Bioactive Peptides from Legumes and Their Bioavailability

Bioactive peptides (BPs) isolated from legumes have functional properties as healthy foods. These functional effects depend on their stability and bioavailability in the gastrointestinal tract before reaching the target organs. Therefore, it is necessary to disclose the factors that influence it and discuss the technical processing to develop its utilisation. This chapter discusses and summarises the bioactive activities of BPs from various legumes, factors and mechanisms related to the bio-assessability, stability, bio-availability and bioactivity of BPs. Furthermore, the development of BPs bioseparation was also discussed. The results show that the nature of BPs varies greatly depending on the legume source and the production method. Factors that influenced the bio-availability of BPs include molecular weight, charge, amino acid sequence, the presence of specific residues and hydrophobic amino acids, and resistance to the action of peptidase while in the digestive tract. However, some BPs showed increased bio-accessibility and bio-availability after being hydrolyzed by digestive enzymes. Processing technologies such as encapsulation allowing BPs to enter the body and undergo release and degradation by enzymes digestion. Further studies are required to understand the increase in the bioavailability of BPs, the safety of the food components produced, and their use in producing functional foods

A Simple and Sensitive Method for Determination of Sugar Content in Fruits and Culture Media During Fermentation

A colorimetric for sugar determination using cuprammonium reagent containing strong base has been improved with a heating process after a reaction started.  The reaction was started after the sugar or sample containing sugar was added to the cuprammonium reagent consisted of 1 mM CuSO – 0,4 M (NH ) SO – 0,6 M NaOH).  This heat­ ing process could enhance the formation of sugar­cupper ammonium complex, so that the intensity of absorbance increased at wavelength of 280 nm. This simple and sensitive method was applicable for various sugars detection such as sugar fraction after HPLC separation, sugar content in biological extract or in culture medium during fermentation. Interestingly, different from previous report, this method was specific for non polyol sugars

Isolation of Rhizopus oryzae From Rotten Fruit and Its Potency For Lactic Acid Production in Glucose Medium with and without Addition of Calcium Carbonate

Studies on lactic acid production by filamentous fungi Rhizopus oryzae have been explored in the world. Unfortunately, these studies are still limited in Indonesia, particularly studies in lactic acid production by indigenous strain R. oryzae. Four strains obtained from rotten avocado and guava were potential in producing lactic acid (AT1, JT1, AT2, and AT3). Rhizopusoryzae AT3 was used for lactic acid production using 100 g/l glucose medium with and without addition of 7.5 g/l calcium carbonate (CaCO3) at initial fermentation. Addition of CaCO3 increased lactic acid concentration of 59.30%, the concentrations were 11.61 g/l and 18.495 g/l in glucose medium and glucose medium with CaCO3 addition, respectively. Glucose+CaCO3 medium also showed higher productivity, reached continuously from 1 day (0.059 g/l/h) until 5 days fermentation (0.154 g/l/h), whereas highest productivity in glucose medium was reached at 1 day fermentation (0.124 g/l/h) and continued to decrease until 5 days fermentation (0.065 g/l/h)

Isolasi dan seleksi jamur perusak karet dari berbagai sumber kontaminan potensial

Ribbed smoked sheet (RSS) is Natural rubber product, mainly consist of Cis-1,4 polyisoprene and relatively resistant to microbial decomposition with many other natural polymer. Natural rubber contains a minimum of 90% rubber hydrocarbon, plus small amounts of protein, resins, fatty acid, sugars and minerals. It is also possible that microorganisms using impurities as their carbon and energy sources could deteriorate the rubber. Fungi which potentially deteriorate rubber eventually was accidentally taken by raw material areas, raw materials, processing steps, product and old RSS. Therefore it is necessary to isolate fungi and to evaluate potential fungi which deteriorated rubber. The results showed that 158 strains were isolated from various contaminant sources. From these 10 strains were from skin of rubber wood, 7 strains from tappinglump, 16 strains from spoutlump and 10 strains from cuplump, 47 strains from earth around rubber wood, 5 strains from fresh field latex, 3 strains from ammoniated field latex, 12 strains from wet sheet, 7 strains from air in wet RSS processing room, 3 strains from air in smoking room and 7 strains from air in sorting room, 12 strains from RSS product, 11 strains from old RSS product (7 years old namely SU) and 8 strains from wet SU (1 month old namely SDU). Twenty four strains were selected as potential deteriorated rubber fungi. These 24 strains were classified into 10 genera (Aspergillus, Cladosporium, Emericella, Fusarium, Mucor, Neosaâ¢torya, Penicillium, ⢠Pestalotiopsis, Cladobotryum, Pithomyces), and 4 unidentified strains (LM188, T55, SS37,T67). Key Words : Fungi, Ribbed smoked sheet (RSS), isolation, selection, deteriorate rubbe

PROPERTIES OF IMMOBILIZED LIPASE FROM Rhizopus delemar ON POLYPROPYLENE MEMBRANE = SIFAT-SIFAT ENZIM LIPASE AMOBIL DARI Rhizopus delemar DALAM MEMBRAN POLIPROPILEN

