Search

Development of an efficient system for callus induction on different explants of fenugreek. Comparing phenolic, antioxidant and antimicrobial activities of seed and calli of different fenugreek explants. Fenugreek is a well-known medicinal plant for pharmaceutical and nutraceutical properties. For callus induction, three explants were used viz. hypocotyl, root, and cotyledons. The explants were cultured on MS medium supplemented with 2, 4-D, NAA and TDZ in different concentrations (0.5-6 mg/L). Antioxidant activity using DPPH and Folin-ciocalteu assays, and antimicrobial activity of calli and seed extracts were evaluated. Friable callus was successfully induced on all explants and by all PGRs except 2, 4-D which failed to stimulate callus formation on root explant. Root segment was the better explants in callus induction with maximum fresh weight 5.29 g with TDZ at 2 mg/L and highest callus index was 4.3 with TDZ at 0.5 mg/L. Hypocotyl callus showed the highest phenolic content (246.9 mg GAE/g DW) compared to root callus (243.5 mg GAE/g DW), seed (176.2 mg GAE/g DW) and then cotyledons callus (64.9 mg GAE/g DW) with the lowest value. On the other hand, seed exhibited 44.3% antioxidant activity compared to 34.7%, 24.3% and 16.7% recorded by cotyledons, hypocotyl, and root calli, respectively. Regarding antimicrobial activity of studied fenugreek extracts, hypocotyl callus exhibited the maximum zone of inhibition recorded (19 mm) against E. coli. Callus of fenugreek showed potential biological activities over seed-extract.

Various research works recognized highly biological activities of sorghum vegetative portions which indicated the presence of bioactive compounds in their extracts. Considering environmental effects on the accumulation of secondary metabolites, this work aims to evaluate the antibacterial activity of sorghum usingin vitroinduced leaves as source for extract.In vitroshoot explants of sorghum used subcultured on Murashige and Skoog medium (MS) supplemented with 6-Benzyl adenine (BA) or Indole-3-butyric acid (IBA) at different concentrations (0.0–2.0 mg/L). The leaves inducedin vitrowere collected dried then macerated in ethanol for 4 hours. Phytochemical composition of the sorghum leaves extract was assessed using standard procedures. The crude extracts were evaluated for antibacterial activity using the agar well diffusion method. The significantly (P>0.05) maximum shoot length (5.7 cm) and the number of leaves (7.9 leaves) were obtained on MS medium supplemented with 2.0 mg/L IBA. The phytochemical composition of the leaves extract showed the presence of bioactive constituents including alkaloids, flavonoids, tannins, saponins and steroids and triterpenes. All the concentrations of the sorghum leaves extract showed variable antimicrobial activity against the studied bacteria strains with the strongest inhibitory effect reported (19.0 mm) againstB. subtilisat the concentration of 100 mg/L. Our findings demonstrated that thein vitroleaves extract of sorghum possess a remarkable antibacterial activity. More research is needed on the characterization of bioactive ingredients ofin vitroinduced sorghum plants and their biological activities.

Callus induction was established on internodal and leaf explants of Grewia tenax cultured on Murashige and Skoog (MS) solid medium supplied with indole-3-butyric acid (IBA), 2,4-dichlorophenoxyacet...

A Gram-staining-negative, strictly aerobic, non-motile strain, SYSUP0001T, was isolated from tubers of Gastrodia elata Blume. The 16S rRNA gene sequence result indicated that SYSUP0001T represents a member of the genus Sphingomonas , with the highest sequence similarity (97.7 %) to the type strain of Sphingomonas ginsengisoli . SYSUP0001T grew at 14–37 °C and pH 6–8, with optimum growth at 28 °C and pH 7. Tolerance to NaCl was up to 3 % (w/v) with optimum growth in the absence of NaCl. The respiratory quinone was Q-10. The major fatty acids were C18 : 1ω7c, Summed feature 3 (C16 : 1ω7c/C16 : 1ω6c), and C16 : 0. The polar lipids were diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), sphingoglycolipid (SGL), phosphatidylcholine (PC) and four unidentified polar lipids (L). The DNA G+C content was 67.5 %. The average nucleotide identity (ANI) values between SYSUP0001T and closely related members of the genus Sphingomonas were below the cut-off level (95–96 %) for species delineation. On the basis of the phenotypic, phylogenetic and chemotaxonomic characterizations, SYSUP0001T represents a novel species of the genus Sphingomonas , for which the name Sphingomonasmesophila sp. nov. is proposed. The type strain is SYSUP0001T (=KCTC 62179 T=CGMCC 1.16462T).

