Genetic structure of three Sorbus latifolia (Lam.) Pers. taxa endemic to northern Bavaria

The Franconian Alb (Bavaria, Germany) is rich in endemic Sorbus taxa, considered as apomictic microspecies and derived by hybridization between Sorbus aria aggregate and Sorbus torminalis (Sorbus latifolia aggregate). Molecular studies using the AFLP technique, neighbour joining, Bayesian clustering, principal coordinate analysis (PCo) and voucher studies were used to investigate genetic structure and origin of adult plants and cultivated offspring of three endemic S. latifolia taxa, namely Sorbus cordigastensis, Sorbus franconica and Sorbus adeana and probable parental species from the S. aria agg. and S. torminalis. The S. latifolia taxa, adults and progeny, showed low genetic variability and a more or less clonal structure, confirming an apomictic mode of reproduction. The investigated S. latifolia taxa were remarkably different among each other, confirming their status as microspecies. The AFLP data confirmed the hybrid origin of the S. latifolia taxa, they were 1.3–1.5 times more closely related to S. aria agg. than to S. torminalis. The S. aria agg. showed a complicate genetic structure and fell into four main groups, two intermediate groups besides Sorbus pannonica and Sorbus aria sensu stricto (S. aria s.str.). Some progeny of S. pannonica was more variable than expected and clustered partly with other groups indicating gene flow within S. aria agg. Different subgroups of the S. aria aggregate may be parental for the S. latifolia taxa, contributing to the remarkable genetic distances between them.     

Das gelbmosaik der eberesche (Sorbus aucuparia L.)

An Ebereschen (Sorbus aucuparia L.) wurden Blätter mit leuchtend gelben Flecken und Rändern sowie vollständig vergilbte Blätter beobachtet. Diese Symptome konnten durch Rinderschiidpfropfung auf gesunde Sämlinge von 5. aucuparia übertragen werden, nicht jedoch auf andere Gehölzarten. Die mechanische Übertragung eines Virus von kranken S. aucuparia‐Sämlingen auf krautige Testpflanzen gelang nicht. In kranken Blattgeweben konnten auch keine virus‐ oder phytoplasmaähnlichen Partikeln festgestellt werden.     

Variation in Two Sorbus Species Endemic to the Isle of Arran, Scotland

A study of the morphology of plants from four species of Sorbus,S. arraensis, S. pseudofennica, S. aucuparia and S. rupicola,two of them endemic to North Arran, suggested that the originof the two endemic groups could have been by hybridization. Variation between individuals within the hybrid groups indicatesthat the two groups, probably of hybrid origin (S. arranensisand S. pseudofennica), could each consist of a set of geneticallyisolated clones reproducing by apomixis, with the possibilityin the case of S. pseudofennica of occasional genetic interchangeby sexual reproduction. The overlap of characters between the two hybrid groups suggeststhat the inflow of genetic material by hybridization and geneticmodification in these groups is continuing. Sorbus arranensis Hedl., Sorbus pseudofennica E. F. Warb., Sorbus aucuparia L., Sorbus rupicola (Syme) Hedl., interspecific hybridization, apomixis     

Carotenoids of Rowan Berries

The berries of Sorbus aucuparia have been investigated for theircarotenoid contents. The pigments identified were: phytofluene,-, ß-carotene, cryptoxanthin, monoepoxy--carotene,monoepoxy-ß-carotene, aurochrome, and mutatochrome.Usually when green fruits ripen the control of carotenoid synthesisis removed when the chlorophylls disappear, there is a rapidincrease of carotenoids in an over-all oxidative manner anddifferent carotenoids appear. However, the results obtainedsuggest that a different mechanism takes place in S. aucuparia.This may be the exception that proves the rule.     

