Studi Fermentasi Biji Kopi Menggunakan Enzim Proteolitik

Wet fermentation by added proteolytic enzyme can be used for upgrade the taste of coffee. The enzyme was obtained from plant because of ease to get and fulfill the term of Indonesia’s constitution about halal product assurance. This study used two types of proteolytic enzyme; bromelain and zingibain that originated from pineapple and ginger, respectively. Coffee beans were fermented with weight ratio 1:4 and 3:4 (enzyme’s source: coffee beans), and compared with a non-adding control and commercial coffee. Samples were collected after 1, 2 and 3 days. Roasted beans were physical and chemical evaluated according to Indonesia National Standard (SNI-01-3542-2004). Also, the sensorial evaluation of the roasted coffee beans was determined by organoleptic test. Physical and chemical evaluation consist of water content, ash content, coffee extract, ash alkalinity and caffeine content. Sensorial evaluation includes color, aroma and flavor.

Analysis of Chemical Properties and Antioxidant Activity of Sambiloto (Andrographis paniculata Nees.) Leaf Tea Formula as a Functional Drink in Preventing Coronavirus Diseases and Degenerative Diseases

AIM: The purpose of this study was to develop a tea formula of sambiloto leaves, analyzed the chemical properties (polyphenols, tannins, water, extracts in water, total ash, water soluble ash, water-insoluble ash, insoluble acid ash, and water-soluble ash alkalinity) as well as the antioxidant capacity of the formula. METHODS: This research was divided into two stages. The first stage was the formulation of sambiloto leaves tea and the second stage was the analysis of chemical properties (levels of polyphenols, tannins, water, extracts water, total ash, water soluble ash, water-insoluble ash, insoluble acid ash, and water soluble ash alkalinity) and antioxidant capacity analysis. The analysis was carried out on all of the sambiloto leaves tea formulas to determine the effect of the formulations on chemical properties and antioxidant capacity. This study used Microsoft Excel 2013 in data processing management. RESULTS: The highest extract water was at F4, and the lowest was at F1. Based on the analysis, the formula of sambiloto leaves tea was in the range of 1.026–1.734%. Of all the formulas that have been prepared, sambiloto leaves tea formula F1 was obtained the best chemical and antioxidant properties among all formulas, which were composed of 100% sambiloto leaves, 5% honey, and 45% dates. CONCLUSION: Sambiloto leaves have good antioxidant activity and can be used as a drink in the form of an infusion, such as tea. The result of brewing the sambiloto tea formula has faded green color. The polyphenol content of the sambiloto leaves tea formula still did not meet the Indonesia National Standard (≥5.2%), was 1.5–3.1%.

Biomass harvesting leads to soil acidification: a study of mixed crop–livestock farming systems in Madagascar

Soil acidification and declining fertility are widespread in sub‐Saharan Africa. Nutrient depletion is mainly related to nutrient mining driven by biomass removal without replenishment of nutrients through use of fertilisers. Concomitant acidification is due to the high ash alkalinity of harvested biomass. We determined the nutrient content and ash alkalinity of biomass of the main crops produced in smallholder mixed crop–livestock farming systems in the Malagasy Highlands of Madagascar and calculated the soil acidification/alkalinisation occurring through biomass transfer. Samples of rice and forage were collected from 70 rice plots and 91 cultivated forage plots, and 70 manure samples were collected from farms. Nutrient exports induced by crop harvesting resulted in annual losses of 57 kg nitrogen (N), 6 kg (phosphorus) P and 33 kg potassium (K) ha–1 for rice (grain + straw), and 31–51 kg N, 8–9 kg P and 29–57 kg K ha–1 for each forage cut (with three cuts per year on average). The ash alkalinity of samples, calculated as the difference between cation and anion contents, was 49–100 cmolc kg–1 for forage crops, 31 cmolc kg–1 for rice straw, and only 4 cmolc kg–1 for rice grains. Biomass removal caused a loss of nutrients and an increase in soil acidity. Owing to low nutrient retention efficiency during the handling and storage of manure, the traditional input of manure at 5 t fresh matter ha–1 is insufficient to balance nutrient and alkalinity losses in Malagasy mixed crop–livestock farming systems. Maintaining productive and sustainable mixed crop–livestock farming systems requires greater attention to ensuring a nutrient balance at both plot and farm levels.

