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1

Surface tension technique as a strategy to evaluate the adsorption of biosurfactants used in soil remediation

Gusiatin Z. M.

Environmental Biotechnology

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2015

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Vol. 11, No. 2

27--33

EN

This study investigated the adsorption of two biosurfactants, non ionic saponin and anionic Reco 10 (a mixture of rhamnolipids). The experiments were performed with three different soils (sandy clay loam, clay loam, clay) and at two soil/biosurfactant ratios, m/V=1/10 and 1/40. Using a tensiometer, surface tension in aqueous biosurfactant solutions and their supernatants was measured and the critical micelle concentration (CMC) was determined. The amount of adsorbed biosurfactants was calculated based on the CMC values. Adsorption of both biosurfactants depended on soil type and m/V ratio. The highest saponin and Reco 10 adsorption was in the soil with the greatest content of clay and organic matter, the highest cation exchange capacity and a m/V of 1/40. Thus, clay soils may need a higher concentration of biosurfactants than sandy or loamy soils for effective pollutant removal.

2

Tannic acid as a cost-effective substitute for saponin in soil remediation

Gusiatin Z. M., Bułkowska K., Pokój T.

Environmental Biotechnology

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2014

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Vol. 10, No. 2

66--72

EN

The efficiency of soil washing with tannic acid (TA) and saponin (SAP) was compared. In the contaminated soil, Cu and Zn were more mobile than Pb. At 3% concentration, both biosurfactants removed similar amounts of Zn (48 and 54%, respectively), SAP removed somewhat more Cu (81%), and TA removed considerably more Pb (63%). SAP removed more Cu due to its higher number of carboxylic groups. TA dissolved the more stable forms of metals because of its higher acidity resulting from the content of phenolic groups. Based on the potential ecological Risk Index (RI), both biosurfactants reduced the risk posed by the contaminated soil from "considerable" (RI=364 ) to "low" (RI=118, on average). These results, and the fact that TA is more than three times less expensive than SAP, make TA an attractive substitute for SAP in soil washing.

3

Biosurfaktanty jako zamienniki syntetycznych surfaktantów

Piotrowski M., Lewandowska J., Wojciechowski K.

Inżynieria i Aparatura Chemiczna

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2011

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Nr 5

90-91

PL

W pracy opisano wyniki badań własności powierzchniowych układu bio-surfaktant saponina-lizozym oraz saponina-ß-laktoglobulina na granicy faz woda-powietrze. Stwierdzono synergctyczny efekt oddziaływań między białkiem i biosurfaktantem prowadzący do większej efektywności obniżania napięcia powierzchniowego i zdolności pianotwórczych mieszanin.

EN

The paper concerns research on intcrfacial properties of saponin-lysozyme biosurfactant and saponin-ß-lactoglobulin mixture at watcr-air interface. A synergistic effect leading to the decrease of surface tension and foaming capability of mixtures, caused by interactions between biosurfactant and protein in the interfacial layer was found.

4

Chemia i aktywność biologiczna czosnku (Allium sativum)

Kwiecień H.

Wiadomości Chemiczne

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2008

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[Z] 62, 9-10

901-942

EN

Garlic (Allium sativum) has historically been one of the most common vegetables to serve as a both spice and medical herb in many countries. One of the outstanding features of the chemical composition of garlic is the large amount of unique organosulfur compounds, which provide its characteristic flavor and odor and most of its potent biological activity. Two classes of primary organosulfur compounds are found in whole garlic cloves: γ-glutamyl-S-alk(en)yl-L-cysteines and S-alk(en)yl-L-cysteine sulfoxides (alliin, metiin, propiin, isallin) (Fig. 1, 2) [5-15]. When garlic is crushed or cut, S-alk(en)yl--L-cysteine sulfoxides are exposed to the enzyme alliinase and thiosulfinates, via intermediate sulfenic acids are formed (Fig. 6) [29-33]. The major thiosulfinate, allicin is a reactive intermediate species that can be transformed, into a variety of compounds including diallyl, methyl allyl and mono- di-, tri-, tetrasulfides, vinyldithiins and ajoenes (Fig. 7-9) [37-49]. Garlic belongs to the Allium species, which accumulate only fructans as their nonstructural carbohydrates [52-59]. Garlic is also known for its production of some unique furostanol saponins, e.g. proto-eruboside-B and sativoside-B1 (Fig. 10-12) [60-63]. The Allium species also contain high levels of flavonides, including apigenin, myricetin and quercetin (Fig. 13) [64, 65], moderate levels of vitamins as well as free amino acids (Arg, Gln, Asn, Glu, and Lys) [66-69]. It was found that the amino acid fraction of Aged Garlic Extract (AGE) contain Maillard reaction products, N-fructosyl glutamine (Fru-Glu), Nα-(1-deoxy-D-fructos-1-yl)-L-arginine (Fru-Arg) (Fig. 14, 15) [74-76], as well as tetrahydro-?-carboline derivatives (Fig. 16, 17) [77-82]. Recently, allixin (Fig. 18), a novel phytoalexin, with the structure 4H-pyran-4-one, as a novel substance with neurotrophic activity has been reported to by synthesized by garlic [83-85]. Garlic has the ability to accumulate the selenium from soil and the major selenium compound in both Se-enriched and unenriched garlic was identified as γ-glutamyl-Se-methyl selenocysteine along with lesser amounts of Se-methyl selenocysteine, selenocysteine, selenomethionine among other compounds (Fig. 19) [86-96]. Pharmacological investigations have shown that garlic has a wide spectrum of actions, not only it is antimicrobial [97], but it also has beneficial effects in regard to cardiovascular and cancer diseases [2, 3, 14, 42]. A number of organosulfur substances derived from garlic such as allicin, allicin-derived organosulfur compounds including sulfides, ajoene, steroidal saponins, flavonides, Fru-Arg, Fru-Glu, organic seleno-compounds and tetrahydro-?-carboline derivatives have been found to have strong antioxidant properties. It has been suggested that garlic can prevent cardiovascular disease, inhibit platelet aggregation, decrease the synthesis of cholesterol and prevent cancer. Thus it may either prevent or delay chronic diseases associated with aging.

