Environmental friendly alkaline sulfite anthraquinone-methonal (ASAM) pulping with Rumex crispus plant extract of woody materials.

ASAM with Rumex crispus extract organosolv pulping was developed by using 1,5-dihydroxy-3-methoxy-7-methyl-anthraquinone from Rumex crispus root, instead of anthraquinone. ASAM was also produced as a control pulping. Both pulps were made by handsheets from fast growing P.deltoides clone (Samsun p.clone), Robinia pseudoacacia L. and Pinus pinaster grown in Turkey for wood fibrous raw materials. The mechanical consisting tensile, bursting and tear values and optical values of ASAM handsheets yellowness, brightness and whiteness were compared to ASAM with Rumex crispus L. extracted. It is concluded that ASAM with Rumex crispus extract pulping suits well in the manufacturing of special papers.

Photoinhibition of photosynthesis without net loss of photosystem II components in Populus deltoides.

The photoinhibition of photosynthesis was investigated on intact attached leaves and isolated thylakoid membranes of Populus deltoides. Our studies demonstrate that in intact leaves photoinhibition takes place under high irradiance which is more pronounced at higher temperatures. No net loss of Dl and other proteins associated with photosystem II (PSII) were observed even after 64 % photoinhibition suggesting that the degradation of polypeptides associated with PSII is not the only key step responsible for photoinhibition as observed by other workers. Electron transport studies in isolated thylakoid membranes suggested water oxidation complex as one of the damaged site during high light exposure. The possible mechanisms of photoinhibition without net loss of D1 protein are discussed.