Phytochemical,Free Radical Scavenging and Antifungal Profile of Cuscuta campestris Yunck. Seeds

This work was conceptualized with the goal to investigate the phytochemical, free radical scavenging and antifungal profile of Cuscuta campestrisYunck . seeds. Total phenolics, amino acid and carbohydrate contents were evaluated in ethanolic, acetone and chloroform extract. Effective antioxidant activity was evaluated throughout seven antioxidant methods. The antifungal activity was assessed against eight fungal strains and Candida albicans. The results showed total phenol, flavonoid, flavonols and phenolic acids contents in amount of 1.51 – 6.35 mg GAE/mL, 78 – 425 μg RU/mL, 1.04 – 2.98 mg QU/g and 12.01 – 30.58 μg CAE/mL, respectively. The total amino acids and carbohydrates content ranged from 8.29 to 185.45 μg Gly/mL and from 0.05 to 0.12 μg Glu/mL. The ethanolic extract showed the best antioxidant activity in phosphomolybdenum, DPPH free radical scavenging, ferric reducing power and lipid peroxidation assays. The best activity in ferrous ion chelating and H₂O₂ assays had the acetone extract, whereas the best hydroxyl radical scavenging activity was observed with the chloroform extract. The ethanolic extract at a concentration of 6 mg/mL proved to be the most effective antimycotic, since it inhibited the growth of all tested fungi except Penicillium verrucosum. The obtained results indicate that C. campestris seeds could be attributed to a potential source of natural antioxidants in food and pharmaceutical products.     

Competitive success of southern populations of Betula pendula and Sorbus aucuparia under simulated southern climate experiment in the subarctic

Global warming has been commonly accepted to facilitate species’ range shifts across latitudes. Cross‐latitudinal transplantations support this; many tree species can well adapt to new geographical areas. However, these studies fail to capture species’ adaptations to new light environment because the experiments were not designed to explicitly separate species’ responses to light and temperature. Here we tested reaction norms of tree seedlings in reciprocal transplantations 1,000 km apart from each other at two latitudes (60°N and 69°N). In contrast to past studies, we exposed our experimental plants to same temperature in both sites (temperature of 60°N growing site is recorded to adjust temperature of 69°N site in real time via Internet connection) while light environment (photoperiod, light quality) remained ambient. Shoot elongation and autumn coloration were studied in seedlings of two deciduous trees (Betula pendula and Sorbus aucuparia), which were expected to respond differently to day length. Sorbus as a member of Rosaceae family was assumed to be indifferent to photoperiod, while Betula responds strongly to day length. We hypothesized that (1) southern and northern populations of both species perform differently; (2) southern populations perform better in both sites; (3) autumn phenology of southern populations may delay in the northern site; (4) and Sorbus aucuparia is less dependent on light environment. According to the hypotheses, shoot elongation of northern population was inherently low in both species. An evolutionary consequence of this may be a competitive success of southern populations under warming climate. Southern population of B. pendula was delayed in autumn coloration, but not in growth cessation. Sorbus aucuparia was less responsive to light environment. The results suggest that light provides selection pressure in range shifts, but the response is species dependent.     

Antioxidant properties and phenolic profiling by UPLC-QTOF-MS of Ajwah,Safawy and Sukkari cultivars of date palm

Date palm (P. dactylifera) plays a vital role in ethnomedicinal practices in several parts of the world. There are over 2000 cultivars of date palm that differ in chemical composition and extent of bioactivity. The present study was undertaken to comparatively evaluate the antioxidant potential of three cultivars of date palm (Ajwah, Safawy and Sukkari) from Saudi Arabia and analyze their phenolic constituents in order to draw a rationale for their activity. Antioxidant activities of the date cultivars were evaluated by different quantitative methods including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging assay, total antioxidant capacity, reducing power, total phenolic (TPC), flavonoid (TFC) and tannin content (TTC), while qualitative phenolic composition was determined using ultra performance liquid chromatography coupled to quadropole time of flight mass spectrometry (UPLC-QTOF-MS). All the three date extracts showed good DPPH radical scavenging (IC₅₀ 103–177 μg/mL) and hydroxyl radical scavenging (IC₅₀ 1.1–1.55 mg/mL) activity and total antioxidant capacity (IC₅₀ 87–192 μg/mL). The reducing power was also comparable to that of ascorbic acid, used as standard in above experiments. All the three samples contain significant amount of major antioxidant components (phenolic, flavonoid and tannin) that successfully correlates with the results of radical scavenging assays. UPLC-QTOF-MS revealed a total of 22 compounds in these date cultivars classified into common phenolics, flavonoids, sterols and phytoestrogens. Significant variation in the degree of antioxidant activity of these three date cultivars can be attributed to the difference in the content and composition of phenolic compounds.     