ABSTRACT Properties of Rhizopus delemar lipase immobilized on hydrophobic polypropylene membrane were studied by physical adsorption using various concentration of enzyme loading. The result shows that free fatty acid liberation was affected by the enzyme loading, which increased with the increasing enzyme loading. The maximum enzyme adsorption was achieved at 1.2 mg/cm2 membrane. The initial velocity of hydrolysis reaction seems not to be affected by the amount of enzyme bound. The immobilization efficiency was very high reaching more than 60 % at enzyme loading of 0.3 mg/cm2, although a suppression of efficiency was detected at higher loading. The immobilized lipase could hydrolyze 97 % olive oil after 72 h using 1 mg/cm2 of initial enzyme loading. The kinetic parameter indicated that the affinity of the enzyme to substrate was very low (Km = 183 mg/mI). The immobilized enzyme was very stable during storage at 4 °C with proximate half life 65 days. In addition, it maintains ability for subsequent reuses. The membrane can be regenerated by washing for fresh enzyme immobilization. Key words: lipase, Rhizopus delemar, immobilization, polypropylene, membran

Detection of Fish Freshness Using Immobilized ADP-ase and 5\u27-Nucleotidase on Polyacrylamide Gel

ABSTRACT The presence of ADP and IMP in the muscle of fish could be used as an indicator of its freshness. These metabolites could be detected enzymaticaly using ADPase and 51-nucleotidase. The aim of this research was to determine the presence of ADP and IMP in the muscle of fish qualitatively, using immobilized ADPase and 5\u27-nucleotidase on polyacrylamide gel. The results showed that in the non-immobilized form, ADPase has an optimum pH of 6 and stable at pH 5.5-10, while 5\u27-nucleotidase has two optima pH of 6.5 and 9 and it was stable at pH 7-10. Optimum temperature of ADPase and 5\u27-nucleotidase was 45 and 50°C, respectively. In the immobilized form, the activity of ADPase was optimum at pH 6 and it was still stable at pH 5.5 - 7.0 after storage at -20°Cfor 90 days, while 5\u27-nucleotidase was still stable at pH Z5-10 after storage at -20°C for 90 days. Both enzymes were more stable in frozen storage than that of chilled storage. Sensitivity of both enzymes to detect the fish freshness during storage was affected by the presence of free inorganic phosphate derived from other phosphate-containing metabolites. Key words : detection of fish freshness, , immobilized ADPase, immobilized 5\u27nucleotidase

Isolation of Stable Mutants of Candida guilliermondii Producing One Type of ADH

ABSTRAK Mutants of Candida guilliermondii partially deficient in alcohol dehydrogenase (ADH) were isolated using allyl alcohol as a selective agent. On glucose medium containing ally] alcohol produced mutants deficient in ADH1, while mutants free of ADH2 were isolated on ethanol medium containing allyl alcohol. An addition of 1% of yeast extract to the isolation medium resulted in a stability of the mutants against a high concentration of allyl alcohol. On this medium the cells resistant up to 80 mM of allyl alcohol compared to those with a resistance of 10 mM allyl alcohol on basal salt medium without addition of yeast extract. Furthermore, this resistance to ally/ alcohol seems to be related to a stability of the mutants to produce only one type of ADH for a long incubation period (more than 2 years). Cells which were resistant only up to 10 mM of ally] alcohol started to produce two kind of ADHs after six months of incubation. However, this resistance to a high allyl alcohol resulted in a decrease of specific activity of ADHs. Mutant ADH1s had activities only 23 â 50%, where as mutant ADH2s had only 1 â 3% of the parent strain activity. Keywords: Candida guilliermondii , alcohol dehydrogenas

OPTIMASI ISOLALSI LIPASE INDIGENOUS BIJI KAKAO (Theobromcaacao L) = The Optimizing of Isolation of Cocoa Bean Indogenous Lipase (Theobroma cacao L)

Penelitian ini bertujuan untuk mengoptimasi isolasi lipase indigenous biji kakao. Optimasi diawali dengan menentukan keberadaan lipase kemudian optimasi medium ekstraksi dan proses ekstraksi. Hasil penelitian menunjukkan bahwa lipase berada dalam sitosoi. Penghilangan lemak tidak meningkatkan aktivitas lipase. Senyawa polifenol menghambat aktivitas lipase dan penghilangan polifenol dapat meningkatkan aktivitas lipase. Polyvinilpolypirrolidone (PVPP) dapat menghambat polifenol sehingga dapat meningkatkan aktivitas lipase. Konsentrasi PVPP optimum adalah 8 % dari berat biji kakao. Proses homogenisasi optimum diperoleh dalam waktu 10 menit pada kecepatan 10.000 rpm. Medium ekstraksi untuk isolasi lipase biji kakao terbaik adalah bufer fosfat 0,15 M dan pH 7,5 yang mengandung sukrosa 0,6 M dan 1,0mM CaCI2