Dilute acid pretreatment and enzymatic hydrolysis of sorghum biomass for sugar recovery—A statistical approach.

Sorghum is one of the commercially feasible lignocellulosic biomass and has a great potential of being sustainable feedstock for renewable energy. As with any lignocellulosic biomass, sorghum also requires pretreatment which increases its susceptibility to hydrolysis by enzymes for generating sugars which can be further fermented to alcohol. In the present study, sorghum biomass was evaluated for deriving maximum fermentable sugars by optimizing various pretreatment parameters using statistical optimization methods. Pretreatment studies were done with H2SO4, followed by enzymatic saccharification. The efficiency of the process was evaluated on the basis of production of the total reducing sugars released during the process. Compositional analysis was done for native as well as pretreated biomass and compared. The biomass pretreated with the optimized conditions could yield 0.408 g of reducing sugars /g of pretreated biomass upon enzymatic hydrolysis. The cellulose content in the solid portion obtained after pretreatment using optimised conditions was found to be increased by 43.37% with lesser production of inhibitors in acid pretreated liquor.

Effect of chlorocholine chlorid on phenolic acids accumulation and polyphenols formation of buckwheat plants

BACKGROUND: Effect of chlorocholine chloride (CCC) on phenolic acids composition and polyphenols accumulation in various anatomical parts (stems, leaves and inflorescences) of common buckwheat (Fagopyrum esculentum Moench) in the early stages of vegetation period were surveyed. RESULTS: Treatment of buckwheat seeds with 2% of CCC has been increased content of total phenolics in the stems, leaves and inflorescences. On analyzing the different parts of buckwheat plants, 9 different phenolic acids - vanilic acid, ferulic acid, trans-ferulic acid, chlorogenic acid, salycilic acid, cinamic acid, p-coumaric acid, p-anisic acid, methoxycinamic acid and catechins were identified. The levels of identified phenolic acids varied not only significantly among the plant organs but also between early stages of vegetation period. Same changes as in contents of chlorogenic acid, ferulic acid, trans-ferulic acid were found for content of salycilic acid. The content of these phenolic acids has been significant increased under effect of 2% CCC treatment at the phase I (formation of buds) in the stems and at the phase II (beginning of flowering) in the leaves and then inflorescences respectively. The content of catechins as potential buckwheat antioxidants has been increased at the early stages of vegetation period after treatment with 2% CCC. CONCLUSIONS: The obtained results suggest that influence of CCC on the phenolics composition can be a result of various mechanisms of CCC uptake, transforming and/or its translocation in the buckwheat seedlings.

Effects of plant growth promoting rhizobacteria (PGPR) on rooting and root growth of kiwifruit (Actinidia deliciosa) stem cuttings

The effects of plant growth promoting rhizobacteria (PGPR) on the rooting and root growth of semi-hardwood and hardwood kiwifruit stem cuttings were investigated. The PGPR used were Bacillus RC23, Paenibacillus polymyxa RC05, Bacillus subtilis OSU142, Bacillus RC03, Comamonas acidovorans RC41, Bacillus megaterium RC01 and Bacillus simplex RC19. All the bacteria showed indole-3-acetic acid (IAA) producing capacity. Among the PGPR used, the highest rooting ratios were obtained at 47.50 percent for semi-hardwood stem cuttings from Bacillus RC03 and Bacillus simplex RC19 treatments and 42.50 percent for hardwood stem cuttings from Bacillus RC03. As well, Comamonas acidovorans RC41 inoculations indicated higher value than control treatments. The results suggest that these PGPR can be used in organic nursery material production and point to the feasibility of synthetic auxin (IBA) replacement by organic management based on PGPR.

Development of the banana plants 'Prata Anã' and 'FHIA-01' under the effect of paclobutrazol applied on the soil

Under some cultivation conditions, excessive growth of the pseudostem of banana plants can be considered a limiting factor, and thus, the use of growth regulators can constitute a valid alternative. This work aimed to evaluate the action of paclobutrazol on the growth of the pseudostem of banana plants and other characteristics of their development. An experiment was installed with five paclobutrazol doses (0; 0.5; 1.0; 1.5; and 2.0 g of a.i. plant-1) combined with two banana plant cultivars ('Prata Anã' and 'FHIA-01'). Paclobutrazol did not affect the number of days from planting to flowering, total leaf area and leaf emission rate. However, it increased leaf permanence on the plants and sucker number, reduced the foliar area of the leaves emitted after its application and provided an average reduction in pseudostem height of 26 percent.

Em algumas condições de cultivo o crescimento excessivo do pseudocaule de bananeiras pode ser considerado um fator limitante, assim a utilização de reguladores de crescimento pode constituir uma alternativa. O presente trabalho teve por objetivo avaliar a ação do paclobutrazol sobre o crescimento do pseudocaule de bananeiras e outras características do seu desenvolvimento. Para isso foi instalado um experimento com cinco doses do paclobutrazol (0; 0,5; 1,0; 1,5; e 2,0 g de i.a.planta-1) combinadas com dois cultivares de bananeira ('Prata Anã' e 'FHIA-01'). O paclobutrazol não afetou o número dedias do plantio ao florescimento, a área foliar total e a taxade emissão de folhas. Contudo, aumentou a permanência das folhas nas plantas e o número de perfilhos, reduziu a área foliar das folhas emitidas após a sua aplicação e proporcionou uma redução média de 26 por cento na altura do pseudocaule.

Micropropagation of terrestrial orchids, Anoectochilus sikkimensis and Anoectochilus regalis.

Two horticulturally important jewel orchids of the genus Anoectochilus were successfully micropropagated. Isolated nodes of A. sikkimensis collected from Sikkim in Eastern Himalayas and subsequently reared under nursery conditions and A. regalis collected from Western Ghats in Southern India were cultured for 12 weeks on Woody Plant Medium (WPM) to produce a maximum of 4.8 and 5.6 callus--free axillary shoots respectively at 95 and 98% efficiency. During reculture of the explants from in vitro raised shoots under the same conditions, the total number of shoots obtained from the nodes (21.4) and shoot tips (8.2) of A. regalis were significantly higher than those hardy and slow growing shoots of A. sikkimensis (12.3 and 4.3) respectively. Shoots (4-6 cm) were rooted in medium containing NAA (2.70 microM) and activated charcoal (0.2%). The rooted plants established at 95-98% rate in community pots after hardening. After 6 months, green house adapted community potted plants of A. regalis were transferred to natural forest habitat locally with 95 and 70% survival respectively after 12 months. The plants, established in community pots and native forest habitat were free from any morphological and growth defects.

Effect of calcium ion on Hydrilla verticillata thylakoid membrane O2 evolution.

Calcium ion-dependent reactivation of O2 evolution activity has been investigated in Hydrilla verticillata thylakoid preparations. Washing the thylakoids in calcium-free buffer or calcium-free buffer containing 1.5 M NaCl or 1.5 M NaCl plus 20% methanol, reversibly inhibited O2 evolution activity. The activity was restored on addition of calcium as calcium chloride and partially by strontium chloride. Immobilization of thylakoids with glutaraldehyde (GA) arrested the loss in O2 evolution activity caused by calcium-free high salt washing. However, calcium sensitivity was discernible in GA immobilized thylakoids subjected to calcium-free high salt washing. Since glutaraldehyde checks the loss of extrinsic thylakoid polypeptides due to washing, it is assumed that the calcium ion has regulatory functions in the photosynthetic electron transport, besides its interaction with thylakoid proteins.