Scattered paddock trees, litter chemistry, and surface soil properties in pastures of the New England Tablelands, New South Wales

Scattered paddock trees are widespread throughout rural Australia but their effect on soil conditions has received only limited research attention. This study investigated the influence of 3 Eucalyptus species on surface soil properties on different parent materials at both stocked and unstocked sites on the Northern Tablelands of New South Wales. Mineral soil samples to a depth of 5 cm were collected at intervals up to twice the canopy radius away from tree trunks and litter samples were collected at corresponding points. Mineral soils were analysed for pH (CaCl2), organic carbon (C), and extractable phosphorus (P) concentration, while for the litter samples, P, sulfur, cations, and ash alkalinity were determined. Stocking with sheep and cattle increased surface soil acidity and C and P concentrations at each location. However, soils under E. melliodora and E. viminalis showed higher pH and increased C and P concentrations close to the tree stem irrespective of grazing. Soils under E. caliginosa, while having similar patterns of C and P, showed variable acidity patterns with instances of lower pH close to the tree stem. Spatial patterns in soil acidity were associated with the ash alkalinity of litter, indicating litter as a source of alkalinity addition to the soil surface, although different patterns of soil pH could not be fully explained by litter ash alkalinity alone. The close correlation of litter Ca content with ash alkalinity suggests that this element might be a suitable indicator of the acid amelioration capacity of different tree species.

Short-term effects of incubated legume and grass materials on soil acidity and C and N mineralisation in a soil of north-east Australia

Perennial grass growth forms the basis of beef production systems in northern Australia. To improve pasture productivity the woody legume Stylosanthes has been introduced into these native pastures. However, the growth of legumes has been recognised to be a major factor in soil acidification, thereby reducing soil fertility. In order to determine impacts of Stylosanthes scabra (stylo) or Urochloa mosambicensis (urochloa) residues on soil pH, acid neutralising capacity (ANC), and C and N mineralisation, their tops and roots were incubated at a rate equivalent to 10 t dry matter/ha at 25�C for 25 days in topsoil samples of a Mottled-Subnatric Yellow Sodosol from a long-term field experiment under urochloa or under stylo cover. The amount of CO2-C released during the first 2 days of incubation was correlated with the decrease in dissolved organic C. Plant material addition immediately raised the pH and ANC relative to the control. This was related to the amount of ash alkalinity of the plant residues added to the soil. Since the ash alkalinity is a measure for the organic anion content of plant material, it was concluded that the pH buffering was due to protonation of organic anions. During incubation, net N mineralisation was only observed in the urochloa soil amended with stylo leaves. In all other treatments, N added in the residues was immobilised by microorganisms due to the high availability of easily degradable C-sources. Consequently, there was no further change in pH or ANC during incubation, since no significant amounts of H+ were produced or consumed during N conversion processes.

Effect of short-term legume residue decomposition on soil acidity

The accumulation of organic matter has been suggested to be one of the causes of soil acidification. We examined the effect of applying clover shoots, clover roots, and lupin leaves which differed in concentrations of N and excess cations/ash alkalinity on the pH of 2 acidic soils from Western Australia over a 28-day incubation period. Addition of the legume residues at rates of 1·54 and 3·08 g/kg soil increased soil pH by up to 0·6 units at Day 0 and 0·7 units at Day 28 after incubation. The increase in soil pH was the greatest with addition of lupin leaves, followed by clover shoots, and the least with clover roots. The increase in pH correlated well with the amounts of ash alkalinity added as plant materials. Ammonium concentrations were generally increased by addition of the plant materials, but with time the concentrations decreased in the Kojonup soil and increased in the Moora soil. Nitrate concentrations were similar between the treatments, and increased with time. Addition of legume residues slightly increased the pH buffer capacity of both soils at Day 0 but not at Day 28. After 28 days, 37–51% of clover shoots and 36–51% of lupin leaf had decomposed compared with 22-38% of clover roots. The results suggest that rapid changes in soil pH following application of plant materials are related to the concentration of excess cations and decomposition of the material and that the application of legume shoot residues, which usually have high concentrations of excess cations, is not the likely cause of soil acidification.