Glassworts as Possible Anticancer Agents Against Human Colorectal Adenocarcinoma Cells with Their Nutritive,Antioxidant and Phytochemical Profiles

In this study, the possible uses of glassworts as potential food ingredients and their antiproliferative activity against colorectal adenocarcinoma cells together with their antioxidant and phytochemical profiles were investigated for the first time. MeOH extracts of five different taxa collected from different localities were screened for their antioxidant capacities by DPPH (IC₅₀ 2.91 – 5.49 mg/ml) and ABTS (24.4 – 38.5 μmol TE/g extract) assays. Salicornia freitagii exhibited the highest DPPH radical scavenging activity. LC/MS/MS analysis displayed that vanillic acid and p‐coumaric acid were two main phenolic compounds in the extract. Salicornia freitagii extracts also exhibited high antiproliferative activity against HT‐29 (IC₅₀ 1.67 mg/ml) and Caco‐2 (IC₅₀ 3.03 mg/ml) cells for 72 h. Mineral analysis indicated that all the species with different proportions of elemental components contained high amount of cations. These results indicate that investigated glassworts, with their high phenolic and mineral contents and also notable antioxidant and cytotoxic properties, may be utilized as a promising source of therapeutics.     

Investigations on Antioxidant,Antiproliferative and COX‐2 Inhibitory Potential of Alkaloids from Anthocephalus cadamba (Roxb.) Miq. Leaves

In the present study, an ayurvedic medicinal plant, Anthocephalus cadamba (Roxb .) Miq . commonly known as ‘Kadamb’ was explored for its potential against oxidative stress and cancer. The fractions namely AC‐4 and ACALK (alkaloid rich fraction) were isolated from A. cadamba leaves by employing two different isolation methods and evaluated for their in vitro antioxidant and antiproliferative activity. The structure of the isolated AC‐4 was characterized tentatively as dihydrocadambine by using various spectroscopic techniques such as ESI‐QTOF‐MS, ¹H‐ and ¹³C‐NMR, DEPT, COSY, HMQC, and HMBC. Results of various antioxidant assays viz. 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), ABTS cation radical, superoxide anion radical scavenging, and plasmid nicking assay demonstrated that both the fractions viz. AC‐4 and ACALK possess ability to scavenge DPPH, ABTS radicals and effectively protected plasmid pBR322 DNA from damage caused by hydroxyl radicals. Further, when both fractions were evaluated for their potential to suppress growth of HeLa and COLO 205 cells, only ACALK fraction showed antiproliferative effects. ACALK exhibited GI₅₀ of 205.98 and 99.54 μg/ml in HeLa and COLO 205 cell lines, respectively. Results of Hoechst staining in cervical carcinoma (HeLa) cells confirmed that ACALK induced cell death in HeLa cells via apoptotic mode. Both the fractions also inhibited COX‐2 enzyme activity.     

Variation in Phenolic Content,Profile, and Antioxidant Activity of Seeds among Different Paeonia ostii Cultivated Populations in China

The purpose of this study was to analyze the phenolic profiles of seeds from fifteen Paeonia ostii cultivated populations in China and identify their relationship with antioxidant activities and associated environmental factors. Thirteen individual phenolic compounds were quantitatively determined by HPLC, and (+)‐catechin was the most abundant phenolic compound in the seeds. Correlation analysis showed that phenolics were the most effective antioxidant compound class by evaluating DPPH, ABTS, and hydroxyl radical scavenging activities as well as ferric reducing antioxidant power. Latitude and annual rainfall had significant effects on the contents of many phenolic compounds, and elevation was only significantly correlated with gallic acid content. Within fifteen P. ostii cultivated populations, the seeds of Tongling population exhibited the highest phenolic contents and strongest antioxidant activities. These results suggest that Tongling population has a relatively high utilization value and a potential for sources of natural antioxidants.     