A Gram-stain-negative, strictly aerobic, non-motile strain, SYSUP0003T, was isolated from tubers of Gastrodia elata Blume. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SYSUP0003T belonged to the genus Paracoccus , with the highest sequence similarity to the type strain of Paracoccus sediminis (97.5 %). Strain SYSUP0003T grew at pH 6.0–8.0 and 4–30 °C with optimum growth at pH 7.0 and 28 °C. Strain SYSUP0003T could tolerate up to 1 % (w/v) NaCl and grew optimally in the absence of NaCl. The isoprenoid quinone of strain SYSUP0003T was Q-10. The major fatty acids were C18 : 0, C16 : 0, C10 : 0 3-OH and summed feature 7. The polar lipids were diphosphatidylglycerol (DPG), aminophospholipids (AL), phosphatidylglycerol (PG), phosphatidylcholine (PC) and four unidentified polar lipids (L). The genome size was 3 204 685 bp, with a DNA G+C content of 69.7 mol%. The average nucleotide identity values between strain SYSUP0003T and P. sediminis DSM 26170T (ANIm 84.2 %, ANIb 75.6 %), Paracoccus solventivorans DSM 6637T (ANIm 84.5 %, ANIb 76.9 %) and Paracoccus alkenifer DSM 11593T (ANIm 84.3 %, ANIb 77.3 %) were below the cut-off level (95–96 %) for species delineation. Based on phenotypic, chemotaxonomic and molecular characterizations, strain SYSUP0003T represents a novel species of the genus Paracoccus , for which the name Paracoccus endophyticus sp. nov. is proposed. The type strain is SYSUP0003T (=KCTC 62180T=CGMCC 1.16545T).

Grewia tenax (Forssk.) Fiori is a multi-purpose shrub species that is threatened in its natural environment because of extensive fruit collection and seed dormancy. We induced direct multiple shoots of G. tenax from the cotyledonary node, shoot, and stem node explants. The explants were cultured on a Murashige and Skoog (MS) solid medium supplemented with up to 4.0 mg/l of benzyladenine (BA), kinetin (Kin), isopentanyl adenine (2iP), or thidiazuron (TDZ). The highest number of shoots (4.8 ± 0.4) was obtained when 2-shoot explants regenerated on the primary medium containing 3.0 mg/l 2iP were subcultured onto a secondary medium containing 1.0 mg/l BA. The induced-microshoots were transferred to either 1/4, 1/2, or full MS medium strengths. The use of a 1/4- strength MS medium resulted in the formation of the highest number of roots and root length compared to a 1/2- and full-strength MS. To improve rooting performance, indole-3-butyric acid (IBA) in various concentrations (up to 1.0 mg/l) was provided to a 1/4-strength MS medium. The average longest root (3.2 ± 0.4 cm) was achieved on a medium supplemented with 0.2 mg/l IBA. A rooting frequency of 100% and the maximum number of roots (6 ± 1.5) per explant were obtained using 1/4-strength MS medium containing 1.0 mg/l IBA, and in vitro plantlets were successfully acclimatized with a 75% survival rate. This study provides an efficient in vitro propagation system for G. tenax.

The Gum Arabic of Acacia senegal (GA) has been reported to treat several diseases, such as kidney failure and cardiovascular and gastrointestinal disease. However, scarce investigation has been made into the phytoconstituents of GA. Obtained GA was macerated in water, then GA aqueous extract was subjected to phytochemical analysis using standard protocols and bioactivity screening by different procedures. Antimicrobial screening was performed using the cup-plate diffusion method against four bacterial strains and one fungi strain. The larvicidal activity was evaluated against the third instar of Culex quinquefasciatus. The phytochemical analysis showed that GA extract contains high amounts of saponins and alkaloids, moderate amounts of cardiac glycosides, and trace amounts of tannins. GA extract exhibited antimicrobial activity against the test organisms, with different zones of inhibition ranging 0 - 18 mm. The larvicidal activity showed significant perfection with increasing extract dose and exposure period with mortality up to 86.7 %. Results reveal that the crude extract of GA contains important biomolecules which has been proved to have substantial larvicidal and antimicrobial activities.

