conducted, and the linearity was excellent (r² > 0.9993) with accuracy and precision within the required limits. The F-test (P > 0.05) indicated that the QAMS and TES method have no statistically significant difference. [ABSTRACT FROM AUTHOR]

Rhizogenic Agrobacterium biovar 1 strains have been found to cause extensive root proliferation on hydroponically grown Cucurbitaceae and Solanaceae crops, resulting in substantial economic losses. As these agrobacteria live under similar ecological conditions, infecting a limited number of crops, it may be hypothesized that genetic and phenotypic variation among such strains is relatively low. In this study we assessed the phenotypic diversity as well as the phylogenetic and evolutionary relationships of several rhizogenic Agrobacterium biovar 1 strains from cucurbit and solanaceous crops. A collection of 41 isolates was subjected to a number of phenotypic assays and characterized by MLSA targeting four housekeeping genes (16S rRNA gene, recA, rpoB and trpE) and two loci from the root-inducing Ri-plasmid (part of rolB and virD2). Besides phenotypic variation, remarkable genotypic diversity was observed, especially for some chromosomal loci such as trpE. In contrast, genetic diversity was lower for the plasmid-borne loci, indicating that the studied chromosomal housekeeping genes and Ri-plasmid-borne loci might not exhibit the same evolutionary history. Furthermore, phylogenetic and network analyses and several recombination tests suggested that recombination could be contributing in some extent to the evolutionary dynamics of rhizogenic Agrobacterium populations. Finally, a genomospecies-level identification analysis revealed that at least four genomospecies may occur on cucurbit and tomato crops (G1, G3, G8 and G9). Together, this studygives a first glimpse at the genetic and phenotypic diversity within this economically important plant pathogenic bacterium. [ABSTRACT FROM AUTHOR]

Timber production and prices are determined by the global demand for forest products, and the capability of producers frommanycountries to growand harvest trees, transform them into products and export. The Global Forest Products Model (GFPM) simulates howthis global demand and supply of multiple products among manycountries determines prices and attendant consumption, production and trade. This paper documents the methods, data and computer software of the GFPMmodel, followed byexamples of applications to forecasting, and for policyanalysis of the consequences of offset payments for carbon sequestration in forests. [ABSTRACT FROM AUTHOR]

The cholesterol lowering effects of plant sterols and stanols are a well-established complementary means by which to reduce blood cholesterol concentrations. The average reduction in LDL cholesterol concentrations is approximately -10% following a 28-day supplementation protocol. There is very little known regarding what, if any, effect plant sterols and stanols have on other cardiometabolic risk factors such as blood pressure and endothelial function. Here we review the available literature on this topic and attempt to draw conclusions regarding any benefit or risk for blood pressure and endothelial function linked to plant sterol and stanol supplementation. Generally there has been very little work focusing on changes in blood pressure or endothelial function following plant sterol or stanol intervention, but these factors have been measured in some cases as secondary outcomes. Overall, there is little evidence to support either positive or negative effects of plant sterol or stanol supplementation of blood pressure and the data surrounding endothelial function is quite inconclusive. This area of research would benefit from well controlled mechanistic studies in animals and primary interventions in humans which focus on ambulatory blood pressure, central blood pressure and endothelial function. [ABSTRACT FROM AUTHOR]

Despite the abundance of clinical trial data demonstrating the cholesterol-lowering action of plant sterol supplementation, substantial variability in efficacy exists in responsiveness across individuals. The goal of this review is to examine factors responsible for this heterogeneity in responsiveness of blood cholesterol levels to dietary plant sterols. Although initially thought to be due to random noise in the data, demonstrated consistency in degree of responsiveness in the context of controlled feeding designs from person to person suggests that other systematic drivers are responsible. Genetic explanations explaining this phenomenon appear to be gaining momentum. Particularly, single nucleotide polymorphisms within the genes coding for CYP7A1 and ApoE, as well as possibly other genes including ABCG5 and ABCG8, exist as predictors of whether LDL-C levels will decrease or even increase subsequent to plant sterol administration. In summary, nutrigenetic differences across genes associated with cholesterol trafficking pathways may be important in predicting how well any given individual will respond to dietary interventions. It is anticipated that eventually genetic tests will be developed that can guide health care professionals to optimize dietary strategies for health optimization. [ABSTRACT FROM AUTHOR]