Variation in Phenolic Profile, β‐Carotene and Flavonoid Contents,Biological Activities of Two Tagetes Species from Pakistani Flora

The objective of present study was to evaluate the variation in phenolic profile, β‐carotene, flavonoid contents, antioxidant and antimicrobial properties of Tagetes erecta and Tagetes patula (T. erecta and T. patula) through different in vitro assays. Antioxidant activity was determined through 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical scavenging and inhibition of linoleic acid peroxidation assays and antibacterial and antifungal activities studied using the disc diffusion and resazurin microtiter‐plate assays against bacterial and fungal strains. Moreover, total phenolics (TP), total carotenoids (TC) and total flavonoids (TF) were also determined. Highest (TP 35.8 mg GAE/g) and TF (16.9 mg CE/g) contents were found in MeOH extract of T. patula. T. erecta extract showed higher TC contents (6.45 mg/g) than T. patula extract (6.32 mg/g). T. erecta exhibited the highest DPPH radical‐scavenging activity (IC₅₀) (5.73 μg/mL) and inhibition of linoleic acid peroxidation (80.1%). RP‐HPLC revealed the presence of caffeic acid, sinapic acid and ferulic acid in Tagetes extracts, m‐coumaric acid in T. erecta whereas chlorogenic acid in T. patula extract only. Both extracts possessed promising antimicrobial activity compared to the ciprofloxacin and flumequine (+ve controls) against Bacillus subtilis and Alternaria alternate. Both extract were rich source of polyphenols exhibiting excellent biological activities.     

Variation in Polyphenolic Profiles,Antioxidant and Antimicrobial Activity of Different Achillea Species as Natural Sources of Antiglycative Compounds

A comparative study was carried out on the methanolic extracts from six Achillea species and the examined polyphenols from these plants on the formation of advanced glycation end‐products (AGE) in vitro. A. pachycephala which was richer in flavonoids (15 mg quercetin/g W) and phenolics (111.10 mg tannic acid/g DW) with substantial antioxidant activity (IC₅₀ = 365.5 μg/ml) presented strong anti‐AGE properties. Chlorogenic acid, luteolin, quercetin and caffeic acid were identified as the major polyphenols in the extracts by HPLC. In general, polyphenolic content follows the order of A. pachycephalla > A. nobilis > A. filipendulina > A. santolina > A. aucheri > A. millefolium. Most extracts exhibited marked anti‐AGE ability in the bovine serum albumin (BSA)/methylglyoxal (MG) system, though A. pachycephala showed the highest potential. The formation of AGEs was assessed by monitoring the production of fluorescent products and circular dichroism (CD) spectroscopy. Diminution in free radical production (assessed by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) assays) is discussed as potential mechanism for delay or reduced AGE. The results demonstrate the antiglycative, antioxidant and antimicrobial potential of Achillea species which can be attributed to polyphenols content and the effectiveness on generation of AGEs, thus Achillea species can be considered as natural sources for slowing down glycation related diseases.     

