scholarly journals Antibacterial Bicyclic Fatty Acids from a Korean Colonial Tunicate Didemnum sp.

Marine Drugs ◽  
2021 ◽  
Vol 19 (9) ◽  
pp. 521
Author(s):  
Hiyoung Kim ◽  
Tae Gu Lee ◽  
Inho Yang ◽  
Weihong Wang ◽  
Jungwook Chin ◽  
...  

Five new bicyclic carboxylic acids were obtained by antibacterial activity-guided isolation from a Korean colonial tunicate Didemnum sp. Their structures were elucidated by the interpretation of NMR, MS and CD spectroscopic data. They all belong to the class of aplidic acids. Three of them were amide derivatives (1–3), and the other two were dicarboxylic derivatives (4 and 5). The absolute configurations were determined by a bisignate pattern of CD spectroscopy, which revealed that the absolute configurations of amides were opposite to those of dicarboxylates at every stereogenic centers. Compound 2 exhibited the most potent antibacterial activity (MIC, 2 μg/mL).

1989 ◽  
Vol 107 ◽  
pp. 376-376
Author(s):  
K. D. Abhyankar ◽  
M. L. Vyas

Complete UBV light-curves of RR-Lep and RX-Hya have been obtained during 1983-87 seasons. Preliminary elements were computed using modified Wellmann’s method. With these parameters as inputs Wilson-Devinney program was executed for Blue and Yellow passbands simultaneously in detached and semi-detached modes for both the systems. The semidetached mode fitted better than the other solution for both the systems. For RR-Lep, the absolute dimensions were computed by assuming the primary to be a slightly evolved main sequence star. For RX-Hya, the absolute dimensions were computed using Struve’s spectroscopic data. The following table gives all the elements for both the systems. The secondaries of both the systems are overluminous for their masses suggesting that they have lost considerable mass.


Marine Drugs ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 71 ◽  
Author(s):  
Mudassir Shah ◽  
Chunxiao Sun ◽  
Zichao Sun ◽  
Guojian Zhang ◽  
Qian Che ◽  
...  

Three new polyketides, ketidocillinones A–C (1–3), were discovered from the extract of an Antarctica sponge-derived fungus Penicillium sp. HDN151272. All the structures were deduced by spectroscopic data, including NMR and HRESIMS. The absolute configuration of compound 3 was established by using ECD calculation. Compounds 1−3 can be slowly oxidized to quinone form when exposed to air. Ketidocillinones B and C (2 and 3) exhibited potent antibacterial activity against Pseudomonas aeurigenosa, Mycobacterium phlei, and MRCNS (methicillin-resistant coagulase-negative staphylococci) with MIC values ranging from 1.56 to 25.00 µg/mL.


Marine Drugs ◽  
2019 ◽  
Vol 17 (8) ◽  
pp. 433 ◽  
Author(s):  
Meng Bai ◽  
Guo-Lei Huang ◽  
Rong-Qing Mei ◽  
Bin Wang ◽  
You-Ping Luo ◽  
...  

Three new lactones penicilactones A−C (1−3) were obtained from the mangrove-derived fungus Penicillium sp. TGM112. Their structures and absolute configurations were determined by detailed NMR, MS spectroscopic data, Mo2(OAc)4-induced electronic circular dichroism (ECD), and circular dichroism (CD) spectroscopy. Compound 1 showed antibacterial activity against Staphylococcus aureus with an MIC value of 6.25 μg/mL. Compound 2 showed insecticidal activity against newly hatched larvae of Culex quinquefasciatus with the LC50 value of 78.5 (±0.58) μg/mL.


1991 ◽  
Vol 56 (2) ◽  
pp. 439-448 ◽  
Author(s):  
Stanislav Rádl ◽  
Lenka Kovářová ◽  
Jiří Holoubek

N-Alkylation of IIIa, IIIb, IIId - IIIf and 9-acridanone with 3-bromopropyne in dimethyl sulfoxide in the presence of potassium carbonate yielded N-(2-propynyl) derivatives IVa - IVe and VIa, respectively. Ethyl esters IVa, IVb, and IVe were hydrolyzed to IVf - IVh, respectively. Compounds IVf, IVg, IVctreated with bases yielded N-propadienyl derivatives Va - Vc. On the other hand 2-substituted compounds IVd and IVh did not change under the same conditions. Compound VIa treated with powdered potassium hydroxide in dimethyl sulfoxide at room temperature yielded N-(1-propynyl) derivative VII.


Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5611
Author(s):  
Jie-Yu Zhang ◽  
Juan He ◽  
Zheng-Hui Li ◽  
Tao Feng ◽  
Ji-Kai Liu

In our continuous search for antibacterial agents against Pseudomonas syringae pv. actinidiae (Psa) from kiwi-associated fungi, two pairs of epimeric cytochalasins, zopfiellasins A–D (1–4), were characterized from the fungus Zopfiella sp. The structures were established on the basis of spectroscopic data analysis, while the absolute configurations were determined by single-crystal X-ray diffraction. Compounds 1 and 3 exhibited antibacterial activity against Psa with MIC values of 25 and 50 μg/mL, respectively. This is the first report of anti-Psa activity of cytochalasin derivatives.