Despite the role of γ-aminobutyric acid (GABA) in plant tolerance to chilling stress having been widely discussed in the seedling stage, very little information is clear regarding its implication in chilling tolerance during the reproductive stage of the plant. Here, we investigated the influence of GABA (1 and 2mM) as a foliar application on tomato plants (Solanum lycopersicum L. cv. Super Marmande) subjected to chilling stress (5°C for 6h/day) for 5 successive days during the flowering stage. The results indicated that applied GABA differentially influenced leaf pigment composition by decreasing the chlorophyll a/b ratio and increasing the anthocyanin relative to total chlorophyll. However, carotenoids were not affected in both GABA-treated and non-treated stressed plants. Root tissues significantly exhibited an increase in thermo-tolerance in GABA-treated plants. Furthermore, applied GABA substantially alleviated the chilling-induced oxidative damage by protecting cell membrane integrity and reducing malondialdehyde (MDA) and H2O2. This positive effect of GABA was associated with enhancing the activity of phenylalanine ammonia-lyase (PAL), catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX). Conversely, a downregulation of peroxidase (POX) and polyphenol oxidase (PPO) was observed under chilling stress which indicates its relevance in phenol metabolism. Interesting correlations were obtained between GABA-induced upregulation of sugar metabolism coinciding with altering secondary metabolism, activities of antioxidant enzymes, and maintaining the integrity of plastids’ ultrastructure Eventually, applied GABA especially at 2mM improved the fruit yield and could be recommended to mitigate the damage of chilling stress in tomato plants.

Accumulation of arsenic in plant tissues poses a substantial threat to global crop yields. The use of plant growth-promoting bacterial strains to mitigate heavy metal toxicity has been illustrated before. However, its potential to reduce plant arsenic uptake and toxicity has not been investigated to date. Here, we describe the identification and characterization of a Nocardiopsis lucentensis strain isolated from heavy metal contaminated soil. Inoculation with this bioactive actinomycete strain decreased arsenic root and shoot bioaccumulation in both C3 and C4 crop species namely barley and maize. Upon arsenate treatment, N. lucentensis S5 stimulated root citric acid production and the plant’s innate detoxification capacity in a species-specific manner. In addition, this specific strain promoted biomass gain, despite substantial tissue arsenic levels. Detoxification (metallothionein, phytochelatin, glutathione-S-transferase levels) was upregulated in arsenate-exposed shoot and roots, and this response was further enhanced upon S5 supplementation, particularly in barley and maize roots. Compared to barley, maize plants were more tolerant to arsenate-induced oxidative stress (less H2O2 and lipid peroxidation levels). However, barley plants invested more in antioxidative capacity induction (ascorbate-glutathione turnover) to mitigate arsenic oxidative stress, which was strongly enhanced by S5. We quantify and mechanistically discuss the physiological and biochemical basis of N. lucentensis-mediated plant biomass recovery on arsenate polluted soils. Our findings substantiate the potential applicability of a bactoremediation strategy to mitigate arsenic-induced yield loss in crops.

Soil arsenic (As) contamination limits global agricultural productivity. Anthropogenic emissions are causing atmospheric CO2 levels to rise. Elevated CO2 (eCO2) boosts plant growth both under optimal and suboptimal growth conditions. However, the crop-specific interaction between eCO2 and soil arsenic exposure has not been investigated at the whole plant, physiological and biochemical level. Here, we tested the effects of eCO2 (620 ppm) and soil As exposure (mild and severe treatments, 25 and 100 mg As/Kg soil) on growth, photosynthesis and redox homeostasis in barley (C3) and maize (C4). Compared to maize, barley was more susceptible to soil As exposure at ambient CO2 levels. Barley plants accumulated more As, particularly in roots. As accumulation inhibited plant growth and induced oxidative damage in a species-specific manner. As-exposed barley experienced severe oxidative stress as illustrated by high H2O2 and protein oxidation levels. Interestingly, eCO2 differentially mitigated As-induced stress in barley and maize. In barley, eCO2 exposure reduced photorespiration, H2O2 production, and lipid/protein oxidation. In maize eCO2 exposure led to an upregulation of the ascorbate-glutathione (ASC/GSH)-mediated antioxidative defense system. Combined, this work highlights how ambient and future eCO2 levels differentially affect the growth, physiology and biochemistry of barley and maize crops exposed to soil As pollution.

This study aims at exploiting salinity stress as an innovative, simple, and cheap method to enhance the production of antioxidant metabolites and enzymes from bacteria for potential application as functional additives to foods and pharmaceuticals. We investigated the physiological and biochemical responses of four bacterial isolates, which exhibited high tolerance to 20% NaCl (wt/vol), out of 27 bacterial strains isolated from Aushazia Lake, Qassim region, Saudi Arabia. The phylogenetic analysis of the 16S rRNA genes of these four isolates indicated that strains ST1 and ST2 belong to genusBacillus, whereas strains ST3 and ST4 belong to genusPlanococcus. Salinity stress differentially induced oxidative damage, where strains ST3 and ST4 showed increased lipid peroxidation, lipoxygenase, and xanthine oxidase levels. Consequently, high antioxidant contents were produced to control oxidative stress, particularly in ST3 and ST4. These twoPlanococcusstrains showed increased glutathione cycle, phenols, flavonoids, antioxidant capacity, catalase, and/or superoxide dismutase (SOD). Interestingly, the production of glutathione byPlanococcusstrains was some thousand folds greater than by higher plants. On the other hand, the induction of antioxidants in ST1 and ST2 was restricted to phenols, flavonoids, peroxidase, glutaredoxin, and/or SOD. The hierarchical analysis also supported strain-specific responses. This is the first report that exploited salinity stress for promoting the production of antioxidants from bacterial isolates, which can be utilized as postbiotics for promising applications in foods and pharmaceuticals.