The recent IMPROVE-IT trial clearly showed that lowering serum low-density lipoprotein cholesterol (LDL-C) concentrations via inhibiting intestinal cholesterol absorption through ezetimibe effectively lowered the number of new cardiovascular disease (CVD) events. This supports the use of other (dietary) interventions that lower serum LDL-C concentrations via comparable mechanisms such as described for plant sterol and stanol ester enriched functional foods. Therefore it is tempting to suggest that these compounds may have the same effects on CVD outcome, as described for ezetimibe in the IMPROVE-IT trial. This has however not been proven so far. A possible advantage of plant sterol and stanol ester enriched foods over ezetimibe--a typical single-target drug--is that these dietary compounds act on multiple targets, since they not only lower serum LDL-C concentrations, but also lower serum triacylglycerol (TAG) concentrations in subjects with elevated serum TAG concentrations. In addition, they might influence the functioning of our immune system via a changed activity of the regulatory T-cells. This combination of effects makes these compounds highly attractive to decrease CVD risk. [ABSTRACT FROM AUTHOR]

Cholesterol-lowering properties of plant sterols were reported approximately six decades ago. However, over the past couple of decades we have learnt more about other cardiovascular benefits of regular consumption of plant sterols and/or plant stanols. In particular a series of animal studies has consistently reported that dietary plant sterols and/or plant stanols or their fatty acid esters can reduce atherogenesis to a different extent in different animal models. Such effects may be mediated not only through reductions in LDL cholesterol levels, but also through other mechanisms including anti-inflammatory effects. In this manuscript, various animal models including mice, rabbits, hamsters, and others which have been used to establish cardiovascular benefits of plant sterols are discussed. [ABSTRACT FROM AUTHOR]

All fruits, vegetables, grains and other plant materials contain small amounts of plant sterols, which are essential for the function of the biological membranes in living cells. The average human consumption of plant sterols has been estimated to be about 150-350 mg/day and trace amounts of stanols (which are defined as saturated sterols such as sitostanol), but this number varies regionally and is higher for vegetarians. When consumed in the diet, plant sterols reduce the levels of serum cholesterol. In 1995 the first functional food product, Benecol spread (enriched in plant stanol fatty acid esters), was developed by Raisio and marketed, first in Finland and then globally. Since then many other functional food products have been developed and are now available globally. In addition to stanol esters, other functional food products contain plant sterol esters and/or free (unesterified) plant sterols and stanols. In essentially all of the current functional foods that are enriched in sterols and stanols, the feedstock from which the sterols and stanols are obtained is either tall oil (a byproduct/coproduct of the pulping of pine wood) or vegetable oil deodorizer distillate (a byproduct/coproduct of the refining of vegetable oils). [ABSTRACT FROM AUTHOR]