5

Saponiny steroidowe

Myszka H., Bednarczyk D.

Wiadomości Chemiczne

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2005

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[Z] 59, 3-4

275--303

EN

Chemistry and biochemistry of glycoconjugates have been a serious challenge for scientists since many years. Among the huge number of glycoconjugates there is a large group of compounds called saponins, specific glycosides that can be found in many plants. However, they can also be collected from some marine organisms. Nowadays, the main source of saponins is the flora of tropical and temperate zones, such a kind of plants: Costus, Discorea, Paris, Solanum, Trigonella, Trillium and Yucca. Furthermore, the large quantities of saponin can be found in food and beverage plants, including oats, peanuts, soybeans, garlic, onion, spinach, leafs of tea, etc. They are active components of some herbs used in therapeutics, e.g. in Poland the fenugreek seeds are used as a decoction for treatment of skin inflammation, moreover they are the components of antisnoring drops, as well as a part of nutrients for culturists. In Orient countries the number of saponins have long been used as pharmaceutical agents, such as those from ginseng, red clover, licorice, horse chestnut, senega and from many others traditional Chinese herbal medicinal plants. The popularity of the discussed group of glycosides comes from their interesting bioactivity. Biological investigations showed that saponins stop the sedimentation process of lipids on the aorta-wall, they slow down the production of sugars, proteins, lipids and bile acids in the liver. Furthermore, they are good antifungal and antibacterial agents, also show an anti-inflammatory and antiallergic activity. It has been found that the crude extract of some plants, especially in the aerial portion, containing the diosgenin glycosides display anti-neoplastic properties against several strains of human cancer cells. Structurally, the saponins are classified as steroid or triterpenoid glycosides depending upon the nature of the aglycone, which is generally called sapogenin. The steroid saponins have cyclopentaphenantrene backbone in aglycone, for example diosgenin, tigogenin, sarsapogenin. Saponins containing nitrogen in aglycone backbone belong also to this group. Triterpenoid saponins have usually 30-carbon atoms in tetra- or pentacyclic aglycone. The carbohydrate residue (hydrophilic part of glycosides), usually a mono-, di-, tri- or tetrasaccharide, is covalently attached to the sapogenin backbone (hydrophobic element). The sugar moiety, in most saponins, is attached to the 3-OH of a sapogenin via the 1,2-trans-glycosidic bond. The difficulties in isolation of homogeneous saponins from natural sources prompted chemists to the synthesis of these type compounds. Chemical synthesis could provide a real way to the availability of required saponins. The largest and also the most interesting class of saponins is the first group - the steroid saponins, because of their biological activity. To this group belong three class of compounds: cholestanoic, furostanoic and spirostanoic saponins.

6

Nowe produkty naturalne o działaniu cytostatycznym

Gryszkiewicz A., Jastrzębska I., Morzycki J.W.

Wiadomości Chemiczne

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2001

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[Z] 55, 9-10

793-820

EN

Secondary metabolites of marine invertebrates continue to attract attention of organic chemists, biochemists, and pharmacologists due to their interesting structures and potent biological activities. One such example is cephalostatin 1 isolated from the Indian Ocean hemichordate Cephalodiscus gilchristi, which exhibited remarkable cytotoxic activity against a broad spectrum of malignant tumor cells. Similar marine alkaloids were found in the lipophilic extract of the tunicate Ritterella tokioka collected off the coast of Japan. These very potent compounds, cephalostatins and ritterazines, belong to the large family of trisdecacyclic pyrazines consisting of two steroid units. The two steroid halves of cephalostatin 1 and other highly cytotoxic members of the family are different. The biological activity of the dimeric steroid-pyrazine marine alkaloids and their limited availability coupled with the new and intriguing structure make them an attractive challenge for the synthetic organic chemists. A few years ago a group of cholestane glycosides was isolated from the bulbs of Ornithogalum saundersiae, a species of the lily family without any medicinal folkloric background. The major component of the mixture of saponins, OSW-1, exhibited sub-nanomolar antineoplastic activity. While OSW-1 is exceptionally cytotoxic against various tumor cells, it showed little toxicity to normal human pulmonary cells. The cytotoxicity profile of OSW-1 against different cancer cell lines was found to be surprisingly similar to that of the cephalostatins, which appears to imply a related mechanism of action [36]. In this review article the synthetic efforts towards these compounds are described. One of the key features of any attempted synthesis of bis-steroidal pyrazines is the central heterocyclic ring. The classical method of pyrazine synthesis involves the dimerization of a-amino ketones. An obvious disadvantage of a-amino ketones dimerizations is their unsuitability for unsymmetrical cross-coupling. Various methods for preparation of unsymmetrical pyrazines were developed. However, the preparation of suitably functionalized steroid units is still an uphill challenge, although a significant progress in this endeavor was achieved. This is exemplified among others by the synthesis of cephalostatin 1. The highly active "interphylal" hybrid analogues, ritterostatins and ornithostatins, were also obtained. Since saponin OSW-1 contains a relatively simple steroid skeleton, it is an attractive synthetic goal. The synthesis of the OSW-1 aglycone, and later the saponin OSW-1, was successfully accomplished. The mode of action of OSW-1 and of the cephalostatin family is not known yet, but it seems that an oxocarbenium ion, which could be generated from both types of compounds, is the likely intermediate responsible for their cytotoxicity.