It is well known that the quality and quantity of bioactive metabolites in plants and microorganisms are affected by environmental factors. We applied heat stress as a promising approach to stimulate the production of antioxidants in four heat-tolerant bacterial strains (HT1 to HT4) isolated from Aushazia Lake, Qassim Region, Saudi Arabia. The phylogenetic analysis of the 16S rRNA sequences indicated that HT1, HT3 and HT4 belong to genus Bacillus. While HT2 is closely related to Pseudooceanicola marinus with 96.78% similarity. Heat stress differentially induced oxidative damage i.e., high lipid peroxidation, lipoxygenase and xanthine oxidase levels in HT strains. Subsequently, heat stress induced the levels of flavonoids and polyphenols in all strains and glutathione (GSH) in HT2. Heat stress also improved the antioxidant enzyme activities, namely, CAT, SOD and POX in all strains and thioredoxin activity in HT3 and HT4. While GSH cycle (GSH level and GPX, GR, Grx and GST activities) was only detectable and enhanced by heat stress in HT2. The hierarchical cluster analysis of the antioxidants also supported the strain-specific responses. In conclusion, heat stress is a promising approach to enhance antioxidant production in bacteria with potential applications in food quality improvement and health promotion.

A gene encoding a β-xylosidase (designated as Thxyl43A) was cloned from strain Thermobifida halotolerans YIM 90462T. The open reading frame of this gene encodes 550 amino acid residues. The gene was over-expressed in Escherichia coli and the recombinant protein was purified. The monomeric Thxyl43A protein presented a molecular mass of 61.5 kDa. When p-nitrophenyl-β-d-xylopyranoside was used as the substrate, recombinant Thxyl43A exhibited optimal activity at 55 °C and pH 4.0 to 7.0, being thermostable by maintaining 47% of its activity after 30 h incubation at 55 °C. The recombinant enzyme retained more than 80% residual activity after incubation at pH range of 4.0 to 12.0 for 24 h, respectively, which indicated notable thermostability and pH stability of Thxyl43A. Moreover, Thxyl43A displayed high catalytic activity (> 60%) in presence of 5–35% NaCl (w/v) or 1–20% ionic liquid (w/v) or 1–50 mM xylose. These properties suggest that Thxyl43A has potential for promoting hemicellulose degradation and other industrial applications.

A Streptomyces isolate, designated strain SYSU D8023T, was isolated from a desert sand sample collected from Gurbantunggut desert, China. The characterisation of the isolate was achieved using a polyphasic taxonomic approach. The isolate was found to be Gram-positive and aerobic. The strain was found to be able to grow at 14–50 °C, pH 6.0–9.0 and in the presence of up to 7% (w/v) NaCl. Strain SYSU D8023T contains LL-diaminopimelic acid as a cell wall diamino acid. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unidentified glycolipid and an unidentified phospholipid. MK-9(H6) and MK-9(H8) were detected as the respiratory quinones, and anteiso-C15:0, iso-C16:0 and anteiso-C17:0 as the predominant fatty acids. Pairwise comparison of the 16S rRNA gene sequences indicated that strain SYSU D8023T has a sequence identity of 97.9% to Streptomyces barkulensis RC 1831T. The DNA G + C content of strain SYSU D8023T was determined to be 70.1 mol%. Based on the analyses of the phenotypic, genotypic and phylogenetic characteristics, strain SYSU D8023T was concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces desertarenae sp. nov. is proposed. The type strain of the species is SYSU D8023T (= CGMCC 4.7455T = KCTC 49023T).

Strain SYSU D8008T was isolated from a desert sand sample collected from Saudi Arabia. The strain was observed to be Gram-stain positive, non-motile and aerobic. It can grow at 15–37 °C, pH 6.0–10.0 and can tolerant up to 7% (w/v) NaCl. Pairwise comparison of the 16S rRNA gene sequence indicated that strain SYSU D8008T shares high sequence similarities with Georgenia deserti SYSU D8004T (96.8%) and Georgenia halophila YIM 93316T (96.8%). Menaquinone MK-8(H4) was detected as the respiratory isoprenologue. The polar lipid profile of strain SYSU D8008T was found to consist of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, two phosphatidylinositol mannosides, an unidentified glycolipid and an unidentified phospholipid. Strain SYSU D8008T was found to contain anteiso-C15:0 and iso-C15:0 as the predominant fatty acids. Galactose, glucose and rhamnose were detected as the whole cell sugars. Based on the phenotypic, genotypic and phylogenetic characteristics, strain SYSU D8008T can be differentiated from other closely related members of the genus Georgenia. The strain SYSU D8008T, therefore, is concluded to represent a novel species of the genus Georgenia, for which the name Georgenia alba sp. nov. is proposed. The type strain is SYSU D8008T (= CGMCC 1.15800T = KCTC 39988T).