Identification of carotenoids with high antioxidant capacity produced by extremophile microorganisms

In this study, the carotenoids produced by the extremophile microorganisms Halococcus morrhuae, Halobacterium salinarium and Thermus filiformis were separated and identified by high-performance liquid chromatography connected to a diode array detector and a tandem mass spectrometer. The in vitro scavenging capacity of the carotenoid extracts against radical and non-radical species was evaluated. In halophilic microorganisms, the following carotenoids were identified: bacterioruberin, bisanhydrobacterioruberin, trisanhydrobacterioruberin and their derivatives. In the thermophilic bacterium, the carotenoids all-trans-zeaxanthin, zeaxanthin monoglucoside, thermozeaxanthins and thermobiszeaxanthins were identified. The antioxidant capacities of the carotenoid extracts of H. morrhuae (trolox equivalent antioxidant capacity = 5.07 and IC₅₀ = 0.85 μg mL⁻¹) and H. salinarium (trolox equivalent antioxidant capacity = 5.28 and IC₅₀ = 0.84 μg mL⁻¹) were similar and higher than those of the bacterium T. filiformis (trolox equivalent antioxidant capacity = 2.87 and IC₅₀ = 2.41 μg mL⁻¹). This difference is related to the presence of acyclic carotenoids with both large numbers of conjugated double bounds and of hydroxyl groups in the major carotenoid of the halophilic microorganisms.     

Reproductive strategy and ploidy determine the genetic variability of Sorbus aria

Sorbus aria (L.) Crantz (common whitebeam) from the Canary Islands has not been characterised genetically. We analysed the genetic variability of 184 individuals belonging to seven natural populations of S. aria from the Canarian Archipelago and the Iberian Peninsula. Our main aims were to obtain essential information to enable the exploration of the genetic relationship between populations from the Canary Islands and the Iberian Peninsula; to establish the existence of a spatial genetic structure and formulate appropriate management and conservation genetics strategies. Genetic variation was analysed using nine polymorphic microsatellite loci. The Canary Island populations (triploids) were found to have very low genetic variability and to be considerably differentiated from the populations from the peninsula (diploid and triploid), although with a connection to the Sierra Nevada population in the south of the Peninsula. This population, in turn, had many different genotypes, which is indicative of the existence of various origins. The level of genetic diversity was higher in all-diploid populations, which, in addition, presented a greater interpopulation gene flow, possibly the result of a prevalence of sexual reproduction. On the other hand, the triploid populations presented lower levels of genetic variability, with a significant degree of fixed heterozygosity, possibly due to asexual reproduction, mainly by apomixis. The reproductive biology and ploidy appear to be responsible for the levels of genetic variability in S. aria.     

Potential cow milk xanthine oxidase inhibitory and antioxidant activity of selected phenolic acid derivatives

Xanthine oxidase (XO) found in all mammals and excess activity leads to urolithiasis. The cow milk XO was purified to 305‐fold with a specific activity of 8.76 EU/mg and overall yield of 87% by using DEAE‐Sepharose chromatography. The phenolics showed potent XO inhibitory effect with K_i, P1 (0.412), P2 (0.632), P3 (0.585), P4 (0.886), P5 (1.633), P6 (0.503), P7 (2.882), P8 (3.761), P9 (4.487), and P10 (5.841) μM. The phenolics P9 and P10 exhibited uncompetitive inhibition; the phenolics P1, P2, P3, P4, and P6 showed competitive inhibition, and other phenolic acids showed noncompetitive inhibition. The studied phenolic compounds showed potent antioxidant activity and expressed as EC₅₀, ranged from, DPPH (4.2–25.8 μg mL^–1), ABTS (10.2–42.5 mmol TE 100 g^–1), and FRAP (6.3–36.8 mol Fe (II) 100 g^–1). The results obtained from this study might be utilized for design of XO inhibitors and as antigout agent.     

Towards a better understanding of polyploid Sorbus (Rosaceae) from Bosnia and Herzegovina (Balkan Peninsula), including description of a novel,tetraploid apomictic species

Sorbus subgenus Soraria encompasses taxa originating from spontaneous hybridization between members of subgenera Aria and Sorbus disjunctly distributed across Europe and Asia. Using molecular data (amplified fragment length polymorphisms, plastid DNA sequences and nuclear microsatellites), flow cytometry (allowing for the determination of ploidy and mode of reproduction) and morphology, we disentangled the relationships among polyploid cytotypes and explored their relationships with their diploid ancestors. Among others, we focused on a large, geographically isolated hybrid population in Bosnia and Herzegovina. Molecular and morphological analyses confirmed the distinct position of this population in relation to its parental (S. aria and S. aucuparia) and other hybridogenous taxa originating independently from the same parents in different parts of Europe. After establishing its genetic and morphological divergence, we describe the isolated Bosnian population as a new tetraploid apomictic species, S orbus bosniaca , discuss its taxonomic status and propose conservation measures to protect the locus classicus of this new Balkan endemic. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 670–685.     

