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Manilkara kauki L. Dubard is a tropical plant in the genus Manilkara of family Sapotaceae. This study investigated the total phenolic and flavonoid contents, and antioxidant and antityrosinase activities in different parts of M. kauki (fruits, leaves, seeds, stem barks and woods) and in fractions of stem barks. The total phenolic and flavonoid contents of the methanol and aqueous crude extracts of different parts of M. kauki ranged from 10.87 to 176.56 mg GAE (gallic acid equivalents) per gram of crude extract and 14.33 to 821.67 mg QE (quercetin equivalents) per gram of crude extract, resp. Leaves and stem barks exhibited higher total phenolic and flavonoid contents and antioxidant and anti-tyrosinase activities than fruits, seeds and woods. Stem barks were sequentially extracted with n-hexane, ethyl acetate, methanol and water and then the fractionated extracts were subjected to antioxidant and antityrosinase activities testing. The ethyl acetate and methanol extracts of stem barks exhibited higher total phenolic and flavonoid contents and antioxidant and antityrosinase activities than the n-hexane and aqueous extracts. Moreover, ethyl acetate extract of M. kauki stem exhibited the highest antityrosinase activity. It may be a potential source of tyrosinase inhibitors for pharmaceutical and cosmetic applications.

Free radicals can cause oxidative damage in biomolecules and lead to pathological diseases. Antioxidants can protect against the oxidation of living cells. The aim of this study was to evaluate the total phenolic and flavonoid contents and the antioxidant and antityrosinase activities of different parts of Manilkara zapota and measure the quantity of (+)-dihydrokaempferol in different plant parts. The bark, flowers, fruit, leaves, roots, seeds and wood of Manilkara zapota were extracted with methanol and water. All the crude extracts were evaluated for biological activities and measured the quantity of (+)-dihydrokaempferol using high performance liquid chromatography. The methanol crude extract of the flowers showed the highest total phenolic (743±29 milligrams of gallic acid equivalent per gram crude extract) and flavonoid contents (133.8±3.1 milligrams of quercetin per gram of crude extract). Moreover, it exhibited the strongest antioxidant activity with 2,2-diphenyl-1-picrylhydrazyl (half maximal inhibitory concentration of 22.74±0.67 μg/ml), 2,2’-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (half maximal inhibitory concentration of 20.89±0.17 μg/ml) and ferric reducing antioxidant power values (790.22±0.81 milligrams of trolox equivalent per gram of crude extract). The methanol crude extract of the bark displayed the strongest monophenolase inhibitory activity (half maximal inhibitory concentration of 85.2±2.1 μg/ml), while the methanol crude extract of the roots exhibited the highest diphenolase inhibitory activity (half maximal inhibitory concentration of 33.52±0.68 μg/ml). (+)-Dihydrokaempferol was found in the bark, flowers, leaves, roots and wood. The highest content of (+)-dihydrokaempferol was detected in the methanol crude extract of the bark. These results suggested that the flowers of Manilkara zapota may be used as a source of natural antioxidants and the bark and roots may be beneficial sources of tyrosinase inhibitors.

Camellia oleifera Abel. is commonly known as tea seed oil. The seed of this plant is used for extraction of cooking oil. Camellia oil or tea seed oil is a high-quality cooking oil because it contains a high amount of oleic acid, antioxidants, vitamins, and high smoke point. Tea seed oil may prevent free radical–related diseases. After the oil has been extracted from the seed, the defatted tea seed cake can be used for animal feed, fertilizer, insecticide, pesticide, and molluscicide. Defatted tea seed cake composes of saponins, proteins, and polysaccharides, which exhibited various biological activities. Oleanane-type triterpenoid saponins are the major saponins found in defatted tea seed cake and possess various bioactive compounds with pharmacological activities. Extracts of C. oleifera pericarps or fruit hull also show antioxidant, anti-obesity, and anti-α-glucosidase activities and may be a potential functional food for diabetic patients. Furthermore, flower buds of C. oleifera also contain potent antioxidants.