A novel endophytic actinobacterium, designated strain EGI 6500139T, was isolated from the surface-sterilized roots of Anabasis aphylla L., collected from Xinjiang, northwest PR China, and subjected to polyphasic taxonomic characterization. Strain EGI 6500139T formed sparse aerial mycelium with rod-like spores. Whole-cell hydrolysates of the isolate contained meso-diaminopimelic acid as the cell-wall diamino acid, glucose as major sugar, and mannose, galactose, xylose and ribose as minor sugars. The polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, one unidentified glycolipid, one unidentified phospholipid and four unidentified polar lipids. The major fatty acids identified were anteiso-C17 : 0, anteiso-C15 : 0, iso-C15 : 0 and iso-C16 : 0. The predominant menaquinones detected were MK-11 and MK-11(H2). The G+C content of the genomic DNA of strain EGI 6500139T was 70.4 mol%. Strain EGI 6500139T showed the highest 16S rRNA gene sequence similarity to Glycomyces lacisalsi XHU 5089T (96.3 %). Phylogenetic analysis showed that strain EGI 6500139T fell within the clade of the genus Glycomyces , and formed a clade with G. lacisalsi XHU 5089T and G. albus CCTCC AA 2013004T. Based on phenotypic, chemotaxonomic and phylogenetic data, strain EGI 6500139T represents a novel species of the genus Glycomyces , for which the name Glycomyces anabasis sp. nov. (type strain EGI 6500139T=JCM 30088T=KCTC 29495T) is proposed.

Antiepileptic drugs are the backbone for epilepsy management. Epilepsy may be accompanied by decreased pain threshold. Thus, anticonvulsant agents with antinociceptive properties are of great importance. This study investigated the possible anticonvulsant and antinociceptive effects of calcitonin in combination with either valproic acid or pregabalin and whether these effects might occur through γ-aminobutyric acid (GABA) modulation. Eighty-four male Balb/C mice were divided into 7 groups: control-naïve, pentylenetetrazole (PTZ)-induced seizures, PTZ-calcitonin, PTZ-valproic acid, PTZ-pregabalin, PTZ-calcitonin-valproic acid (PCV) combination, and PTZ-calcitonin-pregabalin (PCP) combination. PTZ was used in a sub-convulsive dosage, every other day for 11 injections. Drugs were given i.p. 30min before PTZ. After each PTZ injection, mice were put under observation and PTZ-provoked seizures were assessed. After the last dose of PTZ, the hot plate test was used to assess antinociceptive properties. Also, brain GABA neurotransmitter was evaluated by immunoassay. Repeated injection of PTZ induced chemical kindling. Calcitonin was found to have significant antinociceptive property as shown by hot plate latency. The beneficial effects of PCV and PCP combination were statistically significant in epilepsy and pain models as compared to valproic acid and pregabalin. The antiepileptic and antinociceptive activity of calcitonin may not relate to the GABAergic system. Calcitonin enhanced the anticonvulsant and antinociceptive effects of either valproic acid or pregabalin. This new treatment "calcitonin add-on" may provide an improved range of options for patients with refractory epilepsy which is still an important risk factor for sudden death.

Soil arsenic (As) contamination limits global agricultural productivity. Anthropogenic emissions are causing atmospheric CO2 levels to rise. Elevated CO2 (eCO2) boosts plant growth both under optimal and suboptimal growth conditions. However, the crop-specific interaction between eCO2 and soil arsenic exposure has not been investigated at the whole plant, physiological and biochemical level. Here, we tested the effects of eCO2 (620 ppm) and soil As exposure (mild and severe treatments, 25 and 100 mg As/Kg soil) on growth, photosynthesis and redox homeostasis in barley (C3) and maize (C4). Compared to maize, barley was more susceptible to soil As exposure at ambient CO2 levels. Barley plants accumulated more As, particularly in roots. As accumulation inhibited plant growth and induced oxidative damage in a species-specific manner. As-exposed barley experienced severe oxidative stress as illustrated by high H2O2 and protein oxidation levels. Interestingly, eCO2 differentially mitigated As-induced stress in barley and maize. In barley, eCO2 exposure reduced photorespiration, H2O2 production, and lipid/protein oxidation. In maize eCO2 exposure led to an upregulation of the ascorbate-glutathione (ASC/GSH)-mediated antioxidative defense system. Combined, this work highlights how ambient and future eCO2 levels differentially affect the growth, physiology and biochemistry of barley and maize crops exposed to soil As pollution.