Pasture legume species differ in their capacity to acidify soil

The capacity of subterranean clover (Trifolium subterraneum L. cv. Clare), medic (Medicago murex Willd. cv. Zodiac), serradella (Ornithopus sativus Brot. line SP1/13), biserrula (Biserrula pelecinus L. line Mor99), and woolly clover (Trifolium tomentosum L.) to acidify soil under N2 fixation was compared in a pot experiment using a poorly buffered sandy soil. The amount of acid produced per kg shoot dry matter (specific acid production) varied betweefin species and with growth stages, ranging from 44 to 128 cmol/kg shoot. Subterranean clover and serradella acidied soil to a greater extent than woolly clover and medic, whereas biserrula acidified soil least. Irrespective of pasture species and growth stage, specific acid production correlated well with concentrations of excess cations and calcium in shoots. Furthermore, total excess cation, ash alkalinity, and calcium in shoots were all good indicators of total acid production across all of the species.

Acidification potential of ten grain legume species grown in nutrient solution

The paper reports the relative acidification potential of 10 N2-fixing grain legume species grown in nutrient solution for 35 days after nodule appearance. The legumes studied were pilosus (Lupinus pilosus Murr. P23342), yellow lupin (Lupinus luteus L. R1171), white lupin (Lupinus albus L. Kiev mutant), narrow-leafed lupin (Lupinus angustifolius L. Gungurru), faba bean (Vicia faba L. Fiord), field pea (Pisum sativum L. Dundale), grasspea (Lathyrus sativus L. S453), chickpea (Cicer arietinum L. T1587), common vetch (Vicia sativa L. Blanchefleur), and lentil (Lens culinaris Med. ILL6002). The species varied considerably in their acidifying ability; proton production ranged from 77 to 136 cmol/kg dry matter. Chickpea and narrow-leafed lupin had the largest acidification potential and field pea the least. The specific acidification (amount of protons produced per kg dry matter) was best correlated with concentrations of excess cations, ash alkalinity, and calcium in plant across the species but was not correlated with plant nitrogen concentration. Total ash alkalinity or total excess cations in shoots provided a good indicator for estimation of total proton production in these species, which were reliant on N2fixation for their source of N. The results have implications for the selection of legumes to be used in sustainable farming systems.

A comparison of proton excretion of twelve pasture legumes grown in nutrient solution

Summary.The use of legumes to improve the productivity of pastures has usually been associated with an increase in soil acidification. The present study compared the acidification potential of 12 N2-fixing pasture legume species/genotypes using a solution culture assay. The legumes were chosen because of their use or potential use in farming systems in the mediterranean zones of southern Australia. The species grown were Trifolium subterraneum L. (vars. Dalkeith, Yarloop and Clare), Trifolium glomeratum L., Trifolium tomentosum L., Medicago murex Willd., Medicago polymorpha L., Medicago truncatulaGaertn., Ornithopus compressus L., Ornithopus sativusBrot., Trifolium vesiculosum and Trifolium balansae. Proton excretion was measured over a period of 21 days from days 40 to 61 after germination. The amount of protons excreted into solution varied between 143 and 265 cmol H+ /kg dry matter for the different species and genotypes. In general, T. tomentosum and T. glomeratum excreted greater amounts of protons per unit biomass than Medicago species and T. subterraneum, which, in turn, excreted more protons than Ornithopus species. The amount of proton excreted per kilogram biomass was well correlated with the concentrations of excess cations over anions and ash alkalinity in plants across all the species. Total acid production was highly correlated with accumulation of excess cations and ash alkalinity, total dry matter production and total nitrogen fixation during the study period. It is suggested that the potential proton excretion by new pasture legume species should be considered when they are introduced into farming systems.