Glutathione S-transferase pi (GST-pi) inhibition and anti-inflammation activity of the ethyl acetate extract of Streptomyces sp. strain MJM 8637

To investigate the anti-cancer properties of soil-borne actinobacteria, MJM 8637, the glutathione S-transferase pi (GST-pi) assay, anti-tumor necrosis factor (TNF)-α assay, the level of antioxidant potential by DPPH radical scavenging activity, NO scavenging activity, and ABTS radical scavenging activity in ethyl acetate extract were determined. The 16S rDNA sequencing analysis revealed that Streptomyces sp. strain MJM 8637, which was isolated from Hambak Mountain, Korea, has 99.5% similarity to Streptomyces atratus strain NBRC 3897. The physiological and the morphological characteristics of the strain MJM 8637 were also identified. The ethyl acetate extract of MJM 8637 inhibited TNF-α production approximately 61.8% at concentration 100 μg/ml. The IC₅₀ value of the strain MJM 8637 extract on GST-pi was identified to be 120.2 ± 1.6 μg/ml. In DPPH, NO, and ABTS radical scavenging assays, the IC₅₀ values of the strain MJM 8637 extract were found to be 977.2 μg/ml, 1143.7 μg/ml, and 454.4 μg/ml, respectively. The ethyl acetate extract of the strain MJM 8637 showed 97.2 ± 1.3% of cell viability at 100 μg/ml in RAW 264.7 cell viability assay. The results obtained from this study suggest that the ethyl acetate extract of Streptomyces sp. strain MJM 8637 could be considered as a potential source of drug for the cancers that have multidrug resistance with its GST-pi inhibition and anti-inflammation activities, and low cytotoxicity.     

Essential Oil and Bioactive Compounds Variation in Myrtle (Myrtus communis L.) as Affected by Seasonal Variation and Salt Stress

The effect of different NaCl concentrations (control, 2, 4 and 6 dS/m) and three harvesting times in different seasons including spring (9 April), summer (5 July), and fall (23 September) was evaluated on essential oil (EO) yield, composition, phenolic, flavonoid content, and antioxidant activity of myrtle. Essential oil yield ranged from 0.2% in control and fall to 1.6% in moderate salinity (4 dS/m) and spring season. The main constituents obtained from gas chromatography/mass spectrometry analysis were α‐pinene, 1,8‐cineole, limonene, linalool, α‐terpineol, and linalyl acetate in which α‐pinene ranged from 11.70% in moderate and fall to 30.99% in low salinity (2 dS/m) and spring, while 1,8‐cineole varied from 7.42% in high salinity (6 dS/m) and summer to 15.45% in low salinity and spring, respectively. Salt stress also resulted in an increase in total phenolic, flavonoid content, and antioxidant activity. The highest antioxidant activity based on DPPH radical scavenging activity, reducing power (FTC) and β‐carotene/linoleic acid model systems was found in plants harvested in spring and summer in high stress condition. The lowest IC₅₀ values obtained in 6 dS/m in spring (375.23 μg/ml) followed by summer (249.41 μg/ml) and fall (618.38 μg/ml). Eight major phenolic and flavonoid compounds were determined in three harvesting times using high performance liquid chromatography analysis. In overall, late harvesting time of myrtle in fall can lead to reduce the most of major EO components, while it can improve the amount of phenolic acids.     