A total of 320 finishing pigs (PlC 327 x1050; initially 98 kg) were used to determine the effects of adding Zn to diets containing ractopamine HC1 (RAC) on muscle fiber type distribution, fresh chop color, and cooked meat characteristics. Dietary treatments were fed for approximately 35 d and consisted of a corn-soybean meal-based negative control (CON), a positive control diet with 10 mg/kg of RAC (RAC+), and the RAC+ diet plus 75, 150, or 225 mg/kg added Zn from either ZnO or Availa-Zn. Loins randomly selected from each treatment (n = 20) were evaluated using contrasts: CON vs. RAC+, interaction of Zn level xsource, Zn level linear and quadratic polynomials, and Zn source. There were no Zn source effects or Zn source xlevel interactions through out the study (P> 0.10). Pigs fed RAC+ had increased (P <0.02) percentage type lixand a tendency for increased (P = 0.10) percent type JIB muscle fibers. Increasing added Zn decreased (linear, P = 0.01) percentage type hA and tended to increase (P = 0.09) IIIX muscle fibers. On d 1, 2, 3,4, and 5 of display, pork chops from pigs fed the RAC+ treatment had greater (P < 0.03) L* values compared to the CON. On d 0 and 3 of display, increasing added Zn tended to decrease (quadratic, P = 0.10) L* values and decreased (quadratic, P < 0.03) L* values on d 1, 2,4, and 5. Pigs fed RAC+ had decreased (P < 0.05) a* values on d 1 and 4 of display and tended to have decreased (P <0.10) a* values on d 0 and 2 compared to CON pork chops. Pork chops from the RAC+ treatment had a tendency for increased (P < 0.08) oxymyoglobin percentage compared to CON pork chops on d 1, 2,4, and 5. On d 0, as dietary Zn increased in RAC+ diets, there was a decrease (linear, P < 0.01) in the formation of pork chop surface oxymyoglobin percentage. Metmyoglobin reducing ability (MRA) of pork chops on d 5 was decreased in the RAC+ group. Chops from pigs fed added Zn had increased (quadratic, P < 0.03) MRA on d 3 and 5 of the display period. There was a trend for increased (linear, P = 0.07) cooking loss with increasing Zn in RAC diets and treatments did not affect tenderness as measured by Wamer-Bratzler shear force (P> 0.07). In conclusion, RAC+ diets produced chops that were lighter and less red but maintained a greater percentage of surface oxymyoglobin throughout a 5-d simulated retail display. Ractopamine reduced MRA at the end of the display period, but supplementing Zn to RAC diets restored MRA to near CON treatment levels at the end of the display period. [ABSTRACT FROM AUTHOR]

Background. Targeting host-cell pathways to increase the potency of nucleoside/nucleotide analog reverse transcriptase inhibitors (NRTIs) is an important strategy for clinical investigation. Resveratrol is a natural product that inhibits cellular ribonucleotide reductase, prolonging the S phase of the cell cycle and preferentially lowering dATP levels.Methods. We performed in vitro evaluation of resveratrol on the antiviral activity of adenosine analog tenofovir (TFV) against sensitive and drug-resistant human immunodeficiency virus type 1 (HIV-1), from subtypes B and C, in primary cells.Results. Resveratrol enhanced the antiviral activity of TFV by up to 10-fold and restored susceptibility of TFV-resistant viruses. Resveratrol prevented wild-type HIV-1 from developing phenotypic resistance to TFV. Notably, resveratrol enhanced TFV activity against sensitive and resistant HIV-1 from both subtypes B and C.Conclusions. Prolonged wide-scale use of thymidine analogs in the setting of viral failure has limited the efficacy of second-line NRTI-based regimens in Africa. Moreover, the extensive use of ddI and d4T has led to high frequencies of the K65R mutation, further compromising TFV efficacy. In light of increasing resistance to commonly used NRTIs in global HIV treatment programs, targeting nucleoside biosynthesis with resveratrol, or derivatives with improved bioavailabilities, is a potential strategy to maintain, enhance, and restore susceptibility of commonly used NRTIs. [ABSTRACT FROM PUBLISHER]

Searching for bioactive compounds from natural resources such as plant materials has become a focus for study. Several models, such as animal (biofluid, organ and tissue) and cellular (several kinds of cell lines), have traditionally been used for this purpose. As a fast, economic and effective way to identify or predict bioactive compounds in complex matrices, biochromatography has developed rapidly during the past years. Combing the properties of traditional chromatography and biomaterials, biochromatographic analysis possesses features of simultaneous screening, separation and structural identification for active compounds in a complex matrix. According to the process, biochromatography can be divided into offline and online approaches. For offline bioextraction, the biomaterials are used as the extraction phase and followed by routine chromatographic analysis. For online biochromatography, the biomaterials are directly used as the stationary phase for chromatographic analysis. This paper reviews the applications of offline bioextraction followed by chromatographic analysis and online biochromatography, including molecular, cell membrane and cell, and artificial biomembrane chromatography in the screening or predicting active compounds from natural sources. [ABSTRACT FROM AUTHOR]