1,4-Naphthoquinone 1-oxime methyl ethers carrying an ester-substituted aryl pendant at 2-position were concisely prepared as seed compounds with structural flexibility for structure–activity relationship studies on antitumor activity. The key synthetic intermediate was a phthalide–tetralone spiro compound, which was provided by palladium-coupling reaction between 2-bromobenzoate and 1-tetralone followed by OsO4–NMO oxidation.

Obesity is usually considered as an overweight or excess body fat, leading to increased health problems. Obesity is a major risk factor for a number of serious diseases. Decreasing dietary fat absorption, through inhibition of pancreatic lipase activity, has been reported to be one of the most effective ways for managing obesity. The present study was aimed at investigating lipase inhibitors from edible plants. A lipase inhibitor was isolated from n-hexane and ethyl acetate extracts of the ripe fruits of Solanum stramonifolium Jacq. by column chromatography and identified by spectral analysis. Its structure was elucidated as (22R)-3β-benzoyloxy-22-hydroxy-4α-methyl-5α-stigmast-7-en-6-one or carpesterol (1). Carpesterol exhibited moderate lipase inhibition activity with IC50 value of 56.0 μg/mL while orlistat, a well- know pancreatic lipase inhibitor, had IC50 value of 3.5 ng/mL. Moreover, the kinetic properties of carpesterol on pancreatic lipase were evaluated. Carpesterol is a competitive inhibitor and exhibited antagonistic interaction when combined with orlistat on lipase inhibition activity.

The nutritional compositions of farmed sandworms, fed with a commercial shrimp diet, and wild sandworms, caught from the shore line in Chonburi province, Thailand, were investigated. Protein was not different between farmed and wild sandworms (512 and 528 g/kg, p>0.05) but fat content was different (340 and 273 g/kg, p 0.05). However, farmed sandworms were found to contain a higher ratio of n3:n6 PUFA than wild sandworms (0.7:0.4, p

We previously found dehydroxymethylepoxyquinomicin (DHMEQ) inhibited NF-κB activation and showed anti-inflammatory activity in vivo. Here we designed and synthesized analogues of DHMEQ and tested their biological activity as NF-κB inhibitors in human T cell leukemia Jurkat cells. The hydroxyl group at the 2-position of the benzamide moiety was found to be essential for the inhibitory activity. But etherification of this group did not diminish the activity completely. Thus, for further mechanistic studies the hydroxyl group at the 2-position may be useful for extension with a linker and biotin moiety.

A series of sugar-modified derivatives of oxanosine and its carbocyclic analogs were synthesized from natural oxanosine and (−)-2-azabicyclo[2.2.1]hept-5-en-3-one, respectively. Among nucleosides tested for anti-HIV activities in vitro, oxanosine 1, its 5′-monophosphate 9, and 2′-deoxyoxanosine 8 reduced the number of HIV particles in CEM cells to almost the same level as ddI.

Introduction The defatted seed meal of Camellia oleifera Abel., which contains saponins, is used extensively in aquaculture to eliminate unwanted fish and harmful insects during the cultivation of prawns, and as a molluscicide to control Pomacea canaliculata Lamarck. For the quality control of such tea seed meal products, a method for the determination of saponin content is required. Objective To develop a simple, sensitive and specific method for the quantitative determination of saponins in tea seed meal using high-performance thin layer chromatography and densitometry. Methodology Powdered tea seed meal samples were extracted with methanol, filtered, evaporated to dryness and the residue taken up in methanol. Samples, together with methanolic solutions of saponin standard, were analysed by HPTLC on silica gel layers eluted with ethyl acetate:methanol:water (6:3:1.5, v/v/v) and detected at 214 nm. The amounts of saponins were determined from the respective calibration curves obtained by plotting the concentrations of saponin standard against peak area. Results Tea saponin peaks were detected at about Rf 0.40. Good linearity was observed in the range of 0.9–22.2 µg/spot with a correlation coefficient of 0.9978. The limits of detection and quantification were 0.87 and 2.90 µg/spot, respectively. The content of tea saponins in 10 tested samples was found to be between 13.1 and 21.1% w/w. Conclusion The assay proved to be a specific, sensitive and inexpensive method for the quality control of saponins in tea seed meal. Copyright © 2009 John Wiley & Sons, Ltd.