Alfalfa sprouts are well known for their nutritive values. Although there are several studies reported the positive impact of elevated CO2 (eCO2) on plants, there are no in-depth, comprehensive studies on how eCO2 could improve the sprouting of plant seeds. Herein, the production of health-promoting metabolites was determined in eCO2 (620 ppm)-treated Alfalfa sprout cultivars (Giza 1, Nubaria and Ismailia 1). eCO2 increased the photosynthetic process and pigment contents, which consequently induced carbohydrates, proteins, fats and fiber accumulation. eCO2 also boosted the levels of vitamins, phenolics, flavonoids and mineral individuals and enhanced the antioxidant capacity of alfalfa sprouts. Interestingly, eCO2 reduced the antinutritional factor l -canavanine content in Ismailia 1 cultivar and improved the anti-inflammatory activities through inhibiting cyclooxygenase-2 and lipoxygenase activity. Therefore, eCO2 is a promising approach to improve the health-promoting prospective of alfalfa sprouts to be a valuable source of nutritious and bioactive compounds in our daily diet.

Grewia tenax is an important nutraceutical plant threatened due to excessive fruit collection and physiological dormancy of seeds. In vitro propagation is required for ex situ conservation of this neglected plant. Improving germination rate is vital for providing the uniform explant material required for propagation and in vitro studies. The aim of this study was to optimize cultivation conditions for in vitro seed germination and micropropagation of G. tenax. Full seed germination was achieved in all treatments. Tests in distilled water medium showed the least number of days for germination and highest seedling length. Full Murashige and Skoog medium produced the maximum number of nodes. Darkness promoted germination rate and seedling length, but decreased the number of nodes per seedling. Benzyladenine and kinetin slightly increased the number of nodes compared to the control. Each uninodal explant cultivated on Murashige and Skoog medium free of plant growth regulators developed into a plantlet within one week. Well-rooted plants were successfully established in a greenhouse with 95% survival rate. This plant growth regulator-free system can successfully overcome seed dormancy and provide a rapid-continuous supply of plant material of G. tenax.

The diversity of actinomycetes associated with the marine sponge Coscinoderma mathewsi collected from Hurghada (Egypt) was studied. Twenty-three actinomycetes were separated and identified based on the 16S rDNA gene sequence analysis. Out of them, three isolates were classified as novel species of the genera Micromonospora, Nocardia, and Gordonia. Genome sequencing of actinomycete strains has revealed many silent biosynthetic gene clusters and has shown their exceptional capacity for the production of secondary metabolites, not observed under classical cultivation conditions. Therefore, the effect of mycolic-acid-containing bacteria or mycolic acid on the biosynthesis of cryptic natural products was investigated. Sponge-derived actinomycete Micromonospora sp. UA17 was co-cultured using liquid fermentation with two mycolic acid-containing actinomycetes (Gordonia sp. UA19 and Nocardia sp. UA 23), or supplemented with pure mycolic acid. LC-HRESIMS data were analyzed to compare natural production across all crude extracts. Micromonospora sp. UA17 was rich with isotetracenone, indolocarbazole, and anthracycline analogs. Some co-culture extracts showed metabolites such as a chlorocardicin, neocopiamycin A, and chicamycin B that were not found in the respective monocultures, suggesting a mycolic acid effect on the induction of cryptic natural product biosynthetic pathways. The antibacterial, antifungal, and antiparasitic activities for the different cultures extracts were also tested.

Background Escherichia coli (E. coli) bacteria normally live in the intestines of people and animals. Most E. coli are harmless and the treatment of the infection could be achieved by using antibiotics, however the effectiveness is still debatable and needs more investigation. Objective Researching the inhibition resonance frequency of square amplitude modulating waves (QAMW) that can inhibit the growth activity of E. coli and its ability to make division. Methods A range of different extremely low frequencies of square amplitude modulated waves (QAMW) from 0.1 to 1.0 Hz from two generators with a constant carrier frequency of 10 MHz, amplitude of 10 Vpp, modulating depth ± 2 Vpp and constant field strength 200 V/m were used to treat E. coli cells at 37 °C. Results The exposure of E. coli to 0.3 Hz QAMW for 90 min was the most inhibited frequency where the bacterial growth inhibited by 42.3%. Furthermore, a significant increase in antibiotic susceptibility to protein and cell wall inhibitors was investigated. Also, results of the chromosomal DNA sequences, dielectric relaxation and TEM indicated highly significant molecular and morphological changes after the exposure. Conclusions We concluded that the exposure of E. coli to QAMW at the inhibiting frequency interfered with the bioelectric signals generated from the bacteria during the cell division and changed the cellular activity and DNA sequences, and these changes lead to a significant inhibition of the bacterial growth. This is a new promising technique that aids to avoid the repetitive use of antibiotics against the bacterial pathogens.