Objective Mango ( Mangifera indica L.) stem bark extract ( MSBE) is a natural product with biological properties and mangiferin is the major component. This paper reported the evaluation of the protective effects of MSBE and mangiferin against the toxicity induced in HepG2 cells by tert-butyl hydroperoxide or amiodarone. Method Nuclear morphology, cell viability, intracellular calcium concentration and reactive oxygen species ( ROS) production were measured by using a high-content screening multiparametric assay. Key findings MSBE and mangiferin produced no toxicity below 500 mg/ml doses. A marked recovery in cell viability, which was reduced by the toxicants, was observed in cells pre-exposed to MSBE or mangiferin at 5-100 mg/ml doses. We also explored the possible interaction of both products over P-glycoprotein ( P-gp). MSBE and mangiferin above 100 mg/ml inhibited the activity of P-gp in HepG2 cells. Conclusions MSBE and mangiferin showed cytoprotective effects of against oxidative damage and mitochondrial toxicity induced by xenobiotics to human hepatic cells but it seemed that other constituents of the extract could contribute to MSBE protective properties. In addition, the drug efflux should be taken into account because of the inhibition of the P-gp function observed in those cells exposed to both natural products. [ABSTRACT FROM AUTHOR]

The article presents a study that aims at synthesizing bioactive epidermal patterning factor-like protein 5 (sEPFL5) and determining its structure and bioactivity. It shows that the stomatal development in the epidermis of the flowering plant Arabidopsis thaliana is positively and negatively regulated by EPFLs which are cysteine-rich peptides. It informs that sEPFL5 promotes differentiation of stomatal lineage cells to pavement cells.

Spice and medicinal plants grown under water deficiency conditions reveal much higher concentrations of relevant natural products compared with identical plants of the same species cultivated with an ample water supply. For the first time, experimental data related to this well-known phenomenon have been collected and a putative mechanistic concept considering general plant physiological and biochemical aspects is presented. Water shortage induces drought stress-related metabolic responses and, due to stomatal closure, the uptake of CO2 decreases significantly. As a result, the consumption of reduction equivalents (NADPH + H+) for CO2 fixation via the Calvin cycle declines considerably, generating a large oxidative stress and an oversupply of reduction equivalents. As a consequence, metabolic processes are shifted towards biosynthetic activities that consume reduction equivalents. Accordingly, the synthesis of reduced compounds, such as isoprenoids, phenols or alkaloids, is enhanced. [ABSTRACT FROM AUTHOR]

The article discusses a study which demonstrated a pretreatment method of purifying feed samples from toxic metabolite ochratoxin A based on an immunoaffinity chromatography (IAC) procedure extraction from which the eluates were determined by liquid chromatography-flourescence detection. It offers information on the results of the study through a discussion of the IAC column, extraction and clean up procedure, and the application of method to real feed samples.

Operon-like gene clusters are an emerging phenomenon in the field of plant natural products. The genes encoding some of the best-characterized plant secondary metabolite biosynthetic pathways are scattered across plant genomes. However, an increasing number of gene clusters encoding the synthesis of diverse natural products have recently been reported in plant genomes. These clusters have arisen through the neo-functionalization and relocation of existing genes within the genome, and not by horizontal gene transfer from microbes. The reasons for clustering are not yet clear, although this form of gene organization is likely to facilitate co-inheritance and co-regulation. Oats (Avena spp) synthesize antimicrobial triterpenoids (avenacins) that provide protection against disease. The synthesis of these compounds is encoded by a gene cluster. Here we show that a module of three adjacent genes within the wider biosynthetic gene cluster is required for avenacin acylation. Through the characterization of these genes and their encoded proteins we present a model of the subcellular organization of triterpenoid biosynthesis. [ABSTRACT FROM AUTHOR]