Publisher Summary This chapter profiles the potential usage of tea seeds in human heath and nutrition. Tea seed oil has very high-value nutritional and health protection functions because of its many unsaturated fatty acids. This oil is comprised of 75-80% oleic acid and has a low content of saturated fats. Tea seed oil is bright yellowish and remains liquid even at refrigerated temperatures. High oleic-acid oils are healthy because of their suppressant effect against several degenerative pathologies. Health-promoting effects include lowering blood pressure, cholesterol, and triglycerides, thus preventing cardiovascular diseases and cancer. Its potent antioxidant activity confers protection from free-radical-related diseases, including the hepatoprotective effect. Due to its high content of antioxidants, tea seed oil is used as an emollient in skin care products to minimize signs of aging. Additionally, it is rich in vitamins A, B, and E and contains no natural trans fatty acids. Additionally, tea seed oil is a good source of healthy minerals, such as phosphorus, magnesium, calcium, iron, selenium, and zinc. Tea seed oil can add nutritional value to foods cooked with it. The defatted tea seed cake of C. oleifera contains a large quantity of saponins. Saponins are amphipathic glycosides that are secondary metabolites found in many plants and some animals. Tea seed saponins are harmless to humans, as they are not absorbed into the bloodstream through the intestinal wall. The flower buds of C. oleifera also contain potent antioxidants. They exhibit a protective effect on ethanol- and indomethacin-induced gastric mucosal lesions in rats; antioxidant activities as determined by DPPH scavenging effect; and moderate activities on gastric lesions induced by ethanol in rats.

NF-kappaB is a transcription factor that induces inflammatory cytokines and anti-apoptotic proteins. We designed a new NF-kappaB inhibitor that is based on the structe of the antibiotic epoxyquinomicin C. The designed compound, dehydroxymethyl-epoxyquinomicin (DHMEQ), inhibited the TNF-alpha-induced activation of NF-kappaB, and showed an anti-arthritic effect in mice. Recently, we looked into its mechanism of inhibition. DHMEQ inhibited the TNF-alpha-induced cellular DNA binding of nuclear NF-kappaB, but not the phosphorylation or degradation of I-kappaB. Moreover, DHMEQ inhibited the TNF-alpha-induced nuclear accumulation of p65, a component of NF-kappaB. On the other hand, DHMEQ did not inhibit the nuclear transport of Smad2 and the large T antigen. Also, it did not inhibit the TNF-alpha-induced activation of JNK, but synergistically induced apoptosis with TNF-alpha in human T cell leukemia Jurkat cells. Therefore, DHMEQ specifically inhibited the NF-kappaB-activating pathway in the TNF-alpha-treated cells. Taken together, our data show that DHMEQ is a unique inhibitor of NF-kappaB that acts at the level of the nuclear translocation. It may be useful as an anti-inflammatory and anticancer agent.

A series of the oxanosine and carbocyclic oxanosine derivatives were synthesized to evaluate for their anti-HIV activity. Compound 1, 7 and 9 showed weak anti-HIV activities.

A mixture of molluscicidal saponin compounds was isolated from a methanolic extract of seed meal of Camellia oleifera and tested against Pomacea canaliculata. The most potent saponin fraction showed an LC50 value of 0.66 ppm. This was then used as a marker for quantitative analysis of active molluscicidal compounds in commercial oil- seed camellia meals on HPLC fractionation. The active saponin content was found to be 0.25-1.26% w/w. Methanol was the preferred extraction solvent for analysis of saponin compounds from oil-seed camellia meal. The effect of oil-seed camellia meal on P. canaliculata in a field experiment was determined for three doses: 12.50, 15.63, and 18.75 kg/ha in terms of numbers of dead snails. After one day, all treatments containing oil-seed camellia meal killed 100% of the snails in the sample compared with just 3.8% in the control without any chemical additive. No rice plant damage was detected from any treatments with oil-seed camellia meal, and the dry grain yield was comparable to that of niclosamide treatment. Thus oil-seed camellia meals may be a useful molluscicide for organic rice production.