Author(s):  
Aylin Oluk

South Anatolian Red (SAR) and Native Southern Yellow (NSY) cattle are commonly reared in the southern region of Turkey. Although physical characteristics of these significant races that are under protection are similar, it is determined in various studies that they have different racial characteristics. The goal of this study is to evaluate lactation characteristics of two different breeds in the same region. It is observed that NSY milk has higher dry matter (%), fat (%), protein (%), lactose (%), total saturated and unsaturated fatty acids (g 100g-1) ratios than SAR milk. In the study, eight volatiles (indoles, ketones, terpenes, aromatic hydrocarbons, esters, carboxylic acids, aldehydes, alcohols) of the cattle types are researched and analyzed and they are compared during lactation periods. At the end of lactation, esters and carboxylic acids increased in NSY milk, while ketones and aldehydes in SAR milk increased. It is seen that alcohols are the most abundant volatile components found in milk of cattle. On the other hand, it is observed that lactation stages, forage type and botanical diversity affect milk flavor and quality.


2017 ◽  
Vol 39 (2) ◽  
pp. 265-276 ◽  
Author(s):  
Kas Saghafi

In several late texts, Derrida meditated on Paul Celan's poem ‘Grosse, Glühende Wölbung’, in which the departure of the world is announced. Delving into the ‘origin’ and ‘history’ of the ‘conception’ of the world, this paper suggests that, for Derrida, the end of the world is determined by and from death—the death of the other. The death of the other marks, each and every time, the absolute end of the world.


Author(s):  
Kyoung- Sun Seo ◽  
Seong Woo Jin ◽  
Seongkyu Choi ◽  
Kyeong Won Yun

The antibacterial activity of three Cupressaceae plants (Thujaoccidentalis,ThujaorientalisandChamaecyparisobtusa) was tested against three bacteria using the agar diffusion method. The ether and ethylacetate fraction of crude methanol extract from the three plants showed potent antibacterial activity against the tested microorganisms. The result showed that Staphylococcus aureus revealed the most sensitivity among the tested bacteria. Thujaoccidentalisether fraction and Thujaorientalis hexane fraction exhibited the highest antibacterial activity against Staphylococcus aureus. E. coli was shown the highest MIC values compared to the other two tested bacteria, which indicates the lowest antibacterial activity against the bacterium. This study promises an interesting future for designing a potentially active antibacterial agent from the three Cupressaceae plants.


2009 ◽  
Vol 54 (2) ◽  
pp. 123-143
Author(s):  
Bernadette Collenberg-Plotnikov

›Ikonen‹ sind heute nicht mehr nur die Ikonen der christlichen Kirche, sondern vor allem die Ikonen der modernen Massenkultur. Beide Arten von Ikonen werden in der neueren Kunstreflexion aufgegriffen: Kunst gilt entweder, verstanden als Erbin der religiösen Ikone, als Phänomen, das Absolutes in singulärer Weise anschaulich er- fahrbar macht. Oder aber die Kunst gilt umgekehrt lediglich als Klasse in der Welt der säkularen Ikonen. Demgegenüber wird im Beitrag erstens die These vertretenwerden, daß die neuere Kunst sowohl Aspekte transzendenter als auch immanenter Ikonen umfaßt. Zugleich ist es aber, so die zweite These, für unser Kunstverständnis charakteristisch, ein theoretisches Kontrastverhältnis zwischen Kunst und Ikone an- zunehmen. Dieses gründet auf einer spezifischen Reflexivität der Kunst, durch die sie sich von der Ikone beiderlei Art kategorial unterscheidet. Today, the word ›icon‹ usually no longer refers to the icons of the Christian church, but to the icons of the modern mass-culture. Both sorts of icons play a key-role in the recent discussion about art: Either art is supposed to be a descendant of the religious icon, a phenomenon that gives us a singular visual experience of the Absolute. On the other hand, art is supposed to be just one class among others in the wide world of the secular icons. In contrast to these two positions this essay contends that modern art comprehends aspects of transcendent as well as of immanent icons. Furthermore, it argues that at the same time it is characteristic for our notion of art to suppose a contrast between art and icon. This contrast is based on a specific reflectivity of art, which marks a categorical difference between art and both sorts of icons.


Antioxidants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 538
Author(s):  
Vita Maria Marino ◽  
Teresa Rapisarda ◽  
Margherita Caccamo ◽  
Bernardo Valenti ◽  
Alessandro Priolo ◽  
...  

Hazelnut peel (HNP), a by-product from the chocolate industry, is considered to be a suitable ingredient to be included in the diet of ruminants. This study aimed to evaluate the effect of feeding dairy ewes with a diet containing HNP on ripened cheese quality, including fatty acid (FA) profile, cholesterol, and tocopherol content, as well as stability during storage under commercial conditions. In total, 10 experimental cheeses were produced with bulk milk obtained from ewes fed a commercial concentrate (C group; n = 5) or a concentrate containing 36% HNP in dry matter (HNP group; n = 5). After 40 days of aging, each cheese was sub-sampled into three slices: one was analyzed immediately (C0 and HNP0), and the other two were refrigerated and analyzed after seven days (C7 and HNP7) and 14 days (C14 and HNP14), respectively. Compared to C, HNP cheese had more than twice as many tocopherols and mono-unsaturated FA and respectively 38% and 24% less of cholesterol and saturated FA. Tocopherols and cholesterol levels remained rather stable up to 14 days of storage regardless of the experimental group, suggesting no cholesterol oxidation. Therefore, the inclusion of HNP in ewe diets could be a valid resource to produce cheese with a healthier lipid profile and higher tocopherols content.


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