To achieve a cost-effective bioconversion of lignocellulosic materials, a novel xylose/glucose co-fermentation process by co-culture of cellulose-utilizing recombinant Saccharomyces cerevisiae (S. cerevisiae) and xylan-utilizing recombinant Pichia pastoris (P. pastoris) was developed, in which ethanol was produced directly from wheat straw without additional hydrolytic enzymes. Recombinant S. cerevisiae coexpressing three types of cellulase and recombinant P. pastoris coexpressing two types of xylanase were constructed, respectively. All cellulases and xylanases were successfully expressed and similar extracellular activity was demonstrated. The maximum ethanol concentration of 32.6 g L with the yield 0.42 g g was achieved from wheat straw corresponding to 100 g L of total sugar after 80 h co-fermentation, which corresponds to 82.6% of the theoretical yield. These results demonstrate that the direct and efficient ethanol production from lignocellulosic materials is accomplished by simultaneous saccharification (cellulose and hemicellulose) and co-fermentation (glucose and xylose) with the co-culture of the two recombinant yeasts.

Four new purified polysaccharides (PAP) were isolated and purified from the Enteromorpha prolifera by alkali extraction, and further characterization was investigated. Their average molecular weights of PAP-1, PAP-2, PAP-3, and PAP-4 were estimated as 3.44 × 104, 6.42 × 104, 1.20 × 105, and 4.82 × 104 Da, respectively. The results from monosaccharide analysis indicated that PAP-1, PAP-2, PAP-3 were acidic polysaccharides and PAP-4 was a neutral polysaccharide. PAP-1 and PAP-2 mainly consist of galacturonic acid, while PAP-3 and PAP-4 mainly contained rhamnose. Congo red test showed that no triple helical structure was detected in the four polysaccharides. The antioxidant activities were investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), Superoxide, and 2, 2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical assay. In vitro antitumor activities were evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. PAP-1 exhibited relatively stronger antioxidant activities among the four polysaccharides in a dose-dependent manner. At a concentration of 1.00 mg/mL, the antioxidant activities of PAP-1 on the DPPH radical scavenging rate, superoxide anion radical scavenging rate, and ABTS radical rate at 1.00 mg/mL were 56.40%, 54.27%, and 42.07%, respectively. They also showed no significant inhibitory activity against MGC-803, HepG2, T24, and Bel-7402 cells. These investigations of polysaccharides provide a scientific basis for the use of E. prolifera as an ingredient in functional foods and medicines.

One new phenolic derivative, 1-(4',5'-dihydroxy-2'-methylphenyl)-pentane-1,4-dione (1), along with eighteen known compounds including eight sesquiterpenoids (2–9), one triterpenoid (10), one bisdpoxylignan (11), one coumarin (12), and seven flavonoids (13–19) were isolated from the dried inflorescence of Tibetan herbal medicine Pulicaria insignis. The structure of 1 was established by spectroscopic methods, including HRESIMS, IR, 1D, and 2D NMR. All isolates were assessed for the cytotoxic activities against MGC-803, T24, HepG2, and HeLa cell lines using the MTT assay. The results showed that compound 1 displayed moderate cytotoxicity against Hela and HepG2, and compounds 3, 4, 5, 6, and 13 exhibited potential cytotoxic activities against the four cell lines with IC50 values ranging from 3.05 to 14.37 μM. Notably, compound 5 exhibited significant anti-proliferative activities against HepG2 cell lines with the IC50 values of 3.05 ± 0.36 μM. Further bioactivity investigation showed that compound 5 could block HepG2 cells in the G1 phase of the cell cycle, thereby inhibiting the growth of HepG2 cells and inducing apoptosis in HepG2 cells.

One new aliphatic ketone alcohol, 15,17-dione-16-hentriacontanol (1), with fifteen known compounds (2-16) were isolated from the ethanolic extract of the whole dried plant of Lepidium latifolium. The antibacterial activities (using minimum inhibitory concentrations (MIC) detection method), the antioxidant activities (using 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and pyrogallol), and the antiproliferative activities (using 3-(4,5dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) method) against three human cancer cell lines were evaluated. The results showed that compounds 2, 9, 10 and 11 with phenolic hydroxyl groups have good antibacterial and DPPH scavenging activities. Compounds 2, 12 and 13, which contain -NH groups have the highest scavenging rates of superoxide anions. The compounds of long-chain alkane containing hydroxyl groups have potent inhibitory activity against MGC-803, HepG2 and T24 cancer cells. The experimental content of this paper enriches the related research of L. latifolium, and greatly expands the market application value of the plant.

A new labdane-type diterpenoid, ent-19-ol-13-epi-manoyl oxide,19-undecane ester, together with ten known diterpenes, were isolated from the ethanolic crude extract of the fresh tubers of Sagittaria trifolia L. The chemical structures...