Contaminants in tilapia (<Emphasis Type="Italic">Oreochromis mossambicus</Emphasis>) from the Salton Sea,California, in relation to human health,piscivorous birds and fish meal production

A summary of all existing information collected since 1980 on contaminants in tilapia from the Salton Sea is presented and risks to humans and fish-eating birds assessed. Of the 17 trace elements, 42 organic pesticides and 48 polychlorinated biphenyls (PCBs) analyzed in tilapia whole body and fillet samples, only selenium (Se), arsenic (As) and possibly dichlorodiphenyltrichloroethane (DDE) were found at levels high enough to be of concern for fish, birds or humans. Average current concentration of arsenic (As) was 0.7 μg g⁻¹ wet weight (ww) in whole body samples and 1.2 μg g⁻¹ ww in fillet samples, or 2.8 and 5.7 μg g⁻¹ dry weight (dw), respectively. Inorganic As averaged 0.006 μg g⁻¹ ww (0.03 μg g⁻¹ dw) in fillet samples, which represented 0.3% of total As. By U.S. Environmental Protection Agency (U.S.EPA) guidelines, As levels in tilapia pose no threat of non-cancerous adverse health effects in children and adults. As is a known human carcinogen, however, and U.S.EPA cancer risk assessment procedures indicate that a weekly consumption of 540 g (19 oz) or more for 70 years would increase the upper bound cancer risk by 1 in 100,000 consumers exposed. Average current Se concentration was 2.2 μg g⁻¹ ww in tilapia whole body samples and 1.9 μg g⁻¹ ww in fillet (8.3 and 9 μg g⁻¹ dw, respectively). Consumption of Se-contaminated tilapia was found to present no unacceptable risk for adverse health effects for adults consuming up to 1000 g (35 oz) of fillet per week even when additional intakes of Se from other food items were taken into account. Similarly, children weighing 30 kg or more could safely eat up to 430 g (15 oz) of tilapia fillet on a weekly basis. A health advisory issued by the State of California in 1986 recommended, on the basis of Se levels, that consumption of any fish from the Salton Sea be limited to 114 g (4 oz) every 2 weeks, but the rationale and calculations on which that advisory was based are unavailable. We suggest that the existing health advisory for Salton Sea tilapia be revised by the state in light of this new information and updated risk parameters for As and Se. Dichlorodiphenyltrichloroethane (DDE) was detected in all samples of tilapia, with current levels averaging 0.085 μg g⁻¹ in whole tilapia and 0.032 μg g⁻¹ in fillet ww. Compared to screening values proposed by the U.S. EPA, these concentrations are unlikely to cause non-cancerous health effects in anglers, but one might exceed a 1 × 10⁻⁵ increase in cancer risk by consuming more than 4 meals of tilapia per week. Similarly, polychlorinated biphenyls (PCBs) were detected in tilapia fillets at levels that may increase the cancer risk for those anglers also eating more than 4 meals of tilapia per week. These determinations are based, however, on DDE concentrations reported from a small sample size (n = 4), and on screening values recommended by U.S.EPA. The paucity of DDE and total DDT analyses carried out in recent times on the edible portion of Salton Sea tilapia warrants additional analyses in order to evaluate the need for issuance of a fish consumption advisory with regards to long term exposure to total DDT via consumption of Salton Sea fish. With regards to the potential impact on fish and piscivorous birds, we cannot conclude whether concentrations of As in tilapia could pose a threat to the fish and the birds feeding on them. Se concentrations, however, may be elevated enough to negatively affect fish health, and reproduction and immune systems of piscivorous birds, but definitive studies are lacking. Total DDT and PCB concentrations in whole tilapia are not elevated enough to have adverse effects on fish and piscivorous birds. Fish harvesting for fish meal production has been proposed for the Salton Sea. Based on whole fish dry weight values of 61% protein and 21% ash, and the determined contaminant levels, tilapia could yield a meal of reasonable quality for use in formulating poultry, livestock and aquaculture feeds. Guest Editor: John M. Melack Saline Waters and their Biota