Objectives: To describe risk factors for clustering of anemia among mothers and children in Indonesia. Methods: An anemia cluster was defined as hemoglobin <12 g/dl in the mother and <11 g/dl in the youngest child, aged 6–59 months. Results: Anemia clustering occurred in 4907 (18.3%) of 26 809 urban families and 12 756 (15.5%) of 82 291 rural families. Maternal overweight/obesity, older child age, consumption of fortified milk by the child, use of iodized salt, vitamin A supplementation, paternal smoking and greater expenditure on animal and plant source foods were associated with lower odds of anemia clustering. Older maternal age, maternal underweight, &geq;2 children in the family and >4 individuals eating from the same kitchen were associated with greater odds of anemia clustering. Conclusion: Fortified milk, iodized salt, vitamin A supplementation and greater expenditure on plant and animal foods are among modifiable risk factors associated with lower risk of anemia clustering in Indonesia. [ABSTRACT FROM PUBLISHER]

Triterpene saponins are a diverse group of biologically functional products in plants. Saponins usually are glycosylated, which gives rise to a wide diversity of structures and functions. In the group A saponins of soybean (Glycine max), differences in the terminal sugar species located on the C-22 sugar chain of an aglycone core, soyasapogenol A, were observed to be under genetic control. Further genetic analyses and mapping revealed that the structural diversity of glycosylation was determined by multiple alleles of a single locus, Sg-1 , and led to identification of a UDP-sugar–dependent glycosyltransferase gene (Glyma07g38460). Although their sequences are highly similar and both glycosylate the nonacetylated saponin A0-αg, the Sg-1a allele encodes the xylosyltransferase UGT73F4, whereas Sg-1b encodes the glucosyltransferase UGT73F2. Homology models and site-directed mutagenesis analyses showed that Ser-138 in Sg-1a and Gly-138 in Sg-1b proteins are crucial residues for their respective sugar donor specificities. Transgenic complementation tests followed by recombinant enzyme assays in vitro demonstrated that sg-10 is a loss-of-function allele of Sg-1. Considering that the terminal sugar species in the group A saponins are responsible for the strong bitterness and astringent aftertastes of soybean seeds, our findings herein provide useful tools to improve commercial properties of soybean products. [ABSTRACT FROM AUTHOR]

S elenomonas ruminantium strains were isolated from sheep rumen, and their significance for fiber digestion was evaluated. Based on the phylogenetic classification, two clades of S . ruminantium (clades I and II) were proposed. Clade II is newly found, as it comprised only new isolates that were phylogenetically distant from the type strain, while all of the known isolates were grouped in the major clade I. More than half of clade I isolates displayed CMCase activity with no relation to the degree of bacterial adherence to fibers. Although none of the isolates digested fiber in monoculture, they stimulated fiber digestion when co-cultured with F ibrobacter succinogenes, and there was an enhancement of propionate production. The extent of such synergy depended on the clade, with higher digestion observed by co-culture of clade I isolates with F . succinogenes than by co-culture with clade II isolates. Quantitative PCR analysis showed that bacterial abundance in the rumen was higher for clade I than for clade II. These results suggest that S . ruminantium, in particular the major clade I, is involved in rumen fiber digestion by cooperating with F . succinogenes. [ABSTRACT FROM AUTHOR]