A Gram-positive and non-motile actinobacterium, designated strain EGI 60016T, was isolated from healthy roots of Glycyrrhiza uralensis F. collected from Xinyuan County, Xinjiang Province, China. The 16S rRNA gene sequence of strain EGI 60016T was found to show 97.5 and 97.3 % sequence similarities to Nesterenkonia rhizosphaerae EGI 80099T and Nesternkonia massiliensis NP1T, respectively. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences showed that strain EGI 60016T formed a distinct clade with N. rhizosphaerae EGI 80099T and N. massiliensis NP1T. The polar lipids detected for strain EGI 60016T were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol, an unidentified glycolipid, an unidentified lipid and an unidentified phospholipid. The DNA G+C content was determined to be 64.1 mol%. Other chemotaxonomic features of strain EGI 60016T included MK-7, MK-8 and MK-9 as the respiratory quinones, and anteiso-C15 : 0 and anteiso-C17 : 0 as the major fatty acids. Based on the results of the phylogenetic analysis supported by morphological, physiological, chemotaxonomic and other differentiating phenotypic characteristics, strain EGI 60016T is considered to represent a novel species of the genus Nesterenkonia , for which the name Nesterenkonia endophytica sp. nov. is proposed. The type strain is EGI 60016T (=CCTCC AB 2017176T=NBRC 112398T).

A Gram-positive and aerobic actinobacterium, strain SYSU D8006T, was isolated from a desert sand sample collected from Gurbantunggut desert, China. Phenotypically, the strain was found to grow at 14–50 °C, pH 6.0–9.0 and in the presence of up to 4% (w/v) NaCl. The chemotaxonomic features of strain SYSU D8006T included menaquinone MK-9(H4) as the respiratory quinone, diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside as known polar lipids, iso-C15:0, iso-C16:0, C17:1ω8c and C18:1ω9c as the predominant fatty acids, and arabinose, galactose and glucose as the whole cell sugars. Strain SYSU D8006T shared the highest 16S rRNA gene sequence identity with Blastococcus jejuensis DSM 19597T (98.2%). Based on the analyses of the phenotypic, genotypic and phylogenetic characteristics, strain SYSU D8006T is characterized to represent a novel species of the genus Blastococcus, for which the name Blastococcus deserti sp. nov. is proposed. The type strain is SYSU D8006T (= CGMCC 1.15935T = KCTC 49026T = CPCC 204618T).

Composite surface soil samples were taken from plots (Bahtim permanent experiment) receiving mineral and farmyard (FYM) fertilizer treatments in case of the one-, two- and three-year rotations. These soil samples represent the impact of subjecting such soils for about 100 years to prolonged cropping and fertilization treatments. Soluble, exchangeable, plant-available potassium in conjunction with the potassium intensity of these soils were determined. Moreover, the K-fixation capacity was considered in this study. The obtained data show an obvious decrease in potassium forms in case of the two- and three-year rotation compared with their levels in the one-year rotation. This depends on the crops grown in every rotation. The decrease in K- availability in soils have its impact on crop response to K- applications. This trend should be considered in managing the fertilization programs in the old lands.

Grey Mullet Mugil cephalus L, fingerlings were chronically exposed to sub lethal concentrations of lead (Pb) (0.1 and 0.4 mg/L for twenty-eight. The changes in the leucocytes and serum glucose, protein, and total cholesterol of the fish were determined every seven days in a renewable static bioassay system. At the end of the study, these parameters were significantly (p

This study aims to investigate the bioaccumulation Tissues. The experiment was carried on for 28 days, meanwhile sampling fish weekly. With continued exposure, the accumulations were increased and fish progressively lost their ability to respond to this increase in exposure period. The control group displayed normal behavior during the test period. The lowest concentrations (10 and 15 mg/L Cr6+) had similar behavior to that of the control group. From the dose 20 mg/ L Cr6+, the fish started to show behavioral disorders. 25 mg/L Cr6+ and at the highest concentration (30 mg/L Cr6+) onwards, there was shivering, rather high respiratory disorder and swimming in capsized position in the following order the concentrations of Cr in gills were almost twice, three and four times as high as in the muscle at 20, 25 and 30 ug/L Cr6+ mediums, respectively. The Cr accumulation on the skin of Tilapia for all experimental concentrations was nearly twice as much as in the muscle of samples at the end of experiment.