Plants are important sources of food and plant products are essential for modern human life. Plants are increasingly gaining importance as drug and fuel resources, bioremediation tools and as tools for recombinant technology. Considering these applications, database infrastructure for plant model systems deserves much more attention. Study of plant biological pathways, the interconnection between these pathways and plant systems biology on the whole has in general lagged behind human systems biology. In this article we review plant pathway databases and the resources that are currently available. We lay out trends and challenges in the ongoing efforts to integrate plant pathway databases and the applications of database integration. We also discuss how progress in non-plant communities can serve as an example for the improvement of the plant pathway database landscape and thereby allow quantitative modeling of plant biosystems. We propose Good Database Practice as a possible model for collaboration and to ease future integration efforts. [ABSTRACT FROM PUBLISHER]

The article discusses research which examines the characterization and production of a mannosylerythritol lipid (MEL) B glycolipid biosurfactant from sugarcane juice using Ustilago scitaminea NBRC 32730. The study showed the capability of NBRC 32730 to produce a mono-acetylated and di-acylated MEL, MEL-B from sucrose as sole carbon source. It revealed that supplementation with organic and inorganic nitrogen sources enhanced the production yield.

The Swede midge, Contarinia nasturtii Kieffer (Diptera: Cecidomyiidae), a common insect pest in Europe, is a newly invasive pest in North America that constitutes a major threat to cruciferous vegetable and field crops. Since its first identification in Ontario, Canada, in 2000, it has rapidly spread to 65 counties in the provinces of Ontario and Quebec and has recently been found in canola (one of two cultivars of rapeseed, Brassica napus L. and Brassica campestris L.) in the central Prairie region where the majority of Canada's 6.5 million ha (16 million acres) of canola is grown. The first detection of Swede midge in the United States was in 2004 in New York cabbage (Brassica oleracea L.), but it has now been found in four additional states. Here, we review the biology of Swede midge, its host plant range, distribution, economic impact, pest status, and management strategies. We provide insight into this insect's future potential to become an endemic pest of brassica crops in North America. We also proposed research needed to develop tactics for handling this invasive pest in brassica crops. [ABSTRACT FROM AUTHOR]

A low-cost procedure was designed for easy and rapid response-on-demand production of fresh wine yeast for local wine-making. The pilot plant produced fresh yeast culture concentrate with good microbial quality and excellent oenological properties from four selected wine yeasts. The best production yields were obtained using 2% sugar beet molasses and a working culture volume of less than 60% of the fermenter capacity. The yeast yield using 2% sugar grape juice was low and had poor cell viability after freeze storage, although the resulting yeast would be directly available for use in the winery. The performance of these yeasts in commercial wineries was excellent; they dominated must fermentation and improved its kinetics, as well as improving the physicochemical parameters and the organoleptic quality of red and white wines. [ABSTRACT FROM AUTHOR]

While exogenous toxic compounds such as herbicides are thought to be sequestered into vacuoles in the form of glutathione (GSH) conjugates, little is understood about natural plant products conjugated with GSH. To identify natural products conjugated with GSH in plants, metabolites in the Arabidopsis γ-glutamyl transpeptidase (ggt) 4 knockout mutants that are blocked in the degradation of GSH conjugates in the vacuole were compared with those in wild-type plants. Among the metabolites identified, one was confirmed to be the 12-oxo-phytodienoic acid (OPDA)–GSH conjugate, indicating that OPDA, a precursor of jasmonic acid (JA), is transported into the vacuole as a GSH conjugate. [ABSTRACT FROM AUTHOR]

Aims: To evaluate the antiviral activity of Bignoniaceae species occurring in the state of Minas Gerais, Brazil. Methods and Results: Ethanol extracts of different anatomical parts of bignoniaceous plant species have been evaluated in vitro against human herpesvirus type 1 (HSV-1), vaccinia virus (VACV) and murine encephalomyocarditis virus (EMCV) by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. A total of 34 extracts from 18 plant species selected according to ethnopharmacological and taxonomic criteria were screened. Fifteen of the 34 extracts (44·1%) have disclosed antiviral activity against one or more of the viruses assayed with EC50 values in the range of 23·2 ± 2·5-422·7 ± 10·9 μg ml−1. Conclusions: Twelve of the 34 extracts (35·3%) might be considered promising sources of antiviral natural products, as they have shown EC50 ≤ 100 μg ml−1. The present screening discloses the high potential of the Bignoniaceae family as source of antiviral agents. Significance and Impact of the Study: Active extracts were identified and deserve bioguided studies for the isolation of antiviral compounds and studies on mechanism of action. [ABSTRACT FROM AUTHOR]

The soil-dwelling bacterium Bacillus subtilis differentiates into distinct subpopulations of specialized cells that coexist within highly structured communities. The coordination and interplay between these cell types requires extensive extracellular communication driven mostly by sensing self-generated secreted signals. These extracellular signals activate a set of sensor kinases, which respond by phosphorylating three major regulatory proteins, Spo0A, DegU and ComA. Each phosphorylated regulator triggers a specific differentiation program while at the same time repressing other differentiation programs. This allows a cell to differentiate in response to a specific cue, even in the presence of other, possibly conflicting, signals. The sensor kinases involved respond to an eclectic group of extracellular signals, such as quorum-sensing molecules, natural products, temperature, pH or scarcity of nutrients. This article reviews the cascades of cell differentiation pathways that are triggered by sensing extracellular signals. We also present a tentative developmental model in which the diverse cell types sequentially differentiate to achieve the proper development of the bacterial community. [ABSTRACT FROM AUTHOR]

Saponins, an important group of bioactive plant natural products, are glycosides of triterpenoid or steroidal aglycones (sapogenins). Saponins possess many biological activities, including conferring potential health benefits for humans. However, most of the steps specific for the biosynthesis of triterpene saponins remain uncharacterized at the molecular level. Here, we use comprehensive gene expression clustering analysis to identify candidate genes involved in the elaboration, hydroxylation, and glycosylation of the triterpene skeleton in the model legume Medicago truncatula. Four candidate uridine diphosphate glycosyltransferases were expressed in Escherichia coli , one of which (UGT73F3) showed specificity for multiple sapogenins and was confirmed to glucosylate hederagenin at the C28 position. Genetic loss-of-function studies in M. truncatula confirmed the in vivo function of UGT73F3 in saponin biosynthesis. This report provides a basis for future studies to define genetically the roles of multiple cytochromes P450 and glycosyltransferases in triterpene saponin biosynthesis in Medicago. [ABSTRACT FROM AUTHOR]

Flavonols are important ultraviolet light protectants in many plants and contribute substantially to the quality and health- promoting effects of fruits and derived plant products. To study the regulation of flavonol synthesis in fruit, we isolated and characterized the grapevine (Vitis vinifera 'Shiraz') R2R3-MYB transcription factor VvMYBF1. Transient reporter assays established VvMYBF1 to be a specific activator of flavonol synthasel (VvFLS1) and several other promoters of grapevine and Arabidopsis (Arabidopsis thaliana) genes involved in flavonol synthesis. Expression of VvMYBF1 in the Arabidopsis mutant myb12 resulted in complementation of its flavonol-deficient phenotype and confirmed the function of VvMYBF1 as a transcriptional regulator of flavonol synthesis. Transcript analysis of VvMYBF1 throughout grape berry development revealed its expression during flowering and in skins of ripening berries, which correlates with the accumulation of flavonols and expression of VvFLST1. In addition to its developmental regulation, VvMYBF1 expression was light inducible, implicating VvMYBF1 in the control of VvFLS1 transcription. Sequence analysis of VvMYBF1 and VVFLS1 indicated conserved putative light regulatory units in promoters of both genes from different cultivars. By analysis of the VvMYBF1 amino acid sequence, we identified the previously described SG7 domain and an additional sequence motif conserved in several plant MYB factors. The described motifs have been used to identify MYB transcription factors from other plant species putatively involved in the regulation of flavonol biosynthesis. To our knowledge, this is the first functional characterization of a light-inducible MYB transcription factor controlling flavonol synthesis in fruit. [ABSTRACT FROM AUTHOR]