Light microscopy, scanning and transmission electron microscopy were used to study the morphology and theultrastructure of the pollen grains of Withania somnifera (L.) Dunal. Light microscopic examination revealed that thepollen grain is tri- or tetrazonocoplate, approximately as long as broad measuring 29-μm. Scanning electron microscopic observation showed that surface sculpture is scarbate granulate. Ultrathin sections as examined by transmission electron microscope showed that the pollen contained numerous starch grains, liped drops, endoplasmic reticulum and vesicles of dicotysomes. Two layers of pollen wall were also distinguished; the outer wall (exine divided into ektexine and enexine as well as an inner layer (intine). The nutritive values of Withania pollen were discussed. The importance of studying the ultrastructure of pollen grains as a new tool in plant taxonomy was alsodiscussed.

Fast-growing normal root culture of Vernonia amygdalina, a potent African medicinal plant was established from leaf explants of in vitro raised shoot induced from the stem nodal segments on murashige and skoog (MS) medium containing 0.5 mg l-1 6-benzylaminopurine (BA) in combination with 0.5 mg l-1 naphthalene acetic acid (NAA). In vitro raised plantlets were maintained on MS agar medium and sub cultured at 4 weeks interval and used as leaf explant source. Explants were cultured on halfstrength MS medium supplemented with different concentrations of Indole-3-acetic acid (IAA), indole-3- butyric acid (IBA) and NAA. Basal medium supplemented with IBA at 0.25 and 2.0 mg l-1 and under 16 photoperiod condition favoured induction of the longest root (2.7 ± 1.1 cm) and highest number of roots/explant (38.3 ± 1.1) respectively. After 6 weeks well established roots were separated. Fresh root tissue, in amount of a 100 mg were cultured in 50 ml full-strength MS liquid medium supplemented with 2.0 mg l-1 IBA and under continuous agitation (80 rpm). The biomass of root culture was increased to 2.1949 g after 5 weeks of culture. The root culture was maintained up to 6 weeks. The protocol developed in this study provides a basis for adventitious root induction and for further investigation of medicinally active constituents of this elite medicinal plant.

This report describes in vitro micropropagation of Boscia senegalensis, so-called famine foods, that helped the people in Darfur and Kordofan, Sudan survive during the 1984–1985 famine. Four types of explants prepared from green mature zygotic embryos were cultured on Murashige and Skoog (MS) medium augmented with 1–5 mg/L 6-benzyladenine (BA). The highest number of shoots per explant (14.3±0.9) was achieved on MS medium supplemented with 3 mg/L BA, while the highest shoot length [(3.5±0.4) cm] was obtained with 1 mg/L BA. The shoot cluster, when subcultured to its same medium, significantly increased the rate of shoot multiplication by the end of the third subculture. The maximum mean number of shoots per explant (86.5±3.6) was produced after three multiplication cycles on 3 mg/L BA-supplemented medium. In vitro induced shoots were excised and rooted on half strength MS medium fortified with 0.25 mg/L indole-3-butyric acid (IBA) to obtain complete plantlets. B. senegalensis-regenerated plantlets obtained in vitro for the first time, were hardened and 95% survived under greenhouse conditions.

The effects of different methods of storage on some physical and chemical properties of sun-dried Faba beans were studied. Studied methods of storage were: storage in Makamer (the method most commonly used in Egypt), in tin cans after heating the seeds at 70°C for 2 h, and in tin cans without heating the seeds. The Faba bean seeds (variety Giza 2) were stored for 3, 6 and 9 months in all studied methods. The physical properties studied were seed weight, volume of seeds, bulk density, hydration and swelling coefficients and the percentage of hulls to dehulled seeds. Chemical properties studied were moisture, protein content, total sugar, reducing and non-reducing sugars, starch, phytic acid, ash and minerals such as phosphorus, calcium, iron and magnesium. Storage of Faba bean seeds in Makamer was superior to other methods. Also Faba bean seed can be heated at 70°C and stored in tin cans when required in house.

The effects of the stewing process on some physical properties, organoleptic qualities, chemical composition of unstored and stored faba beans were studied. Hydration and swelling coefficients, as well as organoleptic qualities, were affected significantly by stewing the faba bean seeds. The protein content was decreased noticeably more in stewed faba beans made from seeds stored in tin cans than those stored in Makamer (pits). Total sugars, reducing and non-reducing sugars, starch and pectin contents present in unstored and stored faba beans were decreased after stewing the seeds. Stewing of stored beans either in Makamer or tin cans after heating led to marked reductions in ash, phosphorus, iron, calcium, magnesium and